Renal emboli and atrial septal aneurysm.

A 53-year-old woman presented with flank pain and hematuria. She was suspected of having a renal stone but instead was found to have segmental renal infarction. Further evaluation revealed an atrial septal aneurysm, which was presumed to be the source of an embolism. Renal emboli should be considered when more common cause of flank pain are excluded. Atrial septal aneurysm should be considered when embolic events occur without an evident source. Transesophageal echocardiography is the best test to diagnose atrial septal aneurysms.