Thrombotic endocarditis and lupus anticoagulant. A pathogenetic possibility for idiopathic 'rheumatic type' valvular heart disease.

Lupus anticoagulant and anti-phospholipid antibodies are well recognized as being associated with thromboembolic disorders in patients both with and without systemic lupus erythematosus (SLE). There have been recent reports of the association of lupus anticoagulant and antiphospholipid antibodies with severe valvular heart disease in patients with SLE and it has been suggested that organizing thrombus on the surface of the valve may be a cause of distortion and subsequent dysfunction. We describe two patients who did not have SLE, but who did have both lupus anticoagulant and antiphospholipid antibodies. Both had severe valvular heart disease, the pathology of which demonstrates valve distortion by layers of organizing thrombus identical to that of previously described patients with SLE. The gross appearance of these valves is similar to that of the valves in "rheumatic" heart disease. We suggest that in some patients with "rheumatic" heart disease, but without a history of rheumatic fever, the prothrombotic tendency associated with lupus anticoagulant and phospholipid antibodies may either contribute to, or be responsible for, the pathogenesis of "rheumatic" type valve deformities.