1 Department of Cardiovascular Surgery, Hôpitaux Universitaires de Strasbourg, NHC - Hôpital Civil, 1, place de L'Hôpital, BP 426, Strasbourg, 67091 Cedex, France. Electronic address: michel.kindo@chru-strasbourg.fr.
2 Department of Cardiovascular Surgery, Hôpitaux Universitaires de Strasbourg, NHC - Hôpital Civil, 1, place de L'Hôpital, BP 426, Strasbourg, 67091 Cedex, France.