Abstract
The development of COVID-19 syndrome in anticoagulated patients, and especially their admission to intensive-care units with acute severe respiratory syndrome (SARS-CoV-2), expose them to specific problems related to their therapy, in addition to those associated with the acute viral infection. Patients on VKA hospitalized with SARS-CoV-2 show high instability of PT INR due to the variability of vitamin K metabolism, diet, fasting, co-medications, liver impairment, and heart failure. Patients on DOAC are exposed to under/over treatment caused by significant pharmacological interferences. In consideration of the pharmacological characteristics of oral anticoagulant drugs, the multiple pharmacological interactions due to the treatment of acute disease and the possible necessity of mechanical ventilation with hospitalization in intensive-care units, we suggest replacing oral anticoagulant therapies (VKA and DOAC) with parenteral heparin to avoid the risk of over/under treatment.