Safety and efficacy of pulsed field ablation for atrial fibrillation in patients with wild-type TTR amyloidosis: A multicentre study

Background/Introduction

Atrial fibrillation (AF) is a common finding in patients with wild-type TTR amyloidosis. AF ablation represents a cornerstone of rhythm control in this population; however, the role of pulsed field ablation (PFA) remains unclear.

Purpose

This study aimed to describe the safety and efficacy of PFA for the treatment of atrial fibrillation in patients with wild-type TTR amyloidosis.

Methods

We conducted a prospective data collection of consecutive patients who underwent PFA for AF and had a confirmed diagnosis of wild-type TTR amyloidosis. The study included three centres within a major US health system. All procedures were performed between May 2024 and May 2025. A standardised follow-up strategy was applied, including 48-hour Holter monitoring between 90 and 180 days after ablation.

The primary safety endpoint was the occurrence of procedural complications. The primary efficacy outcomes were acute procedural success and AF-free survival at six months after a blanking period of 30 days. AF recurrence was defined as any electrocardiographically documented episode lasting more than 30 seconds.

Results

A total of 13 patients were included in the study. The mean age was 72.6 ± 4.8 years, and all patients were male. Three patients (23.1%) underwent an index "redo" ablation. Seven patients (53.8%) had paroxysmal atrial fibrillation (AF). The median CHA2DS2-VASc score was 3 [2, 4.5], with a mean ejection fraction of 50.4 ± 14.8% and a mean left atrial volume index of 47.6 ± 15.7 mL/m². Eleven patients underwent PFA with the pentaspline Farawave catheter, and two with the focal Sphere-9 catheter. Additional extra-pulmonary vein lesions were performed in 11 patients, including posterior wall ablation in ten patients, cavotricuspid isthmus ablation in five, and mitral isthmus ablation in four patients.

The primary endpoint occurred in one patient (7.7%) who developed acute respiratory failure complicated by pulseless electrical activity (PEA) arrest. The patient was successfully resuscitated but required prolonged hospital admission. All patients achieved acute pulmonary vein isolation, and six-month atrial fibrillation-free survival was 54.4%.

Conclusion

In this multicentre experience, pulsed field ablation (PFA) in patients with cardiac amyloidosis was feasible and acutely safe; however, the mid-term efficacy was suboptimal, with a relatively low six-month arrhythmia-free survival despite complete acute pulmonary vein isolation. These findings suggest that the current PFA strategies may not provide durable rhythm control in this population, underscoring the need for tailored ablation approaches and further research to improve long-term outcomes in patients with cardiac amyloidosis and atrial fibrillation.Figure 1