Cardiac magnetic resonance parameters and ventricular tachycardia recurrence after catheter ablation: a systematic review and meta-analysis.
BACKGROUND Cardiac magnetic resonance (CMR) may provide insights into arrhythmogenic substrate in patients undergoing ventricular tachycardia (VT) ablation, but its prognostic value remains uncertain. METHODS We performed a systematic review and meta-analysis, following PRISMA guidelines, of available studies comparing CMR-derived parameters in patients with and without VT recurrence after ablation, from inception to March 2026. Primary outcomes included functional parameters - left ventricular ejection fraction (LVEF) and left ventricular (LV) mass, while secondary outcomes included ventricular volumes and late gadolinium enhancement (LGE) derived structural characteristics. Random-effects models were applied. RESULTS Seven studies including 415 patients were analyzed, with 36.1% experiencing VT recurrence. Lower LVEF was associated with recurrence in the primary analysis (mean difference: - 4.41%; 95% CI: - 8.66 to - 0.16; p = 0.044; I²=27.3%), however, this finding was not robust in leave-one-out analysis. No significant associations were observed for LV mass or ventricular volumes. Among structural parameters, transmural, epicardial, or septal LGE were not associated with recurrence. CONCLUSION Available evidence suggests that CMR-derived parameters have limited and inconsistent associations with VT recurrence after catheter ablation. Although reduced LVEF may be associated with recurrence, this finding was not robust in sensitivity analyses, while structural CMR characteristics showed no consistent associations. Larger prospective studies using standardized CMR protocols and time-to-event analyses are needed to better define the prognostic role of CMR.