Correspondence to: Masaki Ieda, MD, PhD, Department of Cardiology, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba City, Ibaraki 305-8575, Japan. Email

E-mail Address: [email protected]

https://orcid.org/0000-0003-4724-3299

Departments of Cardiology, University of Tsukuba, Tsukuba City, Ibaraki, Japan. (T.S., Y.Y., M. Isomi, R.F., Y.A., T.A., K.N., M. Ieda)