Beta-blockers in chronic heart failure: what have we learned? What do we still need to know?

Current heart failure guidelines mandate the use of beta-blockers in patients with symptomatic systolic heart failure. In the past 12-18 months, there have been several reported advances in our understanding of beta-blocker therapy for heart failure. Despite these advances, there remain several unanswered questions with regard to beta-blockers. These involve, firstly, clarifying the underlying mechanisms of action of beta-blockers; secondly, further analysing patients with systolic heart failure who are not well-studied in major clinical trials (e.g. the elderly); thirdly, investigating unexplored indications for beta-blockers in heart failure; and finally, directly examining the clinical relevance of pharmacological differences among agents. The impact of genetic polymorphisms on the response to beta-blocker therapy, as well as interaction of these agents with future heart failure therapies, requires extensive investigation.