[Correlation of the parameters of myocardial contraction and relaxation in compensatory cardiac hypertrophy].
The parameters of myocardial contraction and relaxation were determined from the left ventricular pressure curves obtained in closed chest rabbits. One month after the creation of ascending aorta stenosis when the relative weight of the left ventricle increased by 54% as compared to the control, systolic pressure was higher by 42% and maximum rate of pressure development by 47%. This increase corresponded to the degree of left ventricular hypertrophy so that the load on the unit of myocardial mass did not change. No changes were found in the contractility index. The index of relaxation, however, determined by the relation between the maximum rate of relaxation and the developed pressure and characterizing the function of the myocardial relaxation system was 20% lower than that of the control. This was associated with the decrease of the diastolic pause by 27%. The slowing down of relaxation is one of the first and must' signs of compensatory function of the heart.
D000818:Animals; D001024:Aortic Valve Stenosis / Q000503:physiopathology; D001795:Blood Pressure Determination / Q000379:methods; D006332:Cardiomegaly / Q000503:physiopathology*; D006352:Heart Ventricles / Q000503:physiopathology; D009126:Muscle Relaxation; D009200:Myocardial Contraction; D011817:Rabbits
Sootnoshenie parametrov sokrasheniia i rasslableniia serdechnoĭ myshtsy pri kompensatornoĭ gipertrofii serdtsa.