Boldizsar Kovacs, Leon Dinshaw, Alvaro Marco Del Castillo, Christiane Jungen, Stefan Kurath-Koller, Stefan Stojković, Francesco Santoro, Giacomo Mugnai, Laura Perrotta, Rachel M A Ter Bekke, Kevin Vernooy, Paul G A Volders, Bert Vandenberk
In NICM patients with LVEF > 35%, noninducibility after CA predicts favourable arrhythmic outcomes. Non-circumferential mid-myocardial late gadolinium enhancement with septal involvement, and inducibility after VT ablation, identify higher-risk patients.
BACKGROUND: Patients with nonischemic cardiomyopathy (NICM) are at risk for sustained ventricular tachycardia (VT). Implantable cardioverter-defibrillators (ICDs) are guideline-recommended for secondary prevention, but the necessity of routine ICD implantation after successful catheter ablation (CA) in patients with preserved or mildly reduced left ventricular ejection fraction (LVEF > 35%) remains uncertain. This review summarizes the current evidence.
METHODS: A PROSPERO-registered systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, Embase, and Cochrane were searched through June 2025. Studies including adults with NICM and LVEF > 35% undergoing CA for sustained monomorphic VT were eligible. Data on patient characteristics, ablation outcomes, VT recurrence, mortality, and ICD therapies were extracted. Results were descriptively synthesized, and weighted means were calculated when feasible.
RESULTS: Eleven studies (1995-2024), including 1430 patients, were identified; 936 (66%) were analyzable. The weighted mean LVEF was 38% ± 14%; mean age was 59 ± 14 years. Sustained VT recurrence ranged from 14%-67% during a weighted mean follow-up period of 608 ± 745 days. Procedural noninducibility consistently predicted lower recurrence rates (18%-32%), than those in inducible patients (up to 75%). Two studies using cardiac magnetic resonance imaging found non-circumferential mid-myocardial late gadolinium enhancement with septal involvement associated with higher recurrence risk. Risk of bias was moderate to serious.
CONCLUSIONS: In NICM patients with LVEF > 35%, noninducibility after CA predicts favourable arrhythmic outcomes. Non-circumferential mid-myocardial late gadolinium enhancement with septal involvement, and inducibility after VT ablation, identify higher-risk patients.
REGISTRATION: PROSPERO CRD420251075109.