Case Report
A 59-year-old man with history of chronic obstructive pulmonary disease presented to the emergency room with severe sinus bradycardia and hypotension. He was diaphoretic and denied any chest pain. He gave a history of recurrent dizziness and near syncopal episodes. The patient was not on any atrioventricular nodal blocking agents and initial blood work showed no reversible cause of his severe sinus bradycardia.
The patient was started on intravenous fluid hydration and a bedside echocardiogram was obtained. Echocardiogram showed normal biventricular systolic function and no significant valvular abnormalities. Atropine was given but resulted in minimal, transient improvement in his heart rate to the low 50s. The systolic blood pressure remained below 80 mmHg. Dopamine followed by norepinephrine drips were administered and the patient was sent to the electrophysiology lab for dual chamber permanent pacemaker therapy.
During implantation of a permanent pacemaker, the right atrial lead was appropriately placed via the left subclavian vein into the right atrial appendage. However, the ventricular lead was placed via the subclavian artery into the left ventricular cavity. He was admitted to the hospital overnight and a chest x-ray was obtained the next day, showing no evidence of pneumothorax (Figure 1 ). Surprisingly, his ECG showed atrial pacing with long AV delay and intermittent ventricular pacing with the paced ventricular beats showing right bundle branch block morphology contrary to the expected left bundle branch block morphology seen when the lead is inside the right ventricular cavity (Figure 2 ). A limited bedside Echo was obtained that showed the ventricular lead clearly crossing the aortic valve to the left ventricular cavity and fixed into the inferolateral wall of the left ventricle (Figure 3 ). Early recognition of this serious pacemaker implantation complication led to pacemaker revision in the same day with extraction of the arterial lead and reinsertion of the ventricular lead via the left subclavian vein into the right ventricular cavity (Figure 4 ). The pacemaker revision went uncomplicated.