Patients with ischemic or dilated cardiomyopathy and "standard indications" for ICD treatment. "Stamdard indications" are approved and strictly follow current guidelines, the decision on ICD implantation is based on left-ventricular ejection fraction or the history of malignant arrhythmia. i.e. secondary prevention of sudden cardiac death). Implantation procedure is performed at University Medical Center Goettingen.