Determination of the time course of left ventricular wall stress and velocity of fiber shortening in man by simultaneous left ventricular pressure and echocardiographic recording: preliminary report.

Overview

This report presents a method for determining the time course of circumferential LV wall stress and fiber shortening velocity (endocardial as well as midwall) using simultaneous recordings of LV dimensions by echography and LV pressure (micromanometer). The values for max VCF, VCF at peak stress, mean VCF, and peak stress are in general agreement with those observed with previous methods; the separation between normal and abnormal LV function appears to be good. The method permits frequent observations to be performed in a single patient, which is of particular value during acute interventions. Data from a small number of interventions suggest that VCF in man is relatively insensitive to acute changes in preload, is inversely affected by changes in afterload and appears sensitive to inotropic stimulation. Although VCF seems to be a good index of LV performance, its sensitivity to afterload might, at times, limit its usefulness.