Dataset Information

Long QT interval in Turner syndrome--a high prevalence of LQTS gene mutations.

ABSTRACT:

Objectives

QT-interval prolongation of unknown aetiology is common in Turner syndrome. This study set out to explore the presence of known long QT mutations in Turner syndrome and to examine the corrected QT-interval (QTc) over time and relate the findings to the Turner syndrome phenotype.

Methods

Adult women with Turner syndrome (n = 88) were examined thrice and 68 age-matched healthy controls were examined once. QTc was measured by one blinded reader (intra-reader variability: 0.7%), and adjusted for influence of heart rate by Bazett's (bQTc) and Hodges's formula (hQTc). The prevalence of mutations in genes related to Long QT syndrome was determined in women with Turner syndrome and a QTc >432.0 milliseconds (ms). Echocardiographic assessment of aortic valve morphology, 24-hour blood pressures and blood samples were done.

Results

The mean hQTc in women with Turner syndrome (414.0 ± 25.5 ms) compared to controls (390.4 ± 17.8 ms) was prolonged (p<0.001) and did not change over time (416.9 ± 22.6 vs. 415.6 ± 25.5 ms; p =0.4). 45,X karyotype was associated with increased hQTc prolongation compared to other Turner syndrome karyotypes (418.2 ± 24.8 vs. 407.6 ± 25.5 ms; p = 0.055). In women with Turner syndrome and a bQTc >432 ms, 7 had mutations in major Long QT syndrome genes (SCN5A and KCNH2) and one in a minor Long QT syndrome gene (KCNE2).

Conclusion

There is a high prevalence of mutations in the major LQTS genes in women with TS and prolonged QTc. It remains to be settled, whether these findings are related to the unexplained excess mortality in Turner women.

Clinical trial registration

NCT00624949. https://register.clinicaltrials.gov/prs/app/action/SelectProtocol/sid/S0001FLI/selectaction/View/ts/3/uid/U000099E.

SUBMITTER: Trolle C

PROVIDER: S-EPMC3723856 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Long QT interval in Turner syndrome--a high prevalence of LQTS gene mutations.

Trolle Christian C Mortensen Kristian H KH Pedersen Lisbeth N LN Berglund Agnethe A Jensen Henrik K HK Andersen Niels H NH Gravholt Claus H CH

PloS one 20130725 7

<h4>Objectives</h4>QT-interval prolongation of unknown aetiology is common in Turner syndrome. This study set out to explore the presence of known long QT mutations in Turner syndrome and to examine the corrected QT-interval (QTc) over time and relate the findings to the Turner syndrome phenotype.<h4>Methods</h4>Adult women with Turner syndrome (n = 88) were examined thrice and 68 age-matched healthy controls were examined once. QTc was measured by one blinded reader (intra-reader variability: 0 ...[more]

PMID: 23936059

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Dataset Information

Long QT interval in Turner syndrome--a high prevalence of LQTS gene mutations.

Objectives

Methods

Results

Conclusion

Clinical trial registration

Publications

Long QT interval in Turner syndrome--a high prevalence of LQTS gene mutations.

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