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 ± 860.6 days, 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) > 163.5 mL had significant predictive value for VT/VF recurrence (area under the curve: 0.602, p = 0.041). Moreover, the percentage of patients with LVEDV >163.5 mL 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 > 163.5 mL (p = 0.012) and QRS width > 125 msec (p = 0.049) were significant predictors for VT/VF recurrence by univariate Cox regression analysis. However, only LVEDV > 163.5 mL (hazard ratio: 2.549, 95% confidence interval: 1.249 ~ 5.201, p = 0.010) and QRS width > 125 msec (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 > 125 msec were independent predictors for VT/VF recurrence in secondary prevention ICD recipients under optimal medical therapy, independent of LV ejection fraction.