title: Sensitive detection of myocardial viability in chronic coronary artery disease by ultrasonic integrated backscatter analysis.
abstract: BACKGROUND
  Myocardial viability is not synonymous with contractile reserve and identifiable in a significant percentage of dysfunctional myocardial segments without contractile reserve. The usefulness of ultrasonic tissue characterization by the phase-corrected magnitude of cyclic variation of integrated backscatter (MVIB) in chronic coronary artery disease is not fully validated. Thus, whether MVIB predominantly reflects the contractile reserve or myocardial viability of chronically dysfunctional myocardium was determined.
  
  
  METHODS
  The MVIB of severely dysfunctional interventricular septum or posterior wall was measured in 34 consecutive patients with previous myocardial infarction. Dobutamine stress echocardiography and fluorine-18 fluorodeoxyglucose positron emission tomography were used as the standards of contractile reserve and myocardial viability, respectively.
  
  
  RESULTS
  Among 44 dysfunctional segments, only 15 were judged as having contractile reserve and 29 were judged as not by dobutamine stress echocardiography, whereas 26 segments showed myocardial viability using fluorine-18 fluorodeoxyglucose positron emission tomography and 18 did not. MVIB was greater in segments with than in those without contractile reserve (4.7 +/- 2.2 vs -1.4 +/- 4.9 dB, P < .0001), but there was considerable overlap between the groups. On the other hand, MVIB of segments with and without myocardial viability (4.1 +/- 2.6 vs -4.3 +/- 3.3 dB, P < .0001) was distinctly different and predicted myocardial viability with a sensitivity of 92% and a specificity of 94%.
  
  
  CONCLUSIONS
  For patients with chronic coronary artery disease, MVIB better reflects myocardial viability than it does contractile reserve. Ultrasonic tissue characterization, in concordance with fluorine-18 fluorodeoxyglucose positron emission tomography, is a sensitive method for detecting myocardial viability.
authors.affiliation: Department of Cardiovascular Medicine, Hokkaido University, Sapporo 060-8638, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Komuro
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yamada
authors.forename: Taisei
authors.initials: T
authors.lastname: Mikami
authors.forename: Keiichiro
authors.initials: K
authors.lastname: Yoshinaga
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Noriyasu
authors.forename: Kazutomo
authors.initials: K
authors.lastname: Goto
authors.forename: Hisao
authors.initials: H
authors.lastname: Onozuka
authors.forename: Kazushi
authors.initials: K
authors.lastname: Urasawa
authors.forename: Satoshi
authors.initials: S
authors.lastname: Fujii
authors.forename: Nagara
authors.initials: N
authors.lastname: Tamaki
authors.forename: Akira
authors.initials: A
authors.lastname: Kitabatake
mesh_terms: D000368:Aged; D002908:Chronic Disease; D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000473:pathology; D025401:Echocardiography, Stress; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18