Tricuspid Stenosis

(See also Overview of Heart Valve Disorders Overview of Heart Valve Disorders Heart valves regulate the flow of blood through the heart's four chambers—two small, round upper chambers (atria) and two larger, cone-shaped lower chambers (ventricles). Each ventricle has... read more and the video .)

The tricuspid valve is in the opening between the right atrium and the right ventricle. The tricuspid valve opens to allow blood from the right atrium to fill the right ventricle and closes to prevent blood from flowing backwards into the right atrium as the right ventricle contracts to pump blood into the lungs. If a disorder causes the valve flaps to become thick and stiff, the valve opening is narrowed (stenosis). Often, the stiffened valve also fails to close completely and tricuspid regurgitation Tricuspid Regurgitation Tricuspid regurgitation is leakage of blood backward through the tricuspid valve each time the right ventricle contracts. Tricuspid regurgitation is caused by disorders that enlarge the right... read more develops.

Over many years, the right atrium enlarges because blood flow through the narrowed valve opening is partially blocked, increasing the volume of blood in the atrium. In turn, this increased volume causes an increase in pressure in the veins bringing blood back to the heart from the body (except the lungs). However, the right ventricle shrinks, because the amount of blood entering it from the right atrium is reduced.

Nearly all cases are caused by rheumatic fever Rheumatic Fever Rheumatic fever is inflammation of the joints, heart, skin, and nervous system, resulting from a complication of untreated streptococcal infection of the throat. This condition is a reaction... read more . Rheumatic fever is a childhood illness that occurs after some cases of untreated strep throat Symptoms Streptococcal infections are caused by any one of several species of Streptococcus. These gram-positive, sphere-shaped (coccal) bacteria (see figure ) cause many disorders, including... read more or scarlet fever Symptoms Streptococcal infections are caused by any one of several species of Streptococcus. These gram-positive, sphere-shaped (coccal) bacteria (see figure ) cause many disorders, including... read more . Rheumatic fever is now rare in North America and Western Europe because antibiotics are widely used to treat these infections. Rarely, the cause is a tumor in the right atrium, a connective tissue disorder, or, even more rarely, a birth defect of the tricuspid valve.

Symptoms are usually mild. They include palpitations (awareness of heartbeats), a fluttering discomfort in the neck, cold skin, and fatigue. Abdominal discomfort may result if the increased pressure in the veins causes the liver to enlarge.