Effect of Pulsed-Field Ablation on Human Coronary Arteries

Background Pulsed-field ablation (PFA) is known to cause acute coronary spasm. Whether this translates into long-term coronary artery stenosis is unknown. Objectives This study sought to evaluate changes in coronary artery after PFA for atrial flutter. Methods After pulmonary vein isolation with PFA (Farapulse; Boston Scientific), patients undergoing ablation of the mitral isthmus (MI) or cavotricuspid isthmus (CTI) were included. They underwent coronary angiography and optical coherence tomography (OCT) before and immediately after ablation. Bolus intracoronary nitroglycerine was given before and throughout ablation. Three months after ablation, patients underwent repeated OCT. Results A total of 21 patients were included. 1 patient did not undergo PFA owing to the incidental finding of a critical coronary lesion in close proximity to the area to be ablated. Another patient defaulted postprocedure imaging follow-up. 19 patients had paired imaging data, in 20 coronary vessels (18 right coronary and 2 left circumflex arteries). At the ablation site, at 3 months, vascular wall area increased by a median of 0.40 mm (Q1-Q3: 0.13-0.71 mm ; P < 0.01), or 17.1% (Q1-Q3: 8.6%-31.0%). The median reduction in the luminal area was 0.70 mm (Q1-Q3: 0.18-1.30 mm ; P < 0.01), or 10.1% (Q1-Q3: 4.7%-16.2%). These changes were not observed in a predetermined reference site remote from the ablation target. Conclusions PFA of the CTI and MI is associated with acute spasm, and mild narrowing of the coronary arteries at 3 months. Although intracoronary vasodilator therapy may prevent or treat acute spasm, the risk of arterial stenosis remains, calling for heightened vigilance and long-term follow-up.