COVID disrupts the interior lining of the blood vessels, which have the same ACE-2 receptors that SARS-COV-2 attacks. In disrupting the interior vessel walls, SARS-COV-2 causes the release into the bloodstream of von Willebrand factor, a protein that helps blood clot, which in turn leads to stroke or heart failure.
https://www.dartmouth-hitchcock.org/at-hospital/ventilator-associated_pneumonia.html
Vents are in widespread use. And they are dangerous, especially in the long term.