Bradycardia-Associated Torsade de Pointes and the Long-QT Syndromes: A Case Report and Review of the Literature

Abstract

We report a case of bradycardia-associated torsade de pointes in which the underlying long-QT syndrome appeared to be attributable to primary cardiac conducting system disease. Our patient presented complaining of presyncope and syncope. Serial electrocardiograms obtained over a period of 10 years demonstrated slowly progressive conduction system abnormalities, and evaluation revealed no other cause. The patient's dysrhythmia was refractory to magnesium but abated with cardiac pacing at a moderate rate. A review of the relevant literature on congenital and acquired long-QT syndrome is included.

Sleep-Associated Torsades de Pointes: A Case Report

“…While previous studies have suggested a theoretical mechanism for TdP during sleep, we are not aware of any cases in the literature. 1 , 7 , 13 This patient ultimately did well with judicious treatment including prompt electrical therapy, magnesium, isoproterenol, and methadone cessation.…”

“…One uncommon cause of SCD is torsades de pointes (TdP), defined as polymorphic ventricular tachycardia occurring in a patient with an acquired or congenital long QT syndrome (LQTS). 1 TdP accounts for fewer than 5% of SCD cases, and death presumably occurs from its degeneration into ventricular fibrillation. 1 Medications with QT-prolonging effects are the most frequent cause of acquired LQTS, which is estimated to occur with approximately 2–3% of all prescriptions written.…”

“… 1 TdP accounts for fewer than 5% of SCD cases, and death presumably occurs from its degeneration into ventricular fibrillation. 1 Medications with QT-prolonging effects are the most frequent cause of acquired LQTS, which is estimated to occur with approximately 2–3% of all prescriptions written. 2 , 3 Another cause of acquired LQTS involves electrolyte disturbances, including hypokalemia, hypocalcemia, and hypomagnesemia.…”