Background: Historically, the surgical implantation of a mechanical valve in the descending aorta permitted the reduction of regurgitant flow in chronic aortic insufficiency. Long term clinical results were excellent but with the development of the pump oxygenators, orthotopic valvar replacement has become the conventional treatment of aortic valve diseases. We wanted to reconsider the ectopic position in sheep using a new percutaneous technique.
Material/methods: A biological valve harvested from a bovine jugular vein was sutured into a vascular stent. After the creation of a severe aortic insufficiency, the valved stent was percutaneously implanted according to standard stent placement techniques. Hemodynamic and angiographic evaluations were carried out during the procedure; finally, anatomic evaluation was performed.
Results: A severe aortic insufficiency was created in all animals (9/9). 3 had a single stent in the descending aorta and 3 had an additional stent in the brachiocephalic trunk. A control group of 3 animals had no valve implantation. One sheep had an additional valve implant because one overdilated stent had become insufficient. Early evaluation of the implanted valve function confirmed the perfect competence of 9 out of 10 valved stents. However, for unknown reasons all the animals died within 24 hours after the procedure.
Conclusions: Percutaneously implanted valves in the thoracic aorta of sheep with massive aortic insufficiency function well in the acute study. In comparison to previous surgical results, this technique might become an alternative to surgery in patients with chronic aortic insufficiency in whom perioperative risks are high.