[1] Univ Penn, Dept Neurol, Philadelphia, PA 19104 USA
[2] Hartford Hosp, Stroke Ctr, Hartford, CT 06115 USA
[3] Cornell Univ, Weill Med Coll, Dept Med, Div Cardiol, New York, NY USA
[4] Cornell Univ, Weill Med Coll, Dept Publ Hlth, New York, NY USA
[5] Columbia Univ, Dept Med, Div Cardiol, New York, NY USA
[6] Toronto Western Hosp, Dept Neurol, Toronto, ON, Canada
[7] Univ Kansas, Med Ctr, Dept Neurol, Kansas City, KS 66103 USA