[1] Dokkyo Med Univ, Sch Med, Dept Cardiac & Vasc Surg, Mibu, Japan
[2] Dokkyo Med Univ, Nikko Med Ctr, Dept Cardiol, Nikko, Japan
[3] Dokkyo Med Univ, Sch Med, Dept Pharmacol Toxicol, Mibu, Japan
[4] Chiba Univ, Dept Hlth Promot Nursing & Midwifery, Grad Sch Nursing, Chiba, Japan
[5] Kanagawa Univ Human Serv, Dept Liberal Arts & Human Dev, Yokosuka, Japan
[6] Maebashi Red Cross Hosp, Dept Cardiovasc Surg, Maebashi, Japan
[7] Dokkyo Med Univ, Dept Cardiovasc Med, Sch Med, Mibu, Japan
[8] 880 Kitakobayashi, Mibu, Tochigi 3210293, Japan