[1] Dalhousie Univ, New Brunswick Heart Ctr, St John, NB, Canada
[2] Univ Manitoba, Dept Surg, Max Rady Coll Med, Winnipeg, MB, Canada
[3] Univ Calgary, Libin Cardiovasc Inst, Calgary, AB, Canada
[4] Univ Montreal, Montreal Heart Inst, Dept Surg, Montreal, PQ, Canada
[5] Univ British Columbia, St Pauls Hosp, Dept Surg, Vancouver, BC, Canada
[6] Univ British Columbia, Royal Columbian Hosp, Dept Surg, Vancouver, BC, Canada
[7] Laval Univ, Quebec Heart & Lung Inst, Quebec City, PQ, Canada
[8] Univ Alberta, Mazankowski Heart Inst, Edmonton, AB, Canada
[9] Univ Toronto, Dept Surg, Div Cardiovasc Surg, Toronto, ON, Canada
[10] Univ Ottawa, Ottawa Heart Inst, Div Cardiac Surg, Ottawa, ON, Canada
[11] Dalhousie Univ, Maritime Heart Ctr, Halifax, NS, Canada
[12] McMaster Univ, Hamilton, ON, Canada
[13] McGill Univ, Jewish Gen Hosp, Dept Surg, Montreal, PQ, Canada