Association between pulmonary vein orientation and ablation outcome in patients undergoing multi-electrode ablation for atrial fibrillation

• In multi-electrode AF ablation, cranial left upper pulmonary vein orientation was associated with ablation outcome.
• In multi-electrode AF ablation, caudal left lower pulmonary vein orientation was associated with ablation outcome.
• In multi-electrode AF ablation, right upper and lower pulmonary vein orientation were not associated with ablation outcome.
• Pulmonary vein orientation may be useful to select the most suitable patients for multi-electrode AF ablation.

BackgroundPrevious studies reported on the impact of pulmonary vein orientation on pulmonary vein isolation (PVI) outcome in atrial fibrillation patients undergoing laser balloon PVI and point-by-point radiofrequency ablation.ObjectiveDemonstrate the association between pulmonary vein orientation and PVI outcome after multi-electrode radiofrequency ablation.Methods120 patients undergoing PVI with a circular MER catheter were included. A left atrial ECG-triggered CT was performed in all patients prior to PVI. The orientation of all pulmonary veins at the insertion into the left atrium was measured in the axial and coronal planes. pulmonary veins were classified as having a ventral/dorsal and caudal/cranial orientation depending on the pulmonary vein trunk angle as compared to the median angle.ResultsMean age was 56 years, arrhythmia-free survival after a median follow-up of 20 months was 54.2%. Left upper pulmonary vein orientation within the coronal plane was associated with arrhythmia-free survival, ranging from 58% with a cranial pulmonary vein orientation to 21% with a caudal orientation (p = 0.003). Similarly, arrhythmia-free survival was 50% in patients with a caudal orientation and 33% in patients with a cranial orientation of the left lower pulmonary vein in the coronal plane (p = 0.036). Pulmonary vein orientation in the axial plane and orientation of the right-sided pulmonary veins were not associated with arrhythmia-free survival. Multivariable analysis showed an independent association between both left upper (hazard ratio 2.8, p = 0.001) and left lower (hazard ratio 0.490, p = 0.034) pulmonary vein orientation and arrhythmia-free survival.ConclusionIn MER ablation, orientation of the left upper and caudalpulmonary veins in the coronal plane were independently associated with arrhythmia-free survival after multi-electrode PVI.