The CarboMedics "Top-Hat" supraannular prosthesis

Background. The CarboMedics "Top-Hat" supraannular prosthesis was designed to permit the implantation of a larger prosthesis. Methods. Between June 1993 and November 1996, 127 patients (average age, 61 .8 +/- 10.2 years) received a CarboMedics "Top-Hat" supraannular aortic pro sthesis. The average follow-up was 15.7 months, and all surviving patients underwent echocardiographic study. This group is compared with 656 patients in whom a standard CarboMedics prosthesis was implanted and also with 2,92 7 patients who received other aortic prostheses. Results. Using the standard and the supraannular sizers, there was an avera ge increase of one size in favor of the supraannular prosthesis: 18.9 +/- 2 .8 mm standard versus 20.8 +/- 2.6 mm supraannular (p < 0.005). For each pr osthesis size (19 to 23 mm), the body surface area of the patients in whom a CarboMedics supraannular prosthesis was implanted was significantly small er than that in those who received a CarboMedics standard prosthesis or any other model. Hospital mortality was 3.9%, and late mortality was 5.5%. The actuarial survival was 86.5% +/- 3.9% at 42 months. Conclusions. Using the CarboMedics supraannular prosthesis allows implantat ion of a larger prosthesis compared with the standard CarboMedics prosthesi s or other models. This advantage is especially important in patients with a small aortic root. (Ann Thorac Surg 1999;67:1299-303) (C) 1999 by The Soc iety of Thoracic Surgeons.