title: Quantification of myocardial blood flow and assessment of its transmural distribution with real-time power modulation myocardial contrast echocardiography.
abstract: BACKGROUND
  The purpose of this study was to examine the ability of real-time myocardial contrast echocardiography (MCE) with power modulation to quantitate myocardial blood flow (MBF) and to assess its transmural distribution in open-chest dogs undergoing partial or total coronary stenoses.
  
  
  RESULTS
  MBF was measured in 12 dogs instrumented with a cuff occluder around the left anterior descending coronary artery at rest, during partial coronary stenosis (during infusion of adenosine), and during coronary occlusion. The MCE-derived rate of microbubble velocity, beta, and myocardial blood volume, A, were obtained by curve fitting of videointensity versus time plots, after the transient destruction of microbubbles by high-energy ultrasound. The data were compared with MBF measured with radiolabeled microspheres. Significant correlations were found between radiolabeled microsphere-derived MBF and both beta (r = 0.93) and the product of A x beta (r = 0.91). MCE beta reserve also correlated well with microsphere-derived flow reserve. Comparing endocardial/epicardial MCE ratios and microsphere-derived MBF ratios, significant correlation was also found between endomicropsheres/epimicrospheres MBF ratio and both endo/epi beta (r = 0.90) and endo/epi A x beta (r = 0.88).
  
  
  CONCLUSIONS
  Real-time power modulation MCE allows for an accurate quantification of MBF and of its transmural distribution in open-chest dogs undergoing partial or total coronary stenoses.
authors.affiliation: Dvision of Cardiology, Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: Guy
authors.initials: G
authors.lastname: Van Camp
authors.forename: Taniyel
authors.initials: T
authors.lastname: Ay
authors.forename: Agnès
authors.initials: A
authors.lastname: Pasquet
authors.forename: Virginie
authors.initials: V
authors.lastname: London
authors.forename: Anne
authors.initials: A
authors.lastname: Bol
authors.forename: Giovanna
authors.initials: G
authors.lastname: Gisellu
authors.forename: Guy
authors.initials: G
authors.lastname: Hendrickx
authors.forename: Patrick
authors.initials: P
authors.lastname: Rafter
authors.forename: Jacques A
authors.initials: JA
authors.lastname: Melin
authors.forename: Jean-Louis J
authors.initials: JL
authors.lastname: Vanoverschelde
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D003326:Coronary Circulation / Q000502:physiology*; D003327:Coronary Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology; D004195:Disease Models, Animal; D004285:Dogs; D004452:Echocardiography; D004699:Endocardium / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D006339:Heart Rate / Q000502:physiology; D008297:Male; D008955:Models, Cardiovascular; D009200:Myocardial Contraction / Q000502:physiology; D009206:Myocardium / Q000737:chemistry*; D010496:Pericardium / Q000000981:diagnostic imaging / Q000503:physiopathology; D012720:Severity of Illness Index; D013223:Statistics as Topic; D013318:Stroke Volume / Q000502:physiology