Aortic Valve Diseases

Aortic Valve Diseases and Aneurysm Surgery

What Is Aortic Stenosis?

Aortic stenosis can occur in 3 locations: below the valve, at the level of the valve, and above the valve. In adults, it is largely related to the valve. Valve-related aortic stenosis is divided into two types: rheumatic and non-rheumatic.

What Is Rheumatic Aortic Stenosis?

Rheumatic aortic stenosis accounts for 30-40% of patients in Western countries, while this rate is higher in our country. Due to rheumatism, the aortic valve shows thickening and inflammation, and over time the valve is damaged: the three normally mobile leaflets stick to each other and calcification (calcium deposition) develops, making the valve resemble a piece of stone. Rheumatic aortic stenosis frequently affects the mitral heart valve as well, although its clinical significance may vary.

What Is Non-Rheumatic Aortic Stenosis?

Non-rheumatic aortic stenosis takes two forms: 'Congenital' and 'Degenerative'. Congenital aortic stenosis is more common. Bicuspid aortic stenosis is the most frequently seen type. Normally the aortic valve has 3 leaflets, but in these cases the aortic valve has 2 leaflets. In 1 or 2 out of every 100 people in the population, the aortic valve is born bicuspid. These bicuspid valves may deteriorate over time or may follow a completely normal course. With deterioration of this valve, aortic stenosis, aortic regurgitation (leakage), or both (stenosis and leakage) may develop. Sometimes an infection of the heart valve, which we call endocarditis, may develop on this valve. Calcification of a congenital bicuspid valve results in calcific aortic stenosis. As calcification progresses, significant aortic stenosis usually develops in the 50s and 60s. Degenerative aortic stenosis is also named atherosclerotic, idiopathic calcific, or senile aortic stenosis. The valve has three normal leaflets. Calcification develops secondary to atherosclerosis (arterial hardening). Significant aortic stenosis develops in the 60s, 70s, and 80s.

Conditions Causing Aortic Stenosis?

Normally the aortic valve area is 2.5-3.5 m2. In aortic stenosis, when this area falls below 1 cm2, the patient's complaints begin. Below 0.7 cm2 is critical and serious. With aortic stenosis, the heart enlarges.

What Are the Symptoms of Aortic Stenosis?

Heart rhythm disturbances, chest pain, sudden fainting, and dimming of vision occur. As the disease progresses, sudden death may occur. Definitive diagnosis and the degree of valve narrowing are determined by echocardiography. Catheterization and angiography should be performed in patients with angina and in those over 40 years of age.

How Is Aortic Stenosis Treated?

1. In patients with symptoms (signs of heart failure, chest pain, fainting)
2. In patients without symptoms but with severe aortic stenosis on echocardiography (valve area below 0.7 cm2, gradient above 50 mmHg, and patients in whom the left ventricle has enlarged and its functions have begun to decline)

Especially in young children with bicuspid aortic stenosis, the valve is repaired and preserved whenever possible. In cases where the aortic valve area is very narrow, the Ross/Konne Procedure is performed: the patient's other valve (the pulmonary valve) is removed, enlarged, and implanted in place of the aortic valve.

What Is Aortic Regurgitation?

The heart enlarges depending on the degree of aortic regurgitation. It is one of the heart diseases that enlarges the heart the most. Its most common cause is acute rheumatic fever (acute joint rheumatism). Rheumatic fever causes fibrous thickening of the aortic valve and later retraction of the valve, producing aortic regurgitation. The second most common cause is infective endocarditis (on a bicuspid or normal valve). Infective endocarditis is a microbial infection of the heart valve. Also, in cases where a congenital hole between the two ventricles (VSD: Ventricular Septal Defect) is adjacent to or near the aortic valve, aortic regurgitation may develop over time. In chest trauma (traffic accident, fall, etc.), tearing of any leaflet of the aortic valve may cause aortic regurgitation. Other causes of aortic regurgitation include myxomatous degeneration, rheumatoid arthritis, and systemic lupus erythematosus. In Marfan Syndrome, which causes dilation of the aorta (and in arteriosclerotic or syphilitic aortic aneurysm through a similar mechanism), and in annuloaortic ectasia, where dilation occurs due to weakness of the aortic valve ring, aortic regurgitation develops whether or not Marfan Syndrome is present. Aortic dissection, in which a tear occurs between the layers of the aortic wall, may also cause aortic regurgitation. Various rheumatic and systemic diseases (Rheumatoid Arthritis, Reiter Syndrome, Psoriasis, Takayasu Disease) can involve the aortic valve and cause aortic regurgitation.

