Torsade de Pointes and Marked QT Prolongation in Association with Hypothyroidism

Excerpt

Sustained ventricular tachyarrhythmias occur infrequently in patients with hypothyroidism (1, 2). In all previous reports (3-8), the morphologic features of ventricular tachyarrhythmias were not well characterized, and precipitating factors might have resulted in the tachyarrhythmias without hypothyroidism. The occurrence of torsade de pointes caused by hypothyroidism has not been well documented. We report the case of a patient with severe hypothyroidism in whom torsade de pointes occurred in association with marked prolongation of the QT interval. In evaluating the QT interval, we also retrospectively reviewed the medical records of 14 consecutive patients with hypothyroidism to determine the frequency and magnitude