Invasive revascularization improves prognosis, functional status and quality of life in patients with severe angina pectoris and impaired left ventricular function, and treatment with ACE-I reduces the development of cardiac events and left ventricular dysfunction in patients without or with mild angina pectoris. However, the effects of a combined treatment strategy with invasive revascularization and subsequent long-term ACE-I therapy in patients with limiting angina pectoris and impaired left ventricular function have not previously been investigated. APRES is a long-term, prospective, randomized double-blind study that evaluates the effects of ramipril 10 mg o.d. on the long-term development of cardiac events, left ventricular function, functional status and quality of life following invasive revascularization in patients without recent AMI or clinical heart failure and with preoperative ejection fraction in the range 0.30-0.50. The rationale, design and power of APRES and the choice and relevance of outcome measures are discussed. Based on experience and results from the first year of the study for screening procedure, inclusion rate, patient compliance, reproducibility analyses and the magnitude of outcome measures, we conclude that the study is feasible and safe. The included patients match with the target population, the outcome measures seem appropriate and the power considerations valid for the majority of the outcome measures.