We report a 74-year-old woman with acute heart failure and recurrent ischemic strokes as the presenting features of a nonbacterial thrombotic endocarditis complicating a gastric adenocarcinoma. The treatment only allowed a few months remission. Diagnosis of nonbacterial thrombotic endocarditis is rarely obtained while the patient is alive. Coagulation abnormalities due to the tumoral process are responsible of the valvular thrombotic process. Anticoagulation with heparin is recommended. Valvular surgery remains controversial.