All of the statistics in the preceding Figures lead to the larger question: how to treat patients with AFib. To treat the AFib itself, of course, means consideration of questions such as rate control as opposed to rhythm control in some patients, but the main focus of this presentation will be on addressing the need for anticoagulation in patients with AFib. The real challenge in treating AFib, reaching across medical specialties, is prevention of stroke, which in current thinking means through application of prophylactic anticoagulation.

Historically oral warfarin has been the gold standard for anticoagulation therapy in patients with AFib. No doubt every clinician is aware of the several problems with warfarin:

• A delayed onset and offset of action,
• An unpredictable dose–response,
• A very narrow therapeutic index,
• Drug–drug and drug–food interactions.

There is also the issue of monitoring warfarin serum levels, which until now has been considered a limitation. There is a high risk of bleeding, particularly in patients who are also at high risk for stroke; in other words, exactly those patients who appear to be most in need of anticoagulation are oftentimes those who have the highest perceived bleeding risk.

As highlighted in Figure 7, the final limitation with warfarin is its relatively slow reversibility, although agents such as vitamin K and fresh frozen plasma (FFP) are available for more rapid reversal of warfarin’s anticoagulation effects.