Persistence of myocardial failure following removal of chronic volume overload

PRIVITERA. Persistence of myocardial failure following re-moval of chronic volume overload. Am. J. Physiol. 243 (Heart Circ. Physiol. 12): H876-H883, 1982.-Length-contractile force curves and dose-response curves of heart rate, blood pressure, and contractile force were recorded from the left ventricle of six anesthetized dogs in a control state. These measurements were repeated at an average of 56 days following creation of an atrioventricular fistula when signs of heart failure were present. The Estula was then closed and the dogs restudied after an additional 57 days. Heart failure was associated with a shift up the ascending limb of a depressed length-contractile force curve and a depressed contractile response to isoproterenol. For in-stance, 0.1 pg/kg of isoproterenol produced a 173 * 8 % increase in contractile force in control and 42 & 7 % in failure. The contractile response to ouabain (30 pg/kg) was unchanged i