Heart function

The heart performs a number of important functions in the body, providing blood flow and supporting vital functions. Here are the main functions of the heart:

1. Pumping Blood: The primary function of the heart is to pump blood through the blood vessels throughout the body. When the heart contracts (systole), it ejects blood into the aorta, and from the aorta, blood flows into the arterial vessels, providing oxygen and nutrients to all organs and tissues.
2. Oxygenation of organs and tissues: The heart provides oxygen transport from the lungs to organs and tissues where oxygen is needed for vital functions. This is accomplished by pumping oxygenated blood from the cardiac lung to the systemic circulation.
3. Providing nutrition to organs and tissues: The blood pumped by the heart also contains nutrients such as glucose, amino acids and fats, which are essential for energy supply and growth of all cells in the body.
4. Removal of metabolic waste products: The heart helps transport metabolic waste products, such as carbon dioxide and metabolic wastes, from tissues to organs where they can be eliminated from the body through the lungs and kidneys.
5. Blood pressure regulation: The heart controls blood pressure by keeping it at a certain level. This is important to ensure normal blood flow and organ function.
6. Providing immune defense: The blood pumped by the heart contains white blood cells that participate in the body's immune defense, fighting infections and diseases.

The heart performs these functions continuously, providing vital processes in the body. Any disruption of its function can lead to serious diseases and complications.

Cardiac contractile function

It is the heart's ability to contract (or systolic function) during each cardiac cycle to push blood from the ventricles into the arteries and allow blood flow in the body. This function is important for providing oxygen and nutrients to the body's vital organs and tissues.

The contractile function of the heart includes the following aspects:

1. Systolic phase: During the systolic phase of the cardiac cycle, the ventricles of the heart contract, causing blood to be pushed into the arterial vessels. In this phase, blood is ejected from the left ventricle into the aorta and from the right ventricle into the pulmonary arteries.
2. Systolic volume: This is the amount of blood that is ejected from each ventricle into the arteries during systole. Systolic volume depends on various factors, including the volume of blood that fills the ventricles during the diastolic phase and the strength of myocardial (heart muscle) contraction.
3. Systolic function: The systolic function of the heart determines the ability of the heart to perform its primary task of maintaining blood flow in the body. This function is assessed using parameters such as ejection fraction (EF), which is the percentage of systolic blood volume to diastolic blood volume, etc., as well as other parameters such as ejection fraction (EF).

The contractile function of the heart can be impaired due to various causes such as heart disease, arrhythmias, myocardial infarction, cardiac hypertrophy and other conditions. This can lead to heart failure, where the heart is unable to contract effectively and provide adequate blood flow in the body. Treatment for these conditions may include drug therapy, surgery, and other methods to restore the contractile function of the heart.

The pumping function of the heart

It is the heart's ability to pump blood efficiently through the blood vessels, allowing blood to circulate in the body. This function involves moving blood from the atria to the ventricles and then pumping it out of the ventricles into the arteries so that the blood reaches all the organs and tissues of the body. The pumping function of the heart is key to keeping the body alive, as it ensures that oxygen and nutrients are delivered to the tissues and organs.

Cardiac pumping function is assessed using a variety of parameters including:

1. Stroke volume (SV): This is the amount of blood ejected from each ventricle of the heart during one systolic phase (one heartbeat). The stroke volume depends on the volume of blood that fills the ventricles during the diastolic phase and the force of contraction of the heart muscle.
2. Heart rate (pulse): This is the number of times your heart beats per minute. Normal heart rate depends on a person's age and physical activity.
3. Minute volume (cardiac output, CO): This is the total amount of blood ejected from the heart into the aorta in one minute. It is calculated as the product of stroke volume and heart rate.
4. Ejection fraction (EF): This is the percentage ratio of stroke volume to diastolic volume that reflects the efficiency of ventricular contraction of the heart. Normal EF is usually around 55-70%.

Decreased pumping function of the heart can occur in a variety of conditions such as heart failure, myocardial infarction, arrhythmias, and other cardiac abnormalities. These conditions may require medication, surgery, or other methods to restore or maintain normal pumping function of the heart.

