Pulmonary P waves (S1Q3T3 pattern + clockwise rotation) are specific for PE, but not sensitive. This study examines if an ECG can discriminate between ACS vs. PE - 40 patients with PE & 87 patients with ACS - All had negative T waves in the precordial leads (V1-V4) on the admission ECG The PE group had negative T waves commonly present in leads II, III, aVF, V1, V2, but less frequent in leads I, aVL, and V5 to V6 (p <0.05). The ACS group had negative T waves in leads III and V1 in 1% compared with 88% of patients with PE (p <0.001). Sensitivity, specificity, positive predictive value, and negative predictive value for Dx of PE were 88%, 99%, 97%, and 95%, respectively. Negative T waves in both leads III and V1 may suggest PE can be differentiated from ACS in patients with negative T waves in the precordial leads.
References
Kosuge M, Kimura K, et al. Electrocardiographic differentiation between acute pulmonary embolism and acute coronary syndromes on the basis of negative T waves. Am J Cardiol. 2007 Mar 15;99(6):817-21.
