title: Circumferential Strain Can Be Used to Detect Lipopolysaccharide-Induced Myocardial Dysfunction and Predict the Mortality of Severe Sepsis in Mice.
abstract: Sepsis-induced myocardial dysfunction is a common and severe complication of septic shock. However, conventional echocardiography often fails to reveal myocardial depression in severe sepsis. Recently, strain measurements based on speckle tracking echocardiography (STE) have been used to evaluate cardiac function.
  
  
  
  To investigate the role of STE in detecting lipopolysaccharide (LPS)-induced cardiac dysfunction, M-mode and 2-D echocardiography were used in LPS-treated mice.
  
  
  
  The mice were treated with a 10mg/kg (n = 10), 20mg/kg (n = 10) or 25mg/kg LPS (n = 30) to induce cardiac dysfunction. Subsequently, the ejection fraction (EF) and fractional shortening (FS) were measured with standard M-mode tracings, whereas the circumferential (Scirc) and radial strain (Srad) were measured with STE. Serum biochemical and cardiac histopathological examinations were performed to assess sepsis-induced myocardial injury.
  
  
  
  20mg/kg LPS resulted in more deterioration, myocardial damage and cardiac contractile dysfunction based on serum biochemical and histological examinations. The mice that were subjected to 20mg/kg LPS exhibited reduced Scirc but no reduction in Srad, whereas on conventional echocardiography, the ejection fraction (EF) and fractional shortening (FS) were similar in the 10mg/kg and 20mg/kg groups. Moreover, Scirc was positively correlated with body temperature in the mice at 20 h after LPS injection (r = 0.746, p = 0.001), but no significant correlation was observed between Srad and body temperature (r = 0.356, p = 0.123). Moreover, the mice with high Scirc (-5.9% to -10.4%) exhibited reduced mortality following the administration of 25mg/kg LPS (p = 0.03) compared with the low-strain group (-2% to -5.9%).
  
  
  
  Taken together, our findings indicate that circumferential strain is a specific and reliable indicator for evaluating LPS-induced cardiac dysfunction in mice.
authors.affiliation: Department of Geriatrics, First Affiliated Hospital with Nanjing Medical University, Nanjing, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Chu
authors.affiliation: Department of Geriatrics, First Affiliated Hospital with Nanjing Medical University, Nanjing, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Departments of Genetics, Pediatrics and Medicine (Cardiology), Albert Einstein College of Medicine of Yeshiva University, New York, United States of America.|Department of Cardiology, First Affiliated Hospital with Nanjing Medical University, Nanjing, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
authors.affiliation: Departments of Genetics, Pediatrics and Medicine (Cardiology), Albert Einstein College of Medicine of Yeshiva University, New York, United States of America.|Department of Cardiology, First Affiliated Hospital with Nanjing Medical University, Nanjing, China.
authors.forename: Bingruo
authors.initials: B
authors.lastname: Wu
authors.affiliation: Department of Geriatrics, First Affiliated Hospital with Nanjing Medical University, Nanjing, China.
authors.forename: Junhong
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Geriatrics, First Affiliated Hospital with Nanjing Medical University, Nanjing, China.
authors.forename: Di
authors.initials: D
authors.lastname: Xu
mesh_terms: D000818:Animals; D015415:Biomarkers; D009202:Cardiomyopathies / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology*; D004195:Disease Models, Animal; D004452:Echocardiography / Q000379:methods; D006334:Heart Function Tests; D008070:Lipopolysaccharides / Q000009:adverse effects*; D008297:Male; D051379:Mice; D009026:Mortality; D018805:Sepsis / Q000150:complications* / Q000382:microbiology / Q000401:mortality*; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D008070:Lipopolysaccharides