Section 3. Heart and Blood Vessel Disorders

Chapter 28. Heart Valve Disorders

Topics: Introduction | Mitral Regurgitation | Mitral Valve Prolapse | Mitral Stenosis | Aortic Regurgitation | Aortic Stenosis | Tricuspid Regurgitation | Tricuspid Stenosis | Pulmonary Stenosis

Tricuspid Stenosis

Tricuspid stenosis is a narrowing of the tricuspid valve opening that increases resistance to blood flow from the right atrium to the right ventricle.

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. Tricuspid regurgitation rarely occurs.

Nearly all cases are caused by rheumatic fever, which has become rare in North America, Australasia, and Western Europe. Rarely, the cause is a tumor in the right atrium, a connective tissue disorder, or, even more rarely, a birth defect of the heart.

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 (see Section 3, Chapter 21) 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 (ECG) (see Section 3, Chapter 21) shows changes indicating that the right atrium is strained.

Tricuspid stenosis is rarely severe enough to require surgical repair.