A-Fib (Atrial Fibrillation) is the most common type of cardiac arrythmia. 1 in 4 Americans over 40 have a risk of developing A-Fib. You can recognize it from the moment when you go to take a radial pulse and it's nowhere near a predictable rhythm. 8% of adults over age 80 have A-Fib. Some people have spontaneous A-Fib spells, some suffer from A-Fib during exertion, and some have continuous (chronic) A-Fib. Approximately 30% of A-Fib patients don't know that they have A-Fib.
Simply, there's extra electrical impulses going on in your heart, and the atria are beating faster than the ventricles, creating arrythmia. It's not life-threatening on it's own, but it can cause palpitations, fainting, chest pain, CHF, and most importantly, strokes.
Patients with A-Fib are 7 times more likely to have strokes than the regular population. Blood can pool and clot due to inadequate contractions of the atria. A-Fib strokes are therefore typically ischemic.
35% of patients with A-Fib will suffer strokes if untreated.
15% of all stroke patients have A-Fib
25% of A-Fib stroke patients have no prior diagnosis of A-Fib
23% of A-Fib stroke patients die (compared to 8% of non-A-Fib stroke patients)
44% of A-Fib stroke patients suffer serious neurological damage
Now that I've overwhelmed you with numbers, enter Coumadin. Coumadin, or Warfarin, as we all know, is an anti-coagulant (blood-thinner). Anti-coagulants prevent clots. Therefore, your patient with a PMH of "A-Fib (On Coumadin)" most likely has chronic A-Fib and other risk factors for stroke.
Some A-Fib patients may use Aspirin, Heparin, or Dabigartan for the same effect. Aspirin is more common in younger A-Fib patients.
They may also be on medications to control their heart rate such as: Metoprolol, Atenolol, Bisoprolol, Diltiazem, Verapamil, or Digoxin. (I see the first and last regularly with my geriatric patients, even if they don't have a PMH of A-Fib. More on those some other post.)
Atrial Fibrillation - Wikipedia
Atrial Fibrillation - a-fib.com