BACKGROUND Direct comparisons of combined (C-ABL) and non-combined (NC-ABL) endo-epicardial ventricular tachycardia (VT) ablation outcomes are scarce. We aimed to investigate the long-term clinical efficacy and safety of these 2 strategies in ischemic heart disease (IHD) and nonischemic cardiomyopathy (NICM) patients. METHODS Multicentric observational registry including 316 consecutive patients who underwent catheter ablation for drug-resistant VT between January 2008 and July 2019. Primary and secondary efficacy endpoints were defined as VT-free survival and all-cause death after ablation. Safety outcomes were defined by 30-days mortality and procedure-related complications. RESULTS Most of the patients were male (85%), with IHD (67%) and mean age of 63±13 years. During a mean follow-up of 3±2 years, 117 (37%) patients had VT recurrence and 73 (23%) died. Multivariate survival analysis identified electrical storm (ES) at presentation, IHD, left ventricular ejection fraction (LVEF), New York Heart Association (NYHA) class III/IV, and C-ABL as independent predictors of VT recurrence. In 135 patients undergoing repeated procedures, only C-ABL and ES were independent predictors of relapse. The independent predictors of mortality were C-ABL, ES, LVEF, age and NYHA class III/IV. C-ABL survival benefit was only seen in patients with a previous ablation (P for interaction=0.04). Mortality at 30-days was similar between NC-ABL and C-ABL (4% vs. 2%, respectively, P=0.777), as was complication rate (10.3% vs. 15.1% respectively, P=0.336). CONCLUSION A combined endo-epicardial approach was associated with greater VT-free survival and lower all-cause death in IHD and NICM patients undergoing repeated VT catheter ablations. Both strategies seem equally safe.

Introduction: Cardiac autonomic system modulation by endocardial ablation targeting atrial ganglionated plexi (GP) is an alternative strategy in selected patients with severe functional bradyarrhythmias, although no consensus exists on the best ablation strategy. The aim of this study was to evaluate if a simplified approach by a purely anatomical guided ablation of just the atrial right GP is enough for the treatment of these patients. Methods: We prospectively enrolled patients with significant functional bradyarrhythmias and performed endocardial ablation purely guided by 3D electroanatomic mapping directed at the atrial right GP and accessed parameters of parasympathetic modulation and recurrence of bradyarrhythmias. Results: Thirteen patients enrolled (76.9% male, median age 51, 42-63 years). After ablation, a median RR interval shortening of 28.3 (25.6–40.3)% occurred (111, 937.5-1395.4ms to 722.9, 652.2-882.4ms, p=0.0015). The AH interval also shortened (19, 10.5–35.7%) significantly after the procedure (115, 105-122ms to 85, 71-105ms, p=0.002) as well as Wenckebach cycle length (11.1, 5.9–17.8% shortening) from 450, 440-510ms to 430, 400-460ms, p=0.0014. On 24-hour Holter monitoring there was significant increase in heart rates (HR) of patients after ablation (minimal HR increased from 34 (26-43)bpm to 49 (43–56)bpm, p=0,0063 and mean HR from 65 (47-72)bpm to 78 (67-87)bpm, p=0.0015). No patients had recurrence of symptoms or significant bradyarrhythmias during a median follow-up of 8.4 months. Conclusions: A purely anatomic guided procedure directed only at the atrial right ganglionated plexi seems to be enough as a therapeutic approach for cardiac parasympathetic modulation in selected patients with significant functional bradyarrhythmias.

Background and aims: Cardiac magnetic resonance (CMR), has shown conflicting data regarding existence of structural abnormalities in patients with idiopathic premature ventricular contractions (PVCs) from the right ventricular outflow tract (RVOT). Our aim was to evaluate the prevalence of low voltage areas (LVA) in the RVOT of patients with PVCS from the outflow tract and in a control group. Secondly, assess for the presence of a non-invasive electrocardiographic (ECG) marker. Methods: 56 consecutive patients, 45 with frequent PVCs (>10000/24h) LBBB, vertical axis, negative in aVL and 11 subjects without PVCs. Arrhythmogenic right ventricular cardiomyopathy was ruled out in all patients. An ECG was performed with V1-V2 at the 2nd intercostal space and the presence of a Brugada ECG pattern (BrP) was assessed. Bipolar voltage map of the RVOT was performed in sinus rhythm (0.5 mV-1.5 mV colour display). Areas with electrograms < 1.5 mV represented the LVA. We tested for the association between high BrP and LVA. Results: None of the patients in the control group had BrP or LVA. In the PVC group, 29 patients (64%) had type 2 BrP and 28 (62%) had LVAs. LVAs were more frequent in patients with BrP; 93% versus 4%, p<0.0001, which was associated with LVA, OR (95% CI): 202.50 (16.92- 2423), p<0.0001. Conclusions: LVAs were frequently present in the RVOT of patients with idiopathic PVCs. They were absent in controls and can be unmasked by the presence of BrP in high right precordial leads.