Ventricular tachycardia ablation in structural heart disease with LV-EF35%: impact of cardiomyopathy type on outcomes and ICD therapy

Abstract Background In patients with structural heart disease (SHD) and moderately impaired left ventricular ejection fraction (LVEF 35 %), the benefit of catheter ablation for ventricular tachycardia (VT) and the subsequent need for ongoing implantable cardioverter-defibrillator (ICD) therapy remain uncertain. Purpose To assess the incidence and predictors of VT recurrence after catheter ablation in patients with SHD and LVEF 35 %, and to explore implications for the continued need of ICD therapies after successful ablation. Methods A total of 226 consecutive patients with SHD and LVEF 35 % underwent VT ablation: 89 with ischaemic cardiomyopathy (ICM) and 137 with non-ischaemic cardiomyopathy (NICM). Baseline characteristics, ablation strategy, procedural success, and follow-up outcomes were compared between both groups. Nearly all patients (99 %) had an ICD at the time of ablation. Results ICM patients were older, more frequently hypertensive, and had slightly lower LVEF. Almost all ICM procedures were endocardial-only, whereas 27 % of NICM cases required combined endo-epicardial access (p 0.001). Acute non-inducibility was achieved more often in ICM (92 %) than in NICM (65 %; p 0.001). Complications were infrequent and comparable between groups (7 % overall; p = 0.67). During follow-up, VT recurrence occurred in 35 % of patients, higher in NICM (43 %) than in ICM (24 %; p = 0.003), with repeat ablation required in 15 % (19 % vs 9 %; p = 0.04). Scar localisation analysis showed that VT recurrence was associated with extensive basal–inferolateral and often epicardial scars, frequently spanning multiple LV regions or both ventricles. Of all evaluated variables, only cardiomyopathy type predicted VT recurrence. Conclusion VT ablation in patients with SHD and LVEF 35 % is safe and effective, but recurrence remains frequent, especially in NICM, reflecting a more complex arrhythmic substrate. ICM patients achieved high acute success and durable VT control. In this subgroup, the long-term need for ICD therapies after successful ablation may warrant individual reassessment. Figure 1. Kaplan–Meier curves showing freedom from VT recurrence after catheter ablation in patients with structural heart disease and LVEF 35 %. Recurrence was significantly higher in non-ischaemic (green line) compared with ischaemic cardiomyopathy (blue line, log-rank p = 0.002).