gms | German Medical Science

33rd International Congress on Electrocardiology

International Society of Electrocardiology

The Analysis Of Structure Of Sudden Cardiac Death In Families With Different Molecular - Genetic Variants Of Inherited Long Qt Syndrome

Meeting Abstract

  • corresponding author presenting/speaker S. Chuprova - Russian Center for Children`s Arrythmias, Moscow, Russland
  • E. Zaklyazminskaya - Research Center of Medical Genetics, Moscow, Russland
  • M. Shkolnikova - Russian Center for Children’s Arrhythmias, Moscow, Russland

33rd International Congress on Electrocardiology. Cologne, 28.06.-01.07.2006. Düsseldorf, Köln: German Medical Science; 2007. Doc06ice128

The electronic version of this article is the complete one and can be found online at:

Published: February 8, 2007

© 2007 Chuprova et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



The aim of this study: to conduct analyses and detect peculiarities of a structure of SCD in families (fam.) with various molecular-genetic variants of LQTS.

Materials and methods: 70 unrelated Russian fam. with LQTS were clinically evaluated. We tested fam. for mutation (mut.) in 5 genes.

Results: in 46 fam. genetic variant of LQTS was diagnosed: in 58,7% LQT1, in 32,6% LQT2, in 6,5% LQT3 and 2,2% LQT5. From 46 fam. within the affected line 221 persons were examined, the % of the affected - 71,9%. During the observation period (1-15 years) 19,5% of SCD were noted. LQT1-pts with mut. G306R, A344A, A341V and LQT2-pts with mut. A614V, D501Y, T478I and pts with 2 mut. had the most severe phenotype. In 5% cases SCD occurred during the 1st syncope. The largest percentage of SCD (15,4%) was noticed in males with LQT1 at the age of 0-15 years old, and in females with LQT2 at the age of 16-40 years old (29,6%). Concentration of cases with SCD was significantly higher (p<0,001) in pts with LQT2 and LQT3. Among suddenly deceased pts the most frequently observed combination was combination of long QT interval with syncope (76,2%). Against a background of regular intake of beta-blockers SCD occurred in 12,9% pts, at that in most cases in pts with LQT3.

Conclusions: In childhood, the occurrence of SCD was somewhat higher in LQT1-male, but in adulthood, the occurrence of SCD was higher in LQT2-female. Against a background of regular intake of beta-blockers 5,7% pts with LQTS had recurrence of syncope and 12,9% pts suddenly died (in most cases – pts with LQT2 and LQT3, as well as with 2 mut. in one or several genes). LQT1-pts with mut. G306R, A344A, A341V and LQT2-pts with mut. A614V, D501Y, T478I and pts with 2 mut. had the most severe phenotype. SCD in LQT1-pts in equal percentage occurred against a background of physical activity and swimming, and in LQT2-pts in most cases (60%) in rest or in sleep, and in LQT3-pts in sleep (83,3%). Possibility of development of SCD during the 1st syncope in LQTS-pts dictates the necessity of discussion of ICD implantation in asymptomatic pts from fam. with high concentration of SCD and pts with mut. associated with severe phenotype.