title: ECG score predicts those with the greatest percentage of perfusion defects due to acute pulmonary thromboembolic disease.
abstract: BACKGROUND
  More aggressive management may be warranted for patients with acute pulmonary embolism (PE) and the greatest pulmonary vascular obstruction. We hypothesized that a scoring system based on the ECG might identify such patients.
  
  
  METHODS
  Consecutive patients investigated for PE at Christchurch Hospital between 1997 and 2002 with high-probability ventilation/perfusion (V/Q) scan findings were studied. The ECG obtained closest to and within 48 h of the scan was scored by two independent observers, and the mean ECG score was calculated. V/Q scan findings were categorized into those with < 30%, 30 to 50%, and > 50% perfusion defect by two independent observers experienced in V/Q interpretation. A consensus score was taken when disagreement occurred.
  
  
  RESULTS
  Two hundred twenty-nine patients were included in the study. The interobserver agreement for ECG score was 0.96 (Cronbach alpha) and V/Q score was 0.55 (kappa). The ECG predicted those with the greatest amount of perfusion defects. Mean ECG score was 2.6 (SD 2.8) in patients with < 30% perfusion defect, 3.2 (SD 2.9) in patients with 30 to 50% perfusion defect, and 5.3 (SD 3.7) in patients with > 50% perfusion defect. The area under the receiver operating characteristic curve for ECG score and those with > 50% perfusion defect was 0.71 (SE 0.04). An ECG score of > or = 3 predicted those with > 50% perfusion defect with a sensitivity of 70% (95% confidence interval [CI], 59 to 81%), and a specificity of 59% (95% CI, 51 to 67%).
  
  
  CONCLUSIONS
  An ECG score, simple to derive, predicts those with the greatest percentage of perfusion defect. Using the ECG for management warrants prospective evaluation.
authors.affiliation: Canterbury Respiratory Research Group, Christchurch School of Medicine and Health Sciences, University of Otago, New Zealand. steveiles@doctors.org.uk
authors.forename: Stephen
authors.initials: S
authors.lastname: Iles
authors.forename: Campbell J
authors.initials: CJ
authors.lastname: Le Heron
authors.forename: Gwyn
authors.initials: G
authors.lastname: Davies
authors.forename: John G
authors.initials: JG
authors.lastname: Turner
authors.forename: Lutz E L
authors.initials: LE
authors.lastname: Beckert
mesh_terms: D000208:Acute Disease; D000368:Aged; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011652:Pulmonary Circulation; D011655:Pulmonary Embolism / Q000503:physiopathology*; D012720:Severity of Illness Index