Ventricular fibrillation resulting from diaphragmatic stimulation during gastric bypass surgery

Gastric bypass operations are common and severely obese patients are prone to arrhythmias, particularly atrial fibrillation. Intraoperative ventricular arrhythmias during bariatric surgery have not been reported previously.

A 35-year-old, severely obese, diabetic woman with no other prior medical history underwent thorough preoperative cardiovascular evaluation before having laparoscopic Roux-en-Y gastric bypass. Intraoperatively she developed sudden onset ventricular fibrillation during the use of unipolar electrocautery near the Angle of His. The procedure was aborted, and the patient underwent repeat cardiovascular assessment including coronary angiography and serial electrophysiology studies before being unremarkably re-operated 6 months later, at which time a harmonic scalpel was used for dissection. 12 months post operation, the patient remains asymptomatic.

Owing to the proximity of the right ventricle overlying the diaphragm, far-field stimulation was likely responsible for inducing VF.