Price tag doesn't always signify the success of a treatment. An expensive surgical procedure designed to prevent recurrent strokes does not appear to be any more effective than simply taking medication.

When it comes to helping heart failure patients avoid a stroke, common over-the-counter aspirin may be just as effective as a prescription blood thinner.

Prior to its approval last year, there was much debate about Xarelto ( rivaroxaban ), an anti-clotting drug designed to prevent stroke among patients with atrial fibrillation, a common heart arrhythmia.