Implantation of automatic cardioverter-defibrillators via median sternotomy

15 AICD (automatic implantable cardioverter-defibrillator) Model B units were implanted in 10 patients. The median sternotomy is our preferred surgical approach using a right atrial patch electrode, a left ventricular apex patch electrode, and two closely placed epicardial sensing electrodes. Follow-up is 109 patient months and all patients are alive. AICD units discharged for ventricular tachycardia, ventricular flutter, and ventricular fibrillation. Discharges also occurred for sinus tachycardia and atrial fibrillation above the rate limit in three units. Premature pulse generator depletion has occurred in four AICD-B units 3 to 18 months postimplant and appears due to a defect in original battery design. Discharge of the AICD for supraventricular tachycardia is a problem that will remain until a better means of differentiating supraventricular tachycardia from ventricular tachyarrhythmias is found. The AICD appears to prevent sudden death from ventricular tachyarrhythmias.