Here is a recent question from a colleague. "Dear George, A patient with a PE of unknown etiology, is now completing their 6th month of Eliquis therapy. When is the ideal time to check a D-dimer? Thank you."
Before answering, I [Geo] consulted with Dr. Larry Brace, who responds, "My opinion is that if the patient has been completely asymptomatic for the 6 months on Eliquis, a normal D-D at this point is a good indication of effectiveness of the treatment [given all the usual demographics of age, sex, ethnicity, etc]. Elevated D-D is a good indicator of reccurnce risk: the higher the D-D , the higher the risk of thrombosis recurrence. This is sometimes used to adjust the aggressiveness of therapy."
Meanwhile, I've seen no reference that indicates how long the interval should be between when the Eliquis is discontinued and when the D-dimer should be collected, so I'll just post an opinion and look for confirmation from our participants. I suggest waiting at least five days after the therapy is ended to ensure all coagulation factors are present in normal activity levels and thus fibrinolysis will be minimal. However, remember that any inflammatory condition raises the D-dimer level, so the patient should be in good health at the time the D-dimer is collected. If the D-dimer is elevated, many physicians choose to continue therapy for an addtional time period, then test again.