Left heart pacing and cardioembolic stroke.

Three patients with inadvertently positioned left heart pacemaker leads were admitted for neurological symptoms consistent with embolic stroke. In one of them, the pacemaker lead crossed the interatrial septum, the mitral valve, and entered the left ventricle. In another it was erroneously placed through the subclavian artery, across the aortic valve, and into the left ventricular chamber. In the third patient, the right ventricular lead of a DDD pacemaker was placed in the coronary sinus and the right atrial lead crossed the interatrial septum, and intermittently entered the left ventricular cavity. Once anticoagulation was initiated, symptoms resolved; they recurred when the level of anticoagulation dropped leading to a major stroke in one of the patients. Two of the patients were on aspirin at the onset of symptoms. We believe that every approach must be considered to remove the malpositioned lead. Otherwise, full dose anticoagulation must be initiated since antiplatelet therapy alone does not confer adequate protection against stroke.