Pathophysiology and Management of Arrhythmias Associated with Atrial Septal Defect and Patent Foramen Ovale.

Atrial septal defects (ASDs) are among the most common of congenital heart defects and are frequently associated with atrial arrhythmias. Atrial and ventricular geometrical remodelling secondary to the intracardiac shunt promotes evolution of the electrical substrate, predisposing the patient to atrial fibrillation and other arrhythmias. Closure of an ASD reduces the immediate and long-term prevalence of atrial arrhythmias, but the evidence suggests that patients remain at an increased long-term risk in comparison with the normal population. The closure technique itself and its timing impacts future arrhythmia risk profile while subsequent transseptal access following surgical or device closure is complicated. Newer techniques combined with increased experience will help to alleviate some of the difficulties associated with optimal management of arrhythmias in these patients.