RESUMO
BACKGROUND: Exercise capacity is critical for therapy and prognosis in patients with heart failure (HF). Effect of beta-blockers (BB) on exercise capacity in elderly patients with HF remains unclear. OBJECTIVES: To assess contribution of BB to functional capacity and left ventricular (LV) function in the elderly with HF. DESIGN: According to the protocol of CIBIS-ELD study group, elderly patients were treated with BB during 12 weeks. In CPET subgroup, an integral part of the CIBIS ELD study group, patients were performed Doppler echocardiography and cardiopulmonary exercise testing (CPET) before BB therapy and after 12 weeks. SETTING: Randomized patients with HF beta blockers naïve. PARTICIPANTS: thirty patients with HF aged over 65 years were included in CPET subgroup, while 847 were incorporated in CIBIS ELD study group. RESULTS: Heart rate (HR) and systolic blood pressure (SBP) after BB significantly decreased at rest (p<0.001) and during exercise (p<0.05), with sustained level of peak VO2. Observed changes of resting HR and peak HR were closely correlated (p<0.001). Significant improvement of LV ejection fraction after BB was obtained (p=0.003) and symptoms of breathlessness were reduced (p=0.001). Left ventricular diastolic dysfunction at rest significantly contributed to exercise capacity (p=0.019). CONCLUSIONS: Beta-blockers in elderly patients with HF are related to a significant decrease of HR and SBP, improvement of systolic LV function and sustained exercise tolerance. Resting LV diastolic dysfunction is strongly associated with lower exercise capacity.