[Methods for evaluating medical treatments of chronic cardiac insufficiency]

As with any therapeutic intervention, in the evaluation of medical treatment of chronic cardiac failure, methods of assessing the efficacy of the drug (for example, measuring haemodynamic parameters) have to be distinguished from those designed to show therapeutic benefit (for example, prolongation of survival, quantified improvement in performance without excess mortality or deterioration in the quality of life). Studies of survival are long and costly and, as yet, have been conducted only in advanced stages of the disease. They are difficult to set up before the drug has been approved for general use i.e. when the only indication is the treatment of cardiac failure. If a criterion of substitution is not validated, the evaluation of the effects of the drug on quantified performances remains essential in pilot studies and phase 3 trials despite their artificial appearances. These trials are difficult to coordinate as they are usually multicenter and relatively prolonged (at least 6 months) studies.