Where is our heart located?

Our heart is located inside the rib cage, behind the breastbone (the board of faith), in a sac called the pericardium, and on the diaphragm muscle (respiratory muscle). Our heart can be roughly compared to a cone whose base extends to the right, back and up, and the apex to the left, forward and downward. The weight of the heart is about 220 g in women and 300 g in men.

What is the task of our heart?

All tissues in our body need oxygen and nutrients to survive. The transportation of these vital substances to the extreme points of our body is through the blood. The main function of the heart, which is largely composed of muscle tissue, is to circulate blood throughout the body. Our heart pumps approximately 8 tons of blood every day, by contracting an average of 70 times a minute, approximately 100,000 times a day. Therefore, it would not be wrong to say that our heart is at the center of our lives.

What is the structure of our heart, how does it pump blood?

Our heart has a four-chamber structure. It consists of two atria (auricles) and two ventricles (ventricles). Thanks to a wall structure between them, the heart chambers are divided into right and left halves. The atria are the upper chambers of the heart and are the first spaces where the blood brought to the heart by the veins is poured. While the right atrium is the space where the deoxygenated venous blood coming from the whole body is poured, the left atrium is the space where the blood returning to the heart after being oxygenated in the lungs is poured. The ventricles are the main pumping chambers of the heart. The task of the right ventricle is to pump the oxygen-poor blood coming to it through a valve (tricuspid valve) after being collected in the right atrium, to the lungs via the main pulmonary artery as a result of the opening of another valve (pulmonary valve). The task of the left ventricle is to pump the oxygen-rich blood, which is collected in the left atrium after being re-oxygenated in the lungs and coming to it through a valve (mitral valve), through the aorta, after the opening of another valve (aortic valve).

What is the main function of the valves in the heart?

Blood always flows in one direction in the heart, and it achieves this thanks to the one-way opening valves in the heart. Blood passing through a valve always flows forward because of the valve that closes when it wants to return.

How many valves are in our heart and where are they located?

There are four valves in the heart. The aortic valve is located between the left ventricle and the aorta. The pulmonary valve is located at the beginning of the main pulmonary artery (lung artery). The other two valves (tricuspid and mitral valves), also called atrioventricular valves, are located between the atria and ventricles. After the atria are filled with blood, the blood passes through these valves and flows into the ventricles. Contraction of the ventricles causes an increase in pressure. Thanks to the increased pressure, the inlet valves (atrioventricular valves) are closed and the backflow of blood towards the atria is prevented. On the other hand, high ventricular pressure also allows the outlet valves (aortic and pulmonary artery valves) to open so that blood can leave the heart. The right atrioventricular valve lies between the right atrium and the right ventricle and is called the tricuspid valve. The left atrioventricular valve is located between the left atrium and the left ventricle and is called the mitral valve.

What is the structure of the valves in our heart and how do they work?

Heart valves have thin leaflets called leaflets. The (atrioventricular) valves (tricuspid and mitral valves) between the atria and ventricles of the heart are similar to each other in the way they work. The tricuspid valve has three leaflets, while the mitral valve has two. These leaflets are firmly attached to a ring-like structure at their base. These leaflets move away from each other during the passage of blood, bringing the valve to the open position. During the contraction of the ventricles, the free edges of the ventricles move upwards in a way that they kiss each other, thus ensuring the closure of the valve. The leaflets are attached to the muscle groups (papillary muscles) in the ventricle with thread-like structures (chordae tendineae) coming out from the lower parts of their free ends. With the effect of increasing pressure during the contraction of the ventricles, the valves between the atria and the ventricles are closed and the backflow of blood to the atria is prevented. This normal working order is achieved thanks to the harmonious functioning of all cover and under cover structures. Any pathology that disrupts the functioning of these valve and sub-valvular structures (ring-like structure, leaflets, thread-like structures and papillary muscles) prevents the valve from opening and closing normally, leading to problems in the valves between the auricles and ventricles (mitral and tricuspid). Aortic and pulmonary valves are similar to each other in structure (both consist of three leaflets) and in the way they work. The aortic valve, located between the left ventricle and the aorta, opens towards the aorta, allowing the passage of blood when the pressure in the left ventricle exceeds the aortic pressure. When the left ventricle contracts and begins to relax again, the leaflets of the aortic valve close, preventing the blood pumped into the aorta from returning to the left ventricle. The pulmonary valve is located at the beginning of the main pulmonary artery (lung artery) and functions just like the aortic valve. As the right ventricle of the heart contracts, it opens when the increased pressure exceeds the main pulmonary artery pressure, and when the right ventricle begins to relax, it closes again to prevent blood from returning. Aortic valve and pulmonary valve diseases occur as a result of various diseases that prevent these valves from opening and closing normally.

