[Pharmacodynamic study of myocardial contraction using ultrasonic echography during isoproterenol perfusion in the...

An echographic study, both before and under isoproterenol infusion, was performed on 50 normal subjects. The movements of the posterior wass of the left ventricle were found to be averagely increased of 62% as regards the amplitude, 114% for the mean speed and 124% for the maximum speed of contraction. The transcerse diameter of the left ventricular cavity decreased by 5.25%. The circumferential fibres shortening speed expressed in circumference by second increased by 128%. An uninvasive method, echography, as cineangiography, makes it possible to assess the myocardial contractility on the basis of measurement of the average speed of circumferential fibres and of the diameter of the left ventricle.