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Sudden cardiac death without structural heart disease: Update on the long QT and brugada syndromes

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Abstract

The long QT syndrome (LQTS) and the Brugada syndrome (BrS) are the most common genetic causes of malignant ventricular arrhythmias and sudden cardiac death in young patients with normal cardiac morphology. To date, more than 250 different mutations in seven genes have been identified as causing LQTS, whereas the only gene identified to be linked to BrS is SCN5A. In both syndromes, genespecific mutations have been shown to be associated with specific phenotypic expressions. Risk stratification in LQTS and BrS is based mainly upon a constellation of electrocardiographic findings and a history of prior symptoms. In patients identified as high risk for arrhythmic mortality, the implantable cardioverter defibrillator is the most effective treatment and has been shown to provide near-complete protection during long-term follow-up.

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References and Recommended Reading

  1. Splawski I, Shen J, Timothy KW, et al.: Spectrum of mutations in long-QT syndrome genes KVLQT1, HERG, SCN5A, KCNE1, and KCNE2. Circulation 2000, 102:1178–1185.

    PubMed  CAS  Google Scholar 

  2. Wang Q, Shen J, Splawski I, et al.: SCN5A mutations associated with an inherited cardiac arrhythmia, long QT syndrome. Cell 1995, 80:805–811.

    Article  PubMed  CAS  Google Scholar 

  3. Sanguinetti MC, Jiang C, Curran ME, et al.: 1995. A mechanistic link between an inherited and an acquired cardiac arrhythmia: HERG encodes the IKr potassium channel. Cell 1995, 81:299–307.

    Article  PubMed  CAS  Google Scholar 

  4. Wang Q, Curran ME, Splawski I, et al.: Positional cloning of a novel potassium channel gene: KVLQT1 mutations cause cardiac arrhythmias. Nat Genet 1996, 12:17–23.

    Article  PubMed  Google Scholar 

  5. Westenskow P, Splawski I, Timothy KW, et al.: Compound mutations: a common cause of severe long-QT syndrome. Circulation 2004, 109:1834–1841. The paper shows that LQTS-associated compound mutations cause a severe phenotype and are more common than expected.

    Article  PubMed  Google Scholar 

  6. Delisle BP, Anson BD, Rajamani S, January CT: Biology of cardiac arrhythmias: ion channel protein trafficking. Circ Res 2004, 94:1418–1428. This review focuses on how heart cells process ion channel proteins and how this protein trafficking may be altered in LQTS and BrS.

    Article  PubMed  CAS  Google Scholar 

  7. Chen Q, Kirsch GE, Zhang D, et al.: Genetic basis and molecular mechanisms for idiopathic ventricular fibrillation. Nature 1998, 392:293–296.

    Article  PubMed  CAS  Google Scholar 

  8. Tan HL, Bezzina CR, Smits JP, et al.: Genetic control of sodium channel function. Cardiovasc Res 2003, 57:961–973.

    Article  PubMed  CAS  Google Scholar 

  9. Schulze-Bahr E, Eckardt L, Breithardt G, et al.: Sodium channel gene (SCN5A) mutations in 44 index patients with Brugada syndrome: different incidences in familial and sporadic disease. Hum Mutat 2003, 21:651–652.

    Article  PubMed  CAS  Google Scholar 

  10. Weiss R, Barmada MM, Nguyen T, et al.: Clinical and molecular heterogeneity in the Brugada syndrome: a novel gene locus on chromosome 3. Circulation 2002, 105:707–713.

    Article  PubMed  CAS  Google Scholar 

  11. Moss AJ: T-wave patterns associated with the hereditary long QT syndrome. Card Electrophysiol Rev 2003, 6:311–315.

    Article  Google Scholar 

  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.

    PubMed  CAS  Google Scholar 

  13. Schwartz PJ, Priori SG, Spazzolini C, et al.: Genotype-phenotype correlation in the long-QT syndrome: gene-specific triggers for life-threatening arrhythmias. Circulation 2001, 103:89–95.

    PubMed  CAS  Google Scholar 

  14. Khositseth A, Tester DJ, Will ML, et al.: Identification of a common genetic substrate underlying postpartum cardiac events in congenital long QT syndrome. Heart Rhythm 2004, 1:60–64.

    Article  PubMed  Google Scholar 

  15. 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.

    Article  PubMed  CAS  Google Scholar 

  16. Choi G, Kopplin LJ, Tester DJ, et al.: Spectrum and frequency of cardiac channel defects in swimming-triggered arrhythmia syndromes. Circulation 2004, 110:2119–2124.

    Article  PubMed  Google Scholar 

  17. Zareba W, Moss AJ, Schwartz PJ, et al.: International Long-QT Syndrome Registry Research Group. Influence of genotype on the clinical course of the long-QT syndrome. N Engl J Med 1998, 339:960–965.

    Article  PubMed  CAS  Google Scholar 

  18. Priori SG, Schwartz PJ, Napolitano C, et al.: Risk stratification in the long-QT syndrome. N Engl J Med 2003, 348:1866–1874. The largest series to date correlating the locus of the causative mutation to the clinical course of the long-QT syndrome.

