Libman-Sacks endocarditis

Synonyms: verrucous endocarditis

What is Libman-Sacks endocarditis?¹

Libman-Sacks endocarditis (LSE) is a rare cardiac manifestation of systemic lupus erythematosus (SLE).

Libman-Sacks endocarditis causes sterilised vegetations that mostly affects the mitral valve and possibly the aortic valve. The left heart is much more commonly affected. It may present with symptoms of heart failure due to valvular regurgitation and thromboembolic events.

Libman-Sacks endocarditis is typically situated in the tip, middle, or the base of the posterior mitral leaflets and this can be confused with infective endocarditis vegetation.

Libman-Sacks endocarditis is often missed at echocardiography.

Although the condition is classically associated with SLE, it can also occur in antiphospholipid syndrome (APS).

How common is Libman-Sacks endocarditis? (Epidemiology)²

• With a prevalence of between 0.9% and 1.6%, Libman-Sacks endocarditis is an uncommon disease that is typically discovered postmortem.

• One study found that 61% of SLE patients who underwent transoesophageal echocardiography had valvular abnormalities.

• Pericarditis, myocarditis, Libman-Sacks endocarditis, pulmonary arterial hypertension, conduction dysfunction, and coronary artery disease are thought to be present in more than 50% of SLE patients.

History¹

• Most patients with Libman-Sacks endocarditis are asymptomatic.

• If valves are severely affected there may be features of the valve disease. Mitral valve disease is more common than aortic valve disease. Regurgitation is more frequent than stenosis and involvement of the tricuspid or pulmonary valves is unusual.

• Systemic embolism may occur with effects depending upon the destination of the emboli but brain and kidney are likely victims. Emboli can cause blockage of the peripheral circulation.

• The vegetations of Libman-Sacks endocarditis are sterile but secondary infective endocarditis can occur.

• There may or may not be typical features of SLE with the characteristic butterfly rash, fever and arthritis or features of APS, including recurrent miscarriage.

Examination

• Physical signs reflect the pathology and can be found in the various articles on mitral valve disease or aortic valve disease, infective endocarditis and, if the valve disease is severe, congestive heart failure.

• There may also be left ventricular hypertrophy, causing displacement of the apex beat.

Investigations¹

• Echocardiography: not all lesions will be detected. Results with transoesophageal echo are superior but it is an invasive procedure.

• Blood culture is important to exclude infective endocarditis (IE), which may coexist.

• Investigations for SLE, including antiphospholipid antibodies and other autoantibodies. False positive serology in the form of VDRL is common in SLE and anticardiolipin antibodies increase the risk of cardiac abnormalities.

• FBC may show raised neutrophils and some anaemia.

• CXR may show cardiomegaly and pulmonary congestion if disease is severe. Calcification of lesions is uncommon.

• If valvular disease seems severe then cardiac catheterisation may be required with a view to valve replacement.

Libman-Sacks endocarditis treatment and management²

• There is no specific treatment for Libman-Sacks endocarditis.

• Steroids and immunosuppressive agents are useful in the treatment of the underlying disease but there is some controversy about their role in the pathogenesis of vegetations.

• Advice for procedures creating risk of infective endocarditis can be found in the separate record Prevention of Endocarditis.

• If there are systemic emboli then anticoagulation is beneficial but the possible role of aspirin has not been adequately investigated.

• If there is evidence of one cerebrovascular event, anticoagulation is advised.³

• In serious valve disease it may be necessary to replace valves.

Complications²

• Systemic emboli may occur but they are probably not very common.

• The risk is much higher with mitral stenosis and subsequent atrial fibrillation.

• When strokes occur it is difficult to know if they were due to systemic emboli or the underlying pathology of SLE or APS.

• Valvular disease can lead to heart failure.

• Maternal SLE with anti-Ro/SS-A (Sjögren's syndrome antigen A) autoantibodies is associated with congenital heart block in the baby in about 1 or 2%. It is usually complete but can be 1st or 2nd degree. The rate of recurrence is around 16%. Fluorinated steroids that do not cross the placenta may be beneficial.⁴

Prognosis

The prognosis will depend on the extent and severity, as well as the other manifestations of SLE.