Inotropic and lusitropic abnormalities in the genesis of heart failure.

Cardiac pumping action is governed by two interdependent systems; those that govern contraction and the emptying of the heart (inotropic) and those that control its relaxation and filling (lusitropic). The signs and symptoms of 'heart failure' can be caused by abnormalities of either or both of these systems. Major technological advances in the evaluation of the cardiac patient, especially those that utilize measurements of ventricular volume, coupled with potent new drugs that can modify differently the inotropic and lusitropic properties of the myocardium, make it necessary to understand the role that each plays in the genesis of the clinical syndrome of heart failure.