Acquired Torsades de Pointes

Torsades de pointes may be inherited or acquired. Patients with specific genetic mutations may have the inherited long QT syndrome, in which the QT interval is prolonged, and these patients are at risk for torsades de pointes. Acquired torsades de pointes maybe caused by numerous drugs (Table 6-13) the list of drugs that are known to cause torsades de pointes continues to expand. 

Verduyn AC, Vos MA, van der Zande J et at. (1997) Further observations to elucidate the role of interventricular dispersion of repolarization and early afterdepolarizations in the genesis of acquired Torsade de Points arrhythmias. J Am Coll Cardiol 30 1575-1584... 

The impairment of critical cellular functions can result in systemic toxicities such as those associated with the neuromuscular system (tremor, cardiac arrhythmia, and paralysis). renal (microtubule function), and vasculature (leaky blood vessels). A noteworthy example is the acquired long QT syndrome (LQTS) associated with blockade of cardiac ion channels (14-16). LQTS results in cardiac arrhythmias, torsade de pointes, ventricular fibrillation, and can lead to sudden death. One such ion channel is the HERG protein, respon-... 

KvLQTl (KCNQl), HERG (KCNH2), SCN5A Acquired long-QT syndrome (patients with drug-associated torsades de pointes) Mutations in these genes 5/92 patients has mutations 55... 

Khan lA Clinical and therapeutic aspects of congenital and acquired long QT syndrome. Am J Med 2002 112(1) 58-66. [PMID 11812408] (Review of causes of prolonged QT interval and management of torsade de pointes.)... 

Thomas SH, Behr ER (2016) Pharmacological treatment of acquired QT prolongation and torsades de pointes. Br J Clin Pharmacol 81 420-427... 

Totterman KJ, Tuito H, PelUnen T (1982) Overdrive pacing as treatment of sotalol-induced ventricular tachyarrhythmias (torsade de pointes). Acta Med Scand Suppl 668 28-33 Tsutsui K, Hayami N, Kunishima T et al (2012) Dexmedetomidine and clonidine inhibit ventricular tachyarrhythmias in a rabbit model of acquired long QT syndrome. Circ J 76 2343-2347 Turner JR (2010) New drug development an introduction to clinical trials, 2nd edn. Springer, New York... 

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