What Are the Symptoms of Aortic Regurgitation?

Initial findings are easy fatigue and shortness of breath; over time, shortness of breath at night that wakes the patient from sleep occurs. In a more advanced stage, chest pain and fainting spells may occur. The risk of sudden death increases when the heart is greatly enlarged. Definitive diagnosis and the degree of valve insufficiency are determined by echocardiography. Catheterization and angiography should be performed in patients with chest pain or those over 40 years of age.

How Is Aortic Regurgitation Treated?

1. Patients with symptoms (NYHA: New York Heart Association class III and IV) should be operated on. Impairment of the heart's contractile ability does not prevent surgery, but it increases the risk.
2. In patients without symptoms, when heart function (left ventricular function) begins to decline, or when the heart enlarges beyond critical levels (left ventricular diastolic diameter exceeding 7.5 cm, or systolic diameter exceeding 5.5 cm)
3. Also, in cases of acute (sudden) aortic regurgitation, emergency surgery should be performed.

In the surgical treatment of aortic valve diseases, especially in young children with bicuspid aortic valves, preserving the valve by repair is advantageous if the valve structure is suitable.

Also, in cases where the quality of the aortic valve is good but aortic regurgitation is due to enlargement of the aortic valve ring, the aortic valve can be preserved (David operation) and placed inside a synthetic graft, which treats the aortic regurgitation. When valve repair is not possible and life expectancy is long and there is no obstacle to using blood thinners, a mechanical heart valve should be implanted. If there is a risk that prevents the use of blood thinners (risk of brain hemorrhage, risk of bleeding in other organs) (over age 80), biological heart valves, meaning valves obtained from animals, are used. If the aortic ring is very small during surgery, it should be enlarged with dilating procedures so that a sufficiently large valve can be implanted. If the aortic ring is too narrow to be enlarged sufficiently by dilation (as in young children), the patient's own other valve, the pulmonary valve, is removed and placed in the aorta. This operation is called the Ross operation. It is a long, difficult operation that requires experience. The surgeon performing it must have experience with this operation.

What Is Idiopathic Hypertrophic Subaortic Stenosis?

Hypertrophic subaortic stenosis is a special form of hypertrophic cardiomyopathy (a disease in which the heart muscles are greatly enlarged). In hypertrophic subaortic stenosis, there is an abnormal muscle structure, beyond the normal, that narrows the outflow of the left ventricle, and its clinical picture resembles aortic stenosis. Hypertrophic subaortic stenosis is a familial, hereditary disease of unknown cause.

What Are the Symptoms of Idiopathic Hypertrophic Subaortic Stenosis?

Complaints usually appear in the 20s and 30s. The complaints are usually shortness of breath, chest pain, and sudden fainting. The exact cause of sudden fainting is not fully known, but it is thought to be related to a heart rhythm disturbance. The risk of sudden death is high in cases of hypertrophic subaortic stenosis. Definitive diagnosis is made by echocardiography, and treatment is planned.

How Is Idiopathic Hypertrophic Subaortic Stenosis Treated?

Patients with symptoms are treated with beta-blockers and calcium channel blockers.

1. In patients who do not respond to drug therapy and have many complaints (the group with New York Heart Association class 3 and 4)
2. Surgery is required in patients who have sudden fainting attacks and severe narrowing.

In treatment, the muscle structures causing the narrowing are cut away and removed. Another treatment method is the placement of a mitral valve.

What Are Mitral Valve Diseases?

The mitral valve area is 5-11.4 cm2 (average 7.6 cm2). The mitral valve is a valve structure made up of two leaflets, located adjacent to the left ventricle. The most common cause of mitral valve disease in our country and in developing countries is rheumatic heart disease, whereas in Western society, mitral valve disease caused by rheumatism has markedly decreased. In Western society, degenerative and distrophic lesions and mitral regurgitation are commonly seen in advanced age.

What Is Mitral Stenosis?

