The Predictive Role of Combined Cardiac and Lung Ultrasound in Coronavirus Disease 2019

Abstract

Background: The aim of this study was to evaluate sonographic features that may aid in risk stratification and to propose a focused cardiac and lung ultrasound (LUS) algorithm in patients with coronavirus disease 2019.

Methods: Two hundred consecutive hospitalized patients with coronavirus disease 2019 underwent comprehensive clinical and echocardiographic examination, as well as LUS, irrespective of clinical indication, within 24 hours of admission as part of a prospective predefined protocol. Assessment included calculation of the modified early warning score (MEWS), left ventricular systolic and diastolic function, hemodynamic and right ventricular assessment, and a calculated LUS score. Outcome analysis was performed to identify echocardiographic and LUS predictors of mortality or the composite event of mortality or need for invasive mechanical ventilation and to assess their adjunctive value on top of clinical parameters and MEWS.

Results: A simplified echocardiographic risk score composed of left ventricular ejection fraction < 50% combined with tricuspid annular plane systolic excursion < 18 mm was associated with mortality (P = .0002) and with the composite event (P = .0001). Stepwise analyses evaluating echocardiographic and LUS parameters on top of existing clinical risk scores showed that addition of tricuspid annular plane systolic excursion and stroke volume index improved prediction of mortality when added to clinical variables but not when added to MEWS. Once echocardiography was added, and patients were recategorized as high risk only if having both high-risk MEWS and high-risk cardiac features, specificity increased from 63% to 87%, positive predictive value from 28% to 48%, and accuracy from 66% to 85%. Although LUS was not associated with incremental risk prediction for mortality above clinical and echocardiographic criteria, it improved prediction of need for invasive mechanical ventilation.

Conclusions: In hospitalized patients with coronavirus disease 2019, a very limited echocardiographic examination is sufficient for outcome prediction. The addition of echocardiography in patients with high-risk MEWS decreases the rate of falsely identifying patients as high risk to die and may improve resource allocation in case of high patient load.

Keywords: COVID-19; Echocardiography; FoCUS; Lung ultrasound; Risk stratification.