Considering these limitations, our review article proposes some hypotheses for the HIF and COVID-19 issue: (1) Perhaps the sequelae observed in PACS are strongly linked to the prolonged action of HIF during the process of prolonged hypoxia, and this prolonged activation of HIF may be influencing the formation of new closed-bottom blood vessels (through VEGF), which have blood in a state of hypercoagulability, preparing for the formation of microthrombi. Here, VEGFA is linked to COVID-19.