title: Evaluation of left main coronary artery stenosis by transthoracic echocardiography.
abstract: OBJECTIVE
  We sought to demonstrate left main coronary artery (LM) stenosis by transthoracic echocardiography.
  
  
  BACKGROUND
  Evaluation of LM stenosis was done mostly by transesophageal echocardiography in patients with coronary artery disease.
  
  
  METHODS
  A total of 1456 patients with coronary artery disease were studied, of which 801 patients (55%) had adequate coronary flow assessment. The LM and the adjacent segments of left anterior descending coronary artery and left circumflex coronary artery were evaluated by color flow and Doppler. Mosaic flow and/or peak diastolic velocity of greater than or equal to 1.5 m/s was considered abnormal. These findings were correlated with stenoses at coronary angiography. A total of 40 patients who had abnormal diastolic flow in LM by transthoracic echocardiography constituted group 1 and 56 patients with normal LM flow constituted the control group (group 2).
  
  
  RESULTS
  The peak diastolic velocities in LM in group 1 ranged between 1.5 and 4.4 m/s (mean 2.11 +/- 0.78 m/s). Of the 40 patients in group 1, 34 had significant LM stenosis by coronary angiography (sensitivity of 85%, positive predictive value 82.5%). The velocities in LM in group 2 ranged between 0.4 and 1.2 m/s (mean 0.66 +/- 0.25 m/s). In all, 49 of 56 patients in this group had normal LM on coronary angiography (88% specificity, negative predictive value 90.7%). The remaining 7 had distal LM stenosis. Mosaic flow in LM indicated significant LM stenosis in 85% of patients, whereas normal flow in LM did not rule out distal LM stenosis in 12% of patients.
  
  
  CONCLUSIONS
  LM stenosis could be assessed by transthoracic echocardiography with an acceptable degree of sensitivity and specificity.
authors.affiliation: Department of Cardiology, CARE Hospital (The Institute of Medical Sciences), Hyderabad, India. anjan_anne@yahoo.com <E-mail:anjan_anne@yahoo.com>
authors.forename: Anne
authors.initials: A
authors.lastname: Anjaneyulu
authors.forename: Krishnaswamy
authors.initials: K
authors.lastname: Raghu
authors.forename: Sunehra
authors.initials: S
authors.lastname: Chandramukhi
authors.forename: Govindrao Mehetre
authors.initials: GM
authors.lastname: Satyajit
authors.forename: Srinivaskumar
authors.initials: S
authors.lastname: Arramraja
authors.forename: Penumatsa
authors.initials: P
authors.lastname: Raghavaraju
authors.forename: Penmetcha
authors.initials: P
authors.lastname: Krishnamraju
authors.forename: Bhupathiraju
authors.initials: B
authors.lastname: Somaraju
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology; D003326:Coronary Circulation / Q000502:physiology; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000503:physiopathology; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D012720:Severity of Illness Index