Introduction and objectives: The aim of this study was to determine the prognostic value of electrocardiography in hemodynamically stable patients with a diagnosis of acute symptomatic pulmonary embolism (PE).
Methods: This prospective study included all hemodynamically stable outpatients who were diagnosed with PE at a university hospital. The electrocardiographic abnormalities investigated were: a) sinus tachycardia (>100 beats/min); b) ST-segment or T-wave abnormalities; c) right bundle branch block; d) an S1Q3T3 pattern, and e) recent-onset atrial arrhythmia.
Results: The study included 644 patients. Overall, 5% of those with an ECG abnormality died due to PE in the 15 days after diagnosis compared with 2% of those with normal ECG findings (relative risk [RR]=2.4; 95% confidence interval [CI], 1-5,8; P=.05). Multivariate analysis showed that sinus tachycardia was associated with a 2.2-fold increased risk of death due to all causes in the month after PE diagnosis. After adjusting for age, a history of cancer, immobility, ECG abnormalities, and sinus tachycardia, the presence of recent-onset atrial arrhythmia was significantly associated with death due to PE in the first 15 days (RR=2.8; 95% CI, 1-8.3; P=.05). The negative predictive value of atrial arrhythmia for 15-day PE-related mortality was 97%, while the negative likelihood ratio was 0.79.
Conclusions: In hemodynamically stable patients with acute symptomatic PE, the presence of sinus tachycardia and atrial arrhythmia were independent predictors of a poor prognosis. However, the usefulness of these factors for stratifying risk in PE patients is limited.