How much does a heart weigh on average? How much does a human heart weigh?
in women 1:180. And many more interesting facts about the human body can be found
How much does an adult human heart weigh? What is the size of a human heart?
What is the weight of a human heart?
How much does a human heart weigh?
The heart of any person is approximately equal to the size of his fist. The weight of an adult human heart is 220-260 g, and the heart weight ratio is
(to total body weight) is equal to 1:170 for men,
for women – 1:180. And many more interesting facts about the human body can be found
Weight of a baby's heart at birth. After 8 months it becomes twice as large. An adult man's heart weighs 300 grams, a woman's heart weighs several grams. Well, I think everyone knows that the size of a person’s heart is equal to the size of his fist.
The average weight of an adult’s heart is g. Heart length cm, width cm, height (thickness) cm. The thickness of the ventricles: left - 0.8 - 1 cm, right - about 0.5 cm.
Human → What is the largest human organ and what is the average weight of the human brain?
The names of the fingers of the French are: pus, index, major, anulaire, oriculaire.
Each human finger bends approximately 25 million times during a lifetime.
The size of a person's heart is approximately equal to the size of his fist.
The weight of an adult's heart is g.
The human body contains only 4 minerals: apatite, aragonite, calcite and cristobalite.
The human brain generates more electrical impulses per day than all the world's phones combined.
The average human brain weighs 1.4 kilograms, while the size is in this case it really doesn’t matter: Einstein’s brain weighed 0.2 kg less than normal, so if your friend’s hat is too small for you, don’t flatter yourself - it’s not a fact that you’re smarter than him.
Despite its small volume and the fact that the brain is 90% water, it consumes 25% of all the oxygen and sugar the body needs.
The phenomenon in which a person loses the ability to see due to strong light is called “snow blindness.”
The total weight of bacteria living in the human body is 2 kilograms.
In the human brain, chemical reactions occur in one second.
Children are born without kneecaps. They appear only at the age of 2-6 years.
From the moment of birth, there are already 14 billion cells in the human brain, and this number does not increase until death. On the contrary, after 25 years it decreases by 100 thousand per day. In the minute you spend reading a page, about 70 cells die. After 40 years, brain degradation accelerates sharply, and after 50, neurons (nerve cells) dry out and brain volume decreases.
In psychiatry, a syndrome accompanied by depersonalization, impaired perception of time and space, own body And environment, officially (!) called “Alice in Wonderland.”
How to fix it? Either reduce oxygen consumption (lose weight, which is not acceptable), or increase the volume of the heart and blood distilled at a time. This, in fact, is the meaning of training the heart - to increase its internal volume.
The larger the heart volume, the more nutrients gets a heart at a time
The larger the heart volume, the less often it can contract
The less often the heart contracts (works), the less it wears out.
L and D – cardiac hypertrophy.
Please note that I said increasing the volume of the heart, not increasing the size of the heart. These are very important things. Because the first is very useful, and the second, on the contrary, is very harmful! The fact is that cardiac hypertrophy can be good and bad. When the increase in volume occurs due to stretching of the walls of the heart muscle (L-hypertrophy) - this is very good! This allows us to pump more blood at a time - which is what we need. But when the heart grows due to thickening of the walls of the heart muscle (D - hypertrophy) - this is very bad. This is the so-called myocardial hypertrophy due to a diastole defect. In general, such an unpleasant thing as a heart attack is the consequences of precisely such changes in the heart.
Fine. How to achieve good hypertrophy and avoid bad? Everything is very simple. There is no need to work at a pulse close to maximum (beats)! You need to work long and often at an average pulse () beats per minute. For most people, a minute of pulses is ideal. At the usual healthy person at rest, the pulse is 70 beats per minute. When such a person begins to do some kind of cyclic long work(trains with iron, runs or walks quickly) his pulse begins to increase in order to supply all organs of the body with an increased amount of oxygen due to the load. His pulse reached 130 beats per minute. A person in this situation can stabilize the load and continue working without increasing intensity. If he continues this training for an hour, the “flexibility” of his heart will begin to improve. The muscles will drive a huge amount of blood through the heart and it will gradually begin to stretch. If you train this way often (from 3 times a week for 60 minutes), then over time the heart will stretch and its volume will increase significantly. Accordingly, the volume of blood pumped per pulse beat will increase, endurance will increase, and the number of pulse beats at rest will decrease.
Heart medications work well with supplements such as St. John's wort, garlic, and ginkgo biloba.
Every day, the heart produces enough energy to drive a car 32 km. In a lifetime, this is equivalent to going to the moon and back.
Cocaine affects the electrical activity of the heart and causes spasm of the arteries, which can lead to a heart attack even in healthy people on the planet.
It has always been believed that men are more susceptible to heart problems. But this is not true at all. To prove this fact, here's a statistic: Every year in the United States, 10 times more women die from heart disease than men.
A kitchen faucet must be left fully open for 45 years to dispense an amount of water equal to the volume of blood pumped by the heart in an average human life.
CT scans of mummies revealed that heart disease was surprisingly common in Egypt. There were probably other factors that led to heart disease back then that didn't include smoking, fast food, or watching too much TV.
People who live alone are twice as likely to die from sudden cardiac arrest and heart attack as those who live with relatives or even have a roommate.
The first heart transplant was performed in 1967 by Dr. Christian Barnard from South Africa. A human heart was transplanted into the body of Louis Washansky. Although the patient only lived 18 days after surgery, this case is considered the first successful heart transplant.
Galen of Pergamon, a prominent surgeon to the Roman gladiators, proved that the arteries are filled with blood and not air, as Hippocrates had previously assumed. However, he also believed that the heart acts as a low-temperature oven that holds the heat of the blood and pumps it from one part to another through tiny holes.
In most people, red blood cells consist of normal hemoglobin A, but in part of the population they consist of hemoglobin S. Such red blood cells have a sickle shape instead of a round one, which is why they carry oxygen less well, have reduced durability and many other disadvantages. At the same time, there are quite a lot of carriers of sickle cell anemia, especially in regions of tropical and subtropical climates where malaria is common.
It turns out that hemoglobin S significantly reduces the likelihood of contracting malaria, which, within large populations, prevents the degeneration of the mutant gene associated with it.
The amount of blood in the body, although it is a variable value for different people (approximately 7 percent of body weight), does not exceed 7-10 liters.
Frozen red blood cells can last up to 10 years.
The first blood banks appeared during the Second World War. Their founder is considered to be the American Charles Drew, who, in cruel irony, died in 1950 from loss of blood as a result of a car accident.
The five largest organs in the human body are the heart, liver, brain, lungs, and kidneys.
The existence of the heart was well known to the ancient Greeks, who called it Kardia, which is reflected in the words "cardiologist" and "tachycardia". Aristotle believed that the heart is the seat of the soul and the center of man.
The largest artery in our body is the aorta, its diameter is close to the diameter of a garden water hose.
The human heart creates pressure that can spray blood over a distance of 10 meters.
The blood in a smoker’s body is cleared of nicotine in men in 6 months, in women in 3. In women it is faster due to natural monthly blood loss.
American scientists have recently found that people with a wide social circle are less likely to suffer from heart disease. Sociable people they smoke less, have lower blood sugar levels and lower blood pressure, all of which have a positive effect on the functioning of the heart.
The red blood cells of an intensively working hand contain much more hemoglobin and oxygen than the red blood cells of a non-working hand.
A one-time blood test taken from the cerebral and femoral arteries shows that the portion of blood sent from the aorta to the brain is warmer and contains more young, small red blood cells with more active substances than the blood going into the femoral artery.
The blood plasma entering the fertile uterus contains more proteins and other nutrients than that sent to other organs.
There is a phenomenon of “regional blood flow”, when, regardless of the value of the general blood pressure, the volume of blood entering the vessels of a particular organ can unexpectedly increase or decrease tens of times, while the blood flow in neighboring vessels remains unchanged. So, through one renal artery it increases 14 times, and at the same second in the adjacent celiac artery of the same diameter, the blood flow does not change.
When measuring pressure in certain places of the brain, lungs, adrenal glands, and heart, “mosaic circulation” can be observed, when in one of the areas of these organs there is no blood movement, but in others it is more intense than normal.
The amount of blood in the body, although it is a variable value for different people (approximately 7 percent of body weight), does not exceed 7-10 liters. This is clearly not enough to fill all the blood vessels. The fact is that there is a redistribution of blood between organs and tissues. Those who are working most intensively at the moment receive more blood, others - less. So, after a very heavy lunch, the digestive system works vigorously, a significant part of the blood is sent to its organs, and for normal brain function it begins to be insufficient, and the person experiences drowsiness.
The human heart creates pressure that can spray blood over a distance of 10 meters.
Let's take a closer look at the principles and patterns of heart function.
Cardiac cycle
When an adult is calm, his heart contracts at approximately the rate of cycles per minute. One pulse beat equals one cardiac cycle. At this speed of contraction, one cycle is completed in approximately 0.8 seconds. Of which, the contraction time of the atria is 0.1 seconds, the ventricles are 0.3 seconds, and the relaxation period is 0.4 seconds.
The frequency of the cycle is set by the cardiac pacemaker (the area of the heart muscle in which impulses arise that regulate the heart rate).
The following concepts are distinguished:
- Systole (contraction) - this concept almost always means contraction of the ventricles of the heart, which leads to a push of blood through the arterial bed and maximization of pressure in the arteries.
- Diastole (pause) is a period when the heart muscle is in the stage of relaxation. At this moment, the chambers of the heart fill with blood and the pressure in the arteries decreases.
So, when measuring blood pressure, two indicators are always recorded. Let's take the numbers 110/70 as an example, what do they mean?
- 110 is the top number (systolic pressure), that is, the pressure of the blood in the arteries at the moment of heart contraction.
- 70 is the lower number (diastolic pressure), that is, this is the blood pressure in the arteries at the moment the heart relaxes.
A simple description of the cardiac cycle:
Cardiac cycle (animation)
At the moment of relaxation of the heart, the atria, and even the ventricles (through open valves), fill with blood.
