Association Between Electrocardiographic Findings, Right Heart Strain, and Short‐Term Adverse Clinical Events in Patients With Acute Pulmonary Embolism

BACKGROUND: Electrocardiographic (ECG) changes may be seen with pulmonary emboli (PE). Whether ECG is associated with short-term adverse clinical events after PE is less well established. HYPOTHESIS: ECG findings are associated with short-term clinical deterioration after PE. METHODS: Consecutive adult PE patients were enrolled in an academic emergency department from 2008 to 2011. The primary outcome was right heart strain (RHS) on echocardiogram or CT pulmonary angiography, or TnT ≥0.1 ng/mL. We derived an ECG (TwiST) score that is associated with RHS and short-term adverse clinical events. RESULTS: We enrolled 298 patients with PE. On multivariate analysis, T-wave inversion in leads V(1) through V(3) (OR: 4.7, 95% confidence interval [CI]: 1.7-13.2), S wave in lead I (OR: 2.0, 95% CI: 1.1-3.5), and tachycardia (OR: 2.5, 95% CI: 1.3-4.8) were associated with RHS. A TwiST score ≤2 (n = 210, 72%) was 84% (95% CI: 77%-90%) sensitive for the absence of RHS, whereas a TwiST score ≥5 (n = 47, 16%) was 93% (95% CI: 88%-97%) specific for the presence of RHS. CONCLUSIONS: A simple ECG (TwiST) score can identify patients likely or not likely to have RHS with >80% specificity and sensitivity and may assist in identifying patients with acute PE at risk for adverse clinical events before pursuing other advanced imaging tests.