Significance of atrial septal aneurysm: report of a case.

Postoperative stroke can have many etiologies including cerebral thrombosis, embolism, and hemorrhage. If there is a right-to-left intracardiac shunt, paradoxical embolism may also occur. Atrial septal aneurysm has been diagnosed with increasing frequency because of the accuracy of transesophageal echocardiography (TEE). Atrial septal aneurysm is also associated with patent foramen ovale and atrial septal defects. We report a case of a patient who developed a postoperative stroke one day after coronary artery bypass surgery. TEE performed in the intensive care unit revealed an atrial septal aneurysm with a right-to-left interatrial shunt, which may have resulted in paradoxical systemic embolism.