Future directions
Although the routine monitorings of the plasma concentrations of NOACs and the anti-factor Xa activities are generally not necessary in the daily practice, the plasma concentrations of NOACs haven been shown significantly associated with bleeding and ischemic events.54,55If the measurements of plama concentrations of NOACs were available in the institutions caring the COVID-19 infected patients, the monitoring of plasma levels of NOACs may be considered when drug-drug interactions between NOACs and medications for COVID-19 are concerned. More clinical experiences are necessary for the concomitant use of OACs and COVID-19 therapies.