Current Treatment Options in Cardiovascular Medicine

, Volume 8, Issue 5, pp 387–395

Congenital long QT syndrome: Diagnosis and management in pediatric patients

  • Yaniv Bar-Cohen
  • Michael J. Silka

Opinion statement

The long QT syndrome (LQTS) is characterized by electrocardiographic abnormalities and a high incidence of syncope and sudden cardiac death (SCD). The diagnosis is suggested when ventricular repolarization abnormalities result in prolongation of the corrected QT interval. When LQTS is suspected, genetic screening may identify a specific long QT subtype and provide guidance for appropriate therapy. Treatment depends on the relative risk of SCD, which is increased with longer QT durations, prior cardiac events, and a family history of SCD. β Blockers are considered the initial treatment of choice, with implantable cardioverter-defibrillator (ICD) therapy warranted in high-risk patients. In patients with frequent ICD shocks or in those at high risk for SCD where ICD placement cannot be performed, cardiac pacing and/or left cardiac sympathetic denervation may be indicated.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References and Recommended Reading

  1. 1.
    Moss AJ: Long QT syndrome. JAMA 2003, 289:2041–2044.PubMedCrossRefGoogle Scholar
  2. 2.
    Shah M, Akar FG, Tomaselli GF: Molecular basis of arrhythmias. Circulation 2005, 112:2517–2529. An excellent summary of the genetics of LQTS is provided in this review.PubMedCrossRefGoogle Scholar
  3. 3.
    Roden DM: Drug-induced prolongation of the QT interval. N Engl J Med 2004, 350:1013–1022.PubMedCrossRefGoogle Scholar
  4. 4.
    Prioro SG, Schwartz PJ, Napolitano C, et al: Risk stratification in the long-QT syndrome. N Engl J Med 2003, 348:1866–1874. This report provides a description of the risks for cardiac events with the major LQTS subtypes.CrossRefGoogle Scholar
  5. 5.
    Goel AK, Berger S, Pelech A, Dhala A: Implantable cardioverter defibrillator therapy in children with long QT syndrome. Pediatr Cardiol 2004, 25:370–378.PubMedCrossRefGoogle Scholar
  6. 6.
    Moss AJ, Robinson JL, Gessman L, et al: Comparison of clinical and genetic variables of cardiac events associated with loud noise versus swimming among subjects with the long QT syndrome. Am J Cardiol 1999, 84:876–879.PubMedCrossRefGoogle Scholar
  7. 7.
    Zareba W, Moss AJ, Schwartz PJ, et al: Influence of genotype on the clinical course of the long-QT syndrome. N Engl J Med 1998, 339:960–965.PubMedCrossRefGoogle Scholar
  8. 8.
    Splawski I, Shen J, Timothy KW, et al: Spectrum of mutations in long-QT syndrome genes KVLQT1, HERG, SCN5A, KCNE1, and KCNE. Circulation 2000, 102:1178–1185.PubMedGoogle Scholar
  9. 9.
    Schwartz PJ, Moss AJ, Vincent GM, Crampton RS: Diagnostic criteria for the long QT syndrome. An update. Circulation 1993, 88:782–784.PubMedGoogle Scholar
  10. 10.
    Zareba W, Moss AJ: Long QT syndrome in children. J Electrocardiol 2001, 34(suppl):167–171.PubMedCrossRefGoogle Scholar
  11. 11.
    Malfatto G, Beria G, Sala S, et al: Quantitative analysis of T wave abnormalities and their prognostic implications in the idiopathic long QT syndrome. J Am Coll Cardiol 1994, 23:296–301.PubMedCrossRefGoogle Scholar
  12. 12.
    Zhang L, Timothy KW, Vincent GM, et al: Spectrum of ST-T-wave patterns and repolarization parameters in congenital long-QT syndrome: ECG findings identify genotypes. Circulation 2000, 102:2849–2855.PubMedGoogle Scholar
  13. 13.
    Seslar SP, Zimetbaum P, Berul CI, Josephson ME: Diagnosis of congenital long QT syndrome. 2006 UpTo-Date. Available at Accessed February 16, 2006.Google Scholar
  14. 14.
    Nemec J, Ackerman MJ, Tester DJ, et al: Catecholamineprovoked microvoltage T wave alternans in genotyped long QT syndrome. Pacing Clin Electrophysiol 2003, 26:1660–1667.PubMedCrossRefGoogle Scholar
  15. 15.
    Napolitano C, Priori SG, Schwartz PJ: Significance of QT dispersion in the long QT syndrome. Prog Cardiovasc Dis 2000, 42:345–350.PubMedCrossRefGoogle Scholar
  16. 16.
    vanden Berg MP, Haaksma J, Veeger NJ, Wilde AA: Diurnal variation of ventricular repolarization in a large family with LQT3-Brugada syndrome characterized by nocturnal sudden death. Heart Rhythm 2006, 3:290–295.PubMedCrossRefGoogle Scholar
  17. 17.
    Garson A Jr, Dick M 2nd, Fournier A, et al: The long QT syndrome in children. An international study of 287 patients. Circulation 1993, 87:1866–1872.PubMedGoogle Scholar
  18. 18.
    Christiansen JL, Guccione P, Garson A Jr: Difference in QT interval measurement on ambulatory ECG compared with standard ECG. Pacing Clin Electrophysiol 1996, 19:1296–1303.PubMedCrossRefGoogle Scholar
  19. 19.
    Dillenburg RF, Hamilton RM: Is exercise testing useful in identifying congenital long QT syndrome? Am J Cardiol 2002, 89:233–236.PubMedCrossRefGoogle Scholar
  20. 20.
    Takenaka K, Ai T, Shimizu W, et al: Exercise stress test amplifies genotype-phenotype correlation in the LQT1 and LQT2 forms of the long-QT syndrome. Circulation 2003, 107:838–844.PubMedCrossRefGoogle Scholar
  21. 21.
    Tester DJ, Will ML, Haglund CM, Ackerman MJ: Effect of clinical phenotype on yield of long QT syndrome genetic testing. J Am Coll Cardiol 2006, 47:764–768.PubMedCrossRefGoogle Scholar
  22. 22.
    Moss AJ, Zareba W, Hall WJ, et al: Effectiveness and limitations of beta-blocker therapy in congenital long-QT syndrome. Circulation 2000, 101:616–623.PubMedGoogle Scholar
  23. 23.
    Priori SG, Napolitano C, Schwartz PJ, et al: Association of long QT syndrome loci and cardiac events among patients treated with beta-blockers. JAMA 2004, 292:1341–1344.PubMedCrossRefGoogle Scholar
  24. 24.
    Khan IA, Gowda RM: Novel therapeutics for treatment of long-QT syndrome and torsade de pointes. Int J Cardiol 2004, 95:1–6.PubMedCrossRefGoogle Scholar
  25. 25.
    Zareba W, Moss AJ, Daubert JP, et al: Implantable cardioverter defibrillator in high-risk long QT syndrome patients. J Cardiovasc Electrophysiol 2003, 14:337–341.PubMedCrossRefGoogle Scholar
  26. 26.
    Stephenson EA, Batra AS, Knilans TK, et al: A multicenter experience with novel implantable cardioverter defibrillator configurations in the pediatric and congenital heart disease population. J Cardiovasc Electrophysiol 2006, 17:41–46.PubMedCrossRefGoogle Scholar
  27. 27.
    Stephenson EA, Cecchin F, Walsh EP, Berul CI: Utility of routine follow-up defibrillator threshold testing in congenital heart disease and pediatric populations. J Cardiovasc Electrophysiol 2005, 16:69–73.PubMedCrossRefGoogle Scholar
  28. 28.
    DeMaso DR, Lauretti A, Spieth L, et al: Psychosocial factors and quality of life in children and adolescents with implantable cardioverter-defibrillators. Am J Cardiol 2004, 93:582–587.PubMedCrossRefGoogle Scholar
  29. 29.
    Schwartz PJ: QT prolongation, sudden death, and sympathetic imbalance: the pendulum swings. J Cardiovasc Electrophysiol 2001, 12:1074–1077.PubMedCrossRefGoogle Scholar
  30. 30.
    Schwartz PJ, Priori SG, Cerrone M, et al: Left cardiac sympathetic denervation in the management of highrisk patients affected by the long-QT syndrome. Circulation 2004, 109:1826–1833.PubMedCrossRefGoogle Scholar
  31. 31.
    Moss AJ, Zareba W: Long QT syndrome: therapeutic considerations. In Cardiac Electrophysiology: From Cell to Bedside, edn 4. Edited by Zipes DP, Jalife J. Philadelphia: WB Saunders; 2004:660–667.Google Scholar
  32. 32.
    Li C, Hu D, Shang L, et al: Surgical left cardiac sympathetic denervation for long QT syndrome: effects on QT interval and heart rate. Heart Vessels 2005, 20:137–141.PubMedCrossRefGoogle Scholar
  33. 33.
    Wang L, Feng G: Left cardiac sympathetic denervation as the first-line therapy for congenital long QT syndrome. Med Hypotheses 2004, 63:438–441.PubMedCrossRefGoogle Scholar
  34. 34.
    Viskin S, Glikson M, Fish R, et al: Rate smoothing with cardiac pacing for preventing torsade de pointes. Am J Cardiol 2000, 86:111K-115K.PubMedCrossRefGoogle Scholar
  35. 35.
    Dorostkar PC, Eldar M, Belhassen B, Scheinman MM: Long-term follow-up of patients with long-QT syndrome treated with beta-blockers and continuous pacing. Circulation 1999, 100:2431–2436.PubMedGoogle Scholar
  36. 36.
    Gregoratos G, Abrams J, Epstein AE, et al: ACC/AHA/ NASPE 2002 guideline update for implantation of cardiac pacemakers and antiarrhythmia devices: summary article. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (ACC/AHA/NASPE Committee to Update the 1998 Pacemaker Guidelines). Circulation 2002, 106:2145–2161.PubMedCrossRefGoogle Scholar
  37. 37.
    Pinski SL, Eguia LE, Trohman RG: What is the minimal pacing rate that prevents torsades de pointes? Insights from patients with permanent pacemakers. Pacing Clin Electrophysiol 2002, 25:1612–1615.PubMedCrossRefGoogle Scholar
  38. 38.
    Etheridge SP, Compton SJ, Tristani-Firouzi M, Mason JW: A new oral therapy for long QT syndrome: long-term oral potassium improves repolarization in patients with HERG mutations. J Am Coll Cardiol 2003, 42:1777–1782.PubMedCrossRefGoogle Scholar

Copyright information

© Current Science Inc 2006

Authors and Affiliations

  • Yaniv Bar-Cohen
    • 1
  • Michael J. Silka
  1. 1.Department of Pediatrics, Division of CardiologyChildren’s Hospital Los AngelesLos AngelesUSA

Personalised recommendations