Pyloric obstruction secondary to epicardial pacemaker implantation: a case report.

A 10-year old Lhasa Apso dog was presented for an acute history of exercise intolerance and hind limb weakness. High grade second degree atrioventricular block with an atrial rate of 200 beats per minute, ventricular rate of 40 beats per minute and an intermittent ventricular escape rhythm, was diagnosed on electrocardiograph. A transdiaphragmatic, unipolar, epicardial pacemaker was implanted without immediate surgical complications. Severe vomiting was noted 12 h post-operatively. Abdominal ultrasound and a barium study supported a diagnosis of pyloric outflow obstruction and exploratory abdominal surgery was performed. The pyloric outflow tract appeared normal and no other causes of an outflow obstruction were identified. The epicardial generator was repositioned from the right to the left abdominal wall. Pyloric cell pacing was presumed to be the cause for the pyloric obstruction and severe vomiting, and this was thought to be due to close proximity of the pacemaker generator to the pylorus situated in the right abdominal wall. Repositioning of the pulse generator to the left abdominal wall resulted in resolution of vomiting.