[1] Toranomon Gen Hosp, Sleep Ctr, Tokyo, Japan
[2] Juntendo Univ, Nerima Hosp, Dept Cardiol, Tokyo, Japan
[3] Toranomon Gen Hosp, Dept Clin Physiol, Tokyo, Japan
[4] Perseus Prote Inc, Tokyo, Japan
[5] Toranomon Gen Hosp, Ctr Cardiovasc, Tokyo, Japan
[6] Jichi Univ, Saitama Med Ctr, Div Cardiovasc, Saitama, Japan