A 70-year-old man had an episode of dyspnoea followed by syncope 2 months after a stroke. Deep venous thrombosis was found in his right lower extremity by venous Doppler ultrasound. Transoesophageal echocardiography revealed a 33×38 mm highly mobile mass floating in his right atrium with no attachment to any atrium structure (fig 1A). The right heart chambers were dilated with mild tricuspid valve regurgitation and a systolic pulmonary artery pressure of …