TG and thyroiditis: Indeed, diastolic dysfunction inhypothyroidism or subclinical hypothyroidism is reversible with thyroid hormone supplementation.27 A randomized clinical trial of patients with advanced HFrEF and low T3 levelsshowed improved neuroendocrine profile and ventricular performance after short-termintravenous T3.72 In an animal model of myocardial infarction-induced HF, T3 replacement toeuthyroid levels improved both systolic and diastolic functions.73 Even without primary thyroid disease or abnormal hormone plasma levels,thyroid hormone supplementation may have beneficial effects.