[Echocardiography in studying the indices of myocardial contractile function]

In the assessment of most informative indices for studying the myocardial contractility based on electrocardiographic findings, 10 parameters at rest and at the peak of isoprenaline action (a positive inotropic agent) were estimated and analyzed. The study involved 30 apparently healthy people aged from 20 to 89 years. Using the method of major components, the initial information was condensed by excluding less informative characteristics. Eventually 4 parameters were selected which can be proposed for study of myocardial contractility by means of echocardiography: normalized systolic ejection rates for the first third of systolic ejection; percent of stroke volume ejected for the first third of systole; mean normalized velocity of circumferential fiber shortening; and peak rate of decrease of left ventricular dimension during systole.