Quantification of Instantaneous Extension and Contraction of in vivo Myocardial Fiber

摘要

A modified myocardium-blood composite model enables the temporal changes in instantaneous extension and contraction of in vivo myocardial fiber to be computed by using the measured blood volume fractions and wall thicknesses in the investigated left ventricular region. A 16 time-increment study of 6 dogs shows that myocardial fiber may undergo an average length change of 62% and -38% during the diastolic and systolic phases of cardiac cycle, respectively. Two comparable results had been obtained previously, but the new method is much simpler, removes the incompressibility assumption and takes into consideration the intravascular blood in the ventricular wall.