The pumping function of the heart

Related to its ability to pump blood from the ventricles of the heart to the arterial system of the body. This function is to create the force needed to move blood into the arteries and further distribute it throughout the body.

Key aspects of the pumping function of the heart include:

1. Systoliccontraction: During the systolic phase of the cardiac cycle, which corresponds to ventricular contraction, the force necessary to push blood from the left stomach into the aorta (systemic circulation) and from the right stomach into the pulmonary artery (pulmonary circulation) is generated. This phase is called systole and is usually the shortest part of the cardiac cycle.
2. Cardiac output: The amount of blood ejected from the left stomach into the aorta during one systole is called cardiac output. Cardiac output is defined as the volume of blood that leaves the left stomach during each systolic phase. This parameter can vary depending on physical activity and other factors.
3. Arterial pressure: The force that the heart uses to push blood into the arteries creates arterial pressure. This pressure is necessary to ensure that blood can reach all tissues and organs of the body. It is important that blood pressure is kept within a normal range to ensure optimal blood flow.

The pumping function of the heart is important to the functioning of the body because it ensures that oxygen and nutrients are constantly and reliably delivered to the cells and organs. Any impairment of this function can lead to serious medical problems such as hypoxia (lack of oxygen) and other complications.

Systolic heart function

Describes the heart's ability to contract (or systolic contractions) to push blood from the left ventricle into the aorta and from the right ventricle into the pulmonary artery. This process occurs during the systolic phase of the cardiac cycle.

The main parameters assessing cardiac systolic function include:

1. Systolic volume: This is the amount of blood that is pushed out of the ventricles into the aorta and pulmonary artery during the systolic phase. It is measured in milliliters and is usually about 70 ml.
2. Systolic ejection fraction (SEF): This is the percentage ratio of systolic volume to ventricular filling volume before the systolic phase. The SFV reflects the efficiency of the heart in expelling blood. The normal value of EFV is usually around 55-70%.
3. Systolic blood pressure: This is the maximum pressure in the arteries that is reached during the systolic phase when the heart pushes blood into the aorta. This parameter is measured in millimeters of mercury (mmHg) and is an important indicator for assessing heart function and vascular health.

Cardiac systolic function assessment systems, such as echocardiography (cardiac ultrasound), can be used to determine parameters of systolic function, including SFV and systolic volume. Decreased systolic function of the heart can be associated with a variety of heart conditions, such as chronic heart failure, and may require medical intervention and treatment.

The systolic function of the heart is important to ensure adequate blood flow to the organs and tissues of the body. Any disturbance in this function can lead to serious cardiac problems and deterioration of the patient's general condition.

Diastolic function of the heart

Related to its ability to relax and fill with blood during the diastolic phase of the cardiac cycle. Diastole is the period when the heart expands and fills with blood before the next contraction (systole). To understand the diastolic function of the heart, it is important to know the following aspects:

1. Ventricular relaxation: During the diastolic phase of the cardiac cycle, the ventricles (left and right) dilate and relax to receive blood returning from the lungs (left stomach) and body (right stomach).
2. Blood filling: Diastolic function involves the active process of filling the ventricles with blood, which begins with the opening of the valves (mitral and tricuspid valves) and ends with their closing before systole begins. This stage is called "diastolic filling".
3. Ventricular pressure: During the diastolic phase, the pressure in the ventricles decreases, allowing blood to flow freely into them from the atria.
4. Filling rate: The rate at which the ventricles fill with blood during the diastolic phase can be an important indicator of diastolic function. Rapid filling (relaxation) of the ventricles is a sign of normal diastolic function.
5. Atrialpressure: Atrial pressure, as well as atrial function, also affects diastolic function because the atria must pump blood efficiently to the ventricles.

Pathologic changes in diastolic function may include diastolic dysfunction, which is manifested by impaired ability of the heart to relax and fill with blood during the diastolic phase. This condition can be caused by various factors such as myocardial hypertrophy, valve disease, arterial hypertension, etc. Diagnosis and treatment of diastolic dysfunction requires medical evaluation and, in some cases, medication and lifestyle changes to maintain normal diastolic function of the heart.

