We report the case of an asymptomatic six-year-old child with left atrial isomerism and sinus venosus atrial septal defect. The physical examination revealed several periods of bradycardia. During a 24-hour electrocardiographic monitoring the patient presented a significant sinus node dysfunction with sinus pauses of up to 2.4 seconds. A permanent pacemaker was implanted, with a satisfactory outcome.
Congenital heart defects; left atrial isomerism; sinus node dysfunction