Dilated cardiomyopathy with long QT secondary to hypothyroidism and hypocalcaemia in patient with post total thyroidectomy: A case report

The linkage between cardiac dysfunction and the lack of thyroid hormones has been well elucidated. A case involving a woman aged 44 years suffering a dilated cardiomyopathy (DCM) and long QT secondary to hypothyroidism and hypocalcaemia emerges. Thyroid hormone acts on the myocardium of the heart and peripheral blood vessels. There are two types of thyroid hormone effects, such as genomic and non-genomic. These effects are associated with cardiovascular and hemodynamic function. The prolongation of the QT interval is the most overlooked and well-documented sign in hypothyroidism. Ventricular fibrillation is usually the leading factor for the long QT syndrome. The incidence is characterized by an increased risk of sudden death and the abnormal QT-interval prolongation on the surface of ECG. The mechanism of hypothyroidism on the occurrence of the ventricular tachycardia and the OT prolongation is unrecognized, and although coexistent, the effects might be distinctive.