Nonbacterial thrombotic endocarditis of the tricuspid valve with recurrent pulmonary embolism in a patient with pancreatic adenocarcinoma: a case report

Nonbacterial thrombotic endocarditis is a rare condition that is typically asymptomatic and is most often diagnosed post mortem in patients with cancer, systemic lupus erythematosus, or antiphospholipid syndrome. In this condition, vegetations are predominantly localized in the left heart. In contrast, isolated involvement of the tricuspid valve in nonbacterial thrombotic endocarditis is extremely rare, and the the incidence of this localization has not been established. This article presents a clinical case of nonbacterial thrombotic endocarditis in a patient with pancreatic cancer and liver metastases, characterized by a rare variant of isolated tricuspid valve involvement and manifested by recurrent episodes of pulmonary embolism despite ongoing anticoagulant therapy. The complexity of this case was due to recurrent pulmonary embolism following any attempt of even short-term discontinuation of anticoagulant therapy. At the same time, withdrawal of anticoagulation was a mandatory prerequisite for the safe biopsy of a metastatic lesion and subsequent histological verification, without which adequate antitumor therapy could not be initiated. Given the limited amount of available data on the management of such patients, the therapeutic approach requires individualization and nonstandard clinical decision-making by the treating physician.