title: Comparison of transesophageal coronary sinus and left anterior descending coronary artery Doppler measurements for the assessment of coronary flow reserve.
abstract: BACKGROUND
  Currently used methods for assessment of coronary flow reserve are invasive and require extensive laboratory equipment. Recently, noninvasive assessment of coronary flow reserve by transesophageal Doppler evaluation of coronary sinus (CS) or left anterior descending coronary artery (LAD) flow has been proposed. Direct comparison between these two techniques is lacking.
  
  
  METHODS
  Doppler recordings of CS and LAD flow velocity were obtained before and after 0.6 mg/kg/5 min dipyridamole in 16 patients with significant stenosis of the LAD (Group A) and in 14 control patients (Group B). Flow recordings and all measurements were performed in a blinded manner. For assessment of coronary flow reserve, Doppler measurements after dipyridamole were divided by the respective baseline values.
  
  
  RESULTS
  Doppler studies of the CS and LAD were feasible in 30 of 30 (100%) and 23 of 30 (71%) patients, respectively. Analyzing the maximum flow velocities, coronary flow reserve in Groups A and B was 1.18 +/- 0.28 and 1.68 +/- 0.53 with CS recordings and 1.78 +/- 0.83 and 2.51 +/- 0.76 with LAD recordings, respectively. Analyzing the velocity time integrals, coronary flow reserve in Groups A and B was 1.53 +/- 0.68 and 2.59 +/- 0.74 with CS recordings and 1.77 +/- 0.38 and 2.68 +/- 0.93 with LAD recordings, respectively. Correlation between LAD and CS recordings was 0.69 (p < 0.001), when coronary flow reserve was calculated from the velocity time integral and 0.68 (p < 0.001) when the maximum flow velocities were used.
  
  
  CONCLUSIONS
  Both transesophageal Doppler techniques might be useful for noninvasive assessment of coronary flow reserve.
authors.affiliation: Department of Cardiology, University of Vienna, Austria.
authors.forename: G
authors.initials: G
authors.lastname: Mundigler
authors.forename: M
authors.initials: M
authors.lastname: Zehetgruber
authors.forename: G
authors.initials: G
authors.lastname: Christ
authors.forename: P
authors.initials: P
authors.lastname: Siostrzonek
mesh_terms: D000328:Adult; D001158:Arteries; D001783:Blood Flow Velocity / Q000187:drug effects; D003326:Coronary Circulation; D003327:Coronary Disease / Q000503:physiopathology; D003331:Coronary Vessels / Q000503:physiopathology; D004176:Dipyridamole; D015150:Echocardiography, Doppler; D017548:Echocardiography, Transesophageal; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014680:Veins
chemical_list: D004176:Dipyridamole