Atrial fibrillation in adults with congenital heart disease

A convergence of epidemiological and clinical features has prompted a precipitous rise in the prevalence of atrial fibrillation (AF) in the expanding population of adults with congenital heart disease. Herein, we synthesize the current state of knowledge on epidemiological features, associated morbidities, and pathophysiological insights regarding AF in adults with congenital heart disease. Management issues are examined including surgical, pharmacological, and catheter-based therapies. Throughout, knowledge gaps and avenues for future research are identified. Although AF has been coined the next arrhythmic epidemic to strike adults with congenital heart disease, it has already usurped atrial macroreentrant tachycardia as the most common presenting arrhythmia over the age of 50 years. Much remains to be discovered about the mitigating role of types of congenital defects, residual hemodynamic lesions, surgical sequelae, and ramifications of shunts and cyanosis on mechanisms and determinants of AF. Thromboprophylaxis is the cornerstone of pharmacological management, with anticoagulation recommended in patients with moderate or complex congenital heart disease and those with significant valve disease or risk factors for stroke. Considering the limited success with antiarrhythmic drugs, catheter ablation is increasingly performed. Non-pulmonary vein sources, focal and reentrant arrhythmias, appear to be important triggers for AF in this population. As such, they should be identified and addressed during catheter ablation interventions. The nascent literature on electrical isolation of pulmonary veins suggests that it is feasible and safe, although initial success rates appear to be modest. A more thorough understanding of underlying mechanisms and substrates carries the potential to further improve outcomes.