Philip M. Tetzlaff

Developing an animal model for the study of fusion using RF energy

BACKGROUND: A reliable method of blood vessel fusion or sealing has been developed. This method works by applying RF energy and pressure to the walls of a vessel to create a seal. Several methods are used to evaluate the quality of the seal. The main criteria include pressurizing the vessel to failure and using histology to evaluate the integrity of the seal. Burst pressure testing quantifies seal quality, and histology stains reveal the fusion quality of the seal. In addition, histology can show the comparison of morphology and degree of fusion in different tissues. The purpose of the study was to develop an animal model for the human coronary artery bypass graft (CABG) and saphenous vein harvest procedure. METHODS: Experiments were conducted on ovine femoral veins and porcine epigastric veins to demonstrate, through histology and burst testing, the quality of seals. This research details the process of developing an animal model that best approximates the traditional harvest of the saphenous vein for the CABG procedure. RESULTS: Through a series of acute and chronic labs, this research developed a procedure on the ovine model to simulate a peripheral vascular procedure, similar to a femoral bypass. This peripheral vascular procedure on the ovine uses the femoral vein as an interpositional graft onto the femoral artery. In addition, this research identified a second animal model on which to evaluate the healing effects of sealed side branches in a cardiovascular procedure. This research path used the porcine model for a CABG procedure. The epigastric vein was harvested as an autologous vein graft for bypassing the LAD on the pig heart.