Doctors frequently prescribe the generic warfarin or Coumadin® for atrial fibrillation (AF) because of the characteristics of this illness. Warfarin is important because it significantly reduces risk of stroke that is elevated due to the heart’s irregular rhythm, which can cause blood to aggregate and clot in the atria. Preventing blood clotting of this type is necessary and protective of the patient’s health. The medication may either be prescribed for a short duration, if other therapies can restore sinus rhythm, or patients may use it for long periods of time to address ongoing episodes of AF.
Sometimes doctors use Coumadin® for atrial fibrillation for short periods of time. Patients who will be undergoing synchronized cardioversion are on this drug to prevent stroke before and during treatment. The treatment itself may create higher risk for blood clotting, so an anti-clotting therapy is deemed necessary. Patients would probably take this medicine orally, usually once daily for at least four weeks before the planned procedure. The specific dose varies by individual.
Physicians also use Coumadin® for atrial fibrillation for those people who fail to have success with cardioversion or other treatments like ablation, or they prescribe it when patients are not candidates for these procedures and are treated with anti-arrhythmia medications. AF may still occur with treatment, or it may recur after treatments like cardioversion. Need for ongoing anti-clotting treatment is often established, and some patients will remain on warfarin, generally taking it once a day.
As stated, the dose of Coumadin® for atrial fibrillation is patient-specific and the medication needs to be monitored carefully. Most patients belong to a Coumadin® clinic that evaluates warfarin levels, or more often, blood clotting time (prothrombin time or PT), to make certain these fall within a therapeutic range. Abnormally high levels can lead to excessive bleeding and low levels may not successfully prevent blood clots. Patients in the therapeutic range still need to be careful, particularly when engaging in any activity that might cause head injury or severe bruising. Anything that might cause bleeding is a potential health hazard.
Additionally, warfarin interacts with a number of other drugs and common foods. A well-run warfarin clinic can make patients aware of foods and drugs they may need to avoid. Also, illness or infection can change levels, so most doctors recommend their patients with AF have a blood test at least once a month, and more often at onset of therapy of if PT is measured above or below the therapeutic range.
Patients may be confused because Coumadin® for atrial fibrillation is really prescribed for this condition because it doesn’t directly treat the arrythmias. Instead, it treats a side effect of AF: its tendency to increase the chance of having a stroke. Warfarin lowers this risk by 60% or more.