Performing a pumping function in the circulatory system, the heart constantly pumps blood into the arteries. The human heart is a kind of pump that ensures constant and continuous movement of blood through the vessels in the right direction. Simple calculations show that over 70 years the heart ordinary person performs more than 2.5 billion strokes and pumps 250 million liters of blood [approx. 1] .
Bicuspid and tricuspid valves ensure blood flows in one direction - from the atria to the ventricles.
A healthy heart contracts and unclenches rhythmically and without interruption. There are three phases in one cardiac cycle:
- The atria, filled with blood, contract. In this case, blood is pumped through the open valves into the ventricles of the heart (at this time they remain in a state of relaxation). Contraction of the atria begins at the point where the veins flow into it, so their mouths are compressed and blood cannot flow back into the veins.
- Contraction of the ventricles occurs with simultaneous relaxation of the atria. The tricuspid and bicuspid valves that separate the atria from the ventricles rise, slam shut, and prevent blood from returning to the atria, while the aortic and pulmonary valves open. Contraction of the ventricles forces blood into the aorta and pulmonary artery.
- Pause (diastole) is a short period of rest for this organ. During a pause, blood from the veins enters the atria and partially flows into the ventricles. When a new cycle begins, the blood remaining in the atria will be pushed into the ventricles - the cycle will repeat.
One cycle of the heart lasts about 0.85 seconds, of which the time of contraction of the atria is only 0.11 seconds, the time of contraction of the ventricles is 0.32 seconds, and the longest is the rest period, lasting 0.4 seconds. The heart of an adult at rest works in the system at about 70 cycles per minute.
A certain part of the heart muscle specializes in issuing control signals to the rest of the heart in the form of corresponding impulses of an autowave nature; this specialized part of the heart is called the cardiac conduction system (CCS). It is this that ensures the automaticity of the heart.
69. A human head remains conscious for 15-20 seconds after it is cut off.
Muscles and bones are the frame of our body, thanks to them we move and even just lie.
70. You tense 17 muscles to smile and 43 to frown. If you don't want to strain your face, smile. Anyone who often walks around with a sour expression for a long time knows how hard it is.
71. Children are born with 300 bones, but adults have only 206.
72. In the morning we are a centimeter higher than in the evening.
73. The strongest muscle of the human body is the tongue.
75. To take a step, you use 200 muscles.
76. The tooth is the only organ incapable of regeneration.
77. Muscles shrink twice as fast as they build.
78. Some bones are stronger than steel.
70. House dust consists of 70% shed skin.
71. The tooth is the only part of a person that lacks the ability to repair itself.
72. The brain is 80% water.
73. More living organisms live on the body of one person than there are people on Earth.
74. One hair can support a weight of 3 kg.
75. Medium human head weighs 3.6 kg.
76. Over the course of his entire life, a person produces so much saliva that it would be enough for 2 large swimming pools.
How to treat atrial fibrillation
The last few decades are characterized by doctors as a special period cardiovascular diseases. Many of them manifest themselves openly and bring with them serious painful sensations, literally knock you off your feet. But there are also diseases that develop quietly, without attracting increased attention. This is where the danger lies. One of these hidden ailments is atrial fibrillation - a disturbed rhythm of the heart muscle.
How many beats per minute
The heart of an untrained man
The muscle of this organ of an untrained person is weak, so it is unable to push out a large volume of blood. This fact has long been known to everyone. In this case, blood circulation can be increased only by increasing heart rate. With this way of working the heart, the pause time is reduced. But the muscle of the “internal engine” should receive rest during this period of time. This means that the heart of an untrained person gets tired quickly, but gets little rest. With significant physical exertion, the increase in its performance occurs no more than 3 times and only due to heart rate.
I have a heart rhythm disorder
Heart rhythm disturbance is a common pathology of cardiac activity, consisting of a deviation from the normal rhythm and systematicity of the contractile function of the heart muscle.
The heart is a vital organ of the human body, so even the slightest violation the rhythm of cardiac activity has a detrimental effect on the functioning of all structures.
How much does the average human heart weigh?
The heart is a muscular organ in humans and animals that pumps blood through blood vessels.
Functions of the heart - why do we need a heart?
Our blood provides the entire body with oxygen and nutrients. In addition, it also has a cleansing function, helping in the removal of metabolic waste.
The function of the heart is to pump blood through blood vessels.
How much blood does the human heart pump?
The human heart pumps several liters of blood in one day. This amounts to approximately 3 million liters per year. That works out to 200 million liters over a lifetime!
The amount of blood pumped within a minute depends on the current physical and emotional load - the greater the load, the more blood the body requires. So the heart can conduct from 5 to 30 liters through itself in one minute.
The circulatory system consists of about 65 thousand vessels, their total length is about 100 thousand kilometers! Yes, we didn't make a mistake.
Circulatory system
Circulatory system (animation)
The shape is determined by age, gender, physique, health, and other factors. In simplified models, it is described by a sphere, ellipsoids, and the intersection figures of an elliptical paraboloid and a triaxial ellipsoid. The measure of elongation (factor) of a shape is the ratio of the largest longitudinal and transverse linear dimensions hearts. With a hypersthenic body type, the ratio is close to one, and with an asthenic body type, it is about 1.5. The length of the heart of an adult varies from 10 to 15 cm (usually 12-13 cm), width at the base 8-11 cm (usually 9-10 cm) and anteroposterior size 6-8.5 cm (usually 6.5-7 cm) . The average heart weight in men is 332 g (from 274 to 385 g), in women - 253 g (from 203 to 302 g).
Towards midline the body of the heart is located asymmetrically - about 2/3 to the left of it and about 1/3 to the right. Depending on the direction of the projection of the longitudinal axis (from the middle of its base to the apex) on the anterior chest wall, transverse, oblique and vertical positions of the heart are distinguished. The vertical position is more common in people with a narrow and long chest, the transverse position is more common in people with a wide and short chest. The heart can independently provide venous return only in vessels currently located above the top of the atria, i.e. by gravity, by gravitational forces (Ivan Golovanov “New theory of blood circulation and health”, Moscow, 2001, p. 48). Performing pumping functions in the circulatory system, the heart constantly pumps blood into the arteries. Simple calculations show that over the course of 70 years, the heart of an average person performs more than 2.5 billion beats and pumps 250 million liters of blood.
On these pages you can find out:
How much does a person's soul weigh?
How much does a tiger weigh
How much does the Tsar Bell weigh?
How much does the Olympic torch weigh?
How much does a leopard weigh?
23. During life, the human small intestine is about 2.5 meters long. After his death, when the muscles of the intestinal wall relax, its length reaches 6 meters.
24. A person has approximately 2 million sweat glands. The average adult loses 540 calories with every liter of sweat. Men sweat about 40% more than women.
25. Right human lung holds more air than the left one.
26. An adult takes approximately one breath (and one breath) per day.
27. Over the course of a lifetime, the female body reproduces 7 million eggs.
28. The human eye is capable of distinguishing 0 shades of color.
29. There are parabacteria in the human mouth.
30. Papaphobia is the fear of the Pope!
With each contraction, about 70 g of blood is ejected from the heart; per day it pumps at least 9450 liters of blood. On average, an adult's heart beats 70-75 times per minute. Heart rate depends on several factors, including the size of the body. In general, the larger the organism, the lower the heart rate. Thus, a woman’s heart makes 6-8 more contractions per minute than a man’s heart. In a newborn, the heart rate can reach 130 beats per minute.
The hair can be stretched to 1/5 of its length, and after that it returns to its original state.
The strength of the hair is comparable to aluminum and can withstand a load of 100 to 200 g.
Hair is hygroscopic, that is, it is able to absorb moisture - this is due to the structure of the hair.
Hair is resistant to weak acids, but does not tolerate alkaline compounds well.
Hair can accumulate certain substances, which allows it to be used as an identifier.
The lifespan of hair is different: on average, men have 2 years on their heads, and women have 4-5 years.
Redheads have the most Thick hair, but there are fewer of them than others.
Black hair is the largest of all, and can be 3 times thicker than blonde hair.
The baby's first hairs appear in the womb, at about 4-5 months of pregnancy.
Hair grows at an average rate of 0.4 mm per day.
As you age, your hair becomes shorter and thinner.
Hair is mainly composed of proteins.
The hair follicle has three phases of life: anagen (hair growth phase), catagen (transition phase), telogen (resting phase).
Women are less likely to go bald than men because women's hair roots sit 2 millimeters deeper in the skin than men's.
How much blood does the heart pump?
5 liters of blood circulate throughout the entire cardiovascular system of an adult. With each contraction, the heart pushes blood into the arteries. Approximately 12 strokes are enough to fill, for example, a standard liter bag. These numbers are correct at rest. During physical activity, the volume of blood pumped increases several times. With maximum physical exertion - 4-5 times and with each blow more than 200 ml of blood is released into the arteries.
Can a person live without a heart?
In the absence of heart contractions, after 3-5 minutes, loss of consciousness immediately occurs and the gradual extinction of all vital functions. The heart has no duplicates! Nature “took care” of creating numerous paired organs for humans and only left the heart alone. This means that nature has created a perfect and reliable design, ensuring the performance of the function in natural conditions for the body.
Section. Two people: an experienced one and a beginner. The coach gives them intense work (crossfit, running, sparring, iron, etc. no matter what). But in an experienced person, the heart is trained and has a stretched volume of 1,000 - 1,200 ml. And the newcomer has a heart with a volume of 600 ml. Problem: what will happen? Answer: An experienced person’s heart rate will rise to 130 and he will complete the workout without any problems with benefits for the heart. But for a beginner, the heart rate will jump to... He will be red and out of breath. “Come on!” shouts the coach. "More!". And the beginner’s heart gradually dies at this time, causing micro-infarctions due to the diastole effect. A beginner does not train his heart, but ruins it, earning myocardial dystrophy. And I see this regularly in many sections.
80% of the human body's heat leaves the head.
The average human head weighs 3.6 kg.
How much does a human heart weigh?
Usually the size of a human heart is compared to the size of his fist, which is approximately true - the heart is the same size as a clenched human palm. Bigger size the heart of an athlete, constant physical activity leads to the growth of all muscle groups, which include the heart muscle. The weight of an adult human heart is equal to the weight of two to three medium apples.
