Hemodynamics of the Freestyle bioprosthesis in young patients.

The objective of this study was to analyze hemodynamics of the Freestyle stentless bioprosthesis in young patients compared with the older age group. The Freestyle aortic bioprosthesis is a stentless aortic xenograft. Hemodynamics are proven to be good in older patients for a long period. Experience is limited in the younger age group. Therefore the hemodynamics of 71 patients younger than 60 years (14-59 years) were compared with the data of 471 patients older than 60 years (60-86 years) during a follow-up period of 6 years. In the study, 542 consecutive patients with a Freestyle aortic bioprosthesis underwent an echocardiographic and Doppler examination according to a common protocol. Investigations were done within 4 weeks after operation, after 3 to 6 months, and then every year. Mean gradients of the young patients were 8.7 +/- 5.3 mm Hg at discharge and remained between 5.2 +/- 3.9 mm Hg and 11 +/- 5.6 mm Hg during the complete follow-up period. Gradients of the older patients were 8.3 +/- 5.4 mm Hg at discharge and remained between 5.1 +/- 3.7 mm Hg and 6.5 +/- 7.9 mm Hg. Cardiac index during the follow-up period was equal in both groups. Doppler values were evaluated for the Freestyle stentless porcine bioprostheses in the aortic root both for patients younger than 60 years and patients over 60 years of age. Midterm hemodynamic performance is equal in both groups.