Transauricular Arterial or Venous Access for Cardiovascular Experimental Protocols in Animals Dimitris Karnabatidis, MD, PhD, Konstantinos Katsanos, MD, Athanasios Diamantopoulos, MD, George C. Kagadis, PhD, and Dimitris Siablis, MD, PhD PURPOSE: To describe a safe percutaneous method of transauricular endovascular access in small and large animals that uses basic catheter-based interventional skills and renders surgery and general anesthesia with intubation unnecessary. MATERIALS AND METHODS: Twenty New Zealand White rabbits and five domestic juvenile swine were used in the experiments. Animals were restrained in the supine position after induction of dissociative anesthesia. Transau- ricular endovascular access was accomplished by percutaneous catheterization of the auricular artery or vein, roadmap imaging, introduction of a 0.018-inch hydrophilic guide wire, and over-the-wire vascular sheath insertion after serial tract dilations. RESULTS: Technical success rates were 90% and 100% for intraarterial and endovenous access in the rabbit, respectively, and 100% for both routes in the pig. The largest sheaths inserted were 5 F in the rabbits’ aortae, 7 F in the rabbits’ venae cavae, 6 F in the pigs’ aortae, and 8 F in the pigs’ venae cavae. Animal recovery was uneventful, and 48-hour necropsy detected only minor perivascular hematoma in cases of transauricular intraarterial access. Peripheral, intracoronary, intrapulmonary, and intracerebral selective vascular access was safe and feasible. A method of reserving the transauricular endovascular access for future interventions or follow-up by placement of indwelling hydrophilic catheters was also established. CONCLUSIONS: Transauricular endovascular access is a successful technique for establishing and maintaining intraarterial or endovenous vascular access. It obviates surgical cutdown and sacrifice of the femoral and cervical vessels and might considerably improve and expedite cardiovascular experimental protocols in small and large animals. J Vasc Interv Radiol 2006; 17:1803–1811 THE field of experimental cardiovas- cular intervention comprises various studies of vascular restenosis (1– 4), therapeutic angiogenesis (5–7), embo- lization treatment (8,9), aneurysm therapy (8,10,11), and research and de- velopment of new interventional tech- niques and instruments (12,13). Tradi- tionally, intraarterial and endovenous access in an animal is achieved by sur- gical cutdown of the femoral or cervi- cal arteries and veins, which may be finally ligated and thrombosed, limit- ing reuse of the vessel (5,10,14,15). These methods are time-consuming, require experienced surgical person- nel, and are associated with postsurgi- cal pain and complications such as bleeding, local infections, or systemic sepsis that may turn out to be fatal. A nonsurgical percutaneous tech- nique of endovascular access that could enable rapid, safe, and repeat- able cannulation of the central arterial and/or venous system may serve as an excellent experimental platform for catheter-based diagnostic and thera- peutic cardiovascular interventions. The present report demonstrates a minimally invasive method of central vascular access in small and large an- imals (New Zealand White rabbits and domestic pigs) that uses the auricular artery and vein and obviates surgical sacrifice of the femoral and cervical vessels. A complete series of routine endovascular procedures could be performed through the proposed trans- auricular endovascular access. Finally, an additional method for reservation of the transauricular access for further or repeated interventions, as well as From the Departments of Radiology (D.K., K.K., A.D., D.S.) and Medical Physics (G.C.K.), School of Medicine, University of Patras, GR 26500, Rion, Greece. Received March 28, 2006; revision requested July 10; final revision received August 16; and ac- cepted August 27. Address correspondence to D.K.; E-mail: karnaby@med.upatras.gr None of the authors have identified a conflict of interest. © SIR, 2006 DOI: 10.1097/01.RVI.0000244836.16098.B1 1803