Effect of a Telemedicine Model on Patients With Heart Failure With Reduced Ejection Fraction in a Resource-Limited Setting in Vietnam: Cohort Study. - Nguyen, Hoai Thi Thu; Tran, Hieu Ba; Tran, Phuong Minh; Pham, Hung Manh; Dao, Co Xuan; Le, Thanh Ngoc; Do, Loi Doan; Nguyen, Ha Quoc; Vu, Thom Thi; Kirkpatrick, James; Reid, Christopher; Nguyen, Dung Viet (Journal of Medical Internet Research, 2025)