The average weight of a man's heart is 332 grams, a woman's gram.
The heart is a powerful and uninterrupted engine in the human body, the main function of which is to pump blood from the venous vessels to the arterial ones. This is probably the only organ whose work a person feels and hears. When we are worried, the heart beats frightfully fast, when we are happy, it is exciting, and when a bright feeling settles in it - love, it just begins to sing!
Despite its small size (the length of the muscular organ is from 10 to 15 cm, the width is 8-11 cm), the heart copes with a colossal load. It pumps about 7,000 liters of blood per day. If you place this amount of liquid medium in standard 200-liter barrels, you get 35 containers, and in one minute of operation a powerful heart pump can completely fill a bath with blood. The principle of the heart is the rhythmic contraction of the heart muscle. The heart cavity is divided into two atria and two ventricles. The right part refers to the “arterial” heart, the left is venous. Venous vessels deliver “waste” blood to the heart, and oxygen-enriched blood moves through the arteries. Veins have a thinner wall and the pressure in them is much less than in the arteries. This feature helps to distinguish the type of bleeding if they rupture: dark blood flows out of the vein in a continuous stream, while in arterial bleeding bright red, scarlet blood is ejected with pulsating movements.
When measuring blood pressure, two indicators are recorded: upper and lower. The upper pressure is called systolic, at this moment the heart muscle contracts. The second indicator is diastolic pressure; the heart is in a relaxed state during this period. Normal blood pressure readings are 120/80 mm Hg. , deviation in big side can cause a disease called hypertension, or, to a lesser extent, hypotension.
How the heart works
The formation of cardiac tissue begins in the embryonic stage of fetal development. The child receives nutrition through the mother's placenta, but in order for its own organs to begin to grow and develop, nutrients must be delivered to every cell of the body. Therefore, the heart is the very first functional organ that begins to grow and form in a tiny organism. By the 22nd day of pregnancy, the embryo has its first heartbeat; by the 26th day, its own blood circulation is formed in the growing body. At birth, the baby's heart is no larger than a strawberry.
The baby's heart becomes similar to the heart of an adult by the tenth week of development: at this moment, septa and heart valves appear in it.
After the tiny “motor” begins its responsible work, the heart rate is almost the same as that of an adult: beats per minute. By the seventh week of development, the heart “accelerates” to beats and during a CTG study, future mom hears his rapid knock. At birth, the pulse “calms down” to the normal beats per minute.
The entire work cycle of the heart muscle consists of two phases: systole and diastole. At the moment of relaxation of the heart muscle, the atria and partly the ventricles are filled with blood. Then the atria contract and the liquid medium is pushed into the ventricles, while the veins at the mouth are compressed, which prevents blood from flowing into them. After this, the atria relax, the ventricles contract and blood is pushed into the aorta through the left ventricle and into the pulmonary artery through the right. The mitral and tricuspid valves at this moment block the return of blood to the atrium. After this, the cycle repeats again and so on throughout a person’s life.
The heart rate is “set” by the sympathetic nervous system. The release of adrenaline produced by the adrenal glands into the blood increases the strength and number of heart contractions, and the production of acetycholine has the opposite effect.
Listening to heart sounds is done using a stethoscope, invented by the French doctor Rene Laennec (the aesculapian was guided by the fact that it is quite difficult to hear the heart of ladies with a magnificent bust, simply by pressing the ear to the chest). Another invention is related to the human heart - this is the second hand on a watch, the patent belongs to the English doctor John Flower, he introduced an innovation to make it convenient to count a person’s pulse.
The heart rate in women is higher than in men, with an average of 78 beats per minute. For men it is beats per minute. Although it is believed that the heart beats continuously, this is not entirely true. The period when the heart works is the contraction of the heart muscle; in a relaxed state, the heart begins a period of rest.
This explains the efficiency of the human motor; nature has arranged its activity in such a way that the heart has the opportunity to take a break from its hard and constant work.
It is known that no engine will work without fuel. For the heart, oxygen is such a “fuel”. In order to work for a day, the heart muscle will need 130 liters of pure oxygen, its average consumption per minute is 2.5 liters. One heartbeat is equal to the amount of energy it takes to lift an object weighing 200 grams to a height of one meter. The energy generated by a human engine in a day would be enough for a passenger car to travel 32 kilometers, and in a month the heart can produce such an amount of energy that if used, a person of average weight can easily be lifted to the top of the highest mountain - Chomolungmas. In a lifetime, a person could travel to the moon and back, using the resources of his own heart!
The heart is not just an important organ in the human body, it is a symbol of love. The ancient Egyptians believed that ring finger is connected by a special channel to the heart muscle, hence the custom of putting a wedding ring on it. In Russia, a monument to the heart was erected; it is located in the city of Perm in the courtyard of the Heart Institute. The granite giant weighing about four tons symbolizes the fiery red human heart, like a steppe poppy. The weight of a human heart determines his age, height, and physical fitness. And yet, this is not only a muscle that triggers physiological processes in the human body, it is a small and capacious place where human feelings, experiences and secrets are stored.
Our body is a complex structure consisting of individual components (organs and systems), the full functioning of which requires constant supply of nutrition and disposal of decay products. This work is performed by the circulatory system, consisting of a central organ (the heart pump) and blood vessels located throughout the body. Thanks to the constant work of the human heart, blood continuously circulates through the vascular bed, providing all cells with oxygen and nutrition. The living pump of our body makes at least a hundred thousand contractions every day. How the human heart works, what its operating principle is, what the numbers of the main indicators indicate - these questions are of interest to many people who care about their health.
general information
Knowledge about the structure and function of the human heart accumulated gradually. The beginning of cardiology as a science is considered to be 1628, when the English physician and naturalist Harvey discovered the basic laws of blood circulation. Subsequently, all the basic information was obtained about the anatomy of the heart and blood vessels, the human circulatory system, which is still used today.
The living “perpetual motion machine” is well protected from damage due to its favorable location in the human body. Every child knows where a person’s heart is – in the chest on the left, but this is not entirely true. Anatomically, it occupies the middle part of the anterior mediastinum - this is closed space in the chest between the lungs, surrounded by the ribs and sternum. The lower part of the heart (its apex) is slightly displaced in left side, the remaining departments are in the center. In rare cases, there is an abnormal location of the heart in a person with a displacement in right side(dextrocardia), which is often combined with a mirror placement in the body of all unpaired organs (liver, spleen, pancreas, etc.).
Everyone has their own ideas about what a person’s heart looks like; usually they differ from reality. Externally, this organ resembles an egg, slightly flattened on top and pointed at the bottom, with large vessels adjacent on all sides. The shape and size may vary depending on the gender, age, body type and health status of the man or woman.
People say that the size of the heart can be approximately determined by the size of your own fist - medicine does not argue with this. Many people are interested in knowing how much a human heart weighs? This indicator depends on age and gender.
The weight of an adult's heart reaches an average of 300 g, and in women it may be slightly less than in men.
There are pathologies in which deviations of this value are possible, for example, with myocardial growth or expansion of the heart chamber. In newborn children, its weight is about 25 g, the most significant growth rates are observed during the first 24 months of life and at 14-15 years, and after 16 years the indicators reach adult values. The ratio of the mass of an adult’s heart to the total body mass in men is 1:170, in women 1:180.
Anatomical and physiological features
To understand the structure of the human heart, let's first look at it from the outside. We see a cone-shaped hollow muscular organ, to which branches of large vessels of the human circulatory system approach from all sides, like tubes or hoses to a pump. This is the living pump of our body, consisting of several functional sections (chambers), separated from each other by partitions and valves. Every eighth grade student knows how many chambers there are in the human heart. For those who missed biology classes, we repeat - there are four of them (2 on each side). What are these heart chambers and what is their role in the circulatory system:
- The cavity of the right atrium receives two vena cava (inferior and superior), carrying oxygen-free blood collected from all over the body, which then enters the lower section (right ventricle), bypassing the tricuspid (or tricuspid) heart valve. Its valves open only during compression of the right atrium, then close again, preventing blood from flowing in a retrograde direction.
- The right heart ventricle pumps blood into the common pulmonary trunk, which then divides into two arteries that carry oxygen-free blood to both lungs. In the human body, these are the only arteries through which venous rather than arterial blood flows. In the lungs, the process of oxygenation of blood takes place, after which it is delivered to the left atrium through two pulmonary veins (again, an interesting exception - the veins carry oxygen-rich blood).
- In the cavity of the left atrium there are pulmonary veins, delivering arterial blood here, which is then pumped into the left ventricle through the cusps of the mitral valve. In the heart of a healthy person, this valve opens only in the direction of direct blood flow. In some cases, its doors may bend in reverse side and let some of the blood from the ventricle back into the atrium (this is mitral valve prolapse).
- The left ventricle plays a leading role; it pumps blood from the pulmonary (lesser) circulation to the systemic circle through the aorta (the most powerful vessel in the human circulatory system) and its numerous branches. The ejection of blood through the aortic valve occurs during systolic compression of the left ventricle; during diastolic relaxation, another portion from the left atrium enters the cavity of this chamber.
Internal structure
The heart wall consists of several layers represented by different tissues. If you mentally draw its cross-section, you can highlight:
- the inner part (endocardium) is a thin layer of epithelial cells;
- the middle part (myocardium) is a thick muscle layer that, through its contractions, provides the main pumping function of the human heart;
- outer layer - consists of two leaves, the inner one is called the visceral pericardium or epicardium, and the outer fibrous layer is called the parietal pericardium. Between these two leaflets there is a cavity with serous fluid, which serves to reduce friction during heart contractions.
If we consider the internal structure of the heart in more detail, it is worth noting several interesting formations:
- chords (threads of tendons) - their role is to attach the valves of the human heart to the papillary muscles on the inner walls of the ventricles, these muscles contract during systole and prevent retrograde blood flow from the ventricle to the atrium;
- heart muscles - trabecular and comb formations in the walls of the heart chambers;
- interventricular and interatrial septa.
