La procédure de Ross : propriétés biomécaniques de l'artère pulmonaire en fonction du phénotype valvulaire aortique
The Ross procedure: biomechanical properties of the pulmonary artery according to aortic valve phenotype  Pierre Olivier Dionne, Evan Wener, Alexander Emmott, Raymond Cartier, Rosaire Mongrain, Richard Leask and Ismail El-Hamamsy OBJECTIVES: The aim of this study is to determine whether patients undergoing the Ross procedure with bicuspid aortic valves have different pulmonary artery biomechanical properties from those with tricuspid valves.  METHODS: Thirty-two pulmonary arteries and 20 aortas were obtained from patients undergoing the Ross procedure at the time of surgery, from a cohort of 32 patients. Histological analysis and ex vivo equi-biaxial tensile testing completed within 8 hours of surgery were used to evaluate differences in patient groups and between the pulmonary artery and the ascending aorta.  RESULTS: There was no difference in thickness among pulmonary arteries when compared according to aortic valve phenotype (P = 0.94). There was no difference in the tensile tissue properties among aortas and pulmonary arteries when compared according to aortic valve phenotype, in either the circumferential or longitudinal axis. When compared according to the main surgical indication, pulmonary artery walls from patients with pure aortic regurgitation were less stiff than their counterparts (P = 0.002). There was no difference in the number of elastic lamellae in pulmonary artery specimens from the three different aortic valve phenotypes (Tricuspid, bicuspid or unicuspid), as well as in the aortic specimens.  CONCLUSION: No significant differences were observed in the biomechanical properties of pulmonary arteries when compared according to aortic valve phenotype.
Dilatation Ross procedure Pulmonary artery Biomechanics