PO-04-123 TACHYARRHYTHMIA OUTCOMES IN CONGENITALLY CORRECTED TRANSPOSITION OF THE GREAT ARTERIES: DOES TREATMENT PATHWAY MATTER?

Abstract

Patients with congenitally corrected transposition of the greater arteries (cc-TGA) are at risk for developing both atrial and ventricular tachyarrhythmia. However, data on the impact of treatment pathway (non-surgical management, anatomic repair, or physiologic repair) is limited. To describe arrhythmia types and freedom from early (≤30 days post-op) and late (>30 days post-op) sustained tachyarrhythmia requiring intervention (medication, cardioversion, or ablation) in patients with cc-TGA based on treatment pathway. We conducted a retrospective cohort study including all patients with cc-TGA who were followed at our institution between January 1995 and December 2021. Patients were stratified according to treatment pathway as follows: non-surgical, anatomic repair, and physiologic repair. Tachyarrhythmia types analyzed included sustained atrial fibrillation (AF), atrial flutter (AFL), atrial tachycardia and ventricular tachycardia. A total of 170 patients were included in the study, of whom 82 underwent anatomic repair (median age 1.5 yrs, median follow-up 11.5 yrs), 46 physiologic repair (median age 25.2 yrs, median follow-up 12.6 yrs), and 42 non-surgical (median age 35.7 yrs, median follow-up 11 yrs). Overall 50 patients (29%) had tachyarrhythmia: 12/82 (15%) anatomic repair, 15/46 (33%) physiologic repair, and 23/42 (55%) non-surgical. Prevalence of AFL was highest after anatomic repair compared to physiologic repair or non-surgical (32% vs. 22% vs 0%, p=0.024). Prevalence of AF was higher in physiologic repair and non-surgical compared to anatomic repair (52% vs. 65% vs. 0%, p<0.0001). Patients with physiologic repair had more late tachyarrhythmia versus anatomic repair (83% vs. 33%, p=0.002). Freedom from tachyarrhythmia was lowest in anatomic repair vs. physiologic repair and non-surgical (p=0.013), Figure 1A. Estimated freedom from tachyarrhythmia at 20 years in the anatomic, physiologic, and non-surgical groups were 80%, 88%, and 95%, respectively. Freedom from postsurgical tachyarrhythmia trended towards increase prevalence after physiologic repair compared to anatomic repair (p=0.065), Figure 1B. Arrhythmia type differed based on treatment pathway, with AFL more prevalent after anatomic repair and AF more prevalent in physiologic repair and non-surgical management. Freedom from tachyarrhythmia was lowest in the anatomic repair group. Continued follow-up after anatomic repair is needed to determine their long-term risk beyond the 2nd decade.