For this systematic review, we did an electronic search in PubMed, Google Scholar, and Embase databases to find reported cases of AHA after COVID‐19 vaccine using the keywords (either Mesh or Supplementary concept) ‐ “COVID‐19 vaccines” or “COVID‐19 vaccine booster shot” or “2019‐nCoV vaccine mRNA‐1273” or “ChAdOx1 nCoV‐19” or “BNT162 vaccine” OR “Ad26COVS1” and “Factor VIII deficiency, acquired” OR “hemophilia A, acquired” OR “hemophilia A” from inception till April, 2022. This evidence concerns the gene COX8A and COVID-19.