Clinical significance of persistent iatrogenic atrial septal defect after catheter ablation for atrial fibrillation.

BACKGROUND

Iatrogenic atrial septal defect (iASD) is a frequent complication of catheter ablation (CA) for atrial fibrillation (AF); however, its clinical significance remains unclear.

OBJECTIVE

This study investigated the association of persistent iASD with AF recurrence and major clinical outcomes after AF ablation in an overall cohort and a predefined subgroup.

METHODS

This retrospective study included 1288 consecutive patients who underwent first-time CA for AF at Ogaki Municipal Hospital from 2012 to 2022, with transthoracic echocardiography performed before and 3 months after ablation. A predefined subgroup of 578 patients who underwent contact force-sensing radiofrequency ablation using a standardized two-sheath approach with an ablation catheter and a circular mapping catheter was also evaluated. Study outcomes included AF recurrence, all-cause mortality, cardiovascular mortality, heart failure (HF) hospitalization, and ischemic stroke.

RESULTS

iASD was detected in 127 patients (9.9%). In both the overall cohort and the predefined subgroup, patients with iASD had higher AF recurrence on unadjusted analysis (P = .002 and P = .004, respectively), but not after multivariable adjustment. Multivariable analysis identified sheath size and number, body size-related factors, and tricuspid regurgitation peak velocity as independent predictors of persistent iASD. Cardiovascular mortality and HF hospitalization were higher in patients with persistent iASD (P = .02 and P < .001, respectively), with HF events clustering in the early phase (≤6 months), but not ischemic stroke (P = .28).

CONCLUSION

Persistent iASD was associated with AF recurrence on unadjusted analysis, cardiovascular mortality, and early-phase HF hospitalization after AF ablation. These findings suggest that persistent iASD may serve as a clinically relevant marker of adverse prognosis after AF ablation.