Tricuspid regurgitation - valve disease

Tricuspid regurgitation

Definition

Retrograde blood flow from the right ventricle to the right atrium during systole.

Aetiology

Tricuspid regurgitation can be divided into functional, i.e. secondary to dilation of the right ventricle, and or-ganic tricuspid regurgitation:

Functional tricuspid regurgitation occurs with cor pulmonale, right-sided myocardial infarction or pulmonary hypertension.

Organic tricuspid regurgitation occurs with rheumatic mitral valve disease, infective endocarditis and the carcinoid syndrome. Infective endocarditis affecting the tricuspid valve is seen particularly in intravenous drug abusers. Ebstein’s anomaly is a congenital dysplasia of the tricuspid valve with abnormal valve cusps and a downward malpositioning of the valve.

Pathophysiology

Regurgitation of blood into the right atrium during systole results in high right atrial pressures and hence right atrial hypertrophy and dilatation. Volume overload results in an initial increase in right ventricular stroke volume (Starling’s mechanism) until decompensation occurs, after which there is a reduction in cardiac output and signs of right-sided heart failure.

Clinical features

Patients may present with symptoms and signs of right-sided heart failure such as ankle oedema, fatigue and ascites. On examination a prominent V (systolic) wave may be seen in the JVP  and a pulsatile enlarged liver may be palpable. A right ventricular heave may be felt at the left sternal edge. On auscultation there is a pansystolic murmur, which unlike mitral regurgitation is accentuated by inspiration heard best at the left lower sternal edge.

Complications

Atrial fibrillation is very common. In the chronic un-treated patient there can be hepatic cirrhosis from the pressure effect on the liver.

Investigations

The chest X-ray may show right atrial and ventricular enlargement. Echocardiography is diagnostic and is also essential to assess right ventricular function.

Management

Functional tricuspid regurgitation usually resolves with management of heart failure. Severe organic tricuspid regurgitation or refractory functional regurgitation may require operative repair (or rarely replacement).