Atrial Flutter in Partially Anomalous Pulmonary Venous Return: Electrophysiological Insights in Holt-Oram Syndrome.

Partially anomalous pulmonary vein return (PAPVR) is a heterogeneous group of congenital heart defects. Here, we describe a 51-year-old patient with corrected PAPVR (cPAPVR) and atrioventricular canal defect who presented for AFL ablation. The right pulmonary veins were isolated, and the OP was heterogeneously fibrotic. Three left AFL and one cavo-tricuspid isthmus (CTI)-dependent AFL were induced and mapped using activation and Ablation at each site terminated the AFL. Subsequently, the entire OP was isolated. Post-ablation, she had no atrial arrhythmia at 6 months follow up. Genetic testing identified a pathological mutation in the TBX5 gene, consistent with Holt-Oram syndrome.