In the middle part of the interatrial septum, the oval window sometimes remains open (it functions only in the fetus in utero, when there is no pulmonary circulation). This defect is considered a minor developmental anomaly; it does not interfere with normal life, unlike congenital defects of the interatrial or interventricular septum, in which normal blood circulation is significantly impaired. Whatever blood fills the right half of the human heart (venous), this will also enter the left side during systole, and vice versa. As a result, the load on certain parts increases, which over time leads to the development of heart failure. The blood supply to the myocardium is carried out by two coronary arteries of the heart, which are divided into numerous branches, forming the coronary vascular network. Any disruption of the patency of these vessels leads to ischemia (oxygen starvation of the muscle), up to tissue necrosis (infarction).
Cardiac performance indicators
If all departments work in a balanced manner, the contractility of the myocardium is not impaired, and the vessels of the heart are well-passed, then a person does not feel its beating. While we are young, healthy and active, we do not think about how the human heart works. However, once chest pain, shortness of breath or interruptions appear, the work of the heart immediately becomes noticeable. What indicators should everyone know:
- The value of the heart rate (HR) is from 60 to 90 beats per minute, the heart should beat at rest in an adult; if it beats more than 100 times, it is tachycardia, less than 60 is bradycardia.
- Stroke volume of the heart (systolic volume or CO) is the volume of blood that is released into the human circulatory system as a result of one contraction of the left ventricle; normally it is 60-90 ml at rest. The higher this value, the lower the heart rate and the greater the body’s endurance during exercise. This indicator is especially important for professional athletes.
- Cardiac output (minute volume of blood circulation) is defined as CO multiplied by heart rate. Its value depends on many factors, including the level of physical fitness, body position, temperature environment etc. The norm at rest while lying down for men is 4-5.5 liters per minute, for women it is 1 liter per minute less.
A person has a unique organ thanks to which he lives, works, loves. Taking care of the heart is all the more valuable, and it begins with studying the features of its structure and function. In fact, the cardiac engine is not so eternal; its work is negatively affected by many factors, some of which a person can control, others he can completely exclude in order to ensure a long and fulfilling life.
The heart is a muscular organ in humans and animals that pumps blood through blood vessels.
Functions of the heart - why do we need a heart?
Our blood provides the entire body with oxygen and nutrients. In addition, it also has a cleansing function, helping in the removal of metabolic waste.
The function of the heart is to pump blood through blood vessels.
How much blood does the human heart pump?
The human heart pumps from 7,000 to 10,000 liters of blood in one day. This amounts to approximately 3 million liters per year. That works out to 200 million liters over a lifetime!
The amount of blood pumped within a minute depends on the current physical and emotional load - the greater the load, the more blood the body requires. So the heart can conduct from 5 to 30 liters through itself in one minute.
The circulatory system consists of about 65 thousand vessels, their total length is about 100 thousand kilometers! Yes, we didn't make a mistake.
Circulatory system
The human cardiovascular system is formed by two circles of blood circulation. With each heartbeat, blood moves in both circles at once.
Pulmonary circulation
- Deoxygenated blood from the superior and inferior vena cava enters the right atrium and then into the right ventricle.
- From the right ventricle, blood is pushed into the pulmonary trunk. The pulmonary arteries carry blood directly to the lungs (up to the pulmonary capillaries), where it receives oxygen and releases carbon dioxide.
- Having received enough oxygen, the blood returns to the left atrium of the heart through the pulmonary veins.
Systemic circulation
- From the left atrium, blood moves into the left ventricle, from where it is subsequently pumped through the aorta into the systemic circulation.
- After going through a difficult path, the blood again arrives through the vena cava to the right atrium of the heart.
Normally, the amount of blood pushed out of the ventricles of the heart is the same with each contraction. Thus, an equal volume of blood simultaneously enters the greater and lesser circulation.
What is the difference between veins and arteries?
- Veins are designed to transport blood to the heart, and the job of arteries is to supply blood in the opposite direction.
- In veins, blood pressure is lower than in arteries. Accordingly, the walls of arteries are more elastic and dense.
- Arteries saturate “fresh” tissue, and veins take away “waste” blood.
- In the case of vascular damage, arterial or venous bleeding can be distinguished by its intensity and the color of the blood. Arterial - strong, pulsating, beating like a “fountain”, the color of the blood is bright. Venous - bleeding of constant intensity (continuous flow), the color of the blood is dark.
The weight of a human heart is only about 300 grams (on average 250 grams for women and 330 grams for men). Despite its relatively low weight, it is undoubtedly the main muscle in the human body and the basis of its life activity. The size of the heart is indeed approximately equal to a human fist. Athletes' hearts can be one and a half times larger than those of the average person.
Anatomical structure
The heart is located in the middle of the chest at the level of 5-8 vertebrae.
Normally, the lower part of the heart is located mostly in the left side of the chest. There is a variant of congenital pathology in which all organs are mirrored. It is called transposition of internal organs. The lung, next to which the heart is located (normally the left one), is smaller in size relative to the other half.
The back surface of the heart is located near the spinal column, and the front surface is reliably protected by the sternum and ribs.
The human heart consists of four independent cavities (chambers) divided by partitions:
- two upper ones - the left and right atria;
- and two lower ones - the left and right ventricles.
The right side of the heart includes the right atrium and ventricle. The left half of the heart is represented, respectively, by the left ventricle and atrium.
The inferior and superior vena cava enter the right atrium, and the pulmonary veins enter the left atrium. From right ventricle the pulmonary arteries (also called the pulmonary trunk) emerge. From left ventricle the ascending aorta rises.
The heart has protection from overstretching and other organs, which is called the pericardium or pericardial sac (a kind of membrane in which the organ is enclosed). It has two layers: an outer dense, durable connective tissue called fibrous membrane of the pericardium and internal ( serous pericardium).
Thus, the heart itself consists of three layers: epicardium, myocardium, endocardium. It is the contraction of the myocardium that pumps blood through the vessels of the body.
The walls of the left ventricle are approximately three times larger than the walls of the right! This fact is explained by the fact that the function of the left ventricle is to push blood into the systemic circulation, where the resistance and pressure are much higher than in the pulmonary circulation.
The device of heart valves
Special heart valves allow you to constantly maintain blood flow in the correct (unidirectional) direction. The valves alternately open and close, either letting blood through or blocking its path. Interestingly, all four valves are located along the same plane.
Between the right atrium and the right ventricle is located tricuspid (tricuspid) valve. It contains three special leaflet plates that, during contraction of the right ventricle, can provide protection from the reverse flow (regurgitation) of blood into the atrium.
Works in a similar way mitral valve, only it is located on the left side of the heart and is bicuspid in its structure.
Aortic valve prevents the reverse flow of blood from the aorta into the left ventricle. Interestingly, when the left ventricle contracts, the aortic valve opens as a result of blood pressure on it, so it moves into the aorta. After which, during diastole (the period of relaxation of the heart), the reverse flow of blood from the artery promotes the closure of the valves.
Normally, the aortic valve has three leaflets. The most common congenital heart abnormality is bicuspid aortic valve. This pathology occurs in 2% of the human population.
Pulmonary valve at the moment of contraction of the right ventricle, it allows blood to flow into the pulmonary trunk, and during diastole it does not allow it to flow in the opposite direction. It also consists of three doors.
Cardiac vessels and coronary circulation
The human heart requires nutrition and oxygen, just like any other organ. The vessels that supply (nourish) the heart with blood are called coronary or coronary. These vessels branch from the base of the aorta.
The coronary arteries supply the heart with blood, and the coronary veins remove deoxygenated blood. Those arteries that are located on the surface of the heart are called epicardial. Subendocardial arteries are called coronary arteries hidden deep in the myocardium.
Most of the blood outflow from the myocardium occurs through three cardiac veins: large, middle and small. Forming the coronary sinus, they flow into the right atrium. The anterior and small veins of the heart deliver blood directly to the right atrium.
Coronary arteries are divided into two types - right and left. The latter consists of the anterior interventricular and circumflex arteries. The great cardiac vein branches into the posterior, middle and small veins of the heart.
Even absolutely healthy people have their own unique characteristics of coronary circulation. In reality, the vessels may look and be located differently than shown in the picture.
How does the heart develop (form)?
Pulse path
This system ensures automatism of the heart - excitation of impulses generated in cardiomyocytes without an external stimulus. In a healthy heart, the main source of impulses is the sinoatrial (sinus) node. He is the leader and blocks the impulses from all other pacemakers. But if any disease occurs that leads to sick sinus syndrome, then other parts of the heart take over its function. Thus, the atrioventricular node (automatic center of the second order) and the His bundle (AC of the third order) are able to activate when the sinus node is weak. There are cases when secondary nodes enhance their own automaticity and when normal operation sinus node.
Sinus node located in the upper posterior wall of the right atrium in close proximity to the mouth of the superior vena cava. This node initiates pulses at a frequency of approximately 80-100 times per minute.
Atrioventricular node (AV) located in the lower part of the right atrium in the atrioventricular septum. This septum prevents the impulse from propagating directly into the ventricles, bypassing the AV node. If the sinus node is weakened, then the atrioventricular node will take over its function and begin to transmit impulses to the heart muscle at a frequency of 40-60 contractions per minute.
Next, the atrioventricular node passes into His bundle(atrioventricular bundle divided into two legs). The right leg rushes towards the right ventricle. The left leg is divided into two more halves.
The situation with the left bundle branch has not been fully studied. It is believed that the left leg with fibers from the anterior branch rushes to the anterior and lateral wall of the left ventricle, and the posterior branch supplies fibers to the posterior wall of the left ventricle and the lower parts of the lateral wall.
In case of weakness of the sinus node and atrioventricular block, the His bundle is capable of creating impulses at a speed of 30-40 per minute.
The conducting system deepens and further branches into smaller branches, eventually moving into Purkinje fibers, which penetrate the entire myocardium and serve as a transmission mechanism for contraction of the ventricular muscles. Purkinje fibers are capable of initiating impulses at a frequency of 15-20 per minute.
Exceptionally trained athletes can have normal resting heart rates down to the lowest recorded figure of just 28 beats per minute! However, for the average person, even one leading a very active lifestyle, a heart rate below 50 beats per minute may be a sign of bradycardia. If your heart rate is this low, you should be examined by a cardiologist.
