Late-Onset Perinodal Atrial Tachycardia After Transcatheter Atrial Septal Device Closure.

backgroundAtrial septal defect (ASD) device closure generally provides excellent long-term outcomes; nevertheless, atrial arrhythmias such as atrial fibrillation and macro-reentrant atrial tachycardias may still appear years later. Although these are well-recognized late sequelae, focal atrial tachycardia (FAT), particularly from the perinodal region after ASD device closure, is exceptionally uncommon. CASE SUMMARY: A 44-year-old woman presented 10 years after percutaneous ASD closure with recurrent palpitations. Electrocardiography demonstrated a narrow-complex regular tachycardia. Electrophysiology study revealed an adenosine-sensitive FAT arising from the perinodal region near the triangle of Koch. Because ablation from the right atrial septum carried a substantial risk of complete heart block, an alternative strategy was pursued. Mapping identified the earliest activation in the noncoronary cusp, where radiofrequency ablation successfully and safely terminated the arrhythmia. DISCUSSION: Although complete heart block and macro-reentrant tachycardias are recognized after ASD closure, FAT a decade later is exceedingly rare and, to our knowledge, previously unreported. TAKE-HOME MESSAGE: FAT can occur long after ASD closure, and noncoronary cusp ablation offers a safe option for perinodal foci.