title: Predictive Value of Exercise Stress Test-Induced ST-Segment Changes in Leads V1and avR in Determining Angiographic Coronary Involvement.
abstract: BACKGROUND
  The significance of electrocardiographic changes during exercise tolerance testing for distinguishing occluded artery is not well known. We tried to determine the role of ST elevation in leads aVR and V1during exercise in detecting stenosis of left main coronary artery and proximal left anterior descending artery.
  
  
  METHODS
  ST segment changes during exercise in 230 patients, who underwent diagnostic angiography, were documented. The association of ST elevation in lead aVR, V1, leads aVR + V1, and STE in leads aVR + V1with ST depression in other leads with pattern of coronary stenosis were investigated.
  
  
  RESULTS
  Left main and proximal left anterior artery stenosis were more common in patients with ST elevation in lead aVR (P < 0.001 for both). Similar association was found in the presence of ST elevation in lead V1. The presence of ST elevation ≥1 mm in lead aVR had a sensitivity of 100% and 94.3% for detecting left main and left anterior descending artery stenosis, respectively. The specificity was 33.5% and 26.6%, respectively. ST elevation in leads aVR + V1had a sensitivity of 74.4% and 65.9% and a specificity of 68.5% and 64.4% for detecting left main and left anterior descending arteries stenosis, respectively.
  
  
  CONCLUSIONS
  ST elevation in lead aVR is highly sensitive for left main and proximal left anterior descending artery lesions. Using ST elevation in lead V1in addition to lead aVR as a positive finding increases the specificity with a further decrease in sensitivity.
authors.affiliation: Cardiovascular Research Center, Tabriz University of Medicine, Tabriz, Iran.
authors.forename: Samad
authors.initials: S
authors.lastname: Ghaffari
authors.affiliation: Cardiovascular Research Center, Tabriz University of Medicine, Tabriz, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Asadzadeh
authors.affiliation: Cardiovascular Research Center, Tabriz University of Medicine, Tabriz, Iran.
authors.forename: Arezou
authors.initials: A
authors.lastname: Tajlil
authors.affiliation: Cardiology Department, Aalinasab Hospital, Tabriz, Iran.
authors.forename: Amirhossein
authors.initials: A
authors.lastname: Mohammadalian
authors.affiliation: Cardiovascular Research Center, Tabriz University of Medicine, Tabriz, Iran.
authors.forename: Leili
authors.initials: L
authors.lastname: Pourafkari
mesh_terms: D017023:Coronary Angiography; D023921:Coronary Stenosis / Q000175:diagnosis* / Q000503:physiopathology*; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012307:Risk Factors; D012680:Sensitivity and Specificity
keywords: coronary angiography; coronary artery disease; electrocardiography; exercise test