Abstract Body (Do not enter title and authors here): Background: Patients undergoing epicardial access for ventricular tachycardia (VT) have a higher rate of complications and VT recurrence post-procedure. Data regarding electrophysiological factors driving the outcomes are scant.
Objective: To compare the factors and outcomes associated with epicardial vs endocardial VT ablation.
Methods: A single-center, retrospective study of patients undergoing catheter ablation for scar-related VT was conducted. Data collected included demographics, comorbidities, medications, relevant laboratory abnormalities, electrocardiograms, echocardiograms, detailed procedural characteristics, and outcomes.
Results: Our cohort of 554 patients had 89 (16.1%) epicardial and 465 (83.9%) endocardial VT ablations. Patients undergoing epicardial ablation had a greater frequency of NICM, and more patients had undergone sympathetic modulation for VT (p < 0.05) but had lesser frequency of valve surgery, and CABG. Epicardial ablation was associated with greater use of both short-term (<3 months) and long-term (>6 months) anti-arrhythmic drugs (AAD) (p<0.01). Epicardial access was obtained by micropuncture or needle-in-needle technique for 22.5% (n=20) of patients. Except for more use of general anesthesia and the lesser usage of drugs for VT induction during epicardial procedures, there were no significant differences. Epicardial ablation had a higher risk of acute complications (<30 days) after the procedure (driven by pericarditis) (25% vs 7.8%, p<0.01). On survival analysis, epicardial access was associated with an increase in VT recurrence and repeat ablation (p<0.01) during a mean follow-up of 1072 days. On multivariate analysis, after adjusting for age, sex and comorbidities, epicardial access was an independent predictor of VT recurrence or repeat ablation [aHR 1.61 (CI: 1.18- 2.2)]
Conclusion: Patients undergoing epicardial ablations with fewer comorbidities demonstrated increased AAD usage prior to and after the procedure, and a higher risk of acute complications after the procedure. Epicardial access was an independent predictor of VT recurrence or repeat ablation.