All LQT3 patients need an ICD: True or false?

Abstract

The identification of the 3 major genetic subtypes of the congenital long QT syndrome (LQTS) has rapidly impacted on clinical management. 1 Schwartz P.J. The congenital long QT syndromes from genotype to phenotype: clinical implications. J Intern Med. 2006; 259: 39-47 Crossref PubMed Scopus (187) Google Scholar Positive examples include the concepts and data related to gene-specific therapy, 1 Schwartz P.J. The congenital long QT syndromes from genotype to phenotype: clinical implications. J Intern Med. 2006; 259: 39-47 Crossref PubMed Scopus (187) Google Scholar , 2 Schwartz P.J. Priori S.G. Locati E.H. et al. Long QT syndrome patients with mutations of the SCN5A and HERG genes have differential responses to Na+ channel blockade and to increases in heart rate Implications for gene-specific therapy. Circulation. 1995; 92: 3381-3386 Crossref PubMed Scopus (712) Google Scholar to gene-specific natural history, 3 Zareba W. Moss A.J. Schwartz P.J. et al. International Long-QT Syndrome Registry Research GroupInfluence of genotype on the clinical course of the long-QT syndrome International Long-QT Syndrome Registry Research Group. N Engl J Med. 1998; 339: 960-965 Crossref PubMed Scopus (659) Google Scholar to gene-specific triggers, 4 Schwartz P.J. Priori S.G. Spazzolini C. et al. Genotype-phenotype correlation in the long-QT syndrome: gene-specific triggers for life-threatening arrhythmias. Circulation. 2001; 103: 89-95 Crossref PubMed Scopus (1450) Google Scholar and to gene-specific 5 Priori S.G. Schwartz P.J. Napolitano C. et al. Risk stratification in the long-QT syndrome. N Engl J Med. 2003; 348: 1866-1874 Crossref PubMed Scopus (1184) Google Scholar and mutation-specific 6 Moss A.J. Zareba W. Kaufman E.S. 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 Crossref PubMed Scopus (326) Google Scholar , 7 Moss A.J. Shimizu W. Wilde A.A. et al. Clinical aspects of type-1 long-QT syndrome by location, coding type, and biophysical function of mutations involving the KCNQ1 gene. Circulation. 2007; 115: 2481-2489 Crossref PubMed Scopus (352) Google Scholar , 8 Crotti L. Spazzolini C. Schwartz P.J. et al. The common long QT syndrome mutation KCNQ1/A341V causes unusually severe clinical manifestations in patients with different ethnic backgrounds: toward a mutation-specific risk stratification. Circulation. 2007; 116: 2366-2375 Crossref PubMed Scopus (139) Google Scholar risk stratification.