Wherever and whenever you are, if you are using the blood thinning tablet Coumadin (Warfarin), you can measure the INR yourself with this device. INR is an important value and lifetime INR measurement is necessary after heart valve surgeries because arrhythmia patients have to use Coumadin (Warfarin). This measurement, which is usually done in the hospital, can also be done with a drop of blood thanks to this device. Adjusting the INR value well can reduce drug-related complications, as well as reduce the risks of clotting or bleeding, especially after valve surgeries.