1. Laboratory of Veterinary Surgery, Faculty of Agriculture, Miyazaki University, 1–1 Gakuen Kibanadai Nishi, Miyazaki 889–2192, Japan
2. Animal Cardiovascular and Thoracic Surgery Center, Sayamadai, Sayama-shi, Saitama 250–1304, Japan
3. Laboratory of Small Animal Internal Medicine II, School of Veterinary Medicine, Kitasato University, 23–35–1 Higashi, Towada, Aomori 034–8628, Japan