Utility of the Right Ventricular Early Inflow-Out Flow Index in the Assessment of Mortality in COVID-19

Background: The coronavirus disease 2019 (COVID-19) outbreak continues to spread worldwide, hence the increasing attention to the predictors of mortality. However, there is no easy prognostic risk score to predict in-hospital mortality. We aimed to assess the efficacy of the right ventricular early inflow-outflow index (RVEIO) as a predictor of early mortality in patients with thromboembolism. Additionally, we assessed acute respiratory distress syndrome, which is deemed a complication of COVID-19 and an etiology of acute cor pulmonale. Methods: This single-center, observational cross-sectional study assessed laboratory data and electrocardiographic and echocardiographic findings of patients with a diagnosis of COVID-19 based on a positive polymerase chain reaction test and lung involvement exceeding 20% in the non-intensive care units of our hospital. Results: The study population comprised 360 patients (mean age=54.46 y, 61.1% male). The mean RVEIO index was 3.40 ± 1.14, the mean right ventricular peak systolic myocardial velocity (RVsm) was 12.29 ± 3.81 cm/s, and the mean tricuspid annular plane systolic excursion (TAPSE) was 22.41 ± 4.97 cm. No significant difference was found in the RVEIO index between the patients who were discharged and those who expired (3.26 ± 1.25 vs 3.31 ± 1.29, respectively), nor was there a correlation between the RVEIO index and admission to the intensive care unit. The RVEIO index was not a predictor of RV dysfunction, as assessed by RVsm and TAPSE. Patients who suffered from myocardial infarction had a significantly higher RVEIO index. Conclusions: None of the echocardiographic findings, including the RVEIO index, was an accurate predictor of RV dysfunction, mortality, and inflammation levels in our patients with COVID-19. Accordingly, they should not be relied upon for clinical decision-making and management.