title: An alternative to radioactive microsphere for measuring regional myocardial blood flow, Part 2: Laser-Doppler perfusion monitor.
abstract: OBJECTIVE
  To compare measurements of regional myocardial blood flow volume between microsphere measurement of regional flow (0.5- to 2- g tissue sampling) and a potential alternative measure, local flow (1 mm3) in the microcirculation measured by laser-Doppler perfusion monitor.
  
  
  METHODS
  Prospective, randomized, controlled.
  
  
  METHODS
  University research laboratory.
  
  
  METHODS
  Pigs.
  
  
  METHODS
  After anesthetization, in 5 pigs (25 to 30 kg), the left anterior descending coronary artery was isolated and its resting flow measured by a perivascular-Doppler flowmeter. Left ventricular pressure and first time derivative of left ventricular pressure were measured. The laser-Doppler probe needle (type N) (Model ALF-21, Transonic Systems, Inc, Ithaca, NY) was inserted 2 to 3 mm into the wall of the left ventricle, parallel to the coronary artery. All 5 pigs were subjected to 0 (control), 50% , 75%, and 100% constriction of the left anterior coronary artery.
  
  
  RESULTS
  Measurements by radio-active microspheres correlated poorly with those by laser-Doppler and extremely poorly with those by perivascular Doppler flowmeter. For percent change from baseline in the constricted arterial zone, radioactive measurements correlated well with those by laser-Doppler but not those by Doppler flowmeter. Also, radioactive measurements of percent change in flow in the circumflex (nonconstricted) zone and laser-Doppler measurements in the constricted arterial zone did not correlate well.
  
  
  CONCLUSIONS
  Laser-Doppler can be recommended for experimental research to monitor local flow. These measurements may relate to change in regional flow during normal perfusion and hypoperfusion. Before the laser-Doppler perfusion monitor can be used clinically, tissue trauma from the 0.55-mm needle needs to be evaluated.
authors.affiliation: Department of Anesthesiology, University of Florida College of Medicine, Gainesville 32610-0254, USA.
authors.forename: A
authors.initials: A
authors.lastname: Sidi
authors.forename: W
authors.initials: W
authors.lastname: Rush
mesh_terms: D000818:Animals; D003326:Coronary Circulation; D003327:Coronary Disease / Q000175:diagnosis / Q000000981:diagnostic imaging; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology; D004867:Equipment Design; D017078:Laser-Doppler Flowmetry / Q000295:instrumentation*; D008863:Microspheres; D008991:Monitoring, Physiologic / Q000295:instrumentation; D017202:Myocardial Ischemia / Q000175:diagnosis / Q000000981:diagnostic imaging; D011446:Prospective Studies; D011868:Radioisotopes / Q000008:administration & dosage; D011877:Radionuclide Imaging; D011897:Random Allocation; D013552:Swine; D016277:Ventricular Function, Left; D017725:Ventricular Pressure
chemical_list: D011868:Radioisotopes