Functions of the heart valves

The valves of the heart perform important functions in maintaining normal cardiovascular function. Their main functions include:

1. Regulation of blood flow: The heart valves control the flow of blood within the heart, allowing blood to move in only one direction. They prevent blood from flowing backwards, allowing it to move from one part of the heart to another: from the atria to the ventricles (mitral and tricuspid valves) and from the ventricles to the aorta and pulmonary arteries (aortic and pulmonary valves).
2. Pressure Maintenance: Valves help maintain optimal blood pressure within the heart and in large arteries such as the aorta and pulmonary arteries, which is necessary for efficient blood flow.
3. Backflow protection: One of the most important aspects of valve function is to prevent regurgitation or backflow of blood. Valves provide a tight seal so that blood cannot flow back to the previous section of the heart.
4. Optimizing ventricular filling: The valves help control how much blood fills each ventricle of the heart before it contracts. This ensures optimal filling and efficient ejection of blood during ventricular contraction.
5. Maintaining normal gas exchange: By controlling the flow of blood and its distribution to all organs and tissues, valves also promote gas exchange in the lungs, allowing oxygen to be carried to the cells and carbon dioxide to be removed from the body.
6. Maintaining normal cardiac function: Normal valve function is essential to ensure that the heart works safely and efficiently, maintaining its ability to pump blood and provide vital bodily functions.

When the structure or function of the heart valves is compromised, heart failure, backflow of blood, and other serious heart problems can occur. These conditions may require surgery to reconstruct the valves or replace them.

Functions of the heart muscle

The muscles of the heart, or myocardium, perform the primary function in the organ of contraction and relaxation, which allows the heart to function as a pump, pumping blood throughout the body. The main functions of the heart muscle include:

1. Contraction: The muscles of the heart are able to contract in a synchronized and coordinated manner that allows the ventricles of the heart to eject blood into the arteries. This process is called systole and ensures that blood flow is maintained and oxygen and nutrients are delivered to organs and tissues.
2. Relaxation: After each contraction, the muscles of the heart relax to fill with blood from the atria again. This process is called diastole. Myocardial relaxation allows the myocardium to prepare for the next contraction and the re-release of blood.
3. Circulatory support: The muscles of the heart provide constant blood flow in the body by pumping blood through the arterial vessels and back through the venous vessels. This allows oxygen and nutrients to be delivered to the cells and carbon dioxide and metabolic waste to be removed.
4. Blood pressure regulation: The heart regulates blood pressure to keep it at an optimal level. This is important for normal blood flow and organ function.
5. Maintaining the immune system: Blood pumped through the heart contains white blood cells, which play an important role in the body's defense against infection and disease.
6. Involvement in hormonal responses: Cardiac myocardium can respond to hormones and neurotransmitters, which can affect cardiac contractile function and blood flow.
7. Adaptation to physical activity: The muscles of the heart can adapt to physical activity by increasing the frequency and strength of contractions to provide additional blood flow and oxygen to muscles and tissues during exercise.

The myocardium is one of the most important muscles in the body, and its normal function is critical to sustaining life. Heart disease or myocardial dysfunction can lead to serious consequences and requires medical intervention and treatment.

Functions of the ventricles of the heart

The ventricles of the heart are the two lower cavities of the heart that play a key role in blood flow. The heart has two ventricles: the left ventricle and the right ventricle. Each has its own specific functions:

1. Left ventricle(left ventricle): The left ventricle is the more powerful and muscular of the two ventricles. Its primary function is to pump oxygen-rich blood from the left atrium to the aorta. When the left stomach contracts (systole), it advances the oxygen-rich blood into the aorta, and from there it is distributed throughout the body to supply oxygen and nutrients to organs and tissues. The left stomach has thicker muscles to handle the high pressure created when it contracts to pump blood into the aorta.
2. Rightstomach (right ventricle): The right stomach is responsible for pumping blood from the right atrium to the pulmonary artery. This is carbon dioxide-rich blood that is returned from the body to the lungs for oxygenation. When the right stomach contracts (systole), it advances blood into the pulmonary artery, and from there it travels to the lungs, where oxygen and carbon dioxide gases are exchanged. The lungs enrich the blood with oxygen and remove carbon dioxide, which is then exhaled.

