ECG Score Predicts Those With the Greatest Percentage of Perfusion Defects Due to Acute Pulmonary Thromboembolic Disease

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 ˙ /Qscan findings were categorized into those with 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 ) and V ˙ /Qscore was 0.55 (). The ECG predicted those with the greatest amount of perfusion defects. Mean ECG score was 2.6 (SD 2.8) in patients with 50% perfusion defect. The area under the receiver operating character- istic curve for ECG score and those with > 50% perfusion defect was 0.71 (SE 0.04). An ECG score of > 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%). Conclusion: An ECG score, simple to derive, predicts those with the greatest percentage of perfusion defect. Using the ECG for management warrants prospective evaluation. (CHEST 2004; 125:1651-1656)