Refractory ventricular arrhythmias during aortic valve replacement and cardiac artery bypass requiring 16 attempts of electrical cardioversion: a case report

BACKGROUND: We report a patient in whom we failed to suppress ventricular fibrillation (VF) using nifekalant but succeeded using amiodarone during cardiopulmonary bypass (CPB). CASE PRESENTATION: A 65-year-old male with hemodialysis complained of dyspnea and was diagnosed with aortic valve stenosis and angina pectoris; he was opted for elective aortic valve replacement. When the aortic forceps were declamped during CPB, immediate VF was observed; several attempts of electrical cardioversion (EC) with lidocaine and landiolol and three administrations of nifekalant were temporarily effective. However, the rhythm subsequently changed to torsades de pointes. We administered 2 g of magnesium sulfate followed by three doses of amiodarone and initiated continuous infusion. Furthermore, we initiated the pacemaker and intra-aortic balloon pumping. These procedures seemed to be effective; the sinus rhythm was sustained until the end of the surgery. CONCLUSION: We experienced a cardiac surgery requiring 16 EC attempts to terminate the life-threatening arrhythmias using amiodarone.