Phospho Di Esterase Inhibitors In Congestive Heart Failure

Abstract

Aggressive therapy is needed in the presence of resistance Acute Left Ventricular Failure, commonly seen after large Myocardial Infarction or following Cardio Pulmonary Bypass if myocardial function may be severely depressed. When Ac. pump failure is so severe that adequate ,Cardiac Output cannot be maintained, hypotension may ensure despite an ele vated Perepheral Resistance, presenting picture of cardiogenic shock. Catecholamines or other symp athomimetic ammies maybe required in this setting. These agents exert potent inotropic effects by stimul ation of the beta I. adrenergic receptors.Although structurally dissimilar from one another and from the methyxanthines, these agents appear to inhibit phosphodiesterase (PDE) fraction III, the cyclic AMP specific cardiac phosphodiesterase, selectively and potently. Blocking the normal breakdown of cyclic nucleobide by PDE should also increase intrac ellular cyclic AMP levels increase contractility. Alt hough the traditional PDE inhibitors, e.g., theophyll ine, exert this effect, hut they are non selective and non potent.