Use of ejection fraction (or lack thereof), morbidity/mortality and heart failure drug trials: a review

Ejection fraction (EF) is an ejection phase parameter used to assess the performance of the heart in normal individuals and pathologic states such as myocardial infarction, dilated cardiomyopathy, and congestive heart failure (CHF). It can be measured by radionuclide ventriculography, angiocardiography, echocardiography and magnetic resonance imaging. EF is dependent on the loading conditions of the heart as well as contractility of the myocardium which makes it a less useful measure of cardiac performance. Nevertheless, it has been widely utilized and discussed for years. EF has been used as an entry criteria for many trials in CHF and has been used to characterize the hemodynamic effects of various classes of drugs which are used in treating CHF. How predictive an increase in EF on therapy is of morbidity and mortality is a matter of debate. This review outlines the utilization (or lack thereof), of EF in various CHF drug trials, its relationship to symptomatic improvement and morbidity/mortality.