Hypercoagulation Detected by Rotational Thromboelastometry Predicts Mortality in COVID-19: A Risk Model Based on a Prospective Observational Study

ABSTRACT Background: Severe disease due to COVID-19 has been shown to be associated with hypercoagulation. The aim of this study was to assess Rotational Thromboelastometry (ROTEM®) as a marker of coagulopathy in hospitalized COVID-19 patients. Methods: This was a prospective, observational study where patients hospitalized due to a COVID-19 infection were eligible for inclusion. Conventional coagulation tests and ROTEM were taken after hospital admission, and patients were followed for 30 days. A prediction model including variables ROTEM EXTEM-MCF (Maximum Clot Firmness), which in previous data has been suggested a suitable marker of hypercoagulation, age and respiratory frequency was developed using logistic regression to evaluate the probability of death. Results: Out of the 141 patients included, 18 (13%) died within 30 days. In the final prediction model, the risk of death within 30 days for a patient hospitalized due to COVID-19 was increased with increased EXTEM-MCF, age and respiratory frequency. Longitudinal ROTEM data in the severely ill subpopulation showed enhanced hypercoagulation. In an in vitro analysis, no heparin effect on EXTEM-CT (Coagulation Time) was observed, supporting a SARS-CoV-2 effect on prolonged initiation of coagulation. Conclusions: Here we show that hypercoagulation measured with ROTEM predicts 30-days mortality in COVID-19. Longitudinal ROTEM data strengthen the hypothesis of hypercoagulation as a driver of severe disease in COVID-19. Thus, ROTEM may be a useful tool to assess disease severity in COVID-19 and could potentially guide anticoagulation therapy.