    Article  PubMed  Google Scholar 

  19. 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. This recent study shows that in LQTS patients treated with β-blockers, the rate of cardiac events continues to be high, and is correlated to the LQTS genotype.

    Article  PubMed  CAS  Google Scholar 

  20. Zareba W, Moss AJ, Locati EH, et al.: International Long QT Syndrome Registry. Modulating effects of age and gender on the clinical course of long QT syndrome by genotype. J Am Coll Cardiol 2003, 42:103–109. An important study, showing that the risk for cardiac events in LQTS is age- and sex-specific.

    Article  PubMed  Google Scholar 

  21. Moss AJ, Zareba W, Kaufman ES, et al.: Increased risk of arrhythmic events in long-QT syndrome with mutations in the pore region of the human ether-a-go-go-related gene potassium channel. Circulation 2002, 105:794–799. The first study in LQTS correlating the location of the mutation in the pathogenic gene correlates to the risk of cardiac events.

    Article  PubMed  CAS  Google Scholar 

  22. Zareba W, Moss AJ, Sheu G, et al.: Location of mutation in the KCNQ1 and phenotypic presentation of long QT syndrome. J Cardiovasc Electrophysiol 2003, 11:1149–1153.

    Article  Google Scholar 

  23. Vincent GM, Timothy KW, Leppert M, et al.: The spectrum of symptoms and QT intervals in carriers of the gene for the long-QT syndrome. N Engl J Med 1992, 327:846–852.

    Article  PubMed  CAS  Google Scholar 

  24. Napolitano C, Schwartz PJ, Brown AM, et al.: Evidence for a cardiac ion channel mutation underlying drug-induced QT prolongation and life-threatening arrhythmias. J Cardiovasc Electrophysiol 2000, 11:691–696.

    Article  PubMed  CAS  Google Scholar 

  25. Horigome H, Shigeta O, Kuga K, et al.: Ventricular fibrillation during anesthesia in association with J waves in the left precordial leads in a child with coarctation of the aorta. J Electrocardiol 2003, 36:339–343.

    Article  PubMed  Google Scholar 

  26. Potet F, Mabo P, Le Coq G, et al.: Novel brugada SCN5A mutation leading to ST segment elevation in the inferior or the right precordial leads. J Cardiovasc Electrophysiol 2003, 14:200–203.

    Article  PubMed  Google Scholar 

  27. Di Diego JM, Cordeiro JM, Goodrow RJ, et al.: Ionic and cellular basis for the predominance of the Brugada syndrome phenotype in males. Circulation 2002, 106:2004–2011.

    Article  Google Scholar 

  28. Smits JP, Eckardt L, Probst V, et al.: Genotype-phenotype relationship in Brugada syndrome: electrocardiographic features differentiate SCN5A-related patients from non-SCN5A-related patients. J Am Coll Cardiol 2002, 40:350–356.

    Article  PubMed  CAS  Google Scholar 

  29. Mizumaki K, Fujiki A, Tsuneda T, et al.: Vagal activity modulates spontaneous augmentation of ST elevation in the daily life of patients with Brugada syndrome. J Cardiovasc Electrophysiol 2004, 15:667–673.

    Article  PubMed  Google Scholar 

  30. Bezzina C, Veldkamp MW, van Den Berg MP, et al.: A single Na+ channel mutation causing both long-QT and Brugada syndromes. Circ Res 1999, 85:1206–1213.

    PubMed  CAS  Google Scholar 

  31. Grant AO, Carboni MP, Neplioueva V, et al.: A spontaneous mutation identifies a residue critical for closed-state inactivation of cardiac sodium channels [abstract]. Circulation 2001, 104(Suppl II):II-310.

    Google Scholar 

  32. Schwartz J, Moss AJ, Vincent GM, Crampton RS: Diagnostic criteria for the long QT syndrome: an update. Circulation 1993, 88:782–784.

    PubMed  CAS  Google Scholar 

  33. Zareba W, Moss AJ, Daubert JP, et al.: Arrhythmic events in LQTS patients with implantable cardioverter defibrillators [abstract]. Heart Rhythm 2004, 1(Suppl 1):532.

    Google Scholar 

  34. Antzelevitch C, Brugada P, Borggrefe M, et al.: Brugada syndrome: report of the second consensus conference: endorsed by the Heart Rhythm Society and the European Heart Rhythm Association. Circulation 2005, 111:659–670. A recent consensus report on BrS summarizing diagnostic criteria, risk stratification schemes, and device and pharmacologic approaches to therapy.

    Article  PubMed  Google Scholar 

  35. Brugada J, Brugada R, Antzelevitch C, et al.: Long-term followup of individuals with the electrocardiographic pattern of right bundle-branch block and ST-segment elevation in precordial leads V1 to V3. Circulation 2002, 105:73–78. A retrospective analysis of 334 BrS patients suggesting that risk stratification for arrhythmic events should be based upon ECG parameters, the presence of symptoms, and inducibility to ventricular arrhythmias during programmed electrical stimulation.

