In 39 patients (mean age, 66 years) treated for sick sinus syndrome (SSS) with pacemaker insertion, the long-term prognosis was studied. Fifteen patients (42%) died during the follow-up period of 6 to 59 months (mean, 25 months). Three patients were unavailable for follow-up. Eleven of the 15 deaths (73%) were cardiac-related, yet none could be associated with either an arrhythmia or pacemaker failure. Symptoms recurred or persisted after pacemaker insertion in 14 patients (mean age, 71 years), nine of whom died (31 deaths per 100 patient follow-up years). Twenty-two patients (mean age, 63 years) were asymptomatic after pacer insertion, six of whom died (11 deaths per 100 patient follow-up years). These follow-up results demonstrate a poor long-term prognosis in patients with SSS and persistent symptoms following permanent pacing.
(Arch Intern Med 136:406-408, 1976)