Multiple systemic emboli complicating the course of a patient with an atrial septal defect, an atrial septal aneurysm and an endocardial right atrial pacemaker lead.

We describe an adult patient with a large atrial septal defect, an atrial septal aneurysm and thrombus formation on a transvenous right atrial pacing lead. Because of right-to-left shunting through the atrial septal defect, she developed multiple systemic emboli to the spleen and left kidney (with infarcts), to the left leg, and probably to the brain as a cerebrovascular accident. The fundamental guiding principle of avoiding endocardial pacing leads in patients with congenital intracardiac communications, was violated in this patient, leading to serious dire consequences and complications.