Aortic Aneurysm-associated Disseminated Intravascular Coagulation that Responded Well to a Switch from Warfarin to Rivaroxaban.

We describe a case in which uncontrolled chronic disseminated intravascular coagulation (DIC) caused by an aortic aneurysm that was exacerbated by chemotherapy for lung cancer, showed dramatic improvement when warfarin, which was being administered for atrial fibrillation, was replaced by rivaroxaban, a direct oral anticoagulant (DOAC). The present case is interesting because a DOAC was effective in treating DIC due to an aortic aneurysm, whereas warfarin, another oral anticoagulant, was ineffective. In controlling DIC, it is important to inhibit activated coagulation factors such as thrombin and activated factor X, rather than the coagulation factors, which act as substrates.