Article

Long QT Syndrome and Pregnancy

University of Rochester, Rochester, New York, United States
Journal of the American College of Cardiology (Impact Factor: 16.5). 03/2007; 49(10):1092-8. DOI: 10.1016/j.jacc.2006.09.054
Source: PubMed

ABSTRACT

This study was designed to investigate the clinical course of women with long QT syndrome (LQTS) throughout their potential childbearing years.
Only limited data exist regarding the risks associated with pregnancy in women with LQTS.
The risk of experiencing an adverse cardiac event, including syncope, aborted cardiac arrest, and sudden death, during and after pregnancy was analyzed for women who had their first birth from 1980 to 2003 (n = 391). Time-dependent Kaplan-Meier and Cox proportional hazard methods were used to evaluate the risk of cardiac events during different peripartum periods.
Compared with a time period before a woman's first conception, the pregnancy time was associated with a reduced risk of cardiac events (hazard ratio [HR] 0.28, 95% confidence interval [CI] 0.10 to 0.76, p = 0.01), whereas the 9-month postpartum time had an increased risk (HR 2.7, 95% CI 1.8 to 4.3, p < 0.001). After the 9-month postpartum period, the risk was similar to the period before the first conception (HR 0.91, 95% CI 0.55 to 1.5, p = 0.70). Genotype analysis (n = 153) showed that women with the LQT2 genotype were more likely to experience a cardiac event than women with the LQT1 or LQT3 genotype. The cardiac event risk during the high-risk postpartum period was reduced among women using beta-blocker therapy (HR 0.34, 95% CI 0.14 to 0.84, p = 0.02).
Women with LQTS have a reduced risk for cardiac events during pregnancy, but an increased risk during the 9-month postpartum period, especially among women with the LQT2 genotype. Beta-blockers were associated with a reduction in cardiac events during the high-risk postpartum time period.

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Available from: Silvia G Priori, Jan 03, 2014
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    • "It is also mentioned that, in women with the congenital LQTS, the risk of cardiac arrest is greater during the post-partum period in comparison with before or during pregnancy10111213. Compared with the pre-conception time period , the postpartum period presents a 2.7-fold increased risk of experiencing a cardiac event and a 4.1-fold increased risk of experiencing a life-threatening event [15]. In contrast, other authors state that women are less prone to arrhythmias during pregnancy although they commonly complain of palpitations, which are sometimes related to the increase in heart rate during pregnancy [16]. "
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    • "In general, lethality of cardiac events seems to be predominant in LQTS3 patients than in LQTS1 and LQTS2 patients (91). Women with LQTS have a reduced risk for cardiac events during pregnancy, but the risk quite increases during the 9-month postpartum period, specially in the women with mutation in the KCNH2 gene (92). "
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    • "It is not yet known why the postpartum period and the perimenopausal period are associated with increased arrhythmogenicity only in LQT2 (and not for example in LQT1). However, β-blockers reduce the risk for cardiac events during these high-risk periods (Seth et al. 2007; Buber et al. 2011). "
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