Strain rate imaging by ultrasound in the diagnosis of regional dysfunctionof the left ventricle

Background: Regional strain rate in the left ventricle can be assessed by t issue Doppler velocity gradient and color mapped in real time. Regional con tractility thus can be visualized and graded. To validate the method we mad e a comparison with standard echocardiography. Methods and Results: Fifteen patients with recent myocardial infarction were examined with the use of s train rate imaging (SRI). Velocity gradients were mapped by color. Gray-sca le imaging was performed using the second harmonic mode. Cine loops of two- dimensional echocardiography (2-D echo) and SRI images from three standard apical planes were analyzed offline. A four-grade scale in 16 segments was used to score wall motion by 2-D echo and by SRI. Of a total of 236 segment s, 235 segments were analyzable by 2-D echo and 218 segments were analyzabl e by SRI Correlation of wall motion score index with ejection fraction was -0.84 by 2-D echo and -0.92 by SRI. One hundred fourteen, segments had an e qual score by the two methods: 51 segments differed by 1 degree and 14 segm ents differed by 2 degrees (kappa = 0.45), Conclusions: SRI agrees well wit h echocardiography in grading regional wall function, and the method can be seen as validated in a clinical setting for assessment of regional systoli c wall function and is demonstrated to be applicable for semiquantitative w all motion assessment. SRI has theoretical advantages and may be a valuable addition to standard echocardiography, especially in the field of stress e chocardiography.