Feasibility and efficacy of a circular over-the-wire pulse field ablation catheter for linear ablation lesions
J Gill, V Sagar, Z Akhtar, Z Zuberi, A Bajpai, L Leung, M M GallagherAbstract
Background
Pulse field ablation (PFA) uses ultrashort electrical impulses to cause myocardial electroporation that is typically used to treat the pulmonary veins in the treatment of atrial fibrillation (AF).
Purpose
The safety and efficacy of PFA for linear lesions is less well substantiated in the literature. We describe a novel use of a circular, over-the-wire PFA catheter for the ablation of the cavotricuspid isthmus (CTI), mitral isthmus (MI), and posterior wall isolation (PWI) as part of ablation for AF.
Methods
Data was collected prospectively on consecutive patients undergoing AF ablation using the a circular over-the-wire catheter. CTI, MI, and PWI ablation was performed as per operator discretion. Acute bidirectional block was tested for both the CTI and MI, and isolation of the posterior wall was demonstrating exit block and remapping. Continuous periprocedural ECG monitoring was performed. Patients underwent usual clinical follow-up.
Results and Discussion
62 patients underwent ablation for atrial fibrillation. 52 patients had CTI ablation and 36 had MI ablation. Acute success rate (bidirectional block across the CTI) was observed in 98% of cases; in one patient, testing was impossible due to a recurrent left atrial arrhythmia. MI block was achieved in 94.4% of patients. In one case, the tip of the ablation catheter was transiently caught within the tricuspid apparatus during CTI ablation but was freed without complication. The only major complication was periprocedural Takotsubo cardiomyopathy and the patient made a full recovery. Mean follow-up was 6.4 Months. Recurrence of AT/AF was observed in 14.5% patients during the follow-up period.
Conclusions
PFA using a circular over-the-wire catheter is effective for CTI, MI, and PWI ablation. Acute success rates for the CTI ablation are comparable to radiofrequency ablation. MI Ablation shows significantly increased success rates when compared to RFA. No clinically significant vasospasm was identified in this cohort despite a total of 857 lesions in close proximity to coronary arteries. Caution should be exercised when using the catheter close to valve apparatus due to the possibility of interaction between the two.Flouroscopy of CTI Abaltion technique