    Article  PubMed  Google Scholar 

  36. Priori SG, Napolitano C, Gasparini M, et al.: Natural history of Brugada syndrome: insights for risk stratification and management. Circulation 2002, 105:1342–1347. A retrospective analysis of 200 BrS patients conflicting the data by Brugada et al. [35•] that inducibility to ventricular arrhythmias during programmed electrical stimulation is associated with increased risk to subsequent spontaneous ventricular fibrillation.

    Article  PubMed  Google Scholar 

  37. Eckardt L, Probst V, Smits JP, et al.: Long-term prognosis of individuals with right precordial ST-segment-elevation Brugada syndrome. Circulation 2005, 111:257–263.

    Article  PubMed  Google Scholar 

  38. Kanda M, Shimizu W, Matsuo K, et al.: Electrophysiologic characteristics and implications of induced ventricular fibrillation in symptomatic patients with Brugada syndrome. J Am Coll Cardiol 2002, 39:1799–1805.

    Article  PubMed  Google Scholar 

  39. Eckardt L, Kirchhof P, Schulze-Bahr E, Rolf S, et al.: Electrophysiologic investigation in Brugada syndrome; yield of programmed ventricular stimulation at two ventricular sites with up to three premature beats. Eur Heart J 2002, 23:1394–1401.

    Article  PubMed  CAS  Google Scholar 

  40. Schwartz PJ, Priori SG, Spazzolini C, et al.: Genotype-phenotype correlation in the long-QT syndrome: gene-specific triggers for life-threatening arrhythmias. Circulation 2001, 103:89–95.

    PubMed  CAS  Google Scholar 

  41. 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.

    PubMed  CAS  Google Scholar 

  42. Nalbantgil I, Moss AJ: Sympathetic ganglionectomy for treatment of long-QT-interval syndrome. N Engl J Med 1972, 286:607.

    Google Scholar 

  43. Schwartz PJ, Priori SG, Cerrone M, et al.: Left cardiac sympathetic denervation in the management of high-risk patients affected by the long-QT syndrome. Circulation 2004, 109:1826–1833.

    Article  PubMed  Google Scholar 

  44. Dorostkar PC, Eldar M, Beihassen 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.

    PubMed  CAS  Google Scholar 

  45. Haissaguerre M, Extramiana F, Hocini M, et al.: Mapping and ablation of ventricular fibrillation associated with long-QT and Brugada syndromes. Circulation 2003, 108:925–928.

    Article  PubMed  Google Scholar 

  46. 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. A retrospective analysis of 125 high-risk LQTS patients showing that the implantable defibrillator is effective in the prevention of arrhythmic mortality in this population.

    Article  PubMed  Google Scholar 

  47. Goel AK, Berger S, Pelech A, Dhala A: Implantable cardioverter defibrillator therapy in children with long QT syndrome. Pediatr Cardiol 2004, 4:370–378.

    Google Scholar 

  48. Khan IA, Gowda RM: Novel therapeutics for treatment of long-QT syndrome and torsade de pointes. Int J Cardiol 2004, 95:1–6.

    Article  PubMed  CAS  Google Scholar 

  49. Alings M, Dekker L, Sadee A Wilde A: Quinidine induced electrocardiographic normalization in two patients with Brugada syndrome. Pacing Clin Electrophysiol 2001, 24:1420–1422.

    Article  PubMed  CAS  Google Scholar 

  50. Hermida JS, Denjoy I, Clerc J, et al.: Hydroquinidine therapy in Brugada syndrome. J Am Coll Cardiol 2004, 43:1853–1860.

    Article  PubMed  CAS  Google Scholar 

  51. Beihassen B, Glick A, Viskin S: Efficacy of quinidine in high-risk patients with Brugada syndrome. Circulation 2004, 110:1731–1737. A nonrandomized retrospective analysis of 25 high-risk BrS patients who were treated with quinidine, showing, during a long-term follow-up, that the drug was effective in the long-term prevention of arrhythmic events in this population.

    Article  Google Scholar 

  52. Tsuchiya T, Ashikaga K, Honda T, Arita M: Prevention of ventricular fibrillation by cilostazol, an oral phosphodiesterase inhibitor, in a patient with Brugada syndrome. J Cardiovasc Electrophysiol 2002, 13:698–701.

    Article  PubMed  Google Scholar 

  53. Antzelevitch C: The Brugada syndrome: ionic basis and arrhythmia mechanisms. J Cardiovasc Electrophysiol 2001, 12:268–272.

    Article  PubMed  CAS  Google Scholar 

  54. Brugada J, Brugada R, Brugada P: Pharmacological and device approach to therapy of inherited cardiac diseases associated with cardiac arrhythmias and sudden death. J Electrocardiol 2000, 33:41–47.

    Article  PubMed  Google Scholar 

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Goldenberg, I., Moss, A.J. & Zareba, W. Sudden cardiac death without structural heart disease: Update on the long QT and brugada syndromes. Curr Cardiol Rep 7, 349–356 (2005). https://doi.org/10.1007/s11886-005-0088-1

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