Arterial vasodilator therapy in heart failure: haemodynamic response patterns predictive of changes in exercise capacity

In a comparative study of the effects of felodipine versus placebo in 10 patients with heart failure all patients decreased systemic vascular resistance and increased cardiac index not only at rest but also during exercise. We tested the hypothesis that vasodilator therapy would enhance ExC if it were able to alter the load facing the heart in such a way that the cardiac pump needed to impart less hydraulic power output to maintain the same degree of physical exercise