In the past it has been shown that the implantable cardioverter-defibrillator (ICD) is an ideal approach to prevent sudden cardiac death. Since the first human implant in 1980, more than 70.000 patients with life-threatening ventricular tachyarrhythmias have been treated with the ICD. Today, more and more patients are undergoing ICD implantation and further indication will expand this therapy. However, due to an increased number of patients with ICD therapy, patient management and the control of patient and device related data will become difficult. To improve patient management the DEFICARD concept was introduced in clinical cardiology in 1993. This concept consists of a data base on a personal computer and a multifunctional chip card which the patient carries around with him. We have followed in our phase-1 study 102 patients, mean age 57±11 years, after ICD implantation with the DEFICARD. Patients attended the outpatient clinic at two months intervals. The acceptance of the DEFICARD by our patients was extremely high (98%). With the DEFICARD the length of each outpatient clinic visit was shorter (23±12 min) compared to the conventional way (45±20 min) (p<0.05). All data were stored and reevaluated on the card and, therefore, up-to-date information was always available about the ICD and the state of health of the patients. In our phase-2 protocol, we will invite three additional hospitals to participate in the DEFICARD project. During this period, we will study the co-operation in patient management between our institution as principal investigator and other physicians. We conclude that the DEFICARD is suitable in all patients and will improve patient management after ICD implantation. It will reduce the time needed in the outpatient clinic and reduce costs when treating patients with automatic implantable cardioverter-defibrillators.