Sinus node dysfunction in pediatric and young adult patients: treatment by implantation of a permanent pacemaker in 39 cases.

To examine the clinical course of sinus node dysfunction that necessitates permanent pacing in the pediatric and young adult populations, we studied the records of the 39 patients 40 years of age or younger (mean age, 23 years) who underwent implantation of a permanent pacemaker for treatment of this disorder at our medical center between 1960 and 1983. The tachycardia-bradycardia syndrome was the most common rhythm disturbance, and syncope was the most frequent initial symptom. All symptomatic patients noted resolution of symptoms after pacemaker implantation. Twenty-five of the 39 patients (64%) had associated cardiovascular disease, most commonly transposition of the great arteries. In each of the 11 patients with this anomaly, sinus node dysfunction developed after a surgical procedure for correction of the defect. Of the total patient population, 20 patients (51%) had previously undergone a cardiac operation. The mean interval between pacemaker implantation and the previous operation was 105 months. After a mean follow-up of 50.5 months, the patients with no obvious underlying heart disease have done well. Each of the eight patients who have died had underlying cardiovascular disease. None of the deaths was thought to be pacemaker related. Sinus node dysfunction should be considered in the differential diagnosis of young patients with syncope or dizziness, especially if they have undergone a reparative cardiac surgical procedure. If symptomatic sinus node dysfunction is confirmed, permanent pacing is an effective therapeutic modality. In the absence of associated heart disease, the prognosis seems to be excellent.