Inadvertent left ventricular pacing due to lead malpositioning, incidentally discovered seventeen years later.

Inadvertent lead malpositioning into the left ventricle (LV) is an uncommon complication of pacemaker lead implantation. It can have implications on clinical outcome due to ventricular dyssynchrony, and result in further complications such as thrombus formation with subsequent embolisation. This case study reports the clinical, electrocardiographic, plain film and echocardiographic findings of an 82-year-old male in whom the intravenous lead of a dual chamber pacemaker was unintentionally passed into the LV via an atrial septal defect. Inadvertent placement was discovered incidentally following the onset of atrial fibrillation (AF) 17 years later.