[1] Univ Manitoba, Sect Cardiac Surg, St Boniface Gen Hosp, Winnipeg, MB R3T 2N2, Canada
[2] Lankenau Inst Med Res, Main Line Hlth, Dept Cardiac Surg Res, Wynnewood, PA 19096 USA
[3] Lankenau Med Ctr, Main Line Hlth, Dept Cardiac Surg, Wynnewood, PA 19096 USA
[4] Univ Hosp Cleveland Med Ctr, Cardiac Surg Dept, Cleveland, OH 44106 USA
[5] Univ Florence, Clin & Expt Dept, Cardiac Surg Unit, I-50121 Florence, Italy
[6] Univ Calgary, Libin Cardiovasc Inst, Div Cardiac Sci, Sect Cardiac Surg, Calgary, AB T2N 1N4, Canada
[7] Maastricht Univ Hosp, Cardiothorac Dept, NL-6229 HX Maastricht, Netherlands
[8] Univ Siena, Dept Med Biotechnol, Div Cardiol, I-53100 Siena, Italy