Prognostic Value of Right Ventricular Longitudinal Strain in Patients With COVID-19

Abstract

Objectives: The aim of this study was to investigate whether right ventricular longitudinal strain (RVLS) was independently predictive of higher mortality in patients with coronavirus disease-2019 (COVID-19).

Background: RVLS obtained from 2-dimensional speckle-tracking echocardiography has been recently demonstrated to be a more accurate and sensitive tool to estimate right ventricular (RV) function. The prognostic value of RVLS in patients with COVID-19 remains unknown.

Methods: One hundred twenty consecutive patients with COVID-19 who underwent echocardiographic examinations were enrolled in our study. Conventional RV functional parameters, including RV fractional area change, tricuspid annular plane systolic excursion, and tricuspid tissue Doppler annular velocity, were obtained. RVLS was determined using 2-dimensional speckle-tracking echocardiography. RV function was categorized in tertiles of RVLS.

Results: Compared with patients in the highest RVLS tertile, those in the lowest tertile were more likely to have higher heart rate; elevated levels of D-dimer and C-reactive protein; more high-flow oxygen and invasive mechanical ventilation therapy; higher incidence of acute heart injury, acute respiratory distress syndrome, and deep vein thrombosis; and higher mortality. After a median follow-up period of 51 days, 18 patients died. Compared with survivors, nonsurvivors displayed enlarged right heart chambers, diminished RV function, and elevated pulmonary artery systolic pressure. Male sex, acute respiratory distress syndrome, RVLS, RV fractional area change, and tricuspid annular plane systolic excursion were significant univariate predictors of higher risk for mortality (p < 0.05 for all). A Cox model using RVLS (hazard ratio: 1.33; 95% confidence interval [CI]: 1.15 to 1.53; p < 0.001; Akaike information criterion = 129; C-index = 0.89) was found to predict higher mortality more accurately than a model with RV fractional area change (Akaike information criterion = 142, C-index = 0.84) and tricuspid annular plane systolic excursion (Akaike information criterion = 144, C-index = 0.83). The best cutoff value of RVLS for prediction of outcome was -23% (AUC: 0.87; p < 0.001; sensitivity, 94.4%; specificity, 64.7%).

Conclusions: RVLS is a powerful predictor of higher mortality in patients with COVID-19. These results support the application of RVLS to identify higher risk patients with COVID-19.

Keywords: 2D, 2-dimensional; AIC, Akaike information criterion; ARDS, acute respiratory distress syndrome; CI, confidence interval; COVID-19; COVID-19, coronavirus disease-2019; HR, hazard ratio; LS, longitudinal strain; LV, left ventricular; LVEF, left ventricular ejection fraction; PASP, pulmonary artery systolic pressure; ROC, receiver-operating characteristic; RV, right ventricular; RVFAC, right ventricular fractional area change; RVLS, right ventricular longitudinal strain; SARS-CoV-2; SARS-CoV-2, severe acute respiratory syndrome-coronavirus-2; STE, speckle-tracking echocardiography; S’, tricuspid lateral annular systolic velocity; TAPSE, tricuspid annular plane systolic excursion; TR, tricuspid regurgitation; right ventricular function; speckle tracking echocardiography; strain.

Graphical abstract

Figure 1

RVLS Obtained From 2-Dimensional Speckle Tracking Echocardiography in Patients With COVID-19 (A) Representative images of the highest tertile of right ventricular longitudinal strain (RVLS). (B) Representative images of the middle tertile of RVLS. (C) Representative images of the lowest tertile of RVLS.

Figure 2

Distribution of RVLS in Patients With COVID-19 (A) Distribution of right ventricular longitudinal strain (RVLS) in patients with coronavirus disease-2019 (COVID-19) (blue, highest tertile; green, middle tertile; red, lowest tertile). (B) Tukey box-and-whisker plots of RVLS values in patients with COVID-19 according to the tertiles. (C) Distribution of RVLS in patients with COVID-19 (red) and healthy control subjects (green). RVLS values are absolute values.

Figure 3

Receiver-Operating Characteristic Curves of RVLS, FAC, and TAPSE for Adverse Clinical Outcome FAC = fractional area change; RVLS = right ventricular longitudinal strain; TAPSE = tricuspid annular plane systolic excursion.

Figure 4

Kaplan-Meier Survival Curves Showing the Association of Higher Mortality and Right Ventricular Function (A) Kaplan-Meier curve of survival in patients stratified by the cutoff value of tricuspid annular plane systolic excursion (TAPSE). (B) Kaplan-Meier curve of survival in patients stratified by the cutoff value of right ventricular fractional area change (FAC).

Central Illustration

Association of Right Ventricular Longitudinal Strain and Mortality in Patients With COVID-19 In the upper panel, examples of strain plot of right ventricular longitudinal strain (RVLS) are shown: (A) a 42-year-old patient with impaired RVLS (16.8%), who died of coronavirus disease-2019 17 days after the echocardiographic examination; and (B) a 57-year-old patient with preserved RVLS (29.3%), who did not experience an event during 61 days of follow-up. In the lower panel, survival curves for all-cause mortality are shown (C) according to the cutoff value of RVLS (23%) and (D) according to tertiles of RVLS (≤20.5%, 20.6% to 25.4%, and ≥25.5%). RVLS values are absolute values.