Patients with history of mitochondrial disorders are at increased risk of having conduction disorders and cardiomyopathy and should have low threshold for pacemaker and implantable cardioverter defibrillator placement. Kearns Sayre syndrome is the result of deletions in mitochondrial DNA which causes bilateral pigmentary retinopathy and conduction abnormalities. Judicious use of implantable cardioverter defibrillator in this subset population with cardiomyopathy or prolonged QT interval is required in addition to pacing to prevent risk of sudden cardiac death. A subset of these patients might continue to experience life threatening arrhythmias including torsade de pointes and ventricular fibrillation despite a functional pacemaker.