Aortic Valve

Anatomy

The normal aortic valve consists of three equally sized valve cusps, namely the right coronary cusp (R), the left coronary cusp (L) and the non-coronary cusp (N).

With 2D echocardiography, the valve can be assessed in the Plax, where one sees the RCC and the NCC. In a normal aortic tricuspid valve closure line is then between the RCC and NCC is usually in the center of the aortic valve ring. One sees better the aortic valve in the PSAXao however, where the three cusps in systole almost form a circle and diastole in an inverted Mercedes-Benz logo. Assessing the number of cusps is done in systole, because the valve is open and because in the closed position can be seen as a raphe purse line. With 3D echocardiography you can now get wonderful images of the aortic valve.

3D (TEE) view of the aortic valve to exclude vegetations.

Aortic valve variants (PLAX ao)

Tricuspid (normal)	Bicuspid
Quadricuspide	Unicuspide

Bicuspid aortic valve

Bicuspid aortic valve is the most common cardiac valve abnormality. Here are two leaflets fused at the development. A bicuspid aortic valve occurs in 1-2% of the population and twice as often in men as in women.

A bicuspid aortic valve can be hereditary, both familial clustering and isolated valve defects are documented. The incidence of bicuspid aortic valve may reach 10% in certain families. A bicuspid aortic valve is often associated with other congenital heart defects, including coarctation of the aorta. Usually there is a fusion between the LCC and RCC (70%). In many cases, the bicuspid aortic valve do not cause any problems. Later in life, the valve will calcify early causing a stenosis occurs and possibly leak through malcoaptatie of the affected cusps.

Stenosis

Causes
Supravalvulair: (usually congenital)	A pleat or membrane of the aorta Narrowing of the aorta William's Syndrome
Valvular:	Congenital form; often than bicuspid aortic valve Due to rheumatic fever Degenerative form
Subvalvular:	Congenital anomaly: a membrane in LVOT Hypertrophic obstructive cardiomyopathy, an autosomal dominant hereditary disorder Aortic subvalvular stenosis has also been described as a result of any of the lysosomal storage diseases

Some patients have no symptoms, sudden, unexpected death, the first phenomenon. Fatigue, shortness of breath and lack of oxygen during exertion, chest pain and dizziness and fainting during exercise are further symptoms. The left ventricle must be at a higher pressure aortic valve stenosis in order to generate gain. Blood in the aorta rises in the long run by left ventricular pressure load. Depending on the severity and cause of the problem, a valve replacement may be indicated.

Click here for quantification of aortic valve stenosis.

Insufficiency

Causes
Congenital	Bicuspid aortic valve
Risk of damage to the aortic valve	Rheumatic fever Degeneracy Endocarditis Syphilis Trauma Metabolic diseases, such as the mucopolysaccharidosen
Aortic dilation	Connective tissue disease, such as Marfan's syndrome, Ehlers-Danlos syndrome, Aneurysm by inflammation, such as syphilis, vasculitis. Aneurysm atherosclerotic lesions in aorta Aortic dissection

A serious aortic regurgitation causes a volume overload of the left ventricle. Since the blood that has been pumped out, must be pumped back in touches the left ventricular causing overload and heart failure occurs. Patients complain of fatigue and shortness of breath. The valve, and possibly a part of the aortic arch, can be replaced.

Click here for quantification of aortic valve insufficiency.