1. Department of Internal Medicine, Tokyo Bay Urayasu Ichikawa Medical Center, Urayasu, Chiba, Japan
2. Department of Cardiology, Tokyo Bay Urayasu Ichikawa Medical Center, Urayasu, Chiba, Japan
3. Department of Critical Care Medicine and Pulmonary Medicine, Tokyo Bay Urayasu Ichikawa Medical Center, Urayasu, Chiba, Japan