1 Institute for Clinical Evaluative Sciences, University of Toronto, Toronto, Canada; Peter Munk Cardiac Centre, University of Toronto, Toronto, Canada.
2 Institute for Clinical Evaluative Sciences, University of Toronto, Toronto, Canada; Peter Munk Cardiac Centre, University of Toronto, Toronto, Canada; Institute for Health Policy, Management and Evaluation, University of Toronto, Toronto, Canada; Joint Department of Medical Imaging, University of Toronto, Toronto, Canada. Electronic address: dlee@ices.on.ca.