Evaluation of circumferential strain in rabbits with acute and chronic myocardial infarction by#br#
two-dimensional speckle tracking imaging
ZHOU Meng1, WU Jun1, FENG Yuan-bo2, QIN Hao-cheng1, LI Jie-ming1, WEN Xiao-na1, NI Yi-cheng2
1. Department of Ultrasound, the Second Affiliated Hospital of Dalian Medical University, Dalian Liaoning 116027, China;
2. Department of Radiology, Gasthuisberg Hospitals, Catholic University of Leuven, Leuven 3000, Belgium
Abstract:Objective: To evaluate the global myocardial circumferential strain and strain rate in rabbits with acute and chronic myocardial infarction by two-dimensional speckle tracking imaging. Methods: Twenty New Zealand rabbits with ligation of the left circumflex artery were observed as experimental group and 5 rabbits without ligation of the artery as control group. The degree of global myocardial circumferential strain(GCS) and strain rate(GSrC) at mitral valve, papillary muscle and apical level were compared by speckle tracking imaging before, one week and seven weeks after surgery, respectively. And the fate of the animals, cardiac magnetic resonance imaging(cMRI) and triphenyltetrazolium chloride(TTC) staining were studied for myocardial infarction sizes(MI size%). Results: Compared with the preoperative parameters, there were significant increases in GCS and GSrC one week after the surgery(P<0.05) at mitral valve level. Compared with those parameters 1 week postoperative, there were significant decreases in GCS and GSrC at the 7th week postoperative(P<0.05), which had no obvious changes than those of the basic status. Compared with the preoperative parameters, there were significant decreases in GCS and GSrC at the 1st and 7th week postoperative at papillary muscle and apical level(P<0.05), but there was no significant difference between the 1st and the 7th week postoperative. Conversely there were no much changes of the degree of GCS and GSrC of myocardium at each time point in the control group(P>0.05). The degree of GCS and GSrC of myocardium at papillary muscle level had correlations with LVEF(US), LVEF(cMRI) and MI size%(r=-0.943, -0.916, -0.749, -0.615, 0.807, 0.641, respectively, all P<0.05). Conclusion: Two-dimensional speckle tracking imaging can objectively quantify regional and global heart function in rabbits, and can help to analyze the location and size of the myocardial infarction.
[1]Feng Y, Xie Y, Wang H, et al. A modified rabbit model of reperfused myocardial infarction for cardiac MR imaging research[J]. Int J Cardiovasc Imaging, 2009, 25(3): 289-298.
[2]黄国倩,刘虹,舒先红,等. 超声心动图评价粒细胞集落刺激因子动员自身骨髓干细胞对心肌梗死后左心室重构及心功能的影响[J]. 中华超声影像学杂志,2004,13(11):848-852.
[3]Urheim S, Edvardsen T, Torp H, et al. Myocardial strain by Doppler echocardiography. Validation of a new method to quantify regional myocardial function[J]. Circulation, 2000, 102(10): 1158-1164.
[4]杨性安,郑哲岚. 斑点追踪技术评价急性前壁心肌梗死内外膜圆周应变[J]. 中国临床医学影像杂志,2011,22(9):662-664.
[5]Chan J, Hanekom L, Wong C, et al. Differentiation of subendocardial and transmural infarction using two-dimensional strain rate imaging to assess short-axis and long-axis myocardial function[J]. J Am Coll Cardiol, 2006, 48(10): 2026-2033.
[6]姜新魁,穆玉明,史琪,等. 不同时间段心肌梗死大鼠左心室心肌力学改变特点的斑点追踪显像研究[J]. 中华超声影像学杂志,2010,19(9):797-800.
[7]宋平梅,任卫东,乔伟,等. 应用斑点追踪技术对急性心肌缺血及再灌注心肌应变功能的研究[J]. 中国超声医学杂志,2013,29(8):726-729.
[8]Bachner-Hinenzon N, Malka A, Barac Y, et al. Strain analysis in the detection of myocardial infarction at the acute and chronic stages[J]. Echocardiography, 2016, 33(3): 450-458.
[9]Feng Y, Chen F, Xie Y, et al. Lipomatous metaplasia identified in rabbits with reperfused myocardial infarction by 3.0T magnetic resonance imaging and histopathology[J]. BMC Med Imaging, 2013, 13(1): 1-9.
[10]翟虹,穆玉明,王春梅,等. 兔室壁瘤形成过程心肌力学演变特点的斑点追踪显像研究[J]. 中国现代医学杂志,2015,25(6):8-13.
[11]Kihlberg J, Haraldsson H, Sigfridsson A, et al. Clinical experience of strain imaging using DENSE for detecting infarcted cardiac segments[J]. J Cardiovas Magn Reson, 2015, 17(1): 1-9.
[12]Wang Q, Huang D, Zhang L, et al. Assessment of Myocardial Infarct Size by Three-Dimensional and Two-Dimensional Speckle Tracking Echocardiography: A Comparative Study to Single Photon Emission Computed Tomography[J]. Echocardiography, 2015, 5(4): 255-258.