Metoprolol in Patients With HFrEF and COPD

The goal of the clinical trial was to see if Metoprolol was effective in treating patients with heart failure and chronic obstructive pulmonary disease. It will also learn about the safety of Metoprolol. The main questions it aims to answer are: Did Metoprolol reduce the frequency of all-cause deaths and re-hospitalizations in subjects? What medical problems do participants experience after taking Metoprolol? The researchers will compare different doses of Metoprolol to see the best dose for Metoprolol. Participants will: Take Metoprolol 23.75mg/ day or the maximum tolerable dose of Metoprolol daily for 24 months. Regular outpatient follow-up visits to the research center. Their symptoms and Metoprolol dosage were recorded.