Stroke is the second-leading cause of death worldwide, according to the World Health Organization. In the U.S., about 800,000 strokes occur per year.
Of all strokes, 87% are ischemic. This means they occur when a clot blocks a blood vessel in the brain and stops blood flow. The remaining 13% are hemorrhagic, where a blood vessel ruptures and causes bleeding into brain tissue.
"In the U.S., stroke has dropped to the fifth-leading cause of death, due in part to improved systems of care, including earlier recognition and treatments, which have resulted in overall better outcomes," says Dr. Nycole Joseph, a vascular neurology fellow at Mayo Clinic's Comprehensive Stroke Center in Jacksonville, Florida.
