Monitoring Direct Thrombin Inhibitors: aPTT or Alternative?
the MPR take:
Is the activated partial thromboplastin time (aPTT) test the best for monitoring parenteral direct thrombin inhibitors? A study published in the American Journal of Clinical Pathology states that the aPTT test correlated poorly with the ecarin chromogenic assay, the prothrombinase-induced clotting time test and the dilute thrombin test when evaluating samples containing argatroban, bivalirudin and dabigatran. The best correlations were seen between the ecarin chromogenic assay and the dilute thrombin test. Further research will need to be done to see whether alternative tests are more clinically useful for monitoring parenteral direct thrombin inhibitors.
Objectives: The activated partial thromboplastin time (aPTT) test has been used for years to monitor parenteral direct thrombin inhibitors (DTIs) and unfractionated heparin. Results: The aPTT correlated poorly with each of the other tests in both bivalirudin- and argatroban-containing samples (r2 = 0.04-0.23).
READ FULL ARTICLE From ajcp.ascpjournals.org