A novel, form-stable, anatomically curved vascular prosthesis for replacement of the thoracic aorta.
OBJECTIVE
Current replacement of the thoracic aorta performed with straight vascular prostheses may cause kinking, potentially affecting hemodynamics and promoting vortices and thrombus formation. A novel vascular prosthesis, resistant to pressure-related shape deformation, was designed to imitate the curved anatomy of the thoracic aorta.


METHODS
A woven velour prosthesis was trimmed with cross-sutures along a marked line, resulting in a curved-shaped anatomic form, and was compared with conventional straight and thermally fixed curved grafts. The vascular prostheses were fixed at both ends at various base distances (8, 10, 12, 14, and 16 cm) and pressurized. To imitate the neck vessels an abutment was fixed at the upper convexity of the grafts. Radius of curvature or depth of kinking was measured at different pressures (100, 125, and 150 mm Hg). Pressure gradients and flow profiles were further analyzed in an aortic arch glass model.


RESULTS
When pressurized the straight and the thermally fixed protheses showed double kinking before and behind the abutment at all pressures and distances. Kinking depth increased with increasing pressure and less base distance. Transkinking pressure gradients increased with the degree of kinking. In a glass model flow profiles showed postkinking turbulences and vortex formation. The newly designed vascular prosthesis showed no kinking and remained form stable at all test conditions.


CONCLUSIONS
This novel curved vascular prosthesis for replacement of the thoracic aorta demonstrates form stability compared with conventional straight and thermally fixed vascular prostheses in an aortic arch model, with smaller pressure gradients and flow disturbances.
Misfeld
Martin
M
Clinic of Cardiac Surgery, University Clinic of Schleswig-Holstein, Campus Lübeck, Lübeck, Germany.
Scharfschwerdt
Michael
M
Sievers
Hans-H
HH
D001013:Aorta, Thoracic / Q000601:surgery*; D001807:Blood Vessel Prosthesis; D008955:Models, Cardiovascular