Abstract Body (Do not enter title and authors here): A 42-year-old female with SLE, lupus cerebritis with related seizure disorder, and mesenteric venous thrombosis on warfarin initially presented for syncope. Acute stroke workup was negative, and syncope was attributed to possible brief seizure. Six months later, the patient was evaluated by cardiology for hypertension diagnosed during hospitalization. She reported no further syncope, but exam revealed a 3/6 holosystolic murmur. Subsequent TTE identified severe MR with primary MV degeneration and LVEF >60%. A TEE confirmed severe MR with myxomatous MV leaflets and moderate-sized nonmobile vegetations attached to the atrial side of A2 and P2 of the MV. Subsequent infectious workup including serial blood cultures were negative. The patient was diagnosed with non-bacterial Libman-Sacks endocarditis (LSE). Given a lack of symptoms and plan to resume immunosuppressive therapy and continue her anticoagulation (AC), surgical intervention was initially deferred with close follow-up.

The patient continued to endorse worsening headaches and brain MRI revealed new chronic small ischemic strokes. One morning, the patient noted sudden aphasia and presented to the ED. Stroke workup revealed an acute ischemic stroke with total left M2 occlusion of her MCA, and she underwent thrombectomy. Cerebral angiogram further revealed FMD. Given ongoing embolic phenomena, likely from LSE, she underwent MVR with mechanical valve and LA appendage ligation and continued mycophenolate and warfarin. Two months postoperatively, the patient remained asymptomatic with normal prosthetic valve function and neurologic status. However, evaluation for extracranial FMD with CTA revealed interval development of PV vegetations. These lesions and moderate PR were confirmed on TTE.

Discussion: While response to immunosuppressive therapy and AC has been reported to improve early-phase LSE, this patient continued to experience thromboembolic events resulting from LSE vegetations while on mycophenolate and warfarin. Despite continuing these therapies after MVR, she later developed PV vegetations and PR. Pulmonary valve involvement is rare in LSE, and development of new disease while on recommended medical therapy represents unusual disease progression.