Follow-up assessment of the microvascular function in patients with long COVID, 2025, Romanowska-Kocejko et al.

Follow-up assessment of the microvascular function in patients with long COVID
Romanowska-Kocejko; Braczko; Jędrzejewska; Żarczyńska-Buchowiecka; Kocejko; Kutryb-Zając; Hellmann

Long COVID is a complex pathophysiological condition. However, accumulating data suggests that COVID-19 is a systemic microvascular endothelial dysfunction with different clinical manifestations.

In this study, a microvascular function was assessed in long COVID patients (n = 33) and healthy controls (n = 30) using flow-mediated skin fluorescence technique (FMSF), based on measurements of nicotinamide adenine dinucleotide fluorescence intensity during brachial artery occlusion (ischemic response, IR) and immediately after occlusion (hyperemic response, HR). Microcirculatory function readings were taken twice, 3 months apart. In addition, we quantified biochemical markers such as the serum L-arginine derivatives and hypoxia-inducible factor 1α (HIF1α) to assess their relation with microvascular parameters evaluated in vivo.

In patients with long COVID, serum HIF1α was significantly correlated to IRindex (r = −0.375, p < 0.05). Similarly, there was a significant inverse correlation of serum asymmetric dimethyl-L-arginine levels to both HRmax (r = −0.343, p < 0.05) and HRindex (r = −0.335, p < 0.05). The IR parameters were found lower or negative in long COVID patients and recovered in three-month follow-up. Hypoxia sensitivity value was significantly higher in long COVID patients examined after three months of treatment based on the combination of ACE-inhibitors and beta-adrenolytic compared to baseline condition (85.2 ± 73.8 vs. 39.9 ± 51.7 respectively, p = 0.009).

This study provides evidence that FMSF is a sensitive, non-invasive technique to track changes in microvascular function that was impaired in long COVID and recovered after 3 months, especially in patients receiving a cardioprotective therapy.

Highlights
• FMSF is a sensitive technique to track changes in the microvascular function in long COVID.

• FMSF parameters are associated with biochemical endothelial markers showing altered endothelial function after SARS-CoV-2 infection.

• Cardioprotective therapy improve microvascular function in long COVID patients.

Link (Microvascular Research)

 

Follow on from Red Blood Cell Adenylate Energetics Is Related to Endothelial and Microvascular Function in Long COVID (2024, Biomedicines)