[Acute and chronic cardiac decompensation: is vasodilator therapy useful?]

Systemic vasodilators represent a new approach in the treatment of the acute and chronic heart failure, as they reduce the afterload acting on the aortic impedance and/or the venous return to the heart. Vasodilators have been classified as venodilators (nitrates), which reduce left ventricular filling pressure and relieve pulmonary congestion; arteriolar dilators (hydralazine, phentolamine) which enhance cardiac output; and balanced vasodilator (nitroprusside, prazosin), which dilate both resistance and capacitance vessels. While nitroprusside and phentolamine are used in the treatment of the acute myocardial infarction, nitrates, hydralazine and prazosin are used in the long term treatment of the chronic congestive heart failure. Presumably, the renin-angiotensin system plays an important role in increasing peripheric vascular resistance in congestive heart failure. For this reason the inhibitors of the angiotensin-converting enzyme, such as captopril and teprotide, are also used. The treatment with vasodilators, recommended to patients with severe heart failure, is not an alternative to that with digitalis and diuretics: such a combination may in fact result as a very useful one.