Corrigendum: Malnutrition and Frailty Are Critical Determinants of 6-Month Outcome in Hospitalized Elderly Patients With Heart Failure Harboring Surgically Untreated Functional Mitral Regurgitation - Miura, Masakazu; Okuda, Shinichi; Murata, Kazuhiro; Nagai, Hitoshi; Ueyama, Takeshi; Nakao, Fumiaki; Shimokawa, Mototsugu; Yamamoto, Takeshi; Ikeda, Yasuhiro (Frontiers in Cardiovascular Medicine, 2022)