Proposal for a new clinical end point to evaluate the efficacy of drugs and devices in the treatment of chronic heart failure

Clinical trials designed to evaluate the effect of drugs and devices on the symptoms and clinical status in chronic heart failure have frequently prod uced conflicting, inconclusive, or misleading results. These difficulties c an be explained by the fact that previous studies have relied on efficacy m easures that have inherent limitations and have been analyzed using statist ical approaches that ignored episodes of clinical deterioration. Recognitio n of these pitfalls has led to the development of a new clinical composite score, which combines changes in the New York Heart Association class and t he global assessment together with the information provided from the occurr ence of major clinical events. Use of this score would have correctly disti nguished active therapy from placebo in earlier trials and thus would have avoided some of their misleading conclusions. The new clinical composite sc ore has been prospectively incorporated into the design of studies evaluati ng the efficacy of endothelin antagonists, cytokine antagonists, vasopressi n antagonists, and cardiac resynchronization in the treatment of chronic he art failure. In the trials that have been completed to date, the clinical c omposite score has been more sensitive than conventional approaches in disc erning the presence or absence of a true treatment effect.