Heartbeat
A newborn's heart rate may be around 120 beats per minute. As a person gets older, the pulse stabilizes between 60 and 100 beats per minute. Well trained athletes we're talking about about people with well-trained cardiovascular and respiratory systems) have a pulse of 40 to 100 beats per minute.
Controls heart rhythm nervous system- the sympathetic strengthens contractions, and the parasympathetic weakens.
Cardiac activity, in to a certain extent, depends on the content of calcium and potassium ions in the blood. Other biologically active substances also contribute to the regulation of heart rhythm. Our heart may begin to beat faster under the influence of endorphins and hormones released when listening to our favorite music or kissing.
In addition, the endocrine system can have a significant impact on the heart rhythm - both the frequency of contractions and their strength. For example, the release of the well-known adrenaline by the adrenal glands causes an increase in heart rate. The hormone with the opposite effect is acetylcholine.
Heart sounds
One of the most simple methods diagnosing heart disease is by listening to the chest using a stethoscope (auscultation).
In a healthy heart, during standard auscultation, only two heart sounds are heard - they are called S1 and S2:
- S1 is the sound heard when the atrioventricular (mitral and tricuspid) valves close during ventricular systole (contraction).
- S2 - the sound heard when the semilunar (aortic and pulmonary) valves close during diastole (relaxation) of the ventricles.
Each sound consists of two components, but to the human ear they merge into one due to the very short period of time between them. If in normal conditions During auscultation, additional tones become audible, this may indicate some kind of disease of the cardiovascular system.
Sometimes additional abnormal sounds may be heard in the heart, called a heart murmur. As a rule, the presence of murmurs indicates some kind of heart pathology. For example, noise can cause blood to flow back in the opposite direction (regurgitation) due to malfunction or damage to a valve. However, noise is not always a symptom of a disease. To clarify the reasons for the appearance of additional sounds in the heart, it is worth doing echocardiography (ultrasound of the heart).
Heart diseases
It is not surprising that the number of cardiovascular diseases is increasing in the world. The heart is a complex organ that actually rests (if it can be called rest) only in the intervals between heartbeats. Any complex and constantly working mechanism itself requires the most careful treatment and constant prevention.
Just imagine what a monstrous burden falls on the heart given our lifestyle and low-quality, abundant nutrition. Interestingly, mortality from cardiovascular diseases is also quite high in high-income countries.
The huge amounts of food consumed by the population of wealthy countries and the endless pursuit of money, as well as the associated stress, destroy our hearts. Another reason for the spread of cardiovascular diseases is physical inactivity - catastrophically low physical activity that destroys the entire body. Or, on the contrary, an illiterate passion for heavy physical exercise, often occurring against the background of which people do not even suspect and manage to die right during “health” activities.
Lifestyle and heart health
The main factors that increase the risk of developing cardiovascular diseases are:
- Obesity.
- High blood pressure.
- Increased blood cholesterol levels.
- Physical inactivity or excessive physical activity.
- Abundant, low-quality food.
- Depressed emotional condition and stress.
Make reading this great article a turning point in your life - give up bad habits and change your lifestyle.
in women 1:180. And many more interesting facts about the human body can be found
How much does the average human heart weigh?
The heart is a muscular organ in humans and animals that pumps blood through blood vessels.
Functions of the heart - why do we need a heart?
Our blood provides the entire body with oxygen and nutrients. In addition, it also has a cleansing function, helping in the removal of metabolic waste.
The function of the heart is to pump blood through blood vessels.
How much blood does the human heart pump?
The human heart pumps several liters of blood in one day. This amounts to approximately 3 million liters per year. That works out to 200 million liters over a lifetime!
The amount of blood pumped within a minute depends on the current physical and emotional load - the greater the load, the more blood the body requires. So the heart can conduct from 5 to 30 liters through itself in one minute.
The circulatory system consists of about 65 thousand vessels, their total length is about 100 thousand kilometers! Yes, we didn't make a mistake.
Circulatory system
Circulatory system (animation)
The shape is determined by age, gender, physique, health, and other factors. In simplified models, it is described by a sphere, ellipsoids, and the intersection figures of an elliptical paraboloid and a triaxial ellipsoid. The measure of elongation (factor) of the shape is the ratio of the largest longitudinal and transverse linear dimensions of the heart. With a hypersthenic body type, the ratio is close to one, and with an asthenic body type, it is about 1.5. The length of the heart of an adult varies from 10 to 15 cm (usually 12-13 cm), width at the base 8-11 cm (usually 9-10 cm) and anteroposterior size 6-8.5 cm (usually 6.5-7 cm) . The average heart weight in men is 332 g (from 274 to 385 g), in women - 253 g (from 203 to 302 g).
In relation to the midline of the body of the heart, it is located asymmetrically - about 2/3 to the left of it and about 1/3 to the right. Depending on the direction of the projection of the longitudinal axis (from the middle of its base to the apex) on the anterior chest wall, transverse, oblique and vertical positions of the heart are distinguished. The vertical position is more common in people with a narrow and long chest, the transverse position is more common in people with a wide and short chest. The heart can independently provide venous return only in vessels currently located above the top of the atria, i.e. by gravity, by gravitational forces (Ivan Golovanov “New theory of blood circulation and health”, Moscow, 2001, p. 48). Performing pumping functions in the circulatory system, the heart constantly pumps blood into the arteries. Simple calculations show that over the course of 70 years, the heart of an average person performs more than 2.5 billion beats and pumps 250 million liters of blood.
On these pages you can find out:
How much does a person's soul weigh?
How much does a tiger weigh
How much does the Tsar Bell weigh?
How much does the Olympic torch weigh?
How much does a leopard weigh?
23. During life, the human small intestine is about 2.5 meters long. After his death, when the muscles of the intestinal wall relax, its length reaches 6 meters.
24. A person has approximately 2 million sweat glands. The average adult loses 540 calories with every liter of sweat. Men sweat about 40% more than women.
25. The right lung of a person holds more air than the left.
26. An adult takes approximately one breath (and one breath) per day.
27. Over the course of a lifetime, the female body reproduces 7 million eggs.
28. The human eye is capable of distinguishing 0 shades of color.
29. There are parabacteria in the human mouth.
30. Papaphobia is the fear of the Pope!
With each contraction, about 70 g of blood is ejected from the heart; per day it pumps at least 9450 liters of blood. On average, an adult's heart beats 70-75 times per minute. Heart rate depends on several factors, including the size of the body. In general, the larger the organism, the lower the heart rate. Thus, a woman’s heart makes 6-8 more contractions per minute than a man’s heart. In a newborn, the heart rate can reach 130 beats per minute.
The hair can be stretched to 1/5 of its length, and after that it returns to its original state.
The strength of the hair is comparable to aluminum and can withstand a load of 100 to 200 g.
Hair is hygroscopic, that is, it is able to absorb moisture - this is due to the structure of the hair.
Hair is resistant to weak acids, but does not tolerate alkaline compounds well.
Hair can accumulate certain substances, which allows it to be used as an identifier.
The lifespan of hair is different: on average, men have 2 years on their heads, and women have 4-5 years.
Redheads have the thickest hair, but less hair than others.
Black hair is the largest of all, and can be 3 times thicker than blonde hair.
The baby's first hairs appear in the womb, at about 4-5 months of pregnancy.
Hair grows at an average rate of 0.4 mm per day.
As you age, your hair becomes shorter and thinner.
Hair is mainly composed of proteins.
The hair follicle has three phases of life: anagen (hair growth phase), catagen (transition phase), telogen (resting phase).
Women are less likely to go bald than men because women's hair roots sit 2 millimeters deeper in the skin than men's.
How much blood does the heart pump?
5 liters of blood circulate throughout the entire cardiovascular system of an adult. With each contraction, the heart pushes blood into the arteries. Approximately 12 strokes are enough to fill, for example, a standard liter bag. These numbers are correct at rest. During physical activity, the volume of blood pumped increases several times. With maximum physical exertion - 4-5 times and with each blow more than 200 ml of blood is released into the arteries.
Can a person live without a heart?
In the absence of heart contractions, after 3-5 minutes, loss of consciousness immediately occurs and the gradual extinction of all vital functions. The heart has no duplicates! Nature “took care” of creating numerous paired organs for humans and only left the heart alone. This means that nature has created a perfect and reliable design that ensures the function is performed in natural conditions for the body.
Section. Two people: an experienced one and a beginner. The coach gives them intense work (crossfit, running, sparring, iron, etc. no matter what). But in an experienced person, the heart is trained and has a stretched volume of 1,000 - 1,200 ml. And the newcomer has a heart with a volume of 600 ml. Problem: what will happen? Answer: An experienced person’s heart rate will rise to 130 and he will complete the workout without any problems with benefits for the heart. But for a beginner, the heart rate will jump to... He will be red and out of breath. “Come on!” shouts the coach. "More!". And the beginner’s heart gradually dies at this time, causing micro-infarctions due to the diastole effect. A beginner does not train his heart, but ruins it, earning myocardial dystrophy. And I see this regularly in many sections.
80% of the human body's heat leaves the head.
The average human head weighs 3.6 kg.
Anatomy and physiology of the human heart
Our body is a complex structure consisting of individual components (organs and systems), the full functioning of which requires constant supply of nutrition and disposal of decay products. This work is performed by the circulatory system, consisting of a central organ (the heart pump) and blood vessels located throughout the body. Thanks to the constant work of the human heart, blood continuously circulates through the vascular bed, providing all cells with oxygen and nutrition. The living pump of our body makes at least a hundred thousand contractions every day. How the human heart works, what its operating principle is, what the numbers of the main indicators indicate - these questions are of interest to many people who care about their health.
general information
Knowledge about the structure and function of the human heart accumulated gradually. The beginning of cardiology as a science is considered to be 1628, when the English physician and naturalist Harvey discovered the basic laws of blood circulation. Subsequently, all the basic information was obtained about the anatomy of the heart and blood vessels, the human circulatory system, which is still used today.
