title: Collateral-flow measurements in humans by myocardial contrast echocardiography: validation of coronary pressure-derived collateral-flow assessment.
abstract: OBJECTIVE
  Myocardial blood flow (MBF) is the gold standard to assess myocardial blood supply and, as recently shown, can be obtained by myocardial contrast echocardiography (MCE). The aims of this human study are (i) to test whether measurements of collateral-derived MBF by MCE are feasible during elective angioplasty and (ii) to validate the concept of pressure-derived collateral-flow assessment.
  
  
  RESULTS
  Thirty patients with stable coronary artery disease underwent MCE of the collateral-receiving territory during and after angioplasty of 37 stenoses. MCE perfusion analysis was successful in 32 cases. MBF during and after angioplasty varied between 0.060-0.876 mL min(-1) g(-1) (0.304+/-0.196 mL min(-1) g(-1)) and 0.676-1.773 mL min(-1) g(-1) (1.207+/-0.327 mL min(-1) g(-1)), respectively. Collateral-perfusion index (CPI) is defined as the rate of MBF during and after angioplasty varied between 0.05 and 0.67 (0.26+/-0.15). During angioplasty, simultaneous measurements of mean aortic pressure, coronary wedge pressure, and central venous pressure determined the pressure-derived collateral-flow index (CFI(p)), which varied between 0.04 and 0.61 (0.23+/-0.14). Linear-regression analysis demonstrated an excellent agreement between CFI(p) and CPI (y=0.88 x +0.01; r(2)=0.92; P<0.0001).
  
  
  CONCLUSIONS
  Collateral-derived MBF measurements by MCE during angioplasty are feasible and proved that the pressure-derived CFI exactly reflects collateral relative to normal myocardial perfusion in humans.
authors.affiliation: Department of Cardiology, University Hospital Bern, CH-3010 Bern, Switzerland.
authors.forename: Rolf
authors.initials: R
authors.lastname: Vogel
authors.forename: Rainer
authors.initials: R
authors.lastname: Zbinden
authors.forename: Andreas
authors.initials: A
authors.lastname: Indermühle
authors.forename: Stephan
authors.initials: S
authors.lastname: Windecker
authors.forename: Bernhard
authors.initials: B
authors.lastname: Meier
authors.forename: Christian
authors.initials: C
authors.lastname: Seiler
mesh_terms: D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure; D003097:Collateral Circulation / Q000502:physiology*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000503:physiopathology*; D003326:Coronary Circulation / Q000502:physiology*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging / Q000503:physiopathology; D004452:Echocardiography / Q000592:standards; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged