Evaluation Left Ventricular Myocardial Function In Myocardial Infarction Patients Using Two-Dimensional Strain Imaging

Objectives: (1) To investigate the characteristics and consistency of two-dimensional strain (2DS) and tissue velocity imaging (TVI) in the measurement of myocardial strain and strain rate of normal subjects. (2) To evaluate the clinical value of two-dimensional strain (2DS) and tissue velocity imaging (TVI) in quantifing infarction myocardial regional function.Methods: 2DS and TVI were performed in 30 healthy volunteers. Regional longitudinal peak systolic strain (LS) and strain rate (LSR) were measured by two methods from the apical four-chamber view, two-chamber view and long-axis view of the left ventricular and compared; Two-dimensional gray-scale images with tissue velocity imaging from apical two-chamber view were acquired with 26 LV anterior wall myocardial farction. Regional longitudinal peak systolic strain (LS) and strain rate (LSR) which measured by two methods were matched separately with normal subjects; Radial two-dimensional gray-scale images in mitral plane, papillary muscle plane, apical plane were acquired with 30 healthy volunteers and 26 LV anterior wall myocardial farction. Normal regional radial peak systolic strain (LS) and strain rate (LSR) of LV inferior and anterior wall by 2DS were compared with those of control.Results: (1) Left ventricular two-dimensional LS gradually increased from the base to apex(basal segmentmiddle segment>apical segment); were the biggest in middle segments of inferior and ant-septa and the minimum in apical segments of inferior and ant-septa; gradually increased from the base to apex in septa ( basal segment0.05); The LS in myocardial infarction patients obtained by 2DS were significantly different from those in the control's all segments of anterior(P<0.05), LSR between two groups were significantly different in the apical segments of anterio(rP<0.05). (3) The radial strain (RS) in myocardial infarction patients obtained by 2DS were significantly different from those in the contol's basal segments of anterior wall(P<0.05). The radial strain rate (RSR) were no significantly different between two groups(P>0.05).Conclusion: (1) Characteristic of longitudinal strain and strain rate from the base to apex are inconsistent between left ventricular 2DS and TVI. Left ventricular 2DS longitudinal strain gradually increased from the base to apex (basal segment