In many cases of cryptogenic stroke, or stroke of undetermined cause -- which accounts for about 25 percent of all strokes -- physicians believe undiagnosed atrial fibrillation (abnormal heart beat) may be to blame.

Heart disease costs are predicted to triple in the next 20 years in the U.S., according to predictions from the American Heart Association (AHA).

Costs associated with treating heart disease and heart conditions increased more than 200 percent in Canada from 1996 to 2006, and are expected to triple in the U.S. by 2030.