1. University of Calgary, Calgary, Alberta, Canada (R.S., P.F., C.A.M., D.R., S.S., C.M.)
2. University of Western Ontario, London, Ontario, Canada (A.T.)
3. University of Sherbrooke, Sherbrooke, Quebec, Canada (F.A.)
4. McMaster University, Hamilton, Ontario, Canada (J.G.)
5. Instituto Nacional de Cardiología Ignacio Chávez, Mexico City, Mexico (M.M.)
6. University of British Columbia, Vancouver, British Columbia, Canada (A.D.K.)
7. University of Montreal, Montreal, Quebec, Canada (T.K.)
8. University of Calgary, Calgary, Alberta, Canada, and Vanderbilt University School of Medicine, Nashville, Tennessee (S.R.R.).