J. Vet. Sci. 2017; 18(1): 67-71  
Surgical access via right thoracotomy facilitates tricuspid valve surgery in sheep
Wolfgang Bothe1,2, Mahmoud Diab1, Romanus Ostermann1, Michael Schwarzer1, Luisa Woelfel1, Sabine Bischoff3, Harald Schubert3, Torsten Doenst1,*
1Department of Cardiothoracic Surgery, Jena University Hospital, Friedrich Schiller University, Jena 07747, Germany
2Department of Cardiovascular Surgery, Heart Center, University of Freiburg, Freiburg 79110, Germany
3Institute of Laboratory Animals Science and Welfare, Jena University Hospital, Friedrich Schiller University, Jena 07747, Germany
Correspondence to: Torsten Doenst
Tel: +49-3641-932-2901; Fax: +49-3641-932-2902; E-mail: doenst@med.uni-jena.de
Received: December 30, 2015; Revised: April 27, 2016; Accepted: June 8, 2016; Published online: March 30, 2017.
In quadrupeds, the three-dimensional orientation of the heart with respect to the thorax is fundamentally different from that in humans. In this study, we assessed the best surgical approach to the tricuspid valve in sheep. Firstly, different surgical access sites to the tricuspid valve were tested in sheep cadavers, the anatomy was analyzed, and the optimal surgical approach to the tricuspid valve was determined. Secondly - along with cardiopulmonary bypass and cardioplegic arrest -the chosen approach was tested in six adult sheep in vivo. Anatomical analyses revealed that a left thoracotomy provided optimal access to the aorta and left heart. However, visualization of the right heart was significantly impaired. In contrast, a right thoracotomy provided good access to the right heart, but the ascending aorta was difficult to approach. Therefore, in the in vivo studies, arterial cannulation was performed through a carotid (n = 4) or femoral (n = 2) artery. In conclusion, a right-sided thoracotomy allows good visualization of all components of the tricuspid valve complex in sheep, but not of the ascending aorta. Consequently, peripheral vessels are preferred for arterial cannulation. This work may stimulate the investigation of pathomechanisms and/or novel treatment options for tricuspid valve pathologies.
Keywords: animal model, cardiac surgery, tricuspid valve

© 2017 The Korean Society of Veterinary Science.