[Clinical evaluation of drugs in chronic cardiac failure]

As the acute complications of cardiovascular diseases are better controlled, the number of patients with chronic heart failure will no doubt increase, together with the need for new treatments of this condition. The effectiveness of these new drugs on the heart function and on the patient's functional status, quality of life and survival must be assessed by very strict evaluation methods. Evaluating the cardiac function requires haemodynamic investigations by proven techniques. Even when taken globally, the haemodynamic values do not always provide information on the patient's clinical and functional status which must therefore be assessed separately, using specific methods. The exercise load, duration and oxygen peripheral consumption measured by established techniques are, in fact, the variables best correlated with the patient's functional status. The effects of drugs must be evaluated at rest and during exercise, but also in short and long term, with a systematic search for tachyphylaxis. Improvements in much less than quality of life much greater than and tolerance of treatment can be evaluated by appropriate questionnaires filled in by the patients. Assessing the effect of any treatment on survival of cardiac patients is always difficult. It requires epidemiological studies which are invariably delicate and costly but cannot be avoided for such an important matter.