Distribution Variance of Focal Atrial Tachycardia Foci and Long-Term Outcomes After Ablation: Experience From Two Chinese Centers.

Introduction: The distribution of the origin of focal atrial tachycardia (FAT) in patients with different ages have not been clearly elucidated. We aimed to evaluate age differences in foci and factors influencing recurrence after radiofrequency catheter ablation in adult and juvenile patients with FAT.

Methods and results: A total of 323 consecutive FAT patients who underwent electrophysiological study and radiofrequency catheter ablation between January 2011 and March 2023 were selected for this study. We divided the patients into three groups according to the age of FAT onset: juvenile (< 18 years), young adult (≥ 18 and < 45 years), and middle-aged and old adult (≥ 45 years). Juvenile had a higher proportion of FAT originating from the left atrial appendage, the right atrial appendage, and the free or posterior wall of the right atrium. FAT in middle-aged and old adult patients was more likely to originate from the crista terminalis, tricuspid annulus, non-coronary cusp, and para-His. Young adults had a higher proportion of FAT originating from the superior vena cava and pulmonary veins. After a mean follow-up of 47.2 months, FAT recurred in 57 patients. Multivariate Cox regression analysis suggested that multifocal ablation (HR: 3.055, 95% CI: 1.476-6.323) and NT-proBNP (per standard deviation, HR: 1.367, 95% CI: 1.157-1.614) were independently associated with arrhythmia recurrence after ablation.

Conclusion: Significant age differences were observed in the distribution of FAT foci. Multifocal AT and elevated NT-proBNP independently predicted FAT recurrence after ablation.