Original Article

The Development of the Yucatan Miniature Pig as a Chronic Model for Cardiac Surgery

The Cooper HospitaV University Medical Center, School of Cardiovascular Perfusion, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Camden, NJ

^* Address correspondence to: Roger A. Vertrees, BA, CCP, The Cooper Hospital/University Medical Center, School of Cardiovascular Perfusion, 310 Sarah Cooper Building, Camden, NJ 08103

Abstract

For purposes of developing a chronic model for coronary artery bypass grafting (CABG), the Yucatan miniature pig was selected. Its cardiac and vascular anatomical similarities to humans could be useful in achieving a model which would allow for investigations in vivo. Many difficulties have been encountered, resulting in one long-term survivor in the first series of nine animals. Of these nine pigs, there have been operative deaths due to friable venous tissue, fatal arrhythmia and exsanguination. Four others died in the post-operative period due to problems such as fatal arrhythmias, pneumothorax and hypoxia. Improved techniques in the anesthetic and surgical protocols, autologous recovery of the animals' lost blood, and the use of supplemental oxygen post-operatively have helped to overcome these problems. The next two animals survived well into the post-operative period. The last series of five Yucatan swine were all electively euthanized after they had recovered from their protocol. It is believed that the Yucatan swine, even though problems exist, may be an acceptable model for use in cardiac surgical procedures requiring a recovery or chronic phase.