Promises and Disappointments of Vasodilator Treatment of Chronic Heart Failure

Abstract

A physiological approach to treatment is always academically satisfying but the results rarely live up to the early expectations. This has gradually become apparent with the increasing application of vasodilators in the treatment of patients with chronic heart failure. The exquisite implicity of the concept that reduction of the pressure against which the left ventricle has to pump would rejuvenate its performance is immensely attractive but sadly superficial. The immediate benefit to the failing heart of acute reduction in stretch of the myocardial fibres by reduction in after-load has been amply demonstrated in the isolated preparation, in the experimental animal and even in acute heart failure in man. Unfortunately, such reasoning ignores the crucial fact that in chronic heart failure vasodilator treatment is undertaken in the face of an innervated heart and largely intact neuro-humoral reflexes, the counter-effects of which may only become apparent after long-term treatment. The initial psychological resistance by physicians to such unusual treatment was followed by a surge of immense and uncritical enthusiasm for the therapeutic exhibition of these drugs in patients with chronic heart failure. However, the inadequate design and over-extended interpretation of many of the early studies in this field gradually eclipsed this rising wave of enthusiasm. Equally unfortunately, the waning popularity of this new approach has been accentuated by unwarranted disappointment, fuelled by the now fashionable cult of therapeutic nihilism (Fig. 1).