[Atrioventricular block in Kearns-Sayre syndrome]

We report a case of a 17-year-old woman with Kearns-Sayre Syndrome who developed a high degree atrioventricular block. She had intraventricular conduction disturbances with normal atrioventricular conduction in previous electrocardiograms. The diagnosis criteria of this rare syndrome are commented on, and we describe the electrophysiological features, prognostic and treatment that atrioventricular conduction disturbances produce in these patients. We emphasize the necessary collaboration between neurologists and cardiologists in the early recognition of the conduction disturbances for implanting a prophylactic pacemaker.