β-Blockers in hypertension, diabetes, heart failure and acute myocardial infarction: a review of the literature

β-Blockers (BBs) are an essential class of cardiovascular medications for reducing morbidity and mortality in patients with heart failure (HF). However, a large body of data indicates that BBs should not be used as first-line therapy for hypertension (HTN). Additionally, new data have questioned the role of BBs in the treatment of stable coronary heart disease (CHD). However, these trials mainly tested the non-vasodilating β1 selective BBs (atenolol and metoprolol) which are still the most commonly prescribed BBs in the USA. Newer generation BBs, such as the vasodilating BBs carvedilol and nebivolol, have been shown not only to be better tolerated than non-vasodilating BBs, but also these agents do not increase the risk of diabetes mellitus (DM), atherogenic dyslipidaemia or weight gain. Moreover, carvedilol has the most evidence for reducing morbidity and mortality in patients with HF and those who have experienced an acute myocardial infarction (AMI). This review discusses the cornerstone clinical trials that have tested BBs in the settings of HTN, HF and AMI. Large randomised trials in the settings of HTN, DM and stable CHD are still needed to establish the role of BBs in these diseases, as well as to determine whether vasodilating BBs are exempt from the disadvantages of non-vasodilating BBs.