The living “perpetual motion machine” is well protected from damage due to its favorable location in the human body. Every child knows where a person’s heart is – in the chest on the left, but this is not entirely true. Anatomically, it occupies the middle part of the anterior mediastinum - this is a closed space in the chest between the lungs, surrounded by the ribs and sternum. The lower part of the heart (its apex) is slightly shifted to the left side, the remaining parts are in the center. In rare cases, there is an abnormal location of the heart in a person with a displacement to the right side (dextrocardia), which is often combined with a mirror placement of all unpaired organs in the body (liver, spleen, pancreas, etc.).
Everyone has their own ideas about what a person’s heart looks like; usually they differ from reality. Externally, this organ resembles an egg, slightly flattened on top and pointed at the bottom, with large vessels adjacent on all sides. The shape and size may vary depending on the gender, age, body type and health status of the man or woman.
People say that the size of the heart can be approximately determined by the size of your own fist - medicine does not argue with this. Many people are interested in knowing how much a human heart weighs? This indicator depends on age and gender.
The weight of an adult's heart reaches an average of 300 g, and in women it may be slightly less than in men.
There are pathologies in which deviations of this value are possible, for example, with myocardial growth or expansion of the heart chamber. In newborn children, its weight is about 25 g, the most significant growth rates are observed during the first 24 months of life and infancy, and after 16 years the indicators reach adult values. The ratio of the mass of an adult’s heart to the total body mass in men is 1:170, in women 1:180.
Anatomical and physiological features
To understand the structure of the human heart, let's first look at it from the outside. We see a cone-shaped hollow muscular organ, to which branches of large vessels of the human circulatory system approach from all sides, like tubes or hoses to a pump. This is the living pump of our body, consisting of several functional sections (chambers), separated from each other by partitions and valves. Every eighth grade student knows how many chambers there are in the human heart. For those who missed biology classes, we repeat - there are four of them (2 on each side). What are these heart chambers and what is their role in the circulatory system:
- The cavity of the right atrium receives two vena cava (inferior and superior), carrying oxygen-free blood collected from all over the body, which then enters the lower section (right ventricle), bypassing the tricuspid (or tricuspid) heart valve. Its valves open only during compression of the right atrium, then close again, preventing blood from flowing in a retrograde direction.
- The right heart ventricle pumps blood into the common pulmonary trunk, which then divides into two arteries that carry oxygen-free blood to both lungs. In the human body, these are the only arteries through which venous rather than arterial blood flows. In the lungs, the process of oxygenation of blood takes place, after which it is delivered to the left atrium through two pulmonary veins (again, an interesting exception - the veins carry oxygen-rich blood).
- In the cavity of the left atrium there are pulmonary veins that deliver arterial blood here, which is then pumped into the left ventricle through the cusps of the mitral valve. In the heart of a healthy person, this valve opens only in the direction of direct blood flow. In some cases, its valves can bend in the opposite direction and allow part of the blood from the ventricle to pass back into the atrium (this is mitral valve prolapse).
- The left ventricle plays a leading role; it pumps blood from the pulmonary (lesser) circulation to the systemic circle through the aorta (the most powerful vessel in the human circulatory system) and its numerous branches. The ejection of blood through the aortic valve occurs during systolic compression of the left ventricle; during diastolic relaxation, another portion from the left atrium enters the cavity of this chamber.
Internal structure
The heart wall consists of several layers represented by different tissues. If you mentally draw its cross-section, you can highlight:
- the inner part (endocardium) is a thin layer of epithelial cells;
- the middle part (myocardium) is a thick muscle layer that, through its contractions, provides the main pumping function of the human heart;
- outer layer - consists of two leaves, the inner one is called the visceral pericardium or epicardium, and the outer fibrous layer is called the parietal pericardium. Between these two leaflets there is a cavity with serous fluid, which serves to reduce friction during heart contractions.
If we consider the internal structure of the heart in more detail, it is worth noting several interesting formations:
- chords (threads of tendons) - their role is to attach the valves of the human heart to the papillary muscles on the inner walls of the ventricles, these muscles contract during systole and prevent retrograde blood flow from the ventricle to the atrium;
- heart muscles - trabecular and comb formations in the walls of the heart chambers;
- interventricular and interatrial septa.
In the middle part of the interatrial septum, the oval window sometimes remains open (it functions only in the fetus in utero, when there is no pulmonary circulation). This defect is considered a minor developmental anomaly; it does not interfere with normal life, unlike congenital defects of the interatrial or interventricular septum, in which normal blood circulation is significantly impaired. Whatever blood fills the right half of the human heart (venous), this will also enter the left side during systole, and vice versa. As a result, the load on certain parts increases, which over time leads to the development of heart failure. The blood supply to the myocardium is carried out by two coronary arteries of the heart, which are divided into numerous branches, forming the coronary vascular network. Any disruption of the patency of these vessels leads to ischemia (oxygen starvation of the muscle), up to tissue necrosis (infarction).
Cardiac performance indicators
If all departments work in a balanced manner, the contractility of the myocardium is not impaired, and the vessels of the heart are well-passed, then a person does not feel its beating. While we are young, healthy and active, we do not think about how the human heart works. However, once chest pain, shortness of breath or interruptions appear, the work of the heart immediately becomes noticeable. What indicators should everyone know:
- The value of the heart rate (HR) is from 60 to 90 beats per minute, the heart should beat at rest in an adult; if it beats more than 100 times, it is tachycardia, less than 60 is bradycardia.
- Stroke volume of the heart (systolic volume or CO) is the volume of blood that is released into the human circulatory system as a result of one contraction of the left ventricle, normally at rest. The higher this value, the lower the heart rate and the greater the body’s endurance during exercise. This indicator is especially important for professional athletes.
- Cardiac output (minute volume of blood circulation) is defined as CO multiplied by heart rate. Its value depends on many factors, including the level of physical fitness, body position, ambient temperature, etc. The norm at rest while lying down for men is 4-5.5 liters per minute, for women it is 1 liter per minute less.
A person has a unique organ thanks to which he lives, works, loves. Taking care of the heart is all the more valuable, and it begins with studying the features of its structure and function. In fact, the cardiac engine is not so eternal; its work is negatively affected by many factors, some of which a person can control, others he can completely exclude in order to ensure a long and fulfilling life.
How much does an adult human heart weigh? What is the size of a human heart?
What is the weight of a human heart?
How much does a human heart weigh?
The heart of any person is approximately equal to the size of his fist. The weight of an adult human heart is 220-260 g, and the heart weight ratio is
(to total body weight) is equal to 1:170 for men,
for women – 1:180. And many more interesting facts about the human body can be found
Weight of a baby's heart at birth. After 8 months it becomes twice as large. An adult man's heart weighs 300 grams, a woman's heart weighs several grams. Well, I think everyone knows that the size of a person’s heart is equal to the size of his fist.
The average weight of an adult’s heart is g. Heart length cm, width cm, height (thickness) cm. The thickness of the ventricles: left - 0.8 - 1 cm, right - about 0.5 cm.
How much does a human heart weigh?
Usually the size of a human heart is compared to the size of his fist, which is approximately true - the heart is the same size as a clenched human palm. An athlete has a larger heart; constant physical activity leads to the growth of all muscle groups, which include the heart muscle. The weight of an adult human heart is equal to the weight of two to three medium apples.
The average weight of a man's heart is 332 grams, a woman's gram.
The heart is a powerful and uninterrupted engine in the human body, the main function of which is to pump blood from the venous vessels to the arterial ones. This is probably the only organ whose work a person feels and hears. When we are worried, the heart beats frightfully fast, when we are happy, it is exciting, and when a bright feeling settles in it - love, it just begins to sing!
Despite its small size (the length of the muscular organ is from 10 to 15 cm, the width is 8-11 cm), the heart copes with a colossal load. It pumps about 7,000 liters of blood per day. If you place this amount of liquid medium in standard 200-liter barrels, you get 35 containers, and in one minute of operation a powerful heart pump can completely fill a bath with blood. The principle of the heart is the rhythmic contraction of the heart muscle. The heart cavity is divided into two atria and two ventricles. The right part refers to the “arterial” heart, the left is venous. Venous vessels deliver “waste” blood to the heart, and oxygen-enriched blood moves through the arteries. Veins have a thinner wall and the pressure in them is much less than in the arteries. This feature helps to distinguish the type of bleeding if they rupture: dark blood flows out of the vein in a continuous stream, while in arterial bleeding bright red, scarlet blood is ejected with pulsating movements.
When measuring blood pressure, two indicators are recorded: upper and lower. The upper pressure is called systolic, at this moment the heart muscle contracts. The second indicator is diastolic pressure; the heart is in a relaxed state during this period. Normal blood pressure readings are 120/80 mm Hg. , a deviation to a greater extent can cause a disease called hypertension, to a lesser extent - hypotension.
How the heart works
The formation of cardiac tissue begins in the embryonic stage of fetal development. The child receives nutrition through the mother's placenta, but in order for its own organs to begin to grow and develop, nutrients must be delivered to every cell of the body. Therefore, the heart is the very first functional organ that begins to grow and form in a tiny organism. By the 22nd day of pregnancy, the embryo has its first heartbeat; by the 26th day, its own blood circulation is formed in the growing body. At birth, the baby's heart is no larger than a strawberry.
The baby's heart becomes similar to the heart of an adult by the tenth week of development: at this moment, septa and heart valves appear in it.
After the tiny “motor” begins its responsible work, the heart rate is almost the same as that of an adult: beats per minute. By the seventh week of development, the heart “accelerates” to beats and during a CTG study, the expectant mother hears its rapid beating. At birth, the pulse “calms down” to the normal beats per minute.
The entire work cycle of the heart muscle consists of two phases: systole and diastole. At the moment of relaxation of the heart muscle, the atria and partly the ventricles are filled with blood. Then the atria contract and the liquid medium is pushed into the ventricles, while the veins at the mouth are compressed, which prevents blood from flowing into them. After this, the atria relax, the ventricles contract and blood is pushed into the aorta through the left ventricle and into the pulmonary artery through the right. The mitral and tricuspid valves at this moment block the return of blood to the atrium. After this, the cycle repeats again and so on throughout a person’s life.
