Hyponatremia after initiation of angiotensin‐converting enzyme inhibitor in a geriatric patient with chronic heart failure: A case of mineralocorticoid‐responsive hyponatremia of the elderly. Issue 5 (May 2017) - Iwagaki, Harei; Haruki, Nobuhiko; Junichi, Nakamata; Tamura, Masahito; Otsuji, Yutaka