Brain embolism associated with atrial septal aneurysm

We studied the clinical significance of atrial septal aneurysm on brain embolism. Of two-hundred twenty-eight consecutive ischemic stroke patients, 128 cases were performed transesophageal echocardiography to find cardiac lesions that could be embolic sources. Three cases were diagnosed as having atrial septal aneurysm with right-to-left shunt demonstrated by contrast echocardiography under Valsalva maneuver. These cases were all diagnosed as brain embolism from clinical courses and findings from brain CT scan, and cerebral angiography. Neurosonologic study, 24 hours Holter ECG, and transthoracic echocardiography did not reveal any other embolic sources. Paradoxical embolic mechanism is supposed to have occurred in these cases. Atrial septal aneurysm often coexists with right-to-left shunt and is clinically significant as a finding suggesting paradoxical embolism.