title: Serial ultrasound evaluation of intramyocardial strain after reperfused myocardial infarction reveals that remote zone dyssynchrony develops in concert with left ventricular remodeling.
abstract: This study noninvasively evaluated the development of left ventricular (LV) dyssynchrony following reperfused myocardial infarction (MI) in mice using an ultrasonic speckle-tracking method. Eight C57BL/6J mice were assessed by high-resolution echocardiography at baseline and at eight time-points following MI. Images were acquired at 1mm elevational intervals encompassing the entire LV to determine chamber volumes and radial strain. Receiver-operating characteristic (ROC) analysis of regional radial strain was used to segment the three-dimensional (3-D) LV into infarct, adjacent and remote zones. This in vivo segmentation was correlated to histologic infarct size (R = 0.89, p < 0.01) in a short-axis, slice-by-slice comparison. The onset of dyssynchrony during LV remodeling was assessed by standard deviation of time to peak radial strain in the infarct, adjacent and remote zones. It was discovered that the form of LV dyssynchrony that develops in the remote zone late after MI does so in concert with the progression of LV remodeling (R = 0.70, p < 0.05).
authors.affiliation: Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA.
authors.forename: Yinbo
authors.initials: Y
authors.lastname: Li
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Garson
authors.forename: Yaqin
authors.initials: Y
authors.lastname: Xu
authors.forename: Patrick A
authors.initials: PA
authors.lastname: Helm
authors.forename: John A
authors.initials: JA
authors.lastname: Hossack
authors.forename: Brent A
authors.initials: BA
authors.lastname: French
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D018450:Disease Progression; D004452:Echocardiography / Q000379:methods*; D021621:Imaging, Three-Dimensional; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D015425:Myocardial Reperfusion; D010784:Photomicrography; D012372:ROC Curve; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D020257:Ventricular Remodeling