Thus, the functions of the ventricles of the heart are related to pumping blood to the major arteries of the body (left stomach) and to the pulmonary artery for gas exchange (right stomach). The heart ventricles work in a coordinated sequence to ensure continuous blood flow and delivery of oxygen and nutrients to tissues and organs, which is necessary to sustain life.

Functions of the atria of the heart

The atria (or atria) of the heart perform important functions in the cardiac system, playing a role in the cardiac cycle and ensuring proper blood flow. Here are the main functions of the heart's atria:

1. Blood Reception: The atria work as reservoirs to receive blood from the venous system. The right atrium (right atrium) receives venous blood, rich in carbon dioxide and poor in oxygen, from the body through the superior and inferior vena cava. The left atrium (left atrium) receives oxygen-rich blood from the lungs through the four pulmonary veins.
2. Contraction and Blood Direction: The atria contract to push blood into the ventricles (ventricles) of the heart during the systolic phase of the cardiac cycle. The blood will then be further directed into the aorta from the left ventricle and into the pulmonary arteries from the right ventricle.
3. Synchronization and control: The atria play an important role in synchronizing the heart. They create electrical signals that initiate contraction of the ventricles. This ensures that blood moves in the heart and to the body's organs and tissues in the correct sequence.
4. Overloadprotection: The atria act as "buffers" to temporarily store blood in the event of higher blood flow than the ventricles can handle. This helps prevent the ventricles from overloading the ventricles with blood.
5. Maintaining blood flow during times of increased activity: When the heart is physicallyactive or stressed, it may increase its rate of contraction. The atria may increase their contribution to the contractions to allow for increased blood flow.
6. Ensuring normal heart function in the different phases of the cardiac cycle: The atria are involved in the creation of electrical impulses and control the spread of electrical activity in the heart, ensuring proper sequential contraction of the different parts of the heart.

The atria play a key role in the efficient operation of the cardiovascular system, and their functions are closely related to the ventricles and arteries of the heart. They help maintain adequate blood circulation, adapt to different conditions and provide oxygen and nutrients to the body's organs and tissues.

Vascular functions of the heart

The blood vessels of the heart play an important role in the proper functioning of the cardiovascular system. Here are the main functions of the vessels of the heart:

1. Blood Transport: The vessels of the heart, including arteries and veins, serve to transport blood containing oxygen and nutrients between the heart and other tissues and organs of the body. Arteries carry blood away from the heart, and veins carry blood back to the heart.
2. Oxygen extraction: The vessels of the heart, particularly the coronary arteries, provide oxygen and nutrients to the heart itself. The heart, as a muscle, needs enough oxygen to perform its function.
3. WasteBlood Removal: The veins of the heart carry waste blood and metabolic waste products away from the heart and other tissues so that it can be directed to the lungs and kidneys for filtration and purification.
4. Blood pressure regulation: Arteries and arterioles are important for blood pressure regulation. Vessels can constrict (vasoconstriction) or dilate (vasodilation), which affects the resistance to blood flow and the pressure in the blood vessels.
5. Protection against backflow of blood: The vessels of the heart have valves that prevent backflow of blood. Valves in the heart (e.g. Mitral and tricuspid valves) and valves in larger vessels (e.g. Aortic and pulmonary valves) ensure unidirectional blood flow.
6. Keeping warm: Vessels in the skin play a role in the body's thermoregulation by regulating dilation and constriction to retain body heat during cold periods or dissipate heat during hot weather.
7. Involvement in the immune system: Blood vessels also participate in the immune system by transporting white blood cells and antibodies to sites of infection or inflammation.

