Must every child with long QT syndrome take a beta blocker?

Arch Dis Child. 2014 Sep 30. pii: archdischild-2014-306864. doi: 10.1136/archdischild-2014-306864. [Epub ahead of print] Waddell-Smith KE, