Beta-blockers for chronic heart failure: surviving longer but feeling better?

Beta-blockers, as determined by four landmark placebo-controlled studies, impart a significant survival advantage to the chronic heart failure population. What ancillary benefits might be expected from beta-blockade, in terms of symptom relief and improvement in exercise capacity, is less clear. This situation in part reflects the heterogeneity of tools used to quantify quality of life and exercise performance as well as factors concerning the statistical handling of symptom and exercise data. In this review we explore the methodology and results of over 20 trials of carvedilol, metoprolol and bisoprolol where quality of life and measures of exercise capacity were end-points. A consistent message relating to a benefit from beta-blockade on these outcomes was elusive but the finding that patients on beta-blockers did at least as well as patients prescribed placebo was a unanimous verdict. There remains a dearth of data to help identify those patients that are at high risk of adverse events from beta-blocker therapy.