Subclinical left ventricular dysfunction detected by speckle tracking echocardiography predicts mortality in COVID-19 patients
Authors: Cwiek-Rebowska E , Filipiak-Strzecka D , Cygulska K , Szymczyk E , Wdowiak-Okrojek K , Wejner-Mik P , Miskowiec D , Kasprzak J D , Lipiec P 
Published: October 2024

Abstract
In COVID-19 patients, both preexisting cardiovascular disease and cardiac injury resulting from SARS-CoV-2 infection are associated with increased mortality. In this patient population the value of speckle tracking echocardiography (STE) for detecting high-risk patients has not been evaluated thoroughly.

Aim
The aim of study was to determine the prevalence of subclinical myocardial dysfunction revealed by STE and its association with in-hospital and two-year mortality in patients with COVID-19 and preserved left ventricular ejection fraction (LVEF).

Methods
The study group comprised 163 consecutive patients with preserved LVEF(&gt;/=50%) and maintained right ventricular function evaluated by assessment of tricuspid annular plane systolic excursion (TAPSE &gt;14 mm) hospitalized in the cardiology department due to COVID-19 in 2020 and 2021. All patients underwent transthoracic echocardiographic examination with off-line analysis using STE. Left ventricular global longitudinal strain(GLS), right ventricular global longitudinal strain (RV-GLS), right ventricular free wall strain(RV-FWS) and myocardial work parameters: global work index(GWI), global wasted work(GWW), global constructive work(GCW) and global work efficiency(GWE) were measured. The primary outcome was in-hospital and two-year mortality.

Results
96 patients (mean age 66 years, 59 [61%] male) had adequate image quality to evaluate deformation-derived parameters.19 patients (19.8%) died during hospitalization and 9 (9,4%) patients died within two years after discharge. In-hospital non-survivors were older, had lower baseline oxygen saturation(SpO2) and had higher NTproBNP. In non-survivors STE revealed significant impairment of LV and RV function compared to the group of survivors(Table 1).
The independent predictors of in-hospital death were: age (OR 1.1 [95% CI 1.01 – 1.19]), SpO2 on admission (OR 0.83 [95% CI 0.75 – 0.93]), NTproBNP (OR 1.0003 [95% CI 1.0001 – 1.0006]) and LV-GLS (OR 1.45 (1.06 – 1.99)]. Based on the analysis of the ROC curves, the cut-off points optimal for predicting in-hospital death were identified: age &gt;71 years (sensitivity [sens.] 74%, specificity [spec.] 68%) , baseline SpO2 value ≤ 89% (sens. 89%, spec. 74%,) NTproBNP &gt;951 pg/ml (sens. 79%, spec. 58%) and GLS &gt;-16% (sens. 63%, spec. 89%).
The independent predictors of two-year mortality were: age (OR 1.10 [95% CI 1.02 – 1.19]), Sp02 on admission (OR 0.82 [95% CI 0.73 – 0.91]) and NTproBNP (OR 1.0006 [95% CI 1.0001 – 1.0011]).Based on the ROC curve analysis, the cut-off points optimal for predicting death within 24 months after COVID-19 were also identified: age&gt;71 years (sens. 71%; spec. 72%), Sp02 &lt;89% (sens. 69%, spec. 73%), NTproBNP &gt;520 pg/ml (sens. 89%, spec. 48%).

Conclusions
STE allows for the detection of subclinical myocardial dysfunction in COVID-19 patients with preserved LVEF. However, LV GLS is the only independent STE-based predictor of in-hospital mortality in this patient population.