Thrombocytopenia. This can be brought on by exposure to blood thinners, e.g., heparin-induced thrombocytopenia (HIT). They used heparin during my open-heart surgery and I wound up with 3 clots (2 in lung, 1 in leg) before they discovered I had HIT. i was in the hospital for 19 days recuperating to get over the anemia resulting from the clots (if red blood cells are used up in clots, you have anemia). Therefore, I conclude the vaccine would be a death sentence for me.