Diagnostic Accuracy of Early Systolic Notching in Pulmonary Embolism

Recently, a cardiac sonography finding, early systolic notching (ESN), was reported with high sensitivity and specificity for the diagnosis of pulmonary embolism (PE) in a limited population. The aim of this study was to determine the diagnostic accuracy of ESN finding for PE in emergency department (ED) patients.

This prospective multicenter study was conducted in 4 academic EDs. All patients who underwent computed tomography angiography for suspected PE were included in the study. After inclusion, cardiac ultrasound including the right ventricular outflow tract Doppler signal was performed. The diagnostic tests of ESN finding were used for PE and its subgroups.

In the study, 183 of 201 patients met the study criteria. Of all patients, 52.5% had PE (n = 96), and 19.7% (n = 36) had ESN finding. In all ED patients, the sensitivity of ESN for PE was 34% (95% CI 25-45), and the specificity was 97% (95% CI 90-99). In the subgroup analysis, the sensitivity of ESN for PE with high or intermediate-high risk was 69% (95% CI 49-85), and the specificity was 90% (95% CI 84-94). Inter-rater reliability for ESN finding between the cardiologist and emergency physician was strong with a kappa statistic of 0.87.

The pulmonary Doppler flow of ESN was moderate to high specific but low sensitive for PE in all ED patients. In the subgroup analysis, this finding was moderate specific and low sensitive.