Effect of prophylactic intravenous amiodarone administration on reperfusion ventricular fibrillation after release of aortic cross-clamp in patients with left ventricular hypertrophy undergoing cardiopulmonary bypass surgery: study protocol for a double-blind randomized controlled trial. (Preprint)

BACKGROUND Ventricular fibrillation (VF) is a common arrhythmia occurred after the release of aortic cross-clamp (ACC) in patients undergoing cardiopulmonary bypass (CPB) surgery. Repeated defibrillation and long duration of VF could increase myocardial injuries. In patients with left ventricular hypertrophy (LVH), VF is easier to occur and more difficult to be terminated. Amiodarone, known as class III antiarrhythmic agent, has the prominent properties of converting VF and restoring the sinus rhythm. Before ACC release, administration of amiodarone has been confirmed useful to reduce occurrence of VF. However, few studies focused on the effect of amiodarone before ACC release on reducing VF in patients with LVH. OBJECTIVE This study concentrates on the efficacy of prophylactic intravenous amiodarone administration on reperfusion VF after release of ACC in patients with LVH undergoing CPB surgery. METHODS This will be a prospective, randomized, double-blind, placebo-controlled trial. The trial is to enroll 54 patients with LVH aged 18 to 75 years who will undergo CPB surgery. All eligible participants will be randomly allocated to either the amiodarone or placebo group by using the block randomization in a 1:1 ratio. The primary endpoint will be the incidence rate of VF 30 minutes after ACC release and be assessed using the Chi-square test. All data will be analyzed in accordance with the intention-to-treat principle. RESULTS This study has been approved by the Institutional Ethics Committee of the First Affiliated Hospital of Nanjing Medical University. This clinical trial protocol was developed based on the SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) 2013 Statement. CONCLUSIONS With this trial, we are hoping to demonstrate that prophylactic infusion of amiodarone before ACC release could reduce the occurrence of reperfusion VF in LVH patients. CLINICALTRIAL This study was registered on Chinese Clinical Trial Registry (http://www.chictr.org.cn/) with the ID ChiCTR2000035057