The impact of long COVID on myocardial work performance
Authors: Luchian M L , Motoc A , Roosens B , Magne J , Van Den Bussche K , Chameleva H , De Potter T , Houard L , Droogmans S , Cosyns B 
Published: October 2022

Abstract

Background
Long COVID emerged as a new condition, following the acute episode of coronavirus disease 2019 (COVID-19),exerting a significant impact on patients' quality of life [1]. Several studies involving COVID-19 survivors emphasized the presence of cardiac abnormalities following the acute infection. However, data on possible mechanisms associated to long COVID remain limited. Clinical applications of myocardial work (MW) analysis, assessed by transthoracic echocardiography (TTE) have expended recently, showing an additional value in detecting cardiac dysfunction compared to standard parameters such as left ventricle ejection fraction (LVEF) or global longitudinal strain (GLS) in various pathologies, including COVID-19 [2]. Nevertheless, its potential role in detecting subclinical cardiac dysfunction in long COVID remained unexplored.

Purpose
We assessed the association between subclinical cardiac dysfunction evaluated by global work index (GWI) and global constructive work (GCW) and long COVID.

Methods
We included 310 COVID-19 patients hospitalized between March and April 2020. All patients were invited to a systematic one-year follow-up, including clinical evaluation, TTE with MW assessment, chest-computed tomography and spirometry. 140 patients completed the follow-up. Normal values for GWI and GCW were defined as 1926±247 mmHg% and 2224±229 mmHg% [3]. The primary endpoint was long COVID, characterized by a cluster of symptoms such as fatigue or dyspnea more than 3 months after the acute infection, without any other explanation.

Results
140 patients (57.1±13.9 years, 90 (64.3%) males) had a mean follow-up of 337.1±34.5 days.The mean values of LVEF, GWI and GCW were 55.2±3.2%, 2105.9±403.3 mmHg% and 2377.8±446.2 mmHg%. 83 (61%) patients had long COVID. No significant differences in terms of comorbidities, clinical evaluation and COVID-19 severity were found between patients with and without long COVID. GCW (2276.7±410.3 vs 2516.5±458.6, p=0.006) and GWI (2008.5±358.9 vs 2242.2±427.0, p=0.003) were the only TTE parameters different between patients with and without long COVID. Multivariable regression analysis showed that GWI &lt;1926 mmHg% (OR 6.095; CI: 2.024–18.355, p=0.001) and GCW &lt;2224 mmHg% (OR 3.205; CI: 1.181–8.694, p=0.022) were the only MW parameters independently associated with long COVID, irrespective of age or the severity of the acute infection, at one year. In a subgroup analysis of 77 patients without previous cardiovascular diseases, long COVID was diagnosed in 45 (58.4%)patients. GWI &lt;1926 mmHg% (OR 8.015; CI: 2.149–29.887, p=0.002) remained independently associated with long COVID at 1 year follow-up.

Conclusions
Long COVID, frequently observed in recovered COVID-19 patients may indicate the presence of subclinical cardiac dysfunction, reflected by a decrease of the left ventricle performance, assessed by GWI and GCW.Long-term follow-up including cardiac screening should be performed in order to identify patients at risk who would benefit from cardiac rehabilitation programs.

Funding Acknowledgement
Type of funding sources: None.