Case Studies In Small Animal
Tiffany's owners were given a reasonably poor prognosis. They were told that the combination of a stenotic lesion producing a pressure overload and a regurgitant lesion (i.e., tricuspid valve dysplasia) usually results in heart failure. Since the right atrium was already severely enlarged, they were told that this probably would happen in the near future. They decided they wanted to do everything they possibly could for Tiffany and told us that cost was not a concern. The human literature indicated that balloon valvuloplasty was not a good option for this lesion and after looking at the lesion on TEE we concurred. Consequently, we called Dr. Chris Orton at Colorado State University and talked to him about possible surgical options. We were surprised to learn that he had performed surgery on three other dogs with lesions similar to Tiffany's and that surgery had gone well in these three dogs. The surgical procedure consisted of placing the dogs on cardiopulmonary bypass, making an incision in the region of the obstruction, removing a portion of the obstruction, and placing a Gortex patch over the region to allow it to expand. Subsequent to this we put Tiffany's owners in contact with Dr. Orton and a surgery date was set. We told the owners to watch for signs of right heart failure and sent them home. We were contacted via email by Dr. Orton about 10 weeks later. This was his report.
Just quick note to let you know about the outcome of Tiffany's surgery. Tiffany presented to us for surgery on Monday. At presentation she had severe ascites and right sided CHF. I had spoken to the owners about 10 days earlier and they indicated at that time that her abdomen had become swollen. I told them to contact you about possible medication, but they elected not to do this. Anyway, we took her to surgery yesterday to correct her right mid-ventricular obstruction. Unfortunately she experienced ventricular fibrillation just as we were opening the thorax. We performed internal cardiac massage while we worked to get her on cardiopulmonary bypass. This took about 15 minutes. All indications from our monitoring was that cardiac massage was delivering at least a minimal cardiac output. After establishing CPB, her heart and organ function seemed to quickly recover so we treated her brain for possible ischemic injury and proceeded with surgery. The rest of the surgery went well and all indications were that we had an excellent cardiac repair. She came off CPB easily and was hemodynamically stable after surgery. Unfortunately, it became apparent in the hours after surgery that she was unresponsive. Her pupils were fixed and she did not have a corneal reflex. This morning a BAR showed no response. Based on these findings we believe that she experienced brain death. She was taken of her ventilator this morning with her owners present.
©Mark D. Kittleson, D.V.M., Ph.D. All rights reserved.