What symptoms do heart valve diseases cause?

Depending on the severity of the problem (stenosis/insufficiency) in the heart valve, patients may not have any complaints, or severe complaints due to heart failure may occur. The most common complaints in patients are fatigue, palpitations (rhythm problems), shortness of breath, swelling in the legs, paralysis due to clots in various arteries in our body, and similar clinical pictures.

Can both stenosis and insufficiency coexist in a heart valve?

While there may be isolated stenosis or insufficiency in the heart valves, in some patients, both stenosis and insufficiency may be found together. If the problem that restricts the opening of a valve also restricts the closing of that valve, stenosis and insufficiency may coexist.

Can heart valve problems be congenital? Some of the heart valve diseases are congenital and some are acquired problems.

How is the decision of surgery made in heart valve problems?

Decisions on surgery for heart valve patients followed by our hospitals are made by the joint decision of the members of the "Heart Team", which is formed by specialist physicians from different branches. In this committee, after evaluating all aspects of the patients in detail, recommendations are made to the patient about the most appropriate treatment method. 

AORTIC VALVE DISEASES Where is the aortic valve located and what is its function? 

The aorta is the largest artery in our body and comes out of the left ventricle of our heart. The aortic valve is located between the left ventricle and the aorta. It normally consists of three leaflets. The blood passing between the leaflets of the aortic valve, which is opened as a result of the contraction of the left ventricle, is pumped forward with great pressure. When the contraction of the left ventricle is over, the leaflets of the valve close again, preventing the return of blood in the aorta. What does aortic stenosis mean? Stenosis in the outflow tract of the left ventricle may be below the aortic valve, at the valve level, or above the valve level. 95% of stenosis in adult patients is located at the level of the aortic valve. Normally, when the aortic valve is opened, an opening of about 3-4 cm2 emerges between the leaflets for blood to pass through. All diseases that prevent the healthy opening of the aortic valve leaflets cause stenosis in the aortic valve. A significant complaint may not be detected in the majority of patients until the aortic valve opening is 1 cm2, and if this opening is below 0.7 cm2, critical aortic valve stenosis is present. In aortic stenosis, the aortic valve area decreases by an average of 0.1-0.3 cm2 per year.

What is the cause of aortic valve stenosis?

There are two main causes of stenosis in the aortic valve. a. Rheumatic Causes: The cause of 30-40% of aortic valve stenosis in developed countries is the sequelae of acute rheumatic fever due to tonsil infection in childhood. During this period, the affected leaflets stick together over the years and serious stenosis occurs in the aortic valve due to calcification. This rate is higher in our country. b. Non-rheumatic causes: i. Congenital aortic stenosis: The most common cause of congenital aortic stenosis is that the aortic valve consists of two leaflets instead of three (bicuspid aortic valve). This disease is very common. Its incidence in the community is 0.9-2%. While these patients may lead a normal life throughout their lives, progressive calcification, aortic valve insufficiency or aortic vascular diseases may develop. Calcification on the lid usually occurs between the ages of 50-60 ii. Degenerative (age-related, atherosclerotic type, calcific type of unknown origin) aortic stenosis: It is aortic valve stenosis seen in advanced age, and there is advanced calcification in the leaflets of the valve. It mostly occurs between the ages of 70-80.

What happens in aortic valve stenosis?

