Mitral Valve Replacement for Enlarged Libman-Sacks Endocarditis in a Patient with Persistent Primary Antiphospholipid Syndrome and Recurrent Stroke: A Case Report

Abstract

BACKGROUND Anticardiolipin antibodies in patients with Libman-Sacks endocarditis (LS) are indicative of comorbid antiphospholipid syndrome (APS) and can result in cerebral infarctions. We describe a case of LS and primary APS with recurrent cerebral infarctions despite anticoagulation treatment. The patient underwent surgery for enlarged LS vegetation with high titers of antiphospholipid antibodies. CASE REPORT A 41-year-old Japanese man was admitted to hospital for small cerebral infarction recurrence in a left parietal lesion. At age 35, the patient had suffered multiple cerebral infarctions. He was found to have high serum titers of all 3 antiphospholipid antibodies. Transesophageal echocardiography (TEE) findings were normal. Differential diagnosis ruled out other autoimmune diseases and a clinical diagnosis of primary APS was made. Warfarin anticoagulation was started. When cerebral infarction recurred 6 years after the first episode, serum titers of antiphospholipid antibodies remained high, and TEE showed a 7×8 mm area of mitral vegetation. A TEE results from his first admission revealed a 5×6 mm area of mitral vegetation, which was believed to be related to the current vegetation. As anticoagulation produced no improvement, the mitral valve was replaced with a mechanical valve. Examination of the excised vegetation found it to be consistent with LS. The patient made good progress within 3 years after surgery. CONCLUSIONS LS size can increase despite anticoagulation in cases with high titers of all 3 antiphospholipid antibodies and cerebral infarction. Such patients require ongoing TEE follow-up and surgical treatment should be considered.

Figure 1.

(A–1) Head MRI of our patient’s first cerebral infarction showed hyperintensity (circle) in diffusion-weighted images (A–2) and low intensity (circle) on an apparent diffusion coefficient map, along bilateral anterior and posterior circulation lesions. (B–1) Head MRI of the recurrence of our patient’s cerebral infarction showed faint hyperintensity (circle) in diffusion-weighted images (B–2) and low intensity (circle) on an apparent diffusion coefficient map, along a left parietal lesion (TR/TE): (4000/95). MRI – magnetic resonance imaging; TR/TE – repetition time/echo time (for the control of image contrast in weighted MRI).

Figure 2.

(A) Transesophageal echocardiography image of the patient’s first cerebral infarction, showing a 5×6 mm image of the mitral vegetation on the posterior leaflet; (B) Enlarged (to 7×8 mm) image of the recurrent cerebral infarction site; (C) No change was observed 72 days after the last cerebral infarction.

Figure 3.

(A) Macroscopy of the mitral vegetation in the tissue sample of the patient. (B) Hematoxylin & eosin stain of the histopathological mitral vegetation tissue showing an organized fibrin thrombus with no neutrophilic infiltration (×20 magnification), consistent with Libman-Sacks endocarditis.