Arterial occlusion after cessation of warfarin treatment

Warfarin administration interferes with a wellbalanced coagulation system including coagulation factors of prothrombin and factor VII, IX and X, as well as anti-coagulation factors protein C and protein S. With discontinuation of the treatment, the coagulation system is reactivated and thromboembolic events may occur1. There is a correlation between warfarin dose compliance and therapeutic interval, bleeding risk and embolism incidence. When the estimated INR (International Normalized Ratio) is out of the therapeutic range, during the aggressive warfarin treatment, the therapeutic range should be maintained, the nonpharmacological factors should be determined and the drug effect velocity should be moderate during the drug administration; however, it is not yet fully understood how to achieve all of these. Warfarin dose fluctuation is the combination of INR, and physician’s experience and knowledge on patient’s clinical data2.Here in, we present a patient with acute arterial occlusion developing in the lower extremity after discontinuation of warfarin treatment.