Apart from the rarely seen congenital mitral stenosis, it is almost always related to acute rheumatic fever. Rheumatic mitral valve disease can lead to stenosis, regurgitation, or both. Acute rheumatic fever in early childhood mostly causes mitral regurgitation, while in young adults mitral stenosis develops, and at older ages both together (mitral stenosis and regurgitation) develop. In rheumatic mitral stenosis, as the disease progresses over time, a clot (thrombus) may form inside the left atrium. Clots breaking off from here may travel to the brain and cause a stroke, or cause blockages in other vessels. Apart from rheumatism, mitral stenosis may very rarely occur due to late-age calcification of the valve structure (calcification), in some malignant cancers (carcinoid syndromes), in large clots and tumors inside the left ventricle, and in small or narrowed implanted mitral prostheses.

What Are the Symptoms of Mitral Stenosis?

Shortness of breath, easy fatigue, shortness of breath at night that wakes the patient from sleep, palpitations, and bloody sputum are the most common findings. Complaints usually do not appear until the valve area is 2-2.5 cm2. Definitive diagnosis is made by echocardiography, and treatment is planned.

How Is Mitral Stenosis Treated?

• Indications for open-heart surgery for mitral stenosis
• Fatigue limiting daily activity (NYHA: New York Heart Association class III and IV)
• Systemic embolism
• Presence of a clot inside the left atrium
• To preserve the existing mitral valve (to avoid valve replacement) in people who have severe narrowing but fewer complaints
• Recommended for women without symptoms who wish to become pregnant.

In surgical treatment, efforts should first be made to preserve the existing mitral valve. If the valve is not severely calcified, the narrowing of the existing valve is relieved and the thickened valve structure is thinned. If severe calcification is present, a prosthetic valve is implanted.

What Is Mitral Regurgitation?

In our country and in developing countries, its most common cause is related to rheumatism. The valve most commonly affected by rheumatism is the mitral valve. In Western society, the most common cause is degenerative and distrophic lesions.

What Is Ischemic Mitral Regurgitation?

Mitral regurgitation may occur due to blockage of the coronary arteries that supply the heart. It is seen especially after repeated heart attacks (myocardial infarction), together with impaired contractile ability and enlargement of the heart. Also, tearing or rupture of the structures that hold the valve after a heart attack may cause mitral regurgitation.

Myxomatous Degeneration (Mitral Valve Prolapse, Floppy Mitral Valve, Myxomatous Mitral Valve, Degenerative Mitral Valve)
Mitral regurgitation frequently affects the valve structures in elderly individuals. Initially these structures elongate, and then, as they rupture, mitral regurgitation worsens. Myxomatous or degenerative valve disease (floppy mitral valve or mitral valve prolapse) is one of the most important causes of mitral regurgitation in Western society.

What Is Endocarditis?

It is a microbial infection of the mitral valve. It is a serious and severe disease. With appropriate antibiotic treatment, it frequently requires surgical intervention. In bacterial endocarditis, mitral valve repair is more advantageous.

What Is Mitral Annular Calcification?

This disease is essentially a degenerative disease seen in the elderly. It is frequently seen in women over 60. Its etiology is not fully known. Among systemic diseases, Ehlers-Danlos and Marfan Syndrome can cause mitral regurgitation by causing expansion of the valve ring and elongation of the structures beneath the valve. Other systemic diseases include amyloidosis, sarcoidosis, polyarthritis, and hypereosinophilia.

What Are the Symptoms of Mitral Annular Calcification?

Complaints such as easy fatigue, palpitations, weakness, and tiredness are present. Definitive diagnosis is made by echocardiography, and treatment is planned.

How Is Mitral Annular Calcification Treated?

In patients with grade 3 and 4 mitral regurgitation, surgery should be performed while cardiac functions are still preserved.

• Fatigue limiting daily activity (NYHA: New York Heart Association class III and IV)
• Patients with fewer complaints but an enlarged heart (left ventricular systolic diameter above 5.5 cm and diastolic diameter above 6 cm)
• If severe mitral regurgitation develops after a heart attack (myocardial infarction)
• May be required in endocarditis, a microbial disease of the mitral valve.

In surgical intervention, it should first be evaluated whether the existing mitral valve can be repaired.

How Are Patients with Multiple Valve Diseases Treated?

In some patients, the mitral and aortic valves, and even the tricuspid valve, may be diseased. In these cases, all three valves are addressed depending on the severity of the valve disease. Rheumatic heart disease is still the most common cause of multiple valve disease in our country. Apart from this, endocarditis (infection of the heart valves) and the other causes mentioned for single valve diseases may also cause multiple valve diseases. In three-valve disease, the mitral and aortic valves are usually replaced, while the tricuspid valve is repaired.