Strain Rate Imaging by Ultrasound in the Diagnosis of Regional Dysfunction of the Left Ventricle

Abstract

BACKGROUND: Regional strain rate in the left ventricle can be assessed by tissue Doppler velocity gradient and color mapped in real time. Regional contractility thus can be visualized and graded. To validate the method, we made a comparison with standard echocardiography. METHODS AND RESULTS: Fifteen patients with recent myocardial infarction were examined with the use of strain rate imaging (SRI). Velocity gradients were mapped by color. Gray-scale 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 off line. 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 segments, 235 segments were analyzable by 2-D echo and 218 segments were analyzable 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 equal score by the two methods: 51 segments differed by 1 degree and 14 segments differed by 2 degrees (kappa = 0.45). CONCLUSIONS: SRI agrees well with echocardiography in grading regional wall function, and the method can be seen as validated in a clinical setting for assessment of regional systolic wall function and is demonstrated to be applicable for semiquantitative wall motion assessment. SRI has theoretical advantages and may be a valuable addition to standard echocardiography, especially in the field of stress echocardiography.

Left Ventricular Systolic and Diastolic Function in Patients With Apical Ballooning Syndrome Compared With Patients With Acute Anterior ST-Segment Elevation Myocardial Infarction: A Functional Paradox

“…[1][2][3][4][5] The objectives of this study were to compare 2-dimensional Doppler echocardiographic and SRI features of patients with ABS and AMI and to evaluate systolic and diastolic parameters associated with myocardial viability.…”

“…1 Early experimental and clinical studies have shown that SRI can not only differentiate abnormal from normal myocardial contractility during the initial phase of an infarction but can also demonstrate subsequent recovery of transient ischemia. [1][2][3][4][5] The objectives of this study were to compare 2-dimensional Doppler echocardiographic and SRI features of patients with ABS and AMI and to evaluate systolic and diastolic parameters associated with myocardial viability.…”

“…All patients had elevated creatine kinase MB and troponin T release levels, but the peak concentration was much lower in the patients with ABS than in those with AMI (Table 1). In 13 patients with ABS, ST-segment elevation was observed in 10 (77%), and an abnormal Q wave was observed in 3 (23%), mostly in the leads of V [1][2][3][4] . STsegment depression was found in 1 patient (8%), 1 patient (8%) exhibited T-wave inversion without ST-segment shifts, and the remaining 1 patient (8%) had only an abnormal Q wave in V [1][2][3] .…”

Automatic Classification of Left Ventricular Regional Wall Motion Abnormalities in Echocardiography Images Using Nonrigid Image Registration

“…Two of these techniques are based on analyzing ultrasound radiofrequency (RF) signals [5][6][7][8][9][10][11][12][13][14][15][16][17]. The first method known as acoustic quantification is based on the detection of the interface between the tissue and the blood in each image.…”

“…The second approach known as Tissue Doppler Imaging (TDI) estimates velocity, and strain/strain-rate values of the LV myocardial wall. The different quantitative indices obtained from these parameters are proposed to characterize the RWM [12][13][14][15][16][17]. However, this method is very dependent on the signal to noise ratio of the Doppler data.…”