Monitoring DOACs with a Novel Dielectric Microsensor: A Clinical Study
Over the past decade, direct oral anticoagulants (DOACs) have been steadily complementing
and replacing vitamin K antagonists for prevention and treatment of venous thrombosis
as well as for the management of non-valvular atrial fibrillation, particularly in
suitable subgroups.[1]
[2] Despite the considerable advantages of DOACs, their metabolism is complex and assessment
of DOAC anticoagulant effects may be useful in several situations. Conventional clotting
time assays performed in diagnostic laboratories including the prothrombin time and
activated partial thromboplastin time capture the anticoagulant effect of DOACs with
variable sensitivity and cannot reliably predict clinically meaningful DOAC levels.
In contrast, drug-specific anti-Xa assays and liquid chromatography mass spectroscopy
are extremely precise and sensitive, but their use is limited to central laboratories
and results are not rapidly available.
In this issue of Thrombosis and Haemostasis, Maji et al[3] describe a novel point-of-care diagnostic device termed ClotChip, which utilizes
the electrical technique of dielectric spectroscopy to assess whole blood coagulation
ex vivo. This novel assay allows predicting DOAC response within 30 minutes using
only 10 μL of whole blood. In this pilot study, the authors demonstrated that ClotChip
could reliably detect the anticoagulant effects of rivaroxaban, apixaban, and dabigatran
with improved sensitivity over routine coagulation tests. This novel point-of-care
device is cheap to manufacture and does not require special equipment or reagents,
making ClotChip a cost-effective means to monitor the efficacy of DOACs under various
clinical scenarios in a single, disposable cartridge. Anticoagulation therapy often
entails time-critical decisions. Such an onsite analyzer of patients' hemostatic ability,
addresses a currently unmet need and could potentially shift the current care of patients
with DOAC-related emergencies and beyond.
