1. Department of Cardiovascular Medicine, Kobe City Medical Center General Hospital , 2-1-1 Minatojima-minamimachi, Chuo-ku , Kobe, Japan
2. Department of Diagnostic Pathology, Kobe City Medical Center General Hospital , 2-1-1 Minatojima-minamimachi, Chuo-ku, Kobe 6500047 , Japan
3. Department of Cardiothoracic Surgery, Kansai Medical University , 2-5-1 Shinmachi, Hirakata 5731191 , Japan