2.1. Patients
This study was approved by the Research Ethics Committee of the National Institute of Cardiology under protocol number 03218512.0.2005.5272. Written informed consent was obtained from all subjects/patients. This was a single-blind, randomized, placebo-controlled clinical trial. Patients with a clinical diagnosis of HF, who had been referred for cardiac rehabilitation by their attending physicians and were awaiting scheduling, were assessed. Inclusion criteria were age ≥50 years, HF class I or II NYHA, clinical stability (symptoms and medications) for at least 4 weeks before inclusion, and left ventricular ejection fraction (LVEF) ≤ 50% (echocardiographically defined). Exclusion criteria were creatinine clearance <50 mL/min/1.73 m