From a US standpoint I agree with everything here. Is it worth having a malpractice lawyer look at this? Yes. Is there a clear delay between stroke identification and likely onset? Yes, it sounds like it. Is there clear harm done? Not necessarily. Im so sorry all this happened, OP. Its hard even if there is no mistreatment.
I'm unsure on which valve was replaced, I've honestly never thought to enquire. The bleeding wasn't really all that significant, at least that I saw, my father wasn't complaining of being in any pain either and originally I was told that bleeding without pain shouldn't be a concern - it was only when I noticed he was passing clots into his catheter bag that I was told to get him to hospital.They 100% stopped the enoxaparin but I'm not totally sure about the aspirin.Edit: after checking with family we believe it was an aortic valve replacement