Meta-analysis comparing outcomes of catheter ablation for ventricular arrhythmiain ischemic versus nonischemic cardiomyopathy.

BACKGROUND Catheter ablation is an effective treatment for VA in ICM. However, results in NICM patients are not satisfactory, and studies comparing differences between NICM and ICM are limited. We conducted a meta-analysis of procedural characteristics and long-term outcomes of catheter ablation for ventricular arrhythmia (VA), comparing results between ischemic cardiomyopathy (ICM) and nonischemic cardiomyopathy (NICM). METHODS Studies in the PubMed, EMBASE, and Cochrane databases were systematically reviewed. Four studies reporting comparison of catheter ablation of VA between ICM and NICM were examined. The Newcastle-Ottawa Scale was used to appraise study quality. A random-effects model with inverse variance method was used for comparisons. RESULTS Epicardial approach was significantly more undertaken for the NICM group than in the ICM group (OR: 0.13; 95% CI: 0.09 to 0.18; P < 0.00001). Mean ablation time (P  =  0.54), fluoroscopy time (P  =  0.55), and procedural time (P  =  0.18) did not differ significantly between the ICM and NICM groups. Procedural failure rates (OR: 0.46; 95% CI: 0.24 to 0.89; P  =  0.02) and VA recurrence rates (RR: 0.68; 95% CI: 0.46 to 1.01; P  =  0.06) were significantly higher in the NICM group than in the ICM group. However, all-cause mortality (RR: 1.37; 95% CI: 0.75 to 2.49; P  =  0.31) did not differ significantly between groups. CONCLUSIONS Procedural failure and VA recurrence rates were significantly higher in the NICM group, despite significantly more frequent epicardial access. These highlight the limitations of catheter ablation for VA in NICM, given our current knowledge. This article is protected by copyright. All rights reserved.