Cardiac arrhythmias are being depressed with increased frequency in the pediatric population. Causes of pediatric arrhythmias in the general population include severe metabolic or electrolyte disturbances, drug toxicity, and chest trauma. Repairs of complex congenital heart disease have frequently left this population with persistent or recurrent postoperative arrhythmias. The diagnosis, evaluation, and management of pediatric arrhythmias requires nurses to be skilled in hemodynamic assessment and arrhythmia detection. The registered nurse's grasp of developmental issues and family education is vital in providing quality care to families dealing with these diagnoses.