Daniel Musikantow

and 10 more

Background: Modulation of the cardiac autonomic nervous system (ANS) is a promising adjuvant therapy in the treatment of atrial fibrillation (AF). In pre-clinical models, pulsed field (PF) energy has the advantage of selectively ablating the epicardial ganglionated plexi (GP) that govern the ANS. Objective: This study aims to demonstrate the feasibility and safety of epicardial ablation of the GPs with PF during cardiac surgery with a primary efficacy outcome of prolongation of the atrial effective refractory period (AERP).  Methods: In a single-arm, prospective analysis, patients with or without a history of AF underwent epicardial GP ablation with PF during coronary artery bypass grafting (CABG). AERP was determined immediately pre- and post- GP ablation to assess cardiac ANS function. Holter monitors were performed to determine rhythm status and Heart Rate Variability (HRV) at baseline and at 1 month post-procedure.   Conclusions:  This study demonstrates the safety and feasibility of epicardial ablation of the GP using PF to modulate the ANS during cardiac surgery. Large, randomized analyses are necessary to determine whether epicardial PF ablation can offer a meaningful impact on the cardiac ANS and reduce AF. Results: Of 24 patients, 23 (96%) received the full ablation protocol. No device-related adverse effects were noted. GP ablation resulted in a 20.7% ± 19.9% extension in AERP (P < 0.001). Post-operative AF was observed in 7 (29%) patients. Holter monitoring demonstrated an increase in mean heart rate (74.0±8.7 vs 80.6±12.3, P=0.01). There were no significant changes in HRV. There were no study-related complications.

Connor Oates

and 10 more

Background: Increasing interest in physiological pacing has been countered with challenges such as accurate lead deployment and increasing pacing thresholds with His-bundle pacing (HBP). More recently, left bundle branch area pacing (LBBAP) has emerged as an alternative approach to physiologic pacing. Objective: To compare procedural outcomes and pacing parameters at follow-up during initial adoption of HBP and LBBAP at a single center. Methods: Retrospective review, from September 2016 to January 2020, identified the first 50 patients each who underwent successful HBP or LBBAP. Pacing parameters were then assessed at first follow-up after implantation and after approximately one year, evaluating for acceptable pacing parameters defined as sensing R-wave amplitude >5 mV, threshold <2.5 V @ 0.5 ms and impedance between 400 and 1200 Ohms. Results: The HBP group was younger with lower ejection fraction compared to LBBP (73.2±15.3 vs 78.2±9.2 years, p=0.047; 51.0±15.9% vs 57.0±13.1%, p = 0.044). Post-procedural QRS widths were similarly narrow (119.8±21.2 vs. 116.7±15.2ms; p = 0.443) in both groups. Significantly fewer patients with HBP met the outcome for acceptable pacing parameters at initial follow-up (56.0% vs 96.4%, p = 0.001) and most recent follow-up (60.7% vs 94.9%, p = <0.001; at 399±259 vs. 228±124 days, p = <0.001). More HBP patients required lead revision due to early battery depletion (0 vs 13.3%, at an average of 664 days). Conclusion: During initial adoption, as compared with LBBAP, HBP is associated with a significantly higher frequency of unacceptable pacing parameters, energy consumption, and lead revisions.