Pacemaker Implantation

This prospective observational study evaluates the burden of Atrial High-Rate Episodes (AHRE) in patients without a prior history of atrial fibrillation who undergo concurrent Bachmann Bundle Area Pacing (BBAP) and Left Bundle Branch Pacing (LBBP). Physiological pacing at these sites aims to improve interatrial conduction and reduce the risk of atrial arrhythmias. The study includes a comparative assessment across three patient groups: 1. BBAP + LBBP (physiological pacing group) 2. Right Atrial Appendage (RAA) pacing + LBBP 3. Conventional pacing - RAA and Right Ventricular (RV) pacing AHRE burden will be quantified via device diagnostics and remote monitoring at 3, 12 and 24 months post-implantation. Episodes will be classified by duration (0-6 min, 6-24 h, \>24 h), differentiating subclinical AHRE from clinically documented AF. Secondary analyses include electrocardiographic changes (P-wave indices), the need for antiarrhythmic therapy, and comprehensive echocardiographic evaluation of atrial function (e.g., LA strain, conduction delays, LAVI). The study aims to determine whether physiological pacing (BBAP + LBBP) provides superior protection against AHRE development compared with RAA + LBBP and conventional pacing strategies.

Atrial fibrillation (AF) is the most common arrhythmia, with a lifetime risk of 1 in 3-5. In cases of rapid ventricular rate, patients often experience low blood pressure, making standard rate and rhythm control medications contraindicated. While cardioversion may be necessary, it is often ineffective in long-standing AF and can lead to left ventricular stunning. This creates a vicious cycle, worsening heart failure and cardiogenic shock. AV node ablation may be required, but it is irreversible and carries risks, including complications from long-term pacing. Therefore, temporary pacing may be a preferable option to allow for hemodynamic improvement and better ventricular filling. Research suggests that parasympathetic fibers innervating the AV node can modulate conduction. Ablation in these fibers has shown promise for treating vagal-mediated syncope, and high-frequency pacing may provide chronic heart rate suppression. Intermittent pacing has also been effective in reducing ventricular rates in atrial fibrillation to prevent inappropriate ICD shock. This may be potentially beneficial for patients with uncontrolled fast AF. In a proof-of-concept study with five patients, pacing at 30Hz and 10mA in the coronary sinus resulted in a dose-dependent prolongation of the ventricular cycle length during AF, with stable blood pressure and no discomfort reported. This suggests that pacing these fibers could achieve rate control without the need for medications or AV node ablation, with no complications observed. This study aims to evaluate safety and efficacy of temporary cardio-neural pacing (CNP). This is a prospective cohort study involving patients with atrial fibrillation (AF) and rapid ventricular conduction who have failed or are contraindicated for rate control with antiarrhythmic medications. Enrolled patients will be followed up for 1 month.

This is a prospective, randomized controlled (1:1) multicenter trial. The pilot study will be conducted up to three clinical sites in the United States. The primary purpose of this study is to compare the overall safety and efficacy between the leadless pacemaker and left bundle area pacing.