Long term non-invasive endothelial function assessment in patients with paediatric inflammatory multisystem syndrome temporarily associated with Covid 19 (PIMS TS)

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Patients with PIMS-TS present with features of vasculitis (bright coronary arteries and diffuse coronary ectasia on transthoracic echocardiography) and prothrombotic features (e.g. elevated D Dimers) indicating involvement of the endothelial layer in the inflammatory process. Impairment in endothelial function may contribute to the acute but also to possible long-term consequences in patients with PIMS-TS. The aim of this pilot study is to assess non-invasively the endothelial (dys)function using reactive hyperemic peripheral arterial tonometry (RH-PAT) 6 months after the acute inflammatory phase. Methods Ten patients with previous diagnosis of PIMS-TS were compared to age-matched controls. The endothelial function was assessed using the EndoPAT device which provides the reactive hyperemic index (RHI) of endothelial function in a 15-min test. Cardiac function indices by means of LV fractional shortening (FS) was also assessed. Results There were no significant differences regarding age (11.2 ± 3.0 vs 13.6 ± 2.4, p = 0.063), height, weight and body surface area, (BSA: 1.49 ± 0.36 vs 1.52 ± 0.25, p = 0.856) in patients with previous diagnosis of PIMS-TS and controls respectively. The two groups also had similar LV systolic function assessed by FS (36.3 ± 9.1% vs 36.7 ± 7.1%, p = 0.922). The RHI in the PIMS TS group was similar to the control group (1.65 ± 0.43 vs 1.81 ± 0.60, p = 0.533 respectively). Conclusions. Patients with PIMS-TS who may present with features of vasculitis during the acute phase, do not show evidence of endothelial dysfunction during the long term follow-up, suggesting resolution. Further studies are required to accurately determine the endothelial (dys)function during the acute phase of the inflammatory syndrome and course.