Layer-specific strain analysis: investigation of regional deformations in a rat model of acute versus chronic myocardial infarction
Open Access
- 1 September 2012
- journal article
- research article
- Published by American Physiological Society in American Journal of Physiology-Heart and Circulatory Physiology
- Vol. 303 (5), H549-H558
- https://doi.org/10.1152/ajpheart.00294.2012
Abstract
Myocardial infarction (MI) injury extends from the endocardium toward the epicardium. This phenomenon should be taken into consideration in the detection of MI. To study the extent of damage at different stages of MI, we hypothesized that measurement of layer-specific strain will allow better delineation of the MI extent than total wall thickness strain at acute stages but not at chronic stages, when fibrosis and remodeling have already occurred. After baseline echocardiography scans had been obtained, 24 rats underwent occlusion of the left anterior descending coronary artery for 30 min followed by reperfusion. Thirteen rats were rescanned at 24 h post-MI and eleven rats at 2 wk post-MI. Next, rats were euthanized, and histological analysis for MI size was performed. Echocardiographic scans were postprocessed by a layer-specific speckle tracking program to measure the peak circumferential strain (SCpeak) at the endocardium, midlayer, and epicardium as well as total wall thickness SCpeak. Linear regression for MI size versus SCpeak showed that the slope was steeper for the endocardium compared with the other layers ( P < 0.001), meaning that the endocardium was more sensitive to MI size than the other layers. Moreover, receiver operating characteristics analysis yielded better sensitivity and specificity in the detection of MI using endocardial SCpeak instead of total wall thickness SCpeak at 24 h post-MI ( P < 0.05) but not 2 wk later. In conclusion, at acute stages of MI, before collagen deposition, scar tissue formation, and remodeling have occurred, damage may be nontransmural, and thus the use of endocardial SCpeak is advantageous over total wall thickness SCpeak.This publication has 35 references indexed in Scilit:
- Layer-specific strain analysis by speckle tracking echocardiography reveals differences in left ventricular function between rats and humansAmerican Journal of Physiology-Heart and Circulatory Physiology, 2010
- Speckle tracking imaging improves in vivo assessment of EPO-induced myocardial salvage early after ischemia-reperfusion in ratsAmerican Journal of Physiology-Heart and Circulatory Physiology, 2010
- A New Tool for Automatic Assessment of Segmental Wall Motion Based on Longitudinal 2D StrainCirculation: Cardiovascular Imaging, 2010
- Noninvasive Separation of Large, Medium, and Small Myocardial Infarcts in Survivors of Reperfused ST-Elevation Myocardial InfarctionCirculation: Cardiovascular Imaging, 2008
- Assessment of Segmental Myocardial Viability Using Regional 2-Dimensional Strain EchocardiographyJournal of the American Society of Echocardiography, 2007
- Comparison of Two-Dimensional Speckle and Tissue Velocity Based Strain and Validation With Harmonic Phase Magnetic Resonance ImagingThe American Journal of Cardiology, 2006
- Rat models of myocardial infarctionThrombosis and Haemostasis, 2006
- Towards new understanding of the heart structure and functionEuropean Journal of Cardio-Thoracic Surgery, 2005
- High mortality early reinfarction with first nontransmural myocardial infarctionAmerican Heart Journal, 1984
- Multivariate analysis of angiographic, histologic, and electrocardiographic data in patients with coronary heart disease.Circulation, 1984