Cardioneural Temporary Pacing to Achieve Autonomic Modulation

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.