The vessels of the heart, as well as all vessels of the body, perform important functions to maintain the vital activity of organs and tissues, providing their blood supply and participating in the regulation of various physiological processes.

Functions of the veins of the heart

The veins of the heart fulfill an important role in the cardiac system by allowing blood to circulate within the heart itself. The main functions of the veins of the heart include:

1. Collection of blood from organs and tissues: The veins of the heart collect deoxygenated (oxygen-poor) blood from the body's organs and tissues, including muscle, skin, and other structures. This blood contains waste carbon dioxide and metabolic waste that needs to be removed from the body.
2. Transportation of blood to the atria of the heart: Collected blood from different parts of the body enters the right and left atria of the heart through veins. The right atrium receives blood from the systemic veins and the left atrium receives blood from the pulmonary veins.
3. Maintaining Blood Flow: The veins of the heart play an important role in ensuring continuous blood flow within the heart. They temporarily store blood until it is pumped to the ventricles of the heart and on to the aorta and pulmonary arteries for further distribution throughout the body.
4. Blood volume regulation: Veins can expand or contract to regulate the amount of blood flowing to the heart. This allows blood flow to be adapted to physical activity and other physiological needs of the body.
5. Involved in blood pressure regulation: Venous return, which is the amount of blood returning to the right atrium of the heart, can affect the total blood pressure in the body. Regulation of this process helps maintain normal blood pressure.

The veins of the heart are an integral part of the circulation and help to maintain the balance of blood and oxygen in the body. They work in concert with the arteries and heart valves to ensure efficient and reliable blood flow.

Cardiac conduction function

Responsible for the creation and propagation of electrical impulses in the heart that regulate its contractile activity. These impulses allow the heart to contract and relax synchronously, ensuring the correct rhythm and rate of heartbeats. Important elements of the heart's conducting system are:

1. CA node (sinoatrial node): This is the primary bundle of cells that generates electrical impulses and is located at the top of the right atrium. The CA node determines the heart's rate of contraction and serves as the heart's natural pacemaker.
2. The bundle of Hiss (atrioventricular node): The bundle of Hiss is located in the lower part of the right atrium, near the interventricular septum. It receives electrical impulses from the CA node and slows them down before transmitting them to the ventricles, allowing for proper coordination of atrial and ventricular contractions.
3. The bundle of Hiss and Purkinje fibers: These structures are part of the ventricular myocardium and are responsible for transmitting electrical impulses to the myocardium, causing ventricular contraction. Purkinje fibers are highly conductive.
4. Ventricular myocardium: The ventricular myocardium is composed of myocytes that contract in response to electrical impulses transmitted by the conduction system of the heart. This contraction of the ventricles allows blood to be pushed out into the arteries and allows blood to circulate.

Abnormalities in the conduction function of the heart can lead to arrhythmias (irregular heart rhythm), blockages (blocked transmission of impulses), and other cardiac abnormalities. Diagnosis and treatment of these conditions may require electrocardiography (ECG), electrophysiologic testing, drug therapy, pacemaker implantation, or other medical procedures.

Cardiac automaticity function

Related to its ability to generate and transmit electrical impulses to regulate heart muscle contractions. Cardiac automaticity ensures that the heart contracts rhythmically and in a coordinated manner without external influence. An important part of the automaticity system are specialized cells called pacymakers, which detect changes in electrochemical potential and initiate contractions.

The basic functions of cardiac automatism include:

1. Electrical impulse generation: Pacimakers such as the sinus node (the most important), atrioventricular node and ventricular pacimakers are capable of generating electrical impulses in a specific sequence and at a specific frequency. The sinus node usually generates the primary impulse that determines the basic rhythm of the heart.
2. Transmission of impulses: Electrical impulses generated by the pachymakers travel along special conductive pathways within the heart. This includes the atrioventricular node (AV node) and the bundle of Hiss. The transmission of impulses from the atria to the ventricles via the AV node ensures that the contractions of the upper and lower chambers of the heart are properly coordinated.
3. Heart rhythm regulation: Specialized pacymakers determine the rate of heartbeat, which is called the heart rhythm. The sinus node usually dictates a normal heart rhythm, which is approximately 60-100 beats per minute. However, if necessary, other pacymakers can take over the role of generating pulses if the sinus node is not performing its function properly.
4. Adaptation to change: The heart's automaticity allows the body to adapt to changes in physical activity, stress, temperature, and other factors. For example, when you exercise, the sinus node may increase its rate of contraction to ensure that there is enough blood flow to the working muscles.

