Anatomical ablation using a dual-energy contact force-sensing focal ablation catheter vs standard radiofrequency ablation catheter for persistent atrial fibrillation: a comparative prospective study

Background

Large registries and clinical trials have demonstrated the efficacy and safety of pulsed field ablation (PFA) for pulmonary vein isolation (PVI) in patients with paroxysmal atrial fibrillation (AF). To date, most PFA studies have been conducted using single-shot or large-footprint devices which have a limited versatility to perform lesions beyond PVI.

Purpose

We aimed at investigating PF ablation using a dual-energy contact force-sensing focal ablation catheter in patients with persistent AF.

Methods

40 consecutive patients undergoing a first-time ablation for persistent atrial fibrillation were enrolled. The lesion set comprised PVI, linear ablation (dome, mitral and CTI) and systematic VOM-OH. Dual-energy contact force-sensing focal ablation catheter was used in the PF group (20 patients). In this group posterior lesions during PVI and left linear lesions were performed using PFA whereas RF was employed elsewhere (anterior PVI, CTI line). To evaluate effectiveness of PFA for the mitral line, the last 10 patients of each group had the VOM-OH performed after catheter ablation.

The control group comprised a series of 20 consecutive patients who received the same lesions set with RF only.

The primary endpoint of the study was the rate of first pass PVI and lines block.

Results

To date, a total of 37 patients were included in the study (20 PF and 17 RF group). The two groups were comparable for most baseline characteristics.

The majority of procedures were performed under local anesthesia both in the PF and RF (85% vs 94%,) group with similar total (190±20 vs 191±21 minutes), and fluoroscopy (20±6 vs 20±5) duration (all p=ns). The ablation time was longer in the PF group (52±9 vs 41±7, p<0.0001). The all set was blocked during the first pass in 55% of PF and in 12% of RF group (p=0.004). The first pass PVI and dome block was obtained more often in the PF group compared to RF (80% vs 40%, p=0.015). The rates of PVI and dome block (90% vs 70%) as well as the complete set block (90% vs 70%) at the end of the procedure were similar in both groups (all p=ns). The block at the mitral isthmus was achieved in all patients at the end of the procedure irrespective of the energy and of the timing of VOM-EI. The lesions set could be completed in all procedures both under general and local anesthesia. One circumflex artery spasm, which resolved spontaneously, occurred during ablation inside the coronary sinus in the PF group despite preventive intravenous nitrates.

Conclusions

A dual-energy focal tip contact force-sensing ablation catheter embedded in a 3-D mapping system is effective and safe to acutely isolate the pulmonary veins and to block the conduction through the dome, CTI and mitral isthmus. PFA is feasible under local anesthesia and it seems more effective than RF to obtain transmural lesions at the posterior wall during PVI and floor line.Acute results in RF and PG groups