[Analysis of regional kinetics of the left ventricle by integration of morphologic data]

Regional left ventricular (LV) curvature analysis is a useful tool to assess the pathomorphological changes in LV shape which occur in different heart diseases. As LV shape changes follow regular trajectories, we used the curvature extrema and the normalized curvature variations as the features for identifying the movement of the borders during the cardiac cycle (curvature-motion method: CM). The regional curvature was calculated using a windowed Fourier series approximation of contours, in which the number of harmonics and filter-window were locally chosen in order to minimize the reconstruction errors and to maximize the smoothness of the curve. Analysis programs were tested on a series of ventricle-shaped contours, software generated. Left ventricular diastolic and systolic outlines obtained from RAO 30 degrees LV angiography in 24 patients with aortic insufficiency and in 16 subjects without heart disease were analyzed. Left ventricular curvature and regional wall motion were calculated in each subject. In respect to normal subjects, LV shape in aortic regurgitation definitely appears asymmetric because of the elongation of the anterior hemiperimeter and the prevailing expansion of the apical and anterolateral regions. These alterations in cavity geometry correlate to the decrease in pump function. According to these results wall motion analysis using the CM showed a greater extension of LV asynergy, while usual methods as the centerline or the radial one indicate a greater damage of the apical regions. Thus, the CM method seems to be a promising tool for wall motion analysis.