The automatism function of the heart provides a stable and rhythmic blood circulation, which is necessary to ensure the vital activity of all organs and tissues of the body.

Regulation of heart function

Controlled through a complex system of autonomic nervous system and hormonal mechanisms. Here are the main aspects:

1. Autonomic Nervous System: The heart is regulated by two branches of the autonomic nervous system:
   • Thesympathetic system: Activation of the sympathetic nervous system leads to an increase in heart activity. The nerves of the sympathetic system release the neurotransmitter norepinephrine, which increases the heart rate, the strength of the heartbeat, and the rate of conduction of impulses in the heart. This prepares the body for physical activity and stressful situations.
   • Parasympathetic System: Activation of the parasympathetic nervous system causes the heart to slow down. The nerves of the parasympathetic system release acetylcholine, which decreases the heart rate and increases the function of the heart valves. This occurs, for example, at rest or during digestion.
2. Hormonal regulation: Hormones also play a role in regulating heart function. For example, adrenaline released in stressful situations increases cardiac activity. Adrenaline's antagonist hormone, adrenaline, acts in a vascular-cardiac manner and can decrease cardiac activity.
3. Feedback mechanisms: The heart also has feedback mechanisms that regulate its activity according to the body's needs. For example, when blood oxygen levels decrease, this can stimulate the heart to increase its rate of contraction to increase the flow of oxygen to the tissues.
4. Central Nervous System: The brain, and in particular the part of the brain called the cerebellum, plays a role in regulating the activity of the heart. The cerebellum controls the rate and rhythm of heartbeat.

Regulation of cardiac function is important for maintaining homeostasis of the organism and adaptation to different conditions. This system ensures the delivery of oxygen and nutrients to tissues and organs, which is necessary for normal vital activity of the organism.

Cardiac dysfunction

Heart dysfunction, also known as heart failure, is a serious medical condition in which the heart is unable to pump blood efficiently and provide the body with the necessary amount of oxygen and nutrients. This condition can develop gradually or suddenly and can be caused by a variety of reasons. Here are the main types of heart dysfunction:

1. Systolic dysfunction: This disorder is associated with impaired ability of the heart to contract (systolic function) and pump blood into arteries. It can be caused by damage to the myocardium (heart muscle) due to myocardial infarction, hypertension, alcohol or drug poisoning, and other factors.
2. Diastolic dysfunction: In this disorder, the heart has difficulty relaxing and filling with blood during diastole (heart relaxation). This is often due to thickening of the walls of the heart's ventricles (hypertrophy) or other structural changes.
3. Mixed dysfunction: Some patients may have combined systolic and diastolic cardiacdysfunction.
4. Valve disorders: Heart defects, such as stenosis (narrowing) or insufficiency (incomplete closure) of the valves, can lead to impaired heart function. Valve disease can be congenital or acquired.
5. Arrhythmias: Uncontrolled arrhythmias, such as atrial fibrillation (AF), can reduce the efficiency of heart contractions and lead to impaired heart function.
6. Myocardial ischemia: Lack of blood supply to the heart muscle due to atherosclerosis (narrowing of blood vessels) or thrombosis can cause heart dysfunction.

Symptoms of heart dysfunction may include shortness of breath, fatigue, swelling (swelling of the legs and ankles), palpitations, weakness and malaise. Treatment for cardiac dysfunction includes drug therapy, lifestyle changes, physical activity regimens, and, in some cases, surgery such as valve replacement or coronary bypass surgery. Cardiac dysfunction requires mandatory treatment and medical monitoring to prevent worsening of the condition and reduce the risk of complications.