Libman-Sacks endocarditis

Libmann-Sacks endocarditis (LSE) or , also known as verrucous endocarditis, is a form of Nonbacterialnonbacterial thrombotic endocarditis or sterile endocarditis characterised characterised by large thrombi vegetations over the endocardial surface. It was considered the predominant form of endocarditis in Systemicsystemic lupus erythematosus (SLE) until treatment with corticosteroids was introduced.

Epidemiology

Data for Libman-Sacks endocarditis comes from several case controlled studies and cohort studies of patients with SLE. The prevalence of LSE in one prospective cohort study was estimated by trans thoracic echocardiogramstransthoracic echocardiogram at around 11%.¹ However. However, on post-mortem findings in older studies performed between 1950-1960 identified rates were as high as 35-65% of patients with SLE.².

Pathophysiology

SLE is characterised by the presence of autoantibodies such as antiphospholipid antibodies. Studies have found that there is selective deposition of complement and immune complexes along the endocardial surface leading to aggregation of platelets along the endocardial wall.³ The exact mechanism by which antiphospholipid antibodies are involved in the pathogenesis remains unclear. 

Clinical Features

Most patients are asymptomatic as the lesions do not form near the closing line of the valves and hence valvular function is often not affected until later on during the course of the disease. Regurgitant lesions arevalvular disease is more common than stenotic lesionsdisease.

Since these patients are at an increased risk of forming thrombi, patients may also present with acute myocardial infarctions and or ischaemic strokes³.⁴ These These patients are also more prone to bacterial endocarditis and several case reports have been doccumenteddocumented in literature citing diagnostic dilemmas⁴.

Pathology

SLE is characterised by the presence of autoantibodies, such as antiphospholipid antibodies. It has been postulated that there is selective deposition of complement and immune complexes along the endocardial surface leading to aggregation of platelets along the endocardial wall ⁵. The exact mechanism by which antiphospholipid antibodies are involved in the pathogenesis remains unclear. 

Role of ImagingEchocardiography

Thransthoracic echocardiogram (TTE) had been considered the best initial test for the evaluation of LSE. RecentHowever, recent studies have identified that Transtrans-oesophageal echocardiogramsechocardiogram (TOE) hadmay have a higher sensitivity, specificity, positive, and negative predictive valuesvalue compared to TTEs.TTE ⁶.

Further studies have demonstrated that three dimensional-dimensional echocardiography (3D-TEE) is better at characterising valvular lesions (aortic and mitral valve lesions)⁷. In these studies, 3D-TEE also detected more lesions in patients with cerebrovascular disease.⁷.

Currently, the role of 4D-flow MRI imaging as useful noninvasive tool for evaluating abnormal flow patterns, ventricular dimensions, stroke volume, and regional myocardial function, is being investigated. Some early studies have shown promising results as they have been able to more accurately demonstrate the above parameters compared to traditional TOE.⁸.

The management of LSE consists of managing the underlying disease process with appropriate immunosuppressant therapy. Patients may benefit from anticoagulation. However, the risks and contraindications of anticoagulation must be weighed. SurgerySurgery or additional pharmacotherapy may be indicated in acute valvular rupture or heart failure.

History and etymology

It was first described by Emanuel Libman (1872-1946) and Benjamin Sacks, American physicians, in their 1924 seminal paper ⁹.