Atrial fibrillation and heart valve disease: self-monitoring coagulation status using point-of-care coagulometers (the CoaguChek XS system)

2 Current practice

Many conditions can result in people having an increased risk of thrombosis, and consequently having long‑term oral anticoagulant therapy. These include atrial fibrillation and heart valve disease.

NICE's guideline on atrial fibrillation recommends offering anticoagulation therapy (apixaban, dabigatran etexilate, rivaroxaban or a vitamin K antagonist) to men with a CHA2DS2-VASc score of 1 and to people with a CHA2DS2-VASc score of 2 or above, taking bleeding risk into account, as an intervention to prevent stroke. NICE has produced a patient decision aid to help people with atrial fibrillation make informed decisions about their treatment and care with their healthcare team.

Those people having vitamin K antagonists are at risk of under-coagulation, which may lead to thrombosis, and over-coagulation, which can result in haemorrhage. Both of these conditions can cause serious illness or death. People taking these drugs need regular monitoring of their international normalised ratio (INR). INR is a measure of the time it takes for blood to clot, and the prescribed dose of vitamin K antagonists can then be adjusted depending on the test result. CoaguChek XS is designed to measure INR and can support 2 different methods of care: self-testing and self-management. The person performing the test can either feed their result back to the relevant healthcare professionals, who may alter their dose of vitamin K antagonist (self-testing) or adjust the dosage themselves (self-management).

Measuring the person's time spent in therapeutic range (TTR) as a method of assessing INR control is an indicator of the standard of anticoagulation therapy. Results from the SPORTIF III and V trials showed that people with a TTR less than 60% have higher rates of annual mortality and major bleeding compared to patients with good INR control (TTR >75%).

It is estimated that there are currently 305,000 people^[1] in the UK on long-term anticoagulation warfarin therapy (the most common vitamin K antagonist used in the UK) for the management of atrial fibrillation.