1. Department of Cardiology and HematologyFukushima Medical UniversityFukushimaJapan
2. Department of CardiologyOhara Medical CenterFukushimaJapan
3. Second Department of MedicineShirakawa Kosei General HospitalShirakawaJapan
4. Department of CardiologyFukushima Red Cross HospitalFukushimaJapan
5. First Department of Internal MedicineYamagata University School of MedicineYamagataJapan