ELECTROCARDIOGRAPHIC CHANGES IN HYPOTHYROID PATIENTS WITH SPECIAL REFERENCE TO QT DISPERSION BEFORE AND AFTER TREATMENT WITH L-THYROXINE

Hypothyrodism is one of the commonly occurring endocrine abnormalities. It can cause various cardiovascular manifestations, one of which is malignant ventricular arrhythmias. So, if we study the markers of risk of these arrhythmias i.e QT dispersion in these hypothyroid patients and start with L-thyroxine therapy as early as possible, we can prevent these patients from developing ventricular arrhythmias and hence prevent sudden cardiac death in these patients. We conducted a study on newly detected 50 overt hypothyroid patients to find out the marker of arrhythmias i.e prolongation of QT dispersion in these patients and hence evaluate the effect of L-thyroxine on QT dispersion after 6 weeks. The hypothyroid patients were diagnosed by biochemical function test. Thereafter thorough clinical history, physical examination and necessary investigations were done. Then QT dispersion was calculated from the ECGs of these patients. These newly detected hypothyroid patients were then started on L-thyroxine therapy according to the TSH levels. These patients were again followed after 6 weeks of treatment and ECG was repeated to calculate QT dispersion. Hypothyroid patients showed increased QT cmax, QT cmin, QTc ,QT dispersion and corrected QT dispersion interval before treatment and all these variables decreased after treatment.