title: Serial echocardiographic assessment of left ventricular dimensions and function after myocardial infarction in mice.
abstract: OBJECTIVE
  To test the usage of serial echocardiography in mice with induced myocardial infarct (MI) and to characterize the mouse model of MI.
  
  
  METHODS
  C57 mice underwent open-chest surgery to induce left coronary artery occlusion or sham-operation (SH). Echocardiography was performed before and at 1, 2.5, 6 and 9 weeks after surgery. Left ventricular end diastolic and end systolic dimensions (LVEDd, LVESd) and fractional shortening (FS) were measured. Haemodynamics was determined at week 9 by LV catheterization and hearts were examined morphologically.
  
  
  RESULTS
  Post-infarct mortality was 46% (10/22), of which, 70% died of acute heart failure or LV rupture within the first week. LV dimensions and FS remained stable in SH group (n = 10) during the study period. In surviving MI mice (n = 12), there was modest LV dilatation and fall in FS at week 1. Compared with week 0 values, there were progressive increase in LVEDd (+50(-)+66%) and LVESd (+124(-)+171%), and decline in FS (-53(-)-73%) during the 2.5-9 week period. Infarcted mice also had lower LV systolic pressure (LVSP), dP/dtmax and dP/dtmin (all P < 0.01 vs. SH group). Infarct size, LVSP and dP/dt significantly correlated with FS and LV dimensions (r = 0.61-0.80, all P < 0.01).
  
  
  CONCLUSIONS
  LV remodeling and dysfunction in mice with MI are time-dependent processes and early remodeling seems associated with high risk of rupture and acute pump failure. Our findings provide a baseline description of this murine model and confirm echocardiography as a reliable means to serially assess changes of cardiac structure and function after MI.
authors.affiliation: Experimental Cardiology Laboratory, Baker Medical Research Institute, Melbourne, Victoria, Australia.
authors.forename: X M
authors.initials: XM
authors.lastname: Gao
authors.forename: A M
authors.initials: AM
authors.lastname: Dart
authors.forename: E
authors.initials: E
authors.lastname: Dewar
authors.forename: G
authors.initials: G
authors.lastname: Jennings
authors.forename: X J
authors.initials: XJ
authors.lastname: Du
mesh_terms: D000818:Animals; D001794:Blood Pressure; D004452:Echocardiography; D006339:Heart Rate; D016014:Linear Models; D051379:Mice; D008810:Mice, Inbred C57BL; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D015588:Observer Variation; D011897:Random Allocation; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D020257:Ventricular Remodeling