title: Noninvasive diagnosis of ischemic and nonischemic cardiomyopathy using coronary flow velocity measurements of the left anterior descending coronary artery by transthoracic Doppler echocardiography.
abstract: OBJECTIVE
  The purpose of this study was to assess the feasibility and usefulness of coronary flow velocity measurements of the left anterior descending coronary artery (LAD) by transthoracic Doppler echocardiography (TTDE) to differentiate ischemic cardiomyopathy (ICM) from non-ICM in patients.
  
  
  BACKGROUND
  ICM and non-ICM have similar 2-dimensional echocardiographic features, left ventricular dilatation, and diffuse wall-motion abnormalities. TTDE may be useful to differentiate ICM from non-ICM by detecting significant LAD stenosis based on LAD flow signal analysis.
  
  
  METHODS
  TTDE was performed in 52 consecutive patients with left ventricular dilatation and diffuse wall-motion abnormalities of unknown origin. Peak and averaged systolic and diastolic flow velocities of the distal LAD flow could be recorded and measured from 44 patients (85%). Peak and mean diastolic/systolic velocity ratio (DSVR) were calculated.
  
  
  RESULTS
  By coronary angiogram, 13 patients were given the diagnosis of ICM and 31 of non-ICM. Left ventricular end-diastolic and end-systolic volumes and ejection fraction were similar between ICM and non-ICM. On the other hand, peak DSVR (1.47 +/- 0.38 vs 2.34 +/- 0.67, P < .0001) and mean DSVR (1.40 +/- 0.42 vs 2.24 +/- 0.61, P < .0001) were significantly lower in patients with ICM than non-ICM. Either peak DSVR less than 1.8 or mean DSVR less than 1.8 had a sensitivity of 77% and a specificity of 77% for detecting the presence of severe LAD stenosis and, therefore, the diagnosis of ICM.
  
  
  CONCLUSIONS
  TTDE is a useful noninvasive method to differentiate ICM from non-ICM.
authors.affiliation: Division of Cardiology, Bell Land General Hospital, Sakai, Japan. hokura@fides.dti.ne.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Okura
authors.forename: Hiromi
authors.initials: H
authors.lastname: Fuyuki
authors.forename: Tomoichiro
authors.initials: T
authors.lastname: Kubo
authors.forename: Kazuya
authors.initials: K
authors.lastname: Iwata
authors.forename: Haruyuki
authors.initials: H
authors.lastname: Taguchi
authors.forename: Iku
authors.initials: I
authors.lastname: Toda
authors.forename: Junichi
authors.initials: J
authors.lastname: Yoshikawa
mesh_terms: D000368:Aged; D001783:Blood Flow Velocity; D009202:Cardiomyopathies / Q000145:classification* / Q000000981:diagnostic imaging* / Q000209:etiology; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D004452:Echocardiography; D015150:Echocardiography, Doppler; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000150:complications / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity