Oscar Cano

and 12 more

Introduction: Conduction system pacing (CSP) has emerged as an ideal physiologic pacing strategy for patients with permanent pacing indications. We sought to evaluate the safety and feasibility of CSP in a consecutive series of unselected patients with congenital heart disease (CHD). Methods: Consecutive patients with CHD in which CSP was attempted were included. Safety and feasibility, implant tools and electrical parameters at implant and at follow-up were evaluated. Results: A total of 20 patients were included (10 with a previous device). Ten patients had complex forms of CHD, 9 moderate defects and 1 a simple defect. His bundle pacing (HBP) or left bundle branch area pacing (LBBAP) were achieved in all patients (10 HBP, 5 LBBP and 5 left ventricular septal pacing). Procedure times and fluoroscopy times were prolongued (126±82 min and 27±30 min, respectively). CSP lead implant times widely varied ranging from 4 to 115 minutes, (mean 31±28 min) and the use of multiple delivery sheaths was frequent (50%). The QRS width was reduced from 144±32 ms at baseline to 116±16 ms with CSP. Implant electrical parameters included: CSP pacing threshold 0.85±0.61V; R wave amplitude 9.8±9.2mV and pacing impedance 735±253 Ohms, and remained stable at a median follow-up of 478 days (IQR 225-567). Systemic ventricle systolic function and NYHA class (1.50±0.51 vs 1.10±0.31; p=0.008) significantly improved at follow-up. Lead revision was required in one patient at day-4. Conclusions: Permanent CSP is safe and feasible in patients with CHD although implant technique is complex.

Oscar Cano

and 6 more

Introduction:Stand-alone substrate ablation without baseline ventricular tachycardia (VT) induction and activation mapping has become a standard VT ablation strategy. We sought to evaluate the influence of baseline VT inducibility and activation mapping on ablation outcomes in patients with structural heart disease (SHD) undergoing VT ablation. Methods:This is a single center, observational and retrospective study including consecutive patients with SHD and documented VT undergoing ablation. Baseline VT induction was attempted before ablation in all patients and VT activation mapping performed when possible. Ablation was guided by activation mapping for mappable VTs plus substrate ablation for all patients. Ablation outcomes and complications were evaluated. Results: 160 patients were included (203 VT ablation procedures) and were classified in 3 groups according to baseline VT inducibility: group 1 (non inducible, n=18), group 2 (1 VT morphology induced, n=53), and group 3 (>1VT morphology induced, n=89). VT activation mapping was possible in 35%. After a median follow-up of 38.5 months, baseline inducibility of >1VT morphology was associated with a significant incidence of VT recurrence (42% for group 3 vs. 15.1% for group 2 and 5.6% for group 1, Log-rank p<0.0001) and activation mapping with a lower rate of VT recurrence (24% vs. 36.3%, Log-rank p=0.035). Independent predictors of VT recurrences and mortality were baseline inducibility of >1VT morphology (HR 12.05 IC 95% 1.60-90.79, p=0.016) and LVEF<30% (HR 2.43 IC 95% 1.45-4.07, p=0.001), respectively. Complications occurred in 11.2% (5.6% hemodynamic decompensation). Conclusions:Baseline VT inducibility and activation mapping may add significant prognostic information during VT ablation procedur