An 81-year-old female with the sick sinus syndrome had a permanent pacemaker implanted. She subsequently developed ventricular fibrillation and was successfully defibrillated. However, the defibrillation paddle was placed on the pulse generator which led to a complete loss of function of the pulse generator. External defibrillation can produce varying degrees of damage to the implanted pulse generator. The resultant abnormalities are discussed and recommended defibrillation procedures are also outlined in this report.