For those interested in latest research, Dr. Bhupesh Prusty presented[2] a very plausible hypothesis with detailed evidence[3] of virus-triggered autoimmunity causing mitochondrial dysfunction in endothelial cells (vascular system).
And there's a promising treatment for Long COVID with a study[4] claiming improvement in many symptoms, and describing the targeted mechanism of disease pathology (also vascular system). Needs trials and replication, or until then doctors willing to risk off-label treatment.
[0] https://web.archive.org/web/20230728074923/https://www.theat...
[1] https://web.archive.org/web/20230731145624/https://www.theat...
[2] https://www.youtube.com/watch?v=sBmtnMenHgw
[3] https://www.medrxiv.org/content/10.1101/2023.06.23.23291827v...