The heart rate is “set” by the sympathetic nervous system. The release of adrenaline produced by the adrenal glands into the blood increases the strength and number of heart contractions, and the production of acetycholine has the opposite effect.
Listening to heart sounds is done using a stethoscope, invented by the French doctor Rene Laennec (the aesculapian was guided by the fact that it is quite difficult to hear the heart of ladies with a magnificent bust, simply by pressing the ear to the chest). Another invention is related to the human heart - this is the second hand on a watch, the patent belongs to the English doctor John Flower, he introduced an innovation to make it convenient to count a person’s pulse.
The heart rate in women is higher than in men, with an average of 78 beats per minute. For men it is beats per minute. Although it is believed that the heart beats continuously, this is not entirely true. The period when the heart works is the contraction of the heart muscle; in a relaxed state, the heart begins a period of rest.
This explains the efficiency of the human motor; nature has arranged its activity in such a way that the heart has the opportunity to take a break from its hard and constant work.
It is known that no engine will work without fuel. For the heart, oxygen is such a “fuel”. In order to work for a day, the heart muscle will need 130 liters of pure oxygen, its average consumption per minute is 2.5 liters. One heartbeat is equal to the amount of energy it takes to lift an object weighing 200 grams to a height of one meter. The energy generated by a human engine in a day would be enough for a passenger car to travel 32 kilometers, and in a month the heart can produce such an amount of energy that if used, a person of average weight can easily be lifted to the top of the highest mountain - Chomolungmas. In a lifetime, a person could travel to the moon and back, using the resources of his own heart!
The heart is not just an important organ in the human body, it is a symbol of love. The ancient Egyptians believed that the ring finger was connected by a special channel to the heart muscle, hence the custom of putting a wedding ring on it. In Russia, a monument to the heart was erected; it is located in the city of Perm in the courtyard of the Heart Institute. The granite giant weighing about four tons symbolizes the fiery red human heart, like a steppe poppy. The weight of a human heart determines his age, height, and physical fitness. And yet, this is not only a muscle that triggers physiological processes in the human body, it is a small and capacious place where human feelings, experiences and secrets are stored.
How much does the average human heart weigh?
All people have different weights and different heights, and accordingly, the sizes and weights of their internal organs, for example, the heart, are different. How much does a person’s heart weigh on average, or rather, what are the limits of its weight for people of different builds?
Medical and anatomical statistics state that the human heart can weigh from 250 to 350 grams. Of course, a woman’s heart weighs less than a man’s; the average heart weight for the fairer sex is 253 grams, and for men – 332.
human heart
human heart
In the Beauty and Health section, to the question How much does an adult’s heart weigh? set by author User deleted best answer Are they men or women?
The weight of a newborn’s heart averages 23–37 g;
by the 8th month the weight of the heart doubles,
by the 2nd–3rd year of life it triples.
Average heart weight at ages 20–40
reaches 300 g in men,
for women – 270 g.
Heart weight ratio
to total body weight is equal to 1:170 for men,
External structure of the heart (front view).
9. anterior interventricular groove
11.superior vena cava
12.aorta (ascending aorta)
13.place of transition of epicardium to pericardium
15.left common carotid artery
16.left subclavian artery
What should you do if you find a child’s heart?
An adult has about 5 liters of blood. ..The heart of an average adult weighs (as much as 2-3 apples)
gram. I’m telling you this as a future doctor.
Make a fist with your hand and shake it. And you will understand!
A baby's heart usually beats faster than an adult's. The heart of a newborn baby, weighing no more than 20 g and the size of a strawberry, beats at a frequency of 120 beats per minute. By age 10, the heart rate slows to 90 beats. The average adult's heart weighs 300 g (the equivalent of 2-3 apples) and beats at about 70 beats per minute in men and about 80 in women.
With each contraction, the heart pushes blood into the arteries. About 12 strokes are enough to fill a standard quart orange juice carton with blood. In a minute, the heart can fill a whole bath with blood, and in an hour it pumps almost 350 liters - this is enough to fill the gas tanks of several cars.
However, all these figures are correct if the person is at rest. As soon as you start moving, your heart rate immediately increases, and with it the volume of blood pumped. During intense physical exertion, the heart contracts at a frequency of over 150 beats per minute, pumping more than 200 ml of blood with each beat. Such a hard worker will manage to fill a bathtub with blood in just four minutes!
Interesting facts about the human heart
The heart is the organ responsible for pumping blood through the vessels of the circulatory system. One of the main functions of the human heart is to saturate the body with oxygen and nutrients. The stability of all systems depends on the health of the main organ.
This review is about the heart of man. As you read, you will learn: on which side the heart is located, how much it weighs, as well as other interesting facts that you definitely didn’t know about.
For additional information, you can contact the portal specialists. Consultations are provided free of charge 24 hours a day.
Structure of the heart
Do you know which side the heart is on? Most will answer - on the left, and will be right, but partially. The human heart has a four-chamber structure and is located in the central region of the chest and is slightly shifted to the left. The outer walls of the heart are surrounded by a special membrane called the pericardium or bursa. The space between the organ and the pericardium is filled with fluid, which moisturizes the heart and reduces friction during its contraction.
The four-chambered human heart has sections - right and left, each of which is equipped with an atrium and a ventricle. In a normal state, the right and left sections do not interact with each other, but at the same time ensure stable blood flow. Pathology is considered to be the presence of through passages through which blood flows from one to another.
The sections, in turn, have atria, which communicate with the ventricles through small openings. Along the edges of the holes there are special valves: on the right side - tricuspid, on the left - bicuspid.
These valves are responsible for where the blood is directed. From each ventricle the aorta originates, which also has valves in the form of three leaves (pockets). Each leaf is turned into a vessel through which blood is carried.
Many of our readers actively use a well-known technique based on natural ingredients, discovered by Elena Malysheva. We recommend that you check it out.
By the way, a heart weighs about 300g: a woman’s heart weighs 250g, a man’s heart weighs 330g. But, despite the fact that the main organ weighs so little, human life completely depends on it. In everyday life there is an opinion that the human heart is the size of a fist. Doctors completely agree with this. However, in people involved in sports, the organ can be 1.5 times larger than the average size. The affected organ is often larger than normal.
An interesting fact is that there are people who have a mirror arrangement of organs, i.e. four-chambered heart on the right side of the chest. Due to the non-standard location, the entire structure of the body of such people is unique. Doctors assure that such a “pathology,” although unusual, does not pose any danger to humans.
Circulation
We have found out where a person’s heart is located. Now let's consider main function of this organ - blood circulation. Of course, everyone understands that without this function a person would not be able to live fully. The blood circulation function is carried out in two circles, called large and small.
- Large, originating in the left stomach and ending in the right section of the atrium. Its task is to supply blood to all organs, incl. lungs.
- The small one originates from the stomach in the right section and ends in the left atrium. The main task is to ensure gas exchange in the alveoli of the upper respiratory tract.
Each contraction of an organ causes blood to move simultaneously in both circles. In this case, pulmonary circulation produces blood without oxygen, which flows through the veins first into the atrium and then into the ventricle.
From the ventricle, the blood flow passes to the pulmonary trunk, where it flows strictly to the capillary system. At this point an exchange occurs - the blood gives off carbon dioxide and takes in oxygen. And at the same time, the systemic circulation promotes flow from the atrium to the ventricle. The path that blood takes through the veins is not easy, but with normal functioning of the organ, it reaches the right atrium of the four-chambered heart. Thus, blood circulation is carried out in the human body.
Properties
They don’t look at the fact that the organ weighs little and its size is equal to a fist; the heart is capable of working under various loads. Let's look at the most interesting properties:
- Autonomy, i.e. the heart contracts from impulses that originate in it.
- Excitability. This is the name for the property of a muscle to respond to a variety of stimuli, both from the physical and chemical environment. Such reactions are accompanied by changes in the properties of organ tissues.
- Conductivity. Doctors note that a rhythm is created in this organ due to an electrical impulse. This pace is set in special cells - pace makers.
- Myocardial refractoriness. This feature of the heart makes it possible to block the reaction to pathogens, thereby the organ continues to contract in operating mode.
Doctors call disruption of the rhythm of contractions “flickering.” In other words, the heart begins to contract out of sync, which can lead to death.
Having carefully studied Elena Malysheva’s methods in the treatment of tachycardia, arrhythmia, heart failure, stenacordia and general improvement of the body, we decided to offer it to your attention.
The functions of the heart, its structure, size and how much it weighs were found out exactly. We should touch on interesting facts that most people have never heard of.
For those interested unique properties body, the following list of facts proven by doctors around the world will be interesting:
- Blood circulation occurs approximately 100 thousand times per day. The distance that blood travels is approximately 100 thousand km.
- An interesting study conducted by doctors showed that the heart contracts more than 34 million times per year.
- An incredible fact: over the course of a year, the heart supplies the body with 3 million liters of blood.
- How much energy is spent on the work of the heart? One contraction, think about it, spends energy equivalent to lifting a 400g load. to a height of one meter.
- Do you know how many cells are supplied with blood by the main organ? 75 trillion!
- During the day, the main organ produces energy that would be enough to cover 32 km. way by car. How much in a lifetime? – Stop flying to the moon and return to Earth.
- The knock that we hear is formed when the heart valves close.
- After conducting several studies, doctors discovered an interesting fact: in a minute, in normal mode, the organ pumps from 5 liters to 30.
- The average heartbeat is 72 beats per minute, or about one hundred thousand per year. How much for a life? The answer from scientists is 3 billion times.
- Fact - the heart, separated from the body with sufficient oxygen levels, will continue to contract due to self-sufficient impulses.
- Doctors took measurements and revealed how many beats per minute the child had in the womb - two times higher than that of his mother or 140 times.
- The organ stores 5% of the blood supply. About 20% goes to the central nervous system and brain, while the kidneys receive 22%.
- The first beat of a child’s heart occurs only four weeks after the fertilization of the egg.
- Another Scientific research revealed the fact that the baby has only a glass of blood in his entire body.
