Heart Valve Involvement (Libman-Sacks Endocarditis) in the Antiphospholipid Syndrome

Abstract

The antiphospholipid syndrome (APS) is defined by the presence of anti-phospholipid antibodies (aPLs) and venous or arterial thrombosis, recurrent pregnancy loss, or thrombocytopenia. The syndrome can be either primary or secondary to an underlying condition, most commonly systemic lupus erythematosus (SLE). Echocardiographic studies have disclosed heart valve abnormalities in about a third of patients with primary APS. SLE patients with aPLs have a higher prevalence of valvular involvement than those without these antibodies. Valvular lesions associated with aPLs occur as valve masses (nonbacterial vegetations) or thickening. These two morphological alterations can be combined and are thought to reflect the same pathological process. Both can be associated with valve dysfunction, although such association is much more common with the latter alteration. The predominant functional abnormality is regurgitation; stenosis is rare. The mitral valve is mainly affected, followed by the aortic valve. Valvular involvement usually does not cause clinical valvular disease. The presence of aPLs seems to further increase the risk for thromboembolic complications, mainly cerebrovascular, posed by valve lesions. Superadded bacterial endocarditis is rare but may be difficult to distinguish from pseudoinfective endocarditis. The current therapeutic guidelines are those for APS in general. Secondary antithrombotic prevention with long-term, high-intensity oral anticoagulation is advised. The efficacy of aspirin, either alone or in combination, is yet to be assessed. Corticosteroids are not beneficial and may even facilitate valve damage. Immunosuppressive agents should only be used for the treatment of an underlying condition. Current data suggest a role for aPLs in the pathogenesis of valvular lesions. aPLs may promote the formation of valve thrombi. These antibodies may also act by another mechanism, as indicated by the finding of subendothelial deposits of immunoglobulins, including anticardiolipin antibodies, and of colocalized complement components in deformed valves from patients with APS.

Antiphospholipid syndrome associated with non-infective mitral valve endocarditis: a case report

“…Th e presence of antiphospholipid antibodies increases the future risk for cerebrovascular complications such as stroke caused by an embolus from an aff ected valve. In the treatment of valvular lesions the most important thing is to establish an adequate anticoagulation using oral anticoagulant therapy along with corticosteroids and immunosuppressive agents (4). Antiphospholipid syndrome may be the cause of recurrent myocardial infarction.…”

Establishing the Diagnosis of Libman–Sacks Endocarditis in Systemic Lupus Erythematosus

“…1 Libman-Sacks valvular lesions are sterile fibrofibrinous vegetations that favor the left-sided heart valves and usually form on the ventricular surface of the mitral valve. 2 The disease progresses from a variable extent of inflammation along with fibrin deposits acutely to end stage or healed forms with a fibrous plaque. The pathogenesis is thought to involve the formation of fibrin-platelet thrombi, which organizes and leads to fibrosis and scarring with subsequent valve dysfunction.…”

“…the white blood cell count, 2. the CRP level, 3. the antiphospholipid antibody (aPL) level. 2 The white blood cell count in SLE would be expected to be low during a lupus flare. The CRP would be expected to be quite elevated in infection and possibly suppressed in lupus.…”

Cardiac Valve Diseases and Antiphospholipid Syndrome

“…There are many reports regarding this issue, some of them were cited by Morita et al (3). Those data suggest that the presence of aPLs represents a risk for having valvular involvement in patients with SLE and/or APS (8). The pathogenesis of Libman-Sacks endocarditis has been hypothesized to involve fibrin thrombi on the altered valve and its organization leads to fibrosis and dysfunction (9).…”

“…The pathogenesis of Libman-Sacks endocarditis has been hypothesized to involve fibrin thrombi on the altered valve and its organization leads to fibrosis and dysfunction (9). aPLs may play a role to mediate valvular damage by promoting thrombin formation on the endothelium (8). A number of studies have shownthe interaction of aPLs on the endothelial cell activation, leading to the procoagulant state (10)(11)(12).…”