Mr. D., a 75-year-old retired university professor with a prior stroke, wakes up in the morning, drives to the hospital to have blood drawn to adjust his warfarin dosage and then goes to work. A couple of hours later, he gets a call from the nursing team telling him how to adjust the dose: “starting today you should take 7.5 mg of warfarin on Mondays, Wednesdays and Fridays. On the other days of the week you can keep up with the 5 mg pill you are used to. If you do not have a 7.5 mg pill you can cut the 5 mg in half and take one and a half pills on those days. It is not too complicated, is it? By the way, remember to go slow on that kale and spinach I know you like!”. Were it not for the fact the Mr. D. also takes enalapril and atenolol for his blood pressure and to control the heart rate of his atrial fibrillation (AF), a statin for secondary prevention since the stroke, and metformin for his diabetes; cutting pills in half and remembering on what day he should take which dosage should be too complicated.

Unfortunately, Mr. D. is about the average non-valvular AF patient seen in clinics in private practices in Brazil and places around the world, though patients from the Brazilian Unified Health System (Sistema Unico de Saúde, SUS) usually spend substantially more time at the hospital waiting for the results in person or coming back the next day to check them, due to more limited resources to contact patients over the phone.

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