A STUDY OF PRESSURE-DIMENSION RELATIONSHIPS IN THE NORMAL CANINE LEFT VENTRICLE

(1) MEASUREMENTS OF THE INTERNAL MINOR DIMENSION OF THE LEFT VENTRICLE WITH A PULSE-TRANSIT ULTRASONIC METHOD

Abstract

We measured the internal minor dimension in the normal canine left ventricle using a pulse-transit ultrasonic method. In this report, we explained our methods and techniques, and analyzed the phasic patterns of the dimensional curve. We recognized that our methods and techniques were adequate to measure the internal dimension, and that its phasic patterns were similar to the other reports in the opened chest experiments. The phasic patterns of the dimensional curve were changed under the influencing of the experimental state (opened chest or concious), the site of the transducers in the endocardium and the heart rate. The simultaneous measuring of the pressure and the internal dimension of the left ventricle and the describing of its pressure-dimension loops are the fundamental for the evaluating of the cardiac function.