In vivo testing of an intra-annular aortic valve annuloplasty ring in a chronic calf model

Eur J Cardiothorac Surg. 2012 Jul;42(1):149-54. doi: 10.1093/ejcts/ezr273. Epub 2012 Feb 22.


Objective: To increase applicability and stability of aortic valve repair, a three-dimensional aortic annuloplasty ring has been developed for intra-annular placement. The goal of this study was to test the safety of this device with in vivo implantation in the calf model.

Methods: In 10 chronic calves, the HAART annuloplasty ring was sutured to the aortic valve annulus using cardiopulmonary bypass. The animals were recovered and followed for 1-2 months. Serial echocardiography was used to evaluate valve competence, and contrast aortograms and CT angiograms were obtained in selected animals. After completion of follow-up, each animal was euthanized, and aortic endoscopy was performed under water distension in five. Full autopsies with histologic examinations were performed.

Results: All animals survived surgery. Two were euthanized in the first week for complications, and the remaining eight calves were followed uneventfully for the 1-2 months. Serial echocardiography showed completely competent valves in all but one animal, in which the ring was intentionally up-sized to test the sizing strategy. Contrast aortographic and CT angiographic findings were similar to the echocardiograms. Postmortem examination showed proper seating of all rings with endothelialization at 1-2 months. All valves demonstrated good leaflet coaptation and no abnormalities.

Conclusions: In vivo testing of a three-dimensional aortic annuloplasty ring in a chronic calf model proved to be very successful and safe. Using the sizing and implant strategies developed, human trials seem indicated.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aortic Valve / diagnostic imaging
  • Aortic Valve / surgery*
  • Cardiac Valve Annuloplasty / instrumentation*
  • Cattle
  • Equipment Safety
  • Follow-Up Studies
  • Heart Valve Prosthesis Implantation / instrumentation*
  • Heart Valve Prosthesis*
  • Models, Animal
  • Radiography
  • Ultrasonography