TG and heart failure: The direct toxic effect of thyroid hormone and indirect action via catecholamine on the cardiovascular system can lead to a typical hyper-dynamic circulatory state which manifested as accelerated HR, increased blood volume, increased stroke volume (SV), increased LVEF, and high cardiac output.[15] With long-lasting excessive thyroid hormone, functional and morphological abnormalities occur in the heart, and compensatory cardiac hypertrophy exists which ultimately leads to heart failure.[16] Congestive heart failure is the well-recognized complication of HT.