Focal Pulsed Field Ablation for Atrial Arrhythmias: Efficacy and Safety under Deep Sedation

Abstract

Focal pulsed field ablation (PFA) is a novel technique for treating cardiac arrhythmias. It has demonstrated positive results in initial studies and has a good safety profile. In recent studies, PFA was often utilized for first-time pulmonary vein isolation (PVI) and was performed under general anesthesia. In our study, we assessed the feasibility, safety, acute procedural efficacy, and efficiency of focal PFA under deep sedation in patients, 80% of whom had undergone at least one left atrial ablation previously. We treated 30 patients (71 ± 7, 46% male) using the CENTAURI system for various atrial arrhythmias, including atrial fibrillation, typical and atypical atrial flutter, and focal atrial tachycardia. The average procedure and fluoroscopy times were 122 ± 43 min and 9 ± 7 min, respectively. A total of 83.33% of patients received additional line ablations beyond PVI, specifically targeting the posterior box and anterior mitral line. All ablations were successfully performed in deep sedation with only one major and one minor complication observed. The major complication was a vasospasm of the right coronary artery during ablation of the cavotricuspid isthmus, which was treated successfully with intracoronary nitroglycerin. All patients could be discharged in sinus rhythm. Moreover, adenosine appears effective in identifying dormant conduction in some patients after focal PFA. In conclusion, focal PFA is an effective approach for complex left atrial ablations under deep sedation, offering both high efficacy and efficiency with a reliable safety profile. Studies on long-term outcomes are needed.

Keywords: CENTAURI; adenosine testing; atrial fibrillation; atypical flutter; coronary vasospasm; repeat ablation.

Figure 1

Example of left atrial posterior wall isolation and lateral mitral isthmus ablation in a patient with two prior PVIs and durably isolated pulmonary veins. Panel (A) displays the bipolar voltage map pre-ablation, while Panel (B) illustrates the post-ablation voltage map. Red tags denote the PFA application sites. Voltage maps are color-coded: purple represents local electrograms > 0.5 mV, and red indicates local electrograms < 0.05 mV.

Figure 2

The coronary angiogram depicts a vasospasm of the right coronary artery (arrows) during PFA of the cavotricuspid isthmus. Panel (A) shows the coronary angiogram 9 min after the onset of symptoms, followed by Panel (B) at 17 min and Panel (C) at 18 min, and by the time of Panel (D) at 24 min, the vasospasm had nearly completely resolved and symptoms had subsided. During this period, a cumulative dose of 1 mg nitroglycerin was fractionally administered into the right coronary artery.