Pulsed field ablation for paroxysmal atrial fibrillation is safe for the brain

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background While symptomatic thromboembolic events are rare, silent cerebral emboli (SCL) or events (SCE) are a common observation after LA ablation for AF, using thermal ablation techniques. Pulsed field ablation (PFA) is a novel, non-thermal ablation modality that is able to ablate myocardial tissue with minimal e!ect on surrounding tissue. Preclinical data show absence of cerebral emboli after extensive PFA ablation. However, clinical data on SCL/SCE after PFA are rare. Objective We investigated neurological deficits and/or SCL/SCE after PFA in paroxysmal AF using National Institutes of Health Stroke Scale (NIHSS) scores to quantify cerebral impairment and cerebral MRI. Methods LA appendage thrombus exclusion was done by CT-angiography. PVI using PFA was performed with interrupted oral anticoagulation at the day of the procedure and heparin administered before single transseptal puncture (target ACT >325 sec.). In all procedures, extensive high-density pre- and post-ablation 3D bipolar voltage maps were performed to document PVI. NIHSS scores were assessed at baseline, days 2 and 30 after PVI. One day after PVI, a cerebral 1.5 Tesla MRI using di!usion-weighted imaging (DWI) and FLAIR sequences to document occurrence of SCL/SCE was performed. Results In 30 patients (age 63 years; 47% male; CHA2DS2-VASc-Score 2), uncomplicated PFA was performed, with all PVs acutely isolated. Skin-to-skin procedure time was 120 min and LA dwell time was 109 min. In-hospital and 30-day clinical follow-up was uneventful. No patient showed neurological deficits. All NIHSS scores at all stadiums were the minimum value of 0. Cerebral MRI scans were normal in 29/30 (97%) patients. In 1/30 (3%) patient, a single 7-mm cerebellar lesion was observed. Forty days after the procedure, a follow-upMRI scan showed complete regression of the lesion. This origin of this single lesion could not be established. Air embolization after multiple catheter exchanges, or embolization of tissue debris after transseptal puncture cannot be ruled out. Conclusion PVI using PFA in patients with paroxysmal AF causes no neurological deficits and shows absence of SCL/SCE in 97% of patients. In one patient, a single small SCL/SCE of unknown origin occurred with complete regression after 40 days. PFA seems to be a safe ablation modality for the brain.