(See also Overview of Cardiac Valvular Disorders.)
Tricuspid stenosis (TS) is narrowing of the tricuspid orifice that obstructs blood flow from the right atrium to the right ventricle. Almost all cases result from rheumatic fever. Symptoms include a fluttering discomfort in the neck, fatigue, cold skin, and right upper quadrant abdominal discomfort. Jugular pulsations are prominent, and a presystolic murmur is often heard at the left sternal edge in the 4th intercostal space and is increased during inspiration. Diagnosis is by echocardiography. TS is usually benign, requiring no specific treatment, but symptomatic patients may benefit from surgery.
Rare causes of tricuspid stenosis include SLE, right atrial (RA) myxoma, congenital malformations, and metastatic tumors.
The RA becomes hypertrophied and distended, and sequelae of right heart disease–induced heart failure develop but without right ventricular (RV) dysfunction; the RV remains underfilled and small. Uncommonly, atrial fibrillation occurs.
The only symptoms of severe tricuspid stenosis are fluttering discomfort in the neck (due to giant a waves in the jugular pulse), fatigue and cold skin (due to low cardiac output), and right upper quadrant abdominal discomfort (due to an enlarged liver).
The primary visible sign is a giant flickering a wave with gradual y descent in the jugular veins. Jugular venous distention may occur, increasing with inspiration (Kussmaul sign). The face may become dusky and scalp veins may dilate when the patient is recumbent (suffusion sign). Hepatic congestion and peripheral edema may occur.
On auscultation, tricuspid stenosis is often inaudible but may produce a soft opening snap and a mid-diastolic rumble with presystolic accentuation. The murmur becomes louder and longer with maneuvers that increase venous return (exercise, inspiration, leg-raising, Müller maneuver) and softer and shorter with maneuvers that decrease venous return (standing, Valsalva maneuver).
Findings of tricuspid stenosis often coexist with those of mitral stenosis and are less prominent. The murmurs can be distinguished clinically (see Table: Distinguishing Murmurs of Tricuspid Stenosis and Mitral Stenosis).
Distinguishing Murmurs of Tricuspid Stenosis and Mitral Stenosis
Diagnosis is suspected based on history and physical examination and confirmed by Doppler echocardiography showing a pressure gradient across the tricuspid valve. Severe tricuspid stenosis is signified by a mean forward gradient across the valve > 5 mm Hg. Two-dimensional echocardiography shows thickened leaflets with reduced movement and RA enlargement.
ECG may show RA enlargement out of proportion to RV hypertrophy and tall, peaked P waves in inferior leads and V1.
Chest x-ray may show a dilated superior vena cava and RA enlargement, indicated by an enlarged right heart border.
Liver enzymes are elevated because of passive hepatic congestion.
Cardiac catheterization is rarely indicated for evaluation of tricuspid stenosis. When catheterization is indicated (eg, to evaluate coronary anatomy), findings include elevated RA pressure with a slow fall in early diastole and a diastolic pressure gradient across the tricuspid valve.
Evidence to guide treatment of tricuspid stenosis is scarce. Symptomatic patients not undergoing intervention should receive a low-salt diet, diuretics, and aldosterone antagonists.
Patients with severe tricuspid stenosis should undergo intervention if they are symptomatic or if cardiac surgery is being done for other reasons. Percutaneous balloon tricuspid commissurotomy might be considered for severe TS without accompanying tricuspid regurgitation.
Tricuspid stenosis is almost always due to rheumatic fever; tricuspid regurgitation and mitral stenosis are often also present.
Heart sounds include a soft opening snap and a mid-diastolic rumble with presystolic accentuation; the murmur becomes louder and longer with maneuvers that increase venous return (eg, exercise, inspiration, leg-raising) and softer and shorter with maneuvers that decrease venous return (standing, Valsalva maneuver).
Treatment includes diuretics and aldosterone antagonists; surgical repair or replacement is rarely needed.