Closure of Secundum Atrial Septal Defect and Risk of Incident and Recurrent Arrhythmia

BACKGROUND: Atrial septal defect (ASD) is a simple defect but carries considerable morbidity, especially arrhythmias.

OBJECTIVES: Data on the impact and timing of ASD closure and the risk of (recurrent) arrhythmia remain scarce and will be the focus of this study.

METHODS: This Danish nationwide cohort study included all patients diagnosed with secundum ASD (1977-2024), followed until arrhythmia, death, emigration, or study end (Jan 2024). The risk of (recurrent) arrhythmias was assessed based on ASD closure status and closure technique.

RESULTS: Among 6,469 patients with ASD (43.3% men), 34.6% underwent ASD closure (65.5% surgically and 34.5% percutaneously). The incidence rate of arrhythmia was 13.3 (95%CI 12.6-14.2) per 1,000 PY, with atrial fibrillation/flutter being the most prevalent. Older age at diagnosis and closure were linked to higher incidence and recurrence of arrhythmia. In time-dependent Cox regression analyses, surgical ASD closure was associated with an increased risk of arrhythmias compared to no closure (adjusted HR 1.38 [95%CI 1.19-1.60]), whereas no difference was found for percutaneous closure. Overall, three in four patients experienced arrhythmia recurrence. ASD closure was associated with a decreased risk of recurrence, yet statistical significance was observed only when comparing percutaneous closure to no closure (adjusted HR 0.79 [95%CI 0.64-0.98]).

CONCLUSIONS: The incidence rate of arrhythmia among patients with ASD was 13 per 1,000 PY, with age and closure technique being pivotal factors. Surgical closure was associated with an increased risk of arrhythmias compared to no closure, while percutaneous closure was associated with a decreased risk of recurrence.