Neil Fam, BSc, MSc
Heart failure can be defined as a pathophysiological syndrome in which the heart fails to pump an adequate flow of blood to meet the metabolic demands of the body. This condition carries extremely high morbidity and mortality, with a five year survival rate of 50%. It is also one of the most common reasons for hospital admission in Canada. As our population ages, heart failure is becoming increasingly prevalent, placing serious strain on health care resources. In the past decade, medications such as angiotensin converting enzyme (ACE) inhibitors have been shown to improve survival in patients with heart failure. However, mortality has remained high. New research has focused on the use of b-blockers, a class of drugs traditionally used in the treatment of angina and myocardial infarction. Recently, two large randomised trials, the Cardiac Insufficiency Bisoprolol Study II (CIBIS-II) and the Metoprolol CR/XL Randomized Intervention Trial in Congestive Heart Failure (MERIT-HF) clearly demonstrated a survival benefit in heart failure patients taking b-blockers. This article summarizes the main findings of these studies and outlines the practical use of b-blockers in heart failure.
An understanding of the pathophysiology underlying heart failure is helpful in the selection of appropriate medical therapy.
