It looks like the Thing from Another World. Did they pull that out of an artery?
This would make a very cool sci fi movie: someone who got vaxxed for COVID then developed these sentient critters in their major blood vessels. The host no longer needed, the poor vaxxed person dies and the icky thing in the picture opens some unworldly EYES, looking right at the audience. Then it exudes some limbs and makes it way over to one of the labs producing the vax and insinuates eggs or spores from itself into the latest batch...