1. Division of Internal Medicine, Onagawa Municipal Hospital
2. Department of Cardiovascular Medicine, Tohoku University Graduate School of Medicine
3. Department of Cardiology, Mie University Graduate School of Medicine
4. Department of Cardiology, Iwate Prefectural Central Hospital
5. Division of Internal Medicine, Sendai Tokushukai Hospital
6. Shinshu University School of Health Sciences
7. Division of Internal Medicine, Saito Hospital