Assessing the severity of pulmonary embolism among patients in the emergency department: Utility of RV/LV diameter ratio

BACKGROUND: Acute pulmonary embolism (APE) is a major cause of death from cardiovascular disease. Right ventricular systolic dysfunction (RVD) caused by APE is closely related to a poor outcome. Early risk stratification of APE is a vital step in prognostic assessment. The objective of this study was to investigate the usefulness of computed tomographic pulmonary angiography (CTPA) measured right ventricular (RV)/ left ventricular (LV) diameter ratio by the emergency department (ED) specialists for early risk stratification of APE patients in ED. METHODS: The retrospective data of 229 APE patients were reviewed. Two ED specialists measured both RV and LV diameters on a single transverse scan perpendicular to the long axis of the heart. The patients were divided into two groups, RV/LV diameter ratio <1 and ratio >1. CTPA measured RV/LV diameter ratio were analyzed and compared with sPESI score, cardiac biomarkers such as N-Terminal Pro-B-Type Natriuretic Peptide (NT-pro-BNP), high sensitivity cardiac troponin T (hs-cTnT), and RVD measured by echocardiography (Echo). RESULTS: The mean age in RV/LV > 1 group was significantly higher than that of the other group (67.81±2.7 years vs. 60.68±3.2 years). Also, there were more hypertension patients (44.4% vs. 33.3%), and mean arterial pressure (MAP) was lower. A significantly higher ICU admission rate (28.05% vs. 11.61%) was shown in RV/LV >1 group, and five patients expired only in RV/LV > 1 group. RVD by Echo demonstrated the highest sensitivity, specificity, and negative predictive value (NPV) (values of 94.3%, 81.1%, 95.5%). RV/LV >1 diameter ratio by CTPA showed usefulness equivalent to cardiac biomarkers. RV/LV >1 patients’ cardiac enzymes were higher, and there were more RVD in RV/LV >1 group. CONCLUSION: Simple measurement of RV/LV diameter ratio by ED specialist would be a help to the clinicians in identifying and stratifying the risk of the APE patients presenting in the ED.