Catheter ablation for supraventricular arrhythmias in adults with congenital heart disease: Recurrence rates and predictors of acute procedural success

Aims: To define the cohort of adult congenital heart disease (ACHD) patients undergoing catheter ablation for supraventricular arrhythmia in a large tertiary centre, characterise outcomes, and determine factors associated with arrhythmia recurrence.Methods: Single centre retrospective study of all catheter ablations for atrial arrhythmias in ACHD patients between September 2014 and October 2021. Patients were identified using a field search through a centralised database. Pre-specified clinical and procedural data of interest, and time from ablation to recurrence, were determined. Cox regression analyses were used to determine potential predictors of acute procedural success and arrhythmia recurrence.Results: Cardiac ablation for supraventricular arrhythmia was undertaken in 142 cases across 100 unique patients (median age 41, interquartile range 31-52), with 70 (49%) cases treated for macro-reentrant atrial tachycardia, 16 (11%) for focal atrial tachycardia, 19 (13%) for multifocal atrial tachycardia, 17 (12%) for atrial fibrillation, 7 (5%) for atrioventricular nodal reentrant tachycardia, and 8 (6%) for atrioventricular reentrant tachycardia; and 68 cases (48%) had recurrent arrhythmia with a median time to recurrence of 800 days. Multivariable analysis identified acute procedural success as an independent predictor of freedom from arrhythmia, and ablation for persistent atrial fibrillation as an independent predictor for recurrence of arrhythmia.Conclusion: Catheter ablation for supraventricular arrhythmia in ACHD patients is safe and effective, with most patients achieving multiple arrhythmia-free months. Procedural success and arrhythmia mechanism are important predictors of recurrence.