title: Effects of heart rate and anesthetic timing on high-resolution echocardiographic assessment under isoflurane anesthesia in mice.
abstract: OBJECTIVE
  Anesthesia provides sedation and immobility, facilitating echocardiography in mice, but it influences cardiovascular function and therefore outcomes of measurement. This study aimed to determine the effect of the optimal heart rate (HR) and anesthetic timing on echocardiographic reproducibility under isoflurane anesthesia.
  
  
  METHODS
  Male C57BL/6J mice underwent high-resolution echocardiography with relative fixed HRs and anesthetic timing. The same experiment was repeated once again after 1 week.
  
  
  RESULTS
  Echocardiography was highly reproducible in repeated measurements under low-HR (350-400 beats per minute [bpm]) and high-HR (475-525 bpm) conditions except some M-mode parameters under low-HR conditions. With similar anesthetic timing, mice with a high HR had decreased preload indices and increased ejection phase and Doppler indices. Inversely, when the HR was similar, the echocardiographic results of mice under short anesthetic timing showed little difference from the ones under long anesthetic timing.
  
  
  CONCLUSIONS
  This study shows that echocardiographic assessment is greatly reproducible under a high HR. The HR is more important than anesthetic timing for echocardiographic evaluation in mice.
authors.affiliation: Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institutes of Biomedical Sciences, Fudan University, Shanghai, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Wu
authors.forename: Liping
authors.initials: L
authors.lastname: Bu
authors.forename: Hui
authors.initials: H
authors.lastname: Gong
authors.forename: Guoliang
authors.initials: G
authors.lastname: Jiang
authors.forename: Lei
authors.initials: L
authors.lastname: Li
authors.forename: Hong
authors.initials: H
authors.lastname: Ma
authors.forename: Ning
authors.initials: N
authors.lastname: Zhou
authors.forename: Li
authors.initials: L
authors.lastname: Lin
authors.forename: Zhidan
authors.initials: Z
authors.lastname: Chen
authors.forename: Yong
authors.initials: Y
authors.lastname: Ye
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Niu
authors.forename: Aijun
authors.initials: A
authors.lastname: Sun
authors.forename: Junbo
authors.initials: J
authors.lastname: Ge
authors.forename: Yunzeng
authors.initials: Y
authors.lastname: Zou
mesh_terms: D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D015150:Echocardiography, Doppler / Q000379:methods*; D006339:Heart Rate / Q000187:drug effects*; D007530:Isoflurane / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D015203:Reproducibility of Results
chemical_list: D018685:Anesthetics, Inhalation; D007530:Isoflurane