A Comparison of the Effect of Carvedilol and Metoprolol on Airways Tone in Patients With Heart Failure

Overview

This study looks at the effect of two drugs (carvedilol and metoprolol) which are used for patients with CHF (chronic heart failure). These agents are beta-blockers and, although effective in heart failure, may cause increases in airways tone and thus limit air getting into the lower parts of the lungs. Carvedilol is more active at blocking the receptor that opens up the airways and therefore theoretically may be more likely to reduce airways tone than metoprolol, although this has never been studied in patients with heart failure, and that is the purpose of the present study. We are looking to enrol 45 patients with heart failure and mild obstruction to the flow of air in their lungs. Patients will be randomised to either carvedilol or metoprolol (standard doses). Following a minimum of 2 weeks of therapy of study medication the patient will undergo a study day involving an assessment of their lung function, an assessment of their heart failure, a "living with heart failure" questionnaire, blood tests and blood pressure and heart rate readings. Patients will then be crossed over to the alternate medication. Following 2 weeks on the target dose the patient will undergo their second study day which will be the same as the first. The results obtained from each study day will be compared.

Conditions