- A drug such as cocaine, which, by the way, is not recommended for use by doctors and the Ministry of Health, as well as the Criminal Code of the Russian Federation, can cause myocardial infarction even in a completely healthy person. This fact has been proven and lies in the fact that the drug directly affects the activity of muscle contractions of the heart, thereby causing spasm of the arteries.
- Have you ever thought about how long it takes for blood to enter a particular organ? The facts say - 6 seconds. from the heart to the lungs and back again; 8 sec. the path to the brain and back; 16 sec. to your toes and also come back. Lightning fast, isn't it?! And this is in a calm state.
- The stethoscope (a medical instrument for listening to the rhythm of the heart) was invented by a doctor who found it inconvenient to “listen” to the heart of busty women.
We presented the most interesting facts that became known to society thanks to the scientific research of doctors.
“A tree is strong in its roots, but a man is strong in his heart.” This expression reflects the whole essence of human life. The main organ responsible for the functionality of the body is the heart, which is the basis for reliable health and for long years life.
- Do you often experience discomfort in the heart area (stabbing or squeezing pain, burning sensation)?
- You may suddenly feel weak and tired.
- The pressure is constantly fluctuating.
- There is nothing to say about shortness of breath after the slightest physical exertion...
- And you have been taking a bunch of medications for a long time, going on a diet and watching your weight.
Better read what Elena Malysheva says about this. For several years I suffered from arrhythmia, ischemic heart disease, angina pectoris - squeezing, stabbing pain in the heart, irregular heart rhythms, pressure surges, swelling, shortness of breath even with the slightest physical exertion. Endless tests, visits to doctors, and pills did not solve my problems. BUT thanks simple recipe, heart pain, blood pressure problems, shortness of breath - all this is in the past. I feel great. Now my attending physician is surprised how this is so. Here is a link to the article.
The shape of the heart is not the same from person to person. It is determined by age, gender, physique, health, and other factors. In simplified models, it is described by a sphere, ellipsoids, and the intersection figures of an elliptical paraboloid and a triaxial ellipsoid. The measure of elongation (factor) of the shape is the ratio of the largest longitudinal and transverse linear dimensions of the heart. With a hypersthenic body type, the ratio is close to one, and with an asthenic body type, it is about 1.5. The length of the heart of an adult varies from 10 to 15 cm (usually 12-13 cm), width at the base 8-11 cm (usually 9-10 cm) and anteroposterior size 6-8.5 cm (usually 6.5-7 cm) . The average heart weight in men is 332 g (from 274 to 385 g), in women - 253 g (from 203 to 302 g).
In relation to the midline of the body, the heart is located asymmetrically - about 2/3 to the left of it and about 1/3 to the right. Depending on the direction of the projection of the longitudinal axis (from the middle of its base to the apex) on the anterior chest wall, transverse, oblique and vertical positions of the heart are distinguished. The vertical position is more common in people with a narrow and long chest, the transverse position is more common in people with a wide and short chest. The heart can independently provide venous return only in vessels located at the moment above the top of the atria, that is, by gravity, by gravity. Performing pumping functions in the circulatory system, the heart constantly pumps blood into the arteries. Simple calculations show that over the course of 70 years, the heart of an average person performs more than 2.5 billion beats and pumps 250 million liters of blood.
Structure of the heart
The heart is located on the left side of the chest in the so-called pericardium, which separates the heart from other organs. The heart wall consists of three layers - the epicardium, myocardium and endocardium. The epicardium consists of a thin (no more than 0.3-0.4 mm) plate of connective tissue, the endocardium consists of epithelial tissue, and the myocardium consists of cardiac striated muscle tissue.
The heart consists of four separate cavities called chambers: left atrium, right atrium, left ventricle, right ventricle. They are separated by partitions. The right atrium contains the hollow veins, and the left atrium contains the pulmonary veins. From the right ventricle and left ventricle emerge, respectively, the pulmonary artery (pulmonary trunk) and the ascending aorta. The right ventricle and left atrium close the pulmonary circulation, the left ventricle and right atrium close the systemic circle. The heart is located in the lower part of the anterior mediastinum, most of its anterior surface is covered by the lungs with the inflowing sections of the vena cava and pulmonary veins, as well as the outflowing aorta and pulmonary trunk. The pericardial cavity contains a small amount of serous fluid.
The wall of the left ventricle is approximately three times thicker than the wall of the right ventricle, since the left must be strong enough to push blood into the systemic circulation for the entire body (the resistance of blood in the systemic circulation is several times greater, and the blood pressure is several times greater higher than in the pulmonary circulation).
There is a need to maintain blood flow in one direction, otherwise the heart could fill with the same blood that was previously sent into the arteries. Responsible for the flow of blood in one direction are the valves, which at the appropriate moment open and close, allowing blood to pass through or blocking it. The valve between the left atrium and the left ventricle is called the mitral valve or bicuspid valve because it consists of two leaflets. The valve between the right atrium and the right ventricle is called the tricuspid valve - it consists of three petals. The heart also contains the aortic and pulmonary valves. They control the flow of blood from both ventricles.
Circulation
Coronary circulation
Each cell of the heart muscle must have a constant supply of oxygen and nutrients. The heart’s own blood circulation, that is, the coronary circulation, is responsible for this process. The name comes from 2 arteries, which, like a crown, entwine the heart. The coronary arteries arise directly from the aorta. Up to 20% of the blood ejected by the heart passes through the coronary system. Only such a powerful portion of oxygenated blood ensures the continuous operation of the life-giving pump of the human body.
Heart cycle
Work of the heart
A healthy heart contracts and unclenches rhythmically and without interruption. There are three phases in one cardiac cycle:
- The atria, filled with blood, contract. In this case, blood is pumped through the open valves into the ventricles of the heart (at this time they remain in a state of relaxation). Contraction of the atria begins at the point where the veins flow into it, so their mouths are compressed and blood cannot flow back into the veins.
- Contraction of the ventricles occurs with simultaneous relaxation of the atria. The tricuspid and bicuspid valves that separate the atria from the ventricles rise, slam shut, and prevent blood from returning to the atria, while the aortic and pulmonary valves open. Contraction of the ventricles forces blood into the aorta and pulmonary artery.
- A pause (diastole) is a relaxation of the entire heart, or a short period of rest for this organ. During a pause, blood from the veins enters the atria and partially flows into the ventricles. When a new cycle begins, the blood remaining in the atria will be pushed into the ventricles - the cycle will repeat.
One cycle of the heart lasts about 0.85 seconds, of which the time of contraction of the atria is only 0.11 seconds, the time of contraction of the ventricles is 0.32 seconds, and the longest is the rest period, lasting 0.4 seconds. The heart of an adult at rest works in the system at about 70 cycles per minute.
Automaticity of the heart
A certain part of the heart muscle specializes in issuing control signals to the rest of the heart in the form of appropriate electrical impulses. These parts of muscle tissue are called the excitatory conduction system. Its main part is the sinoatrial node, called the pacemaker, located on the vault of the right atrium. It controls the heart rate by sending regular electrical impulses. The electrical impulse travels through pathways in the atrium muscle to the atriogastric node. The excited node sends an impulse further to individual muscle cells, causing them to contract. The excitatory conduction system ensures the rhythmic functioning of the heart through synchronized contraction of the atria and ventricles.
Regulation of the heart
The work of the heart is regulated by the nervous and endocrine systems, as well as by Ca and K ions contained in the blood. The work of the nervous system over the heart is to regulate the frequency and strength of heart contractions (the sympathetic nervous system causes increased contractions, the parasympathetic nervous system weakens them). The work of the endocrine system on the heart is to release hormones that increase or decrease heart contractions. The main gland that secretes hormones that regulate the functioning of the heart is the adrenal gland. They secrete the hormones adrenaline and acetylcholine, whose functions in relation to the heart correspond to the functions of the sympathetic and parasympathetic systems. The same work is performed by Ca and K ions, respectively.
Electrical and acoustic phenomena
When the heart (like any muscle) works, electrical phenomena, which cause the appearance electromagnetic field around a working organ. The electrical activity of the heart can be recorded using special electrodes placed on certain areas of the body. Using an electrocardiograph, an electrocardiogram (ECG) is obtained - a picture of changes over time in the potential difference on the surface of the body. ECG plays an important role in diagnosing heart attack and other diseases of the cardiovascular system.
Acoustic phenomena called heart sounds can be heard by placing an ear or stethoscope on the chest. Each cardiac cycle is normally divided into 4 tones. The ear hears the first 2 with each contraction. The longer and lower one is associated with the closure of the bicuspid and tricuspid valves, the shorter and higher one is associated with the closure of the aortic and pulmonary artery valves. Between the first and second tone there is a phase of ventricular contraction.
Notes
see also
Links
Heart in Wiktionary | |
Heart on Wikimedia Commons |
Wikimedia Foundation. 2010.
See what “Human Heart” is in other dictionaries:
Wed. I have a lot of silver for feasts, for conversations in red words, for fun of wine. Koltsov. Song. Wed. I didn’t drink beer before I retired: Ask, the whole block will tell you. Now, out of grief, when I get drunk, it’s as if I’m having fun. A.E. Izmailov. Drunkard. Wed. Wine... ...
Wine gladdens the human heart. Wed. I have a lot of silver for feasts, for conversations of red words, for fun of wine. Koltsov. Song. Wed. I didn’t drink before I retired: Ask, the whole block will tell you. Now I get drunk out of grief, It’s as if... ...
The womb of a wolf is insatiable, and the heart of a man is insatiable. Wed. Is it enough? “Not yet!” It wouldn't crack. "Don't be afraid." Look, you have become Croesus. “A little more, a little more: At least throw in a handful.” Hey, that's enough! Look, the bag is already crawling apart. “One more pinch!” But here... ... Michelson's Large Explanatory and Phraseological Dictionary (original spelling)
Wed. Is it enough? Not yet! It wouldn't crack. Don't be afraid. Look, you have become Croesus. Another, a little more: At least throw in a handful. Hey, that's enough! Look, the sum is already crawling apart. One more pinch! But then the wallet broke through... Krylov. Fortune and the Beggar. Wed. Or it burns... ... Michelson's Large Explanatory and Phraseological Dictionary