Efficacy of an alternative positioning of intracardiac defibrillation catheters in atrial fibrillation ablation

Background

In pulmonary vein isolation (PVI) for atrial fibrillation (AF), intraoperative defibrillation is often required. Intracardiac defibrillation catheters (ICDCs) are most effective when positioned to enclose the heart between the coronary sinus (CS) and right atrium (RA) (CS/RA configuration). However, achieving this positioning via the inferior vena cava (IVC) can be challenging, and alternative configurations remain underexplored.

Methods

This study included patients with paroxysmal or persistent AF who underwent cryoballoon ablation followed by intracardiac cardioversion using an ICDC via the IVC. The catheter was initially positioned with distal electrodes in the CS and proximal electrodes in the IVC (CS-only configuration). If cardioversion failed, the catheter was repositioned to place distal electrodes in the superior vena cava (SVC configuration). A maximum of 30 J of energy was used for all cardioversion attempts.

Results

A total of 81 patients were included. Cardioversion in the CS-only configuration restored sinus rhythm in 11% (9/81) of patients. Repositioning to the SVC configuration achieved successful cardioversion in 93.1% (67/72) of the remaining cases without complications. Patients requiring the SVC configuration had a significantly higher prevalence of persistent AF (33.3% vs. 80.6%; p = 0.045). No adverse events were observed following cardioversion in the SVC configuration.

Conclusions

While the CS-only configuration offers ease of placement, its efficacy is limited. Repositioning to the SVC configuration significantly enhances cardioversion success and represents a safer, more effective alternative for ICDC use during AF ablation.