title: Ultrasonic integrated backscatter in early assessment of myocardial injury during open heart surgery.
abstract: OBJECTIVE
  The recovery of cyclic variation of ultrasonic integrated backscatter in myocardial ischemia provides early assessment of myocardial injury and is useful in assessing myocardial injury during open heart surgery.
  
  
  METHODS
  We studied 25 patients with valvular disease undergoing cardiac surgery--7 with aortic stenosis, 7 with aortic regurgitation, 6 with mitral stenosis, and 5 with mitral regurgitation. All underwent transesophageal echocardiography (before aortic cross-clamping: T-pre and 60 minutes after aortic declamping: T-60). The short-axis view at the papillary muscle level of the left ventricle was recorded and anterior areas were assessed.
  
  
  RESULTS
  The magnitude of cyclic variation at T-pre and T-60 was 9.4 +/- 2.5 dB and 8.8 +/- 3.0 dB, and the ratio was 97 +/- 32%. Fractional shortening at T-pre and at T-60 was 27 +/- 7% and 20 +/- 9%, and the ratio was 79 +/- 44%. Recovery of magnitude was ahead of recovery of fractional shortening. The percent recovery of magnitude at T-60 did not correlate with aortic cross-clamping time (p = 0.91), postoperative peak creatine kinase-MB (p = 0.4), or catecholamine dosage (p = 0.13), but correlated with preoperative left ventricular mass index (p < 0.01). In patients with aortic stenosis, the percent recovery of magnitude at T-60 (66 +/- 4%) was significantly lower than in those with other types of valvular disease.
  
  
  CONCLUSIONS
  The recovery of magnitude of cyclic variation of ultrasonic integrated backscatter provides early assessment of myocardial injury, particularly in severely hypertrophied hearts, during reperfusion after aortic declamping in open heart surgery.
authors.affiliation: Department of Surgery, Course of Interventional Medicine (El), Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Maeda
authors.forename: N
authors.initials: N
authors.lastname: Hirata
authors.forename: Y
authors.initials: Y
authors.lastname: Sawa
authors.forename: S
authors.initials: S
authors.lastname: Ohtake
authors.forename: S
authors.initials: S
authors.lastname: Takiuch
authors.forename: H
authors.initials: H
authors.lastname: Matsuda
mesh_terms: D000328:Adult; D000368:Aged; D001022:Aortic Valve Insufficiency / Q000601:surgery; D001024:Aortic Valve Stenosis / Q000601:surgery; D006348:Cardiac Surgical Procedures; D003402:Creatine Kinase / Q000097:blood; D052279:Creatine Kinase, MB Form; D017548:Echocardiography, Transesophageal / Q000379:methods*; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000097:blood; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency; D008946:Mitral Valve Stenosis / Q000601:surgery; D015428:Myocardial Reperfusion Injury / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D016277:Ventricular Function, Left / Q000502:physiology
chemical_list: D007527:Isoenzymes; D003402:Creatine Kinase; D052279:Creatine Kinase, MB Form