(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 .)
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 How Bacteria Shape Up) cause many disorders... 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 How Bacteria Shape Up) cause many disorders... 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.
Through a stethoscope, doctors may hear the characteristic murmur of tricuspid stenosis. A chest x-ray shows that the right atrium is enlarged.
Echocardiography Echocardiography and Other Ultrasound Procedures Ultrasonography uses high-frequency (ultrasound) waves bounced off internal structures to produce a moving image. It uses no x-rays. Ultrasonography of the heart (echocardiography) is one of... read more can produce an image of the narrowed valve opening and show the amount of blood passing through the valve, so that the severity of the stenosis can be determined. Electrocardiography Electrocardiography Electrocardiography (ECG) is a quick, simple, painless procedure in which the heart’s electrical impulses are amplified and recorded. This record, the electrocardiogram (also known as an ECG)... read more (ECG) shows changes indicating that the right atrium is strained.
People are encouraged to eat a low-salt diet and are given diuretics and drugs to block the effects of aldosterone (which help decrease pressure in the veins).
Surgical repair is usually avoided because tricuspid stenosis is rarely severe enough to require it and stenosis often recurs after the repair.
The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
American Heart Association: Heart Valve Disease: Provides comprehensive information on diagnosis and treatment of diseases of the heart valves