As the stenosis in the aortic valve increases, the left ventricle of the heart begins to contract more strongly in order to pass the amount of blood needed by the body through this stenosis, and the muscle mass of the left ventricle increases 2-3 times (hypertrophy). This can be compared to a bodybuilder building more muscle by constantly increasing the weight he trains with. In this way, the stenosis in the aortic valve may not be asymptomatic for a long time, but if the ECO check is performed, it can be easily determined that there is a serious pressure difference between both sides of the stenosis.

What complaints are seen in aortic stenosis?

If aortic stenosis is not operated after the symptoms appear, the course of the disease is quite dramatic. The first sign is usually tiring quickly on exertion. Due to the increase in the muscle mass of the left ventricle, in these patients (even if there is no coronary artery disease), the blood carried by the coronary arteries begins to be insufficient and the patient may complain of chest pain (if the valve is not intervened, the average life expectancy is 5 years). Fainting may occur during exertion due to stenosis in the aortic valve (average life expectancy is 3 years if the valve is not intervened). Over time, the relaxation of the left ventricular cavity of the heart also begins to deteriorate. To cope with this situation, the left atrium begins to contract more strongly. The blood supply to the left ventricle becomes largely dependent on the contraction of the left atrium. A sudden rhythm problem (atrial fibrillation) that may develop in these patients may stop the contraction of the left auricle and lead to severe heart failure in the patient (if the valve is not intervened, the average life expectancy is 2 years). Can aortic valve stenosis cause sudden death? Aortic valve stenosis is the most deadly valvular disease. While the risk of sudden death is 5% in patients without complaints, the risk of sudden death may increase up to 20% in patients with complaints. AORTIC FAILURE What does aortic regurgitation mean? It is the condition in which blood flows backwards from the aorta into the left ventricle during the relaxation period of the left ventricle as a result of the aortic valve not closing well enough. Its severity is determined by the amount of blood flowing back into the left ventricle.

What are the causes of aortic valve insufficiency?

Any condition that prevents the leaflets of the aortic valve from closing properly causes aortic regurgitation. The most common cause of aortic insufficiency in developed countries is rheumatic aortic valve diseases. Recessions in the aortic valve leaflets caused by tonsil infections in childhood prevent the valve from closing completely. In addition, leaflet damage develops due to infective endocarditis (microbial infection in the valve) affecting the aortic valve and may cause aortic regurgitation. The aortic valve is the valve most affected by blunt chest trauma. Tearing and perforation of the aortic valve leaflets due to trauma can cause aortic regurgitation. Pathologies affecting the aortic tissue to which the valve is attached (connective tissue diseases such as Marfan, Ehler-danlos and osteogenesis imperfecta) may also cause insufficiency of the aortic valve. This includes aneurysms and dissections that cause enlargement of the aortic root. Aortic regurgitation may occur in patients with congenital bicuspid aortic valve. Aortic insufficiency may also develop in rheumatological diseases such as syphilis-related aortic involvement, rheumatoid arthritis and SLE, which are rare nowadays. What happens in aortic valve regurgitation? Volume overload occurs in the left ventricle of the heart due to the backward leakage of the aortic valve. If the process is slow, the left ventricle tries to tolerate this chronic volume overload by relaxing and expanding its volume. Thanks to the expansion and relaxation in the left ventricle, it is tried to prevent the accumulation of blood in the tissues behind the heart (left atrium and lungs) and the patient does not have any complaints. The size of the heart continues to grow insidiously. After a while, the contractile functions of the heart begin to deteriorate and the patient enters the picture of heart failure. In sudden onset of aortic regurgitation (such as infective endocarditis and acute aortic dissection extending to the valve), the patient soon enters the picture of pulmonary edema and cardiogenic shock, as the heart does not have enough time to adapt itself to this situation. What complaints are seen in aortic valve insufficiency? Mild aortic regurgitation does not cause any complaints in the patient. Since moderate and severe aortic regurgitation also has an insidious course, it does not cause any complaints in the patient for many years. Usually, the first complaint is shortness of breath with exertion, which indicates that the contraction force of the left ventricle has decreased. Patients also develop complaints of waking up at night with shortness of breath, being disturbed by the jolt of their heartbeat when they lie on their left side, and chest pain. Severe heart failure takes many years to develop.

