Comparative Effectiveness Research to Assess the Use of Primary ProphylacTic Implantable Cardioverter Defibrillators in Europe

Inclusion Criteria: * Ischemic or dilated cardiomyopathy and recommendation for primary prophylactic ICD treatment following current international treatment guidelines * Written informed consent * If ICD implantation is planned, enrollment and study baseline testing needs to be completed before de-novo ICD implantation Exclusion Criteria: * Permanent atrial fibrillation or atrial fibrillation at baseline in case more than 15% of such patients at a given time have been enrolled * Indication for secondary prophylactic ICD treatment * Indication or candidate for cardiac resynchronization therapy * AV block II°-III° at resting heart rates * Implanted pacemaker * Unstable cardiac disease such as decompensated heart failure (NYHA functional class IV) or acute coronary syndrome * Participation in other clinical trials which exclude enrolment in other trials