We report a young patient with a fatal cerebral embolism from an occult atrial myxoma. The patient died before echocardiography was performed and at autopsy the definite diagnosis was made. Our patient suffered from migraine of increasing frequency. The physical exercise of sexual intercourse was the precipitating factor of this fatal embolism. The importance of early echocardiography is stressed, especially in view of the recent tendency of early and aggressive stroke treatment.