Impact of Beta-Blocker Therapy on Pregnant Women With Long QT Syndrome: A Systematic Review

Bassel Alrabadi1, Hadeel A Al Kayed2, Nour Alshujaieh3

  • 1Internal Medicine, Al-Balqa Applied University, Al-Salt, JOR.

Cureus
|November 18, 2024
PubMed

Long QT syndrome (LQTS) presents significant challenges for pregnant women due to the elevated risk of arrhythmic events. Beta-blocker therapy is a cornerstone of treatment in managing LQTS, but its use during pregnancy introduces potential fetal risks. This systematic review synthesizes the evidence on the efficacy and safety of beta-blocker therapy in pregnant women with LQTS. A systematic review was conducted to assess studies on beta-blocker use in pregnant women diagnosed with LQTS. We reviewed observational studies and case reports to evaluate maternal cardiac outcomes, fetal safety, and the need for postpartum management. Studies were selected based on inclusion criteria focused on LQTS, beta-blocker therapy during pregnancy, and associated maternal and fetal outcomes. Our review showed that beta-blocker therapy significantly reduced arrhythmic events in pregnant women with LQTS, particularly in symptomatic carriers. Multiple studies demonstrated that the continuation of beta-blocker therapy throughout pregnancy and the postpartum period minimized maternal cardiac risks. However, beta-blocker use was associated with fetal risks such as intrauterine growth restriction (IUGR), lower birth weight, and, in some cases, bradycardia. Atenolol, in particular, was linked to significant fetal growth restrictions, while other beta-blockers, such as propranolol and metoprolol, showed more variable effects on fetal outcomes. Despite these concerns, some studies reported favorable postnatal growth recovery in infants exposed to beta-blockers in utero. Beta-blocker use must be carefully managed due to potential fetal risks. Regular monitoring, individualized treatment plans, and appropriate selection of beta-blocker type are essential to optimizing both maternal and fetal outcomes. Further research is necessary to refine treatment protocols and reduce fetal risks associated with beta-blocker therapy during pregnancy.

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