Tricuspid Regurgitation – leakage of the tricuspid

Tricuspid Regurgitation – leakage of the tricuspid

Tricuspid Regurgitation – leakage of the tricuspid: Tricuspid valve is the largest of the four heart valves, which prevents backflow of blood from the right ventricle when it contracts, to the right atrium. Tricuspid regurgitation (leakage of tricuspid valve) is most often secondary to elevated right ventricular pressure as a consequence of pulmonary hypertension (increase in pressure in the blood vessel carrying deoxygenated blood to the lungs for oxygenation). Hence it is often associated with other valvular disorders like mitral stenosis which cause elevation of pulmonary pressures. In rheumatic heart disease, isolated tricuspid regurgitation will be very unlikely as the mitral valve will be invariably affected in such cases.

Tricuspid regurgitation can be divided into hypertensive and nonhypertensive (associated with high pressures in the pulmonary artery and those associated with normal pressures in the pulmonary artery). Non-hypertensive tricuspid regurgitation occurs due to structural abnormalities of the tricuspid valve like Ebstein’s anomaly (condition in which tricuspid valve is attached more towards the tip of the right ventricle than normally). Tricuspid valve endocarditis (infection of the tricuspid valve) is also an important cause of tricuspid regurgitation, especially in intravenous drug abusers (mainline drug users). Tricuspid regurgitation is also a feature of carcinoid heart disease (disease caused by serotonin secreting tumors which have spread to the liver). Severe tricuspid regurgitation produces right atrial dilatation (enlargement of the right upper chamber of the heart) and a prominent V wave in the jugular venous pulse (pulsations in the blood vessels draining deoxygenated blood from the head and neck). Severe tricuspid regurgitation produces pulsations of the liver with each cardiac contraction (prominent hepatic systolic pulsations). Severe tricuspid regurgitation may also be associated with ascites (fluid collection in the abdominal cavity) and edema (collection of fluid underneath the skin) of the legs, when the right ventricle fails. The liver is also enlarged in this case.

Severe tricuspid regurgitation requires surgical repair. de Vega’s annuloplasty (repair of the valve ring) is useful in controlling tricuspid regurgitation. In this procedure, de Vega’s annuloplasty ring is sewn at the annulus (natural ring of attachment of valve leaflets) to reduce its dimensions and thereby reducing the leak which occurs mostly because the valve leaflets do not touch each other when the enlarged right ventricle contracts. Rare cases may require prosthetic valve (artificial valve) replacement.

Bioprosthesis (sterilized animal valve sewn on to a metallic ring for support) is preferred in tricuspid location because of the tendency for thrombosis (clotting of blood) due to the low velocity of blood flow across the tricuspid valve. Unlike in the mitral and aortic position, degeneration of bioprosthesis is lesser in the tricuspid position due to lower hemodynamic load (pressure exerted by the blood in the right ventricle when it contracts).