[1] Univ British Columbia, Dept Radiol, Div Cardiol, Vancouver, BC, Canada
[2] Univ British Columbia, Dept Med, Div Cardiol, Vancouver, BC, Canada
[3] New York Presbyterian Hosp, Weill Cornell Med Coll, Div Cardiol, Dept Med, New York, NY USA
[4] New York Presbyterian Hosp, Weill Cornell Med Coll, Dept Radiol, New York, NY USA