Incidence of and risk factors for pulmonary autograft dilation after ross aortic valve replacement

Background. The Ross procedure is an alternative to mechanical aortic valve replacement in the young. Early dilation of the pulmonary autograft root exposed to the systemic circulation has been reported. The aim of our study is to define the prevalence, risk factors, and consequences of autograft dilation. All consecutive adult and pediatric patients who underwent Ross procedure at our institution were retrospectively reviewed for autograft dilation. Methods. Between 1993 and 2005, 170 patients (mean age, 24.9 +/- 15.5 years; range, 1 month to 61 years) underwent Ross aortic valve replacement: 48% were younger than 19 years old. Eighty-seven additional procedures were performed in 58 patients (34%) at the time of the Ross procedure. End points of the study were freedom from autograft dilation (z value more than +2.0), autograft dysfunction, autograft reoperation, and autograft replacement. Results. There were 2 early and 1 late deaths during a mean follow-up of 5.1 +/- 3.0 years (range, 1 month to 12 years). Actuarial survival at 10 years was 98%. Autograft dilation was identified in 31 patients (19%). Regurgitation (>2+) was identified in 12 patients (7%); all 12 had autograft dilation. At 10 years, freedom from autograft dilation was 82%, freedom from autograft dysfunction was 92%, freedom from reoperation on autograft was 92%, and freedom from autograft replacement was 96%. Cox proportional hazard analysis identified preoperative aortic annulus dilation (z value more than +2.0; p = 0.004), younger age (p = 0.05), time of surgery (before 2001; p = 0.002), and male sex (p = 0.01) as predictive of autograft dilation, whereas preoperative ascending aorta diameter (p = 0.01), male sex (p = 0.03), and postoperative systemic hypertension (p = 0.05) were predictive of autograft dysfunction. Conclusions. Significant autograft dilation is not common after the Ross procedure. Significant autograft dysfunction affects a minority of patients, but it is more prevalent in those with autograft dilation.