Left ventricle remodeling predicts the recurrence of ventricular tachyarrhythmias in implantable cardioverter defibrillator recipients for secondary prevention

Background: Implantable cardioverter defibrillator (ICD) is an effective treatment for secondary prevention of ventricular tachycardia/ventricular fibrillation (VT/VF). Left ventricular (LV) remodeling may develop before ICD implant and over time. However, it remains unclear how LV remodeling affects subsequent risk for recurrence VT/VF in ICD recipients under optimal medical therapy. Methods: From May of 2004 to June of 2015, 144 patients received ICD implantation for secondary prevention were enrolled in this study. All information interrogated from ICD devices during follow-up or ICD therapy history (anti-tachycardia pacing and shock therapy) were reviewed and validated the occurrences of VT/VF. Results: At a mean follow-up of 1110.5±860.6days, 53 patients (36.8%) had recurrence of VT/VF episodes and 91 patients had no recurrence of VT/VF episode after ICD implant. Left ventricular end-diastolic volume (LVEDV)>163.5mL had significant predictive value for VT/VF recurrence (area under the curve: 0.602, p=0.041). Moreover, the percentage of patients with LVEDV >163.5mL was significantly higher in patients with recurrent VT/VF than patients without recurrent VT/VF (62.3 vs 40.0%, p=0.010). Left ventricular ejection fraction≤30% (p=0.031), LVEDV>163.5mL (p=0.012) and QRS width>125msec (p=0.049) were significant predictors for VT/VF recurrence by univariate Cox regression analysis. However, only LVEDV>163.5mL (hazard ratio: 2.549, 95% confidence interval: 1.249~5.201, p=0.010) and QRS width>125msec (hazard ratio: 2.173, 95% confidence interval: 1.030~4.586, p=0.042) were independent predictors for recurrence of VT/VF after multivariable adjustment. Conclusion: LV remodeling and QRS width>125msec were independent predictors for VT/VF recurrence in secondary prevention ICD recipients under optimal medical therapy, independent of LV ejection fraction.