Non-bacterial thrombotic endocarditis manifested by ventricular fibrillation in a patient with low grade ovarian carcinoma: case report and literature review

Abstract

Background: Non-bacterial thrombotic endocarditis (NBTE) is a rare form of endocarditis notably described in patients with advanced malignancy and auto-immune diseases. It is characterized by the formation of sterile, fibrin-containing vegetations on cardiac endothelium, in the absence of positive blood cultures. It is predominantly located on the mitral- and aortic valve (AV). Vegetations in NBTE are prone to embolize. Trousseau syndrome (TS) is defined as unexplained thrombotic events that precede the diagnosis of malignancy.

Case summary: A 49-year-old pre-menopausal woman with a history of visual disturbances, recurrent deep vein thrombosis (DVT) with concurrent pulmonary emboli (PE), and uterine myomas with dysfunctional uterine bleeding was resuscitated for ventricular fibrillation. While echocardiography revealed vegetations on the AV, blood cultures remained negative. Additional work-up for the aetiology of sterile vegetations revealed a low-grade ovarian carcinoma. Cardiac analysis showed evidence of myocardial infarction in the absence of coronary atherosclerosis as a cause for ventricular fibrillation.

Discussion: Unexplained thrombotic events (venous, arterial, or both) warrant further investigation, e.g., with regard to TS. NBTE is a potential source of thromboembolism in TS and a rare ante-mortem finding, which prompts additional investigation of the underlying cause. In our patient, a triad of (suspected) (i) arterial/systemic embolization (i.e. visual disturbances, splenic infarction, coronary embolism), (ii) peripheral thrombophlebitis/hypercoagulability (i.e. DVT and PE), and (iii) malignancy (i.e. gynaecological abnormalities) raised suspicion of NBTE in the setting of TS. Early diagnosis and treatment of NBTE is of importance due to the high incidence of embolization, with possible fatal outcome.

Keywords: Anticoagulation; Case report; Literature review; Myocardial infarction; Non-bacterial thrombotic endocarditis; Ovarian carcinoma; Trousseau syndrome; Ventricular fibrillation.