title: Noninvasive assessment of significant right coronary artery stenosis based on coronary flow velocity reserve in the right coronary artery by transthoracic Doppler echocardiography.
abstract: BACKGROUND
  Coronary flow velocity reserve (CFVR) measured by transthoracic Doppler echocardiography (TTDE) has been reported to be useful for the noninvasive assessment of coronary stenosis in the left anterior descending artery. However, the measurement of CFVR in the right coronary artery by TTDE has not yet been validated in a clinical study.
  
  
  OBJECTIVE
  The aim of this study was to evaluate whether CFVR by TTDE can detect significant stenosis in the right coronary artery.
  
  
  METHODS
  We studied 50 patients who underwent coronary angiography. Coronary flow velocity in the posterior descending branch of the right coronary artery (PD) was measured by TTDE both at baseline and during hyperemia induced by the intravenous infusion of adenosine triphosphate. CFVR was calculated as the hyperemia/baseline (average diastolic peak velocity).
  
  
  RESULTS
  Adequate spectral Doppler recordings in the PD were obtained in 36 patients including 26 patients who were given an echocardiographic contrast agent to improve Doppler spectral signals. The study population was divided into 2 groups with (Group A;n = 11) and without (Group B;n = 25) significant stenosis in the right coronary artery. CFVR in Group A was significantly smaller than that in Group B (1.6+/-0.3versus2.5+/-0.4; P < 0.0001). The sensitivity of a CFVR of <2.0 for predicting the presence of significant stenosis in the right coronary artery was 91%, and the specificity was 88%.
  
  
  CONCLUSIONS
  The measurement of CFVR in the PD by TTDE is useful for the noninvasive assessment of significant stenosis in the right coronary artery.
authors.affiliation: First Department of Internal Medicine, Shiga University of Medical Science, Otsu, Shiga Okamura Memorial Hospital, Shimizu, Shizuoka, Japan. uenoy@balle.shiga-med.ac.jp
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Ueno
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Masahiko
authors.initials: M
authors.lastname: Kinoshita
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Fujita
authors.forename: Taizou
authors.initials: T
authors.lastname: Sakamoto
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Okamura
mesh_terms: D000255:Adenosine Triphosphate; D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology; D016022:Case-Control Studies; D017023:Coronary Angiography; D003326:Coronary Circulation; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004452:Echocardiography; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D006940:Hyperemia / Q000139:chemically induced; D008297:Male; D012680:Sensitivity and Specificity; D016277:Ventricular Function, Left / Q000502:physiology
chemical_list: D000255:Adenosine Triphosphate