title: Value of lead aVR in the detection of significant left main coronary artery stenosis in acute coronary syndrome.
abstract: BACKGROUND
  Electrocardiographic lead aVR is usually ignored in patients with chest pain. ST segment elevation in aVR may have diagnostic value in patients with acute coronary syndrome (ACS) and significant stenosis or obstruction of the left main coronary artery (LMCAS), especially when accompanied by ST segment elevation in lead V(1).
  
  
  OBJECTIVE
  To asses the value of lead aVR and V1 for the detection of LMCAS in patients with ACS.
  
  
  METHODS
  The study group consisted of 150 patients (mean age 60.6+/-9.5 years, range 33-78 years) with ACS, including 46 with LMCAS and 104 without LMCAS. ECG recordings obtained on admission were compared between these two groups.
  
  
  RESULTS
  In patients with LMCAS, ST segment elevation in lead aVR was two times more frequent than in remaining patients (69.6% vs 34.6% p=0.0001) whereas there were no differences in lead V(1). Sensitivity of ST elevation in aVR in detection of LMCAS was 69.6%, specificity - 65.4%, positive predictive value - 47.1%, and negative predictive value - 82.9%. In patients with LMCAS, ST segment depression was significantly more often present in ECG leads other than aVR (45.6% vs 23.1% p<0.01). Patients with LMCAS more often had hypertension (95.6% vs 77.9% p<0.05) and three-vessel disease (78.3% vs 31.8%, p<0.0001).
  
  
  CONCLUSIONS
  The assessment of lead aVR in patients with ACS may indicate LMCAS. Additional analysis of lead V(1) does not improve diagnostic accuracy.
authors.affiliation: Department of Coronary Artery Disease, Institute of Cardiology, Collegium Medicum, Jagiellonian University, John Paul the 2nd Hospital, Cracow, Poland.
authors.forename: Paweł
authors.initials: P
authors.lastname: Rostoff
authors.forename: Wiesława
authors.initials: W
authors.lastname: Piwowarska
authors.forename: Ewa
authors.initials: E
authors.lastname: Konduracka
authors.forename: Anna
authors.initials: A
authors.lastname: Libionka
authors.forename: Marzena
authors.initials: M
authors.lastname: Bobrowska-Juszczuk
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Stopyra
authors.forename: Andrzej
authors.initials: A
authors.lastname: Gackowski
authors.forename: Aleksander
authors.initials: A
authors.lastname: Kubinyi
authors.forename: Bohdan
authors.initials: B
authors.lastname: Nessler
authors.forename: Danuta
authors.initials: D
authors.lastname: Mroczek-Czernecka
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D023921:Coronary Stenosis / Q000175:diagnosis* / Q000503:physiopathology; D003331:Coronary Vessels / Q000473:pathology* / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity