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Long QT syndrome

Last updated: March 19, 2021

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Long QT syndrome (LQTS) is a congenital or acquired heart condition in which the QT interval (i.e., ventricular depolarization and repolarization) is prolonged. Most patients with LQTS are asymptomatic, but some present with seizures, syncope, or even life-threatening arrhythmias and sudden death. Treatment depends on the underlying cause: Beta blockers and implantable cardioverter defibrillator (ICD) insertion are commonly used for congenital LQTS, whereas treatment of the underlying cause (drug, electrolyte abnormality, etc.) is the first-line therapy for acquired LQTS.

A prolonged QT interval may be congenital or acquired.

Congenital LQTS

Acquired LQTS [7][8][9][10]

Compared to other class III antiarrhythmics, amiodarone uncommonly causes torsades de pointes.

All treatment modalities aim to reduce the risk and severity of cardiac events.

We list the most important complications. The selection is not exhaustive.

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  3. Jervell and Lange-Nielsen Syndrome.
  4. Jervell and Lange-Nielsen syndrome. http://www.orpha.net/consor/cgi-bin/Disease_Search.php?lng=EN&data_id=12056&Disease_Disease_Search_diseaseGroup=jervell&Disease_Disease_Search_diseaseType=Pat&Krankheite(n)/Krankheitsgruppe=Jervell-Lange-Nielsen-Syndrom&title=Jervell-Lange-Nielsen-Syndrom&search=Disease_Search_Simple. Updated: October 1, 2009. Accessed: December 6, 2017.
  5. Jervell and Lange-Nielsen Syndrome. https://ghr.nlm.nih.gov/condition/jervell-and-lange-nielsen-syndrome. Updated: November 7, 2017. Accessed: November 13, 2017.
  6. Romano-Ward Syndrome. http://www.orpha.net/consor/cgi-bin/Disease_Search.php?lng=EN&data_id=14727&Disease_Disease_Search_diseaseGroup=romano&Disease_Disease_Search_diseaseType=Pat&Disease(s)/group%20of%20diseases=Romano-Ward-syndrome&title=Romano-Ward-syndrome&search=Disease_Search_Simple. Updated: October 1, 2009. Accessed: December 6, 2017.
  7. Fazio G, Vernuccio F, Grutta G, Re GL. Drugs to be avoided in patients with long QT syndrome: Focus on the anaesthesiological management. World J Cardiol. 2013; 5 (4): p.87-93. doi: 10.4330/wjc.v5.i4.87 . | Open in Read by QxMD
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  9. Thomas SHL, Behr ER. Pharmacological treatment of acquired QT prolongation and torsades de pointes. Br J Clin Pharmacol. 2015; 81 (3): p.420-427. doi: 10.1111/bcp.12726 . | Open in Read by QxMD
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  11. Berul CI. Acquired Long QT Syndrome: Definitions, Causes, and Pathophysiology. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/acquired-long-qt-syndrome .Last updated: January 3, 2018. Accessed: December 6, 2017.
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  15. Halawa A, Dave I, Gautam S. Torsade de Pointes with severe vitamin D deficiency, an unusual presentation of a common problem. Journal of Cardiology Cases. 2019; 20 (4): p.132-134. doi: 10.1016/j.jccase.2019.07.003 . | Open in Read by QxMD
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