Is aortic valve regurgitation fatal?

Half of the patients die within 10 years of aortic valve regurgitation. In patients who develop heart failure, 20 out of 100 patients die each year.

MITRAL VALVE DISEASES Where is the mitral valve located, what is its function and how does it work?

The blood, which is oxygenated in the lungs and comes to the left atrium of the heart through the pulmonary veins, passes between the opened mitral valve leaflets and fills the left ventricle to be pumped throughout the body. The left ventricle is the cavity with the strongest muscle tissue of our heart. Thanks to the high pressure created by the contraction of the left ventricle, it is possible to send the blood to the farthest points of our body. With the effect of this high pressure, the aortic valve leaflets are opened and the blood is pumped into the aorta (forward), while it does not allow it to escape to the left atrium (backwards) thanks to the closed mitral valve leaflets. The mitral valve has two leaflets. These leaflets are attached to a ring-like structure at their base. The free edges of the leaflets are attached to the muscle structures (papillary muscles) in the left ventricle with rope-like structures (chordae tendineae). Thanks to this structure of the valve, it is ensured that the free edges of the leaflets do not leak back blood despite the high left ventricular pressure. This structure is similar to the gliding of a person (papillary muscles) attached to the parachute (mitral valve leaflets) by threads (chordae tendineae). The pressure of the air (blood in the left ventricle) allows the parachute to open (close the mitral valve leaflets). The attachment of the mitral valve to the muscles in the left ventricle with rope-like structures prevents the valve from turning upside down with the effect of pressure.

MITRAL SQUARE

All pathologies that prevent the mitral valve leaflets from opening freely during the passage of blood from the left atrium to the left ventricle cause stenosis in the mitral valve. The main problem in mitral stenosis is that the valve cannot be opened sufficiently due to the leaflets sticking together, and therefore the passage of blood from the left atrium to the left ventricle becomes difficult. The left atrium starts to contract more strongly and expands in order to send the blood to the left ventricle due to the narrowing valve, but after a while, hardening develops in the pulmonary veins that bring the blood to the left atrium. Due to the hardening of the lung tissue, the pressure in the pulmonary artery rises and over time, the right ventricle begins to have difficulty pumping blood to the lungs. After a while, tricuspid valve insufficiency develops, and the right side of the heart also goes into insufficiency. An important problem in mitral stenosis is the frequent occurrence of arrhythmia called atrial fibrillation. If we compare normal sinus rhythm to a smooth wave created by a drop of water falling into a still lake, atrial fibrillation is like rain falling into a lake. Due to the chaotic rhythm that occurs, the contraction of the atria of the heart is disrupted. Clots form due to stagnation of blood in the left atrium. If these clots escape to the arteries of the arms and legs, they may cause gangrene, if they escape to the brain, they may cause paralysis, if they escape to the kidney arteries, kidney failure, and if they escape to the arteries that feed the intestines, necrosis in the intestines. All of these clinical pictures are life threatening. Normal mitral valve area (MCA) in adults is in the range of 4.0-5.0 cm2. Mild mitral stenosis: MCA ranges from 1.4-2.5 cm2. Complaints begin. The first complaints are shortness of breath, weakness and fatigue during heavy exercise. Moderate mitral stenosis: MCA is between 1.0-1.4 cm2. Shortness of breath during exercise or when lying on the back, waking up at night with shortness of breath begins. In some patients, pulmonary edema may develop suddenly after exercise (patient feels as if all airways are filled with water, cannot breathe. It is a life-threatening emergency). Severe mitral stenosis: MCA below 1.0 cm2. Even at rest, shortness of breath, indolence, and dependence on bed develop. If pulmonary hypertension secondary to mitral stenosis develops, the progression to right heart failure (edema in the legs, enlargement of the liver and fluid collection in the abdomen) begins. What are the causes of mitral stenosis, what is the course of mitral stenosis? The most common cause of mitral stenosis is acute rheumatic fever in childhood. Mitral stenosis occurs years after the first attack of rheumatic fever. Most of the patients have their first attack of acute rheumatic fever around the age of 12. In these patients, clinical signs of mitral stenosis begin to be detected around the age of 20. Complaints related to mitral stenosis occur in patients in their 30s. Mitral stenosis patients progress to end-stage heart failure (NYHA class-IV functional capacity) within 7-10 years from the first appearance of complaints. If no intervention is made for mitral stenosis, these patients die at the age of 40-50 on average. MITRAL INSUFFICIENCY What does it mean to have mitral valve regurgitation and what happens if there is mitral regurgitation? Causes such as a disconnection in the threads (chordae tendinea) that fix the free ends of the mitral valve to the papillary muscles in the left ventricle, dysfunction or rupture of the papillary muscles, tear or hole formation in the valve leaflets cause insufficiency in the mitral valve. * In case of advanced enlargement of the ring-like structure (annulus) to which the mitral valve leaflets are attached, the free edges of the two leaflets cannot make a solid contact with each other during closure and mitral valve insufficiency develops. The main problem in mitral regurgitation is that both the left atrium and the left ventricle have to cope with this high amount of blood due to blood escaping from the left ventricle. *Mitral regurgitation can be divided into acute mitral regurgitation and chronic mitral regurgitation according to the development time of the pathology: i. Chronic mitral insufficiency Since the process is very slow in chronic mitral regurgitation, the left ventricle begins to increase its internal volume gradually to adapt to this situation. Due to this adaptation, patients do not have any complaints for many years. However, after a while, the left ventricle, which grows insidiously, cannot contract well enough anymore and the patient develops complaints. The degree of mitral regurgitation is defined as mild, moderate or advanced according to the amount of blood flowing back. Usually, the first complaints are shortness of breath with exertion. Rhythm problems (atrial fibrillation) can also be seen in chronic mitral regurgitation. As in mitral stenosis, the clinical course progresses as high blood pressure in the pulmonary artery, enlargement in the right ventricle and tricuspid valve insufficiency, but unlike mitral stenosis, enlargement and failure in the left ventricle of the heart also occur in chronic mitral insufficiency. Mitral valve collapse (mitral valve prolapse) is the collapse of the valve towards the left ventricle during closure. It does not always lead to mitral regurgitation. This condition is quite common (found in 1-2.5% of the population). ii. Acute mitral regurgitation, unlike chronic mitral regurgitation, is a sudden onset condition. The heart does not have enough time to adapt itself. Due to the sudden insufficiency of the mitral valve, complaints and symptoms occur due to the rapid increase in blood pressure in the veins (pulmonary veins) that bring clean blood from the lungs. The painting is dramatic. Causes of acute mitral regurgitation: a. A rupture in the thread-like structures (chordae tendinea) holding the mitral leaflets, b. A microbial infection causing perforation or tearing of the leaflets (infective endocarditis), c. Dysfunction or rupture of the muscles (papillary muscles) to which the valve is attached by threads due to an acute heart attack.

TRICUSPIT VALVE DISEASES

Located between the right atrium and right ventricle of the heart, the tricuspid valve consists of three leaflets. They are similar to the mitral valve in terms of structure and operation. Problems in the tricuspid valve can be congenital or acquired (acquired). The most common cause of acquired tricuspid valve problems is that valve problems on the left side of the heart cause enlargement of the right ventricle over the years and as a result, an opening remains between the leaflets of the valve during closure due to the enlargement of the ring-like ring to which the tricuspid valve is attached. In this case of functional insufficiency, the most common surgical method is to re-narrow the valve ring by attaching a prosthetic ring. Tricuspid regurgitation also develops in 10-50% of patients with mitral valve problems. Insufficiency of the tricuspid valve due to microbial infection is common, especially in substance abusers. Tricuspid valve insufficiency may develop due to blunt traumas.