title: Noninvasive coronary flow velocity reserve measurement in the posterior descending coronary artery for detecting coronary stenosis in the right coronary artery using contrast-enhanced transthoracic Doppler echocardiography.
abstract: BACKGROUND
  Coronary flow velocity reserve (CFVR) measurement by transthoracic Doppler echocardiography (TTDE) has been found to be useful for assessing left anterior descending coronary artery (LAD) stenosis. However, this method has been restricted only for the LAD. The purpose of this study was to detect severe right coronary artery (RCA) stenosis by CFVR measurement using contrast-enhanced TTDE.
  
  
  METHODS
  In 60 consecutive patients with angina pectoris (mean (SD) age: 60 (11), 18 women), coronary flow velocities in the RCA were recorded in the postero-descending coronary artery by contrast-enhanced TTDE at rest and during hyperemia induced by intravenous infusion of adenosine triphosphate (140 mcg/ml/kg). CFVR was calculated as the ratio of hyperemic to basal peak and mean diastolic flow velocity. CFVR measurements by TTDE were compared with the results of coronary angiography performed within 1 week.
  
  
  RESULTS
  Coronary flow velocity was successfully recorded in 49 (82%) of the 60 patients with contrast agent. CFVR (mean (SD)) was 1.4 (0.4) in patients with, and 2.6 (0.6) in patients without significant stenosis in the RCA (%diameter stenosis > 75%, P < 0.001). Using the cutoff value 2.0 for CFVR in the RCA, its sensitivity and specificity in detecting significant stenosis in the RCA were 88% and 91%, respectively.
  
  
  CONCLUSIONS
  CFVR measurement in the postero-descending coronary artery by contrast enhanced TTDE is a new, noninvasive method to detect significant stenosis in the RCA.
authors.affiliation: Department of Internal Medicine and Cardiology, Osaka City University Medical School, Osaka, Japan. watanabe@med.osaka-cu.ac.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Watanabe
authors.forename: Takeshi
authors.initials: T
authors.lastname: Hozumi
authors.forename: Kumiko
authors.initials: K
authors.lastname: Hirata
authors.forename: Ryo
authors.initials: R
authors.lastname: Otsuka
authors.forename: Kotaro
authors.initials: K
authors.lastname: Tokai
authors.forename: Takashi
authors.initials: T
authors.lastname: Muro
authors.forename: Kenei
authors.initials: K
authors.lastname: Shimada
authors.forename: Minoru
authors.initials: M
authors.lastname: Yoshiyama
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Takeuchi
authors.forename: Junichi
authors.initials: J
authors.lastname: Yoshikawa
mesh_terms: D000255:Adenosine Triphosphate; D000787:Angina Pectoris / Q000000981:diagnostic imaging / Q000503:physiopathology; D001783:Blood Flow Velocity / Q000502:physiology; D017023:Coronary Angiography; D003326:Coronary Circulation / Q000502:physiology*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity
chemical_list: D000255:Adenosine Triphosphate