OBJECTIVES: About 190,000 Germans suffer a myocardial infarction (MI) each year. Of these, 25% may be eligible for an implantable cardioverter defibrillator (ICD) due to low left ventricular ejection fraction. Given the high costs of implantation, the purpose of this study was to assess the cost-effectiveness of ICDs compared to conventional therapy in patients with an ejection fraction ≤ 30% after MI in Germany.  METHODS: The economic evaluation was performed from the perspective of the German statutory health insurance (SHI). In order to simulate costs and effectiveness over lifetime, a Markov model was constructed with 7 health states. The model was based on 8-year follow-up data for ICD implantation after MI (MADIT II), which were published recently. RESULTS: The analysis shows that ICD implantation compared to conventional therapy in patients fulfilling MADIT-II criteria has a cost-effectiveness ratio of €44 736 per quality-adjusted life year gained. If every patient insured by the SHI and fulfilling the MADIT-II criteria would receive an ICD, the model suggests expenditures between €173 million and €1.7 billion per year. CONCLUSIONS: ICD therapy cannot be considered clearly cost-effective when compared to many well-accepted interventions. If policy makers decide to reimburse ICDs in the MADIT-II population, they will need to either raise premiums or abandon coverage for other currently funded medical interventions.