Right-sided Electrocardiogram in Patients With Acute Pulmonary Embolism

Abstract

Background: Acute pulmonary embolism (APE) is an emergent condition. The diagnostic tools are CT angiography and echocardiography. However, all of these modalities can be used under stable and nonemergent conditions. As electrocardiographic (ECG) studies are more feasible under emergent situations, Objective: we aimed to study right-sided ECG (RS-ECG) in patients with APE with further analysis regarding echocardiographic findings and pulmonary embolism severity index (PESI). Methods: Right-sided and standard electrocardiogram were obtained from 143 patients with confirmed APE. T-wave inversion, ST segment elevation (STE), and QS pattern in RS-ECG have been considered as abnormal changes. Results: T-wave inversion, STE, and QS pattern were found in 78.3%, 42%, and 39.9% of patients, respectively. 88.1% of patients showed at least one of these abnormalities in their RS-ECGs. Sensitivity of RS-ECG for APE was 0.88, which was higher than sensitivity of standard ECG (0.79). Patients with STE in right precordial leads, had increased right to left ventricular (RV/LV) diameter ratio (P = 0.021) and had higher PESI score (P = 0.000). Moreover, STE in RS-ECG was an independent predictor for PESI score in patients with moderate (odds ratio 4.05; 95% confidence interval [CI], 1.37-11.96; P < 0.05) and high 30-day mortality risk (odds ratio 8.42; 95% CI, 2.08-33.93; P < 0.05). Conclusions: Abnormal changes in RS-ECG were associated with an increase in RV/LV diameter ratio and higher PESI score, which may be indicated poor prognosis in patients with APE. The most clinically useful ECG finding was STE which was associated with increased RV/LV diameter ratio and PESI score.