Evaluation of regional myocardial viability in rats after acute myocardial infarction with two-dimensional speckle tracking imaging
- VernacularTitle:超声二维斑点追踪成像技术评价大鼠急性心肌梗死后局部心肌存活性
- Author:
Qian FU
;
Mingxing XIE
;
Xinfang WANG
;
Qing LV
;
Lingyun FANG
;
Jing WANG
;
Li YUAN
;
Long CHENG
;
Feixiang XIANG
- Publication Type:Journal Article
- Keywords:
Echocardiography;
Ventricular function,left;
Myocardial infarction;
Two-dimensional strain
- From:
Chinese Journal of Medical Imaging Technology
2010;26(4):623-626
- CountryChina
- Language:Chinese
-
Abstract:
Objective To observe the value of two-dimensional speckle tracking imaging (2D-STI) in assessing regional myocardial viability of rats after acute myocardial infarction. Methods Twenty Wistar rats were randomly divided into acute myocardial infarction group and sham-operation group (each n=10). Echocardiography was performed at baseline and 24 h after reperfusion. High frame rate two-dimensional images were recorded from the left ventricular short-axis views at the papillary muscle level. Peak radial strain (PRS) and peak circumferential strain (PCS) of each segment were measured at systolic period. Left ventricular internal diameter at diastole (LVID_d) and systole (LVID_s), fractional shortening (FS), ejection fraction (EF), wall thickening rate (TR) were measured with anatomical M-model echocardiography. Area of necrosis (AN) of each segment was measured after triphenyl tetrazolium chloride (TTC) staining. Based on TTC staining, ROC curve was used to analyze the accuracy of two-dimensional strain and TR index in identifying infarcted segment. Results ①Compared with acute myocardial infarction group at baseline and sham-operation group after operation, LVID_d and LVID_s of acute myocardial infarction group after operation increased significantly respectively (P<0.05), FS, EF and anteroseptal wall TR reduced significantly (P<0.05). ②Compared with acute myocardial infarction group at baseline and sham-operation group after operation, PRS and PCS decreased significantly in anteroseptal, anterior, anterolateral, inferolateral and inferoseptal segments of myocardial infarction group after operation (P<0.05), especially in anterosepetal, anterior and anterolateral segments (P<0.05). ③ROC analysis showed PCS had the best ability to identify infarcted myocardium as defined by AN>50%. Using a cut-off of -6.14%, PCS had a sensitivity of 93.75% and specificity of 90.91% for distinguishing infarcted from viable myocardium. Conclusion 2D-STI can accurately quantify regional myocardial function, providing a sensitive and noninvasive means to assess regional myocardial viability.
