A 41-year-old man who had a history of suicide attempt by self-stabbing of the chest at the age of 15 and surgical repair of the stab wound of the heart was transferred to a neurosurgical hospital suffering from right hemiparesis. Stroke was diagnosed and he successfully underwent endovascular thrombectomy but postoperative computed tomography revealed left ventricular aneurysm and intracavitary thrombus that could have caused the embolic stroke. He was transferred to our hospital for cardiac surgery to prevent another embolization. Although an emergency operation had been attempted for the large and mobile thrombus, the patient was carefully observed for 4 weeks prior to surgery because of acute and huge stroke with a high risk of perioperative intracranial hemorrhage. After a fortunately uneventful observation, thrombectomy with left ventriculoplasty was performed successfully and the postoperative course was uneventful without neurological impairment. To prevent a fatal embolic event, postoperative follow-up after successful repair of cardiac injury is mandatory.