[Passive diastolic properties of the left ventricle during development of cardiac hypertrophy].
Induced insufficiency of the aortal valve in rabbits is followed by gradual adaptation of the heart to volume load. In the period of developing hypertrophy, we studied the changes in the passive diastolic properties of the ventricle. By analyzing the passive relationship between the volume of the ventricular cavity and the intraventricular pressure, the stiffness of the ventricle, normalized ventricular stiffness, and myocardial stiffness were determined. On day 30 after inducing the volume verload, the stiffness constant of the ventricle was statistically significantly reduced, whereas the constant of normalized ventricular stiffness and the constant of myocardial stiffness were statistically significantly increased. The increased stiffness of the myocardium, which characterizes the volume verloaded, left ventricle in the period of developing hypertrophy, may represent one of the changes causing reversal of the adaptive response of the heart to hemodynamic verload after a certain period of time, gradually resulting in the development of the syndrome of heart failure.