1. Division of Cardiology, Department of Internal Medicine; The Jikei University School of Medicine; 3-25-8 Nishi-shimbashi, Minato-ku Tokyo 105-8461 Japan
2. Department of Cardiology; Keio University School of Medicine; Tokyo Japan
3. Heart and Vascular Institute; University of Pittsburgh Medical Center; Pittsburgh PA USA
4. Section of Cardiology, Sarver Heart Center; Banner University Medical Center; Tucson AZ USA