NONİSKEMİK KARDİYOMİYOPATİSİ OLAN VENTRİKÜLER TAŞİKARDİ HASTALARINDA 3 BOYUTLU HARİTALAMA SİSTEMLERİ EŞLİĞİNDE YAPILAN KATETER ABLASYONU TEDAVİSİNİN SONLANIM NOKTALARININ DEĞERLENDİRİLMESİ

Abstract

Ventricular tachycardia (VT), seen in patients with non-ischemic cardiomyopathy (NICMP), is generally resistant to medical therapy and carries a high risk of implantable cardioverter defibrillator (ICD) therapy and mortality. In recent years, catheter ablation has become an increasingly preferred and proven effective treatment method for this patient group. In our study, we evaluated the acute procedural success and long-term VT recurrence rates of catheter ablation performed with 3D mapping systems, and examined the clinical and electrophysiological factors affecting these endpoints. A total of 128 patients who underwent catheter ablation due to VT resistant to medical therapy were included in the study [90 (70.3%) males, mean age 49±16]. Of the patients, 62.5% had dilated cardiomyopathy, 28.1% had arrhythmogenic cardiomyopathy, and 9.4% had hypertrophic cardiomyopathy. Voltage mapping was performed in all patients, and 76.5% underwent epicardial mapping. Late potential mapping was performed in 97.7% of patients, and functional substrate mapping was conducted in 54.7%. The average number of mapped VTs was 1.5±0.9, and entrainment mapping was applied in 13.3% of cases. Post-ablation VT inducibility was observed in 3.1% of patients, and acute procedural success was determined to be 96.9%. A significant reduction in amiodarone use was observed after catheter ablation compared to pre-procedure levels (31.3% vs. 75.8%; p<0.001). The total complication rate was 14.8%, with intraprocedural complications occurring in 3.9% and post-procedural complications in 10.9% of cases. During a median follow-up of 31 months, VT recurrence was observed in 35.2% of patients, and 22.7% of patients died. When VT recurrence and death were evaluated together, the 12-month event-free survival rate was calculated as 71.3%, the 24-month event-free survival rate as 61.8%, and the 36-month event- free survival rate as 51.2%. Overall survival rates were 87.8% at 12 months, 81.1% at 24 months, and 75.4% at 36 months. VT recurrence rates by cardiomyopathy subtype were as follows: 33.3% in idiopathic cardiomyopathy, 36.1% in arrhythmogenic cardiomyopathy, 33.3% in hypertrophic cardiomyopathy, 0% in myocarditis-related cardiomyopathy, and 80% in valvular cardiomyopathy. In multivariate Cox regression analysis, post-ablation VT inducibility was identified as a significant risk factor for VT recurrence-free survival (HR: 11.159; p=0.003). In analyses related to overall survival, only ejection fraction was found to be a significant risk factor (HR: 0.910; p=0.004). Our study results demonstrate that with the use of high-resolution mapping systems, VT catheter ablation is associated with high success rates both in the early and long-term follow-up of symptomatic patients.