About 15 years ago, I developed CHF from my atrial fibrillation. At first they put me on Coumadin, which does have to be tested all of the time, and the amount adjusted. Then, I signed up for a research clinic and was put on apixaban. That was much easier, and you do not have to worry about eating foods that thin or thicken the blood. It works by making the blood too slippery to clot rather than thinning it.
After my heart procedure last summer, they changed me over to Xaralto, which is about the same kind of medicine, and only one little pill every night.
You do have to be careful about bleeding; but that is safer than taking a chance on having a stroke. Now that the cardioversion has stopped the a-fib; my cardiologist said they will take me off of the Xaralto once I have been better for a year.
Coumadin (warfarin) comes from a mold found on grain. It was discovered when cows were fed grain from a silo that had moldy silage in it, and the cows bled to death internally, and died.
Once they discovered what was killing the cattle; they realized that it could also cause a rodent to bleed to death, so they made it into rat poison.
Somewhere along the line, someone decided that if it were regulated, that it could be used to thin blood in people who were at risk of clotting.
I definitely think that using fish oil, and other foods that naturally keep the blood thin is an excellent idea.