LEFT ATRIUM WALL DEFORMATION PROPERTIES
Mitral regurgitation is the second most frequent indication for valve surgery [17]. The problem of a therapeutic decision during mitral valve insufficiency is quite timely. The unfavorable prognosis for disease depends largely on left ventricular dysfunction and levels of ventricular dysfunction are thoroughly studied. High level of ventricular dilation during mitral valve insufficiency is one surgical indication. Due to the fact that it is impossible to separate the contribution of coronary insufficiency and volume overload components to the process of left ventricular remodeling such parameters as ventricular size and left ventricular ejection fraction can't be used as parameters of hemodynamically relevant regurgitation [1, 7]. The role of the left atrium in global dilation of the heart against the backdrop of the mitral insufficiency is poorly studied. Left atrial dilation is powerful mortality prediction. It is well known that the atria contribution is essential to a ventricular ejection in the course of the left ventricular dysfunction. The strain and the strain rate of the left atrium are the prior markers of volume overload versus the dimensional changes [7]. The computer tomography experiment of the left atrium property investigation was set up in the Federal Center of Cardiovascular Surgery Named after S.G. Sukhanov in Perm. The experiment data technique was developed. Quantitative characteristics of displacement and strain of the left atrium wall were obtained as a result of data conditioning. The properties of the left atrium wall were analyzed and stress-strain curves were plotted along and across muscle fibers for different parts of the wall. The shear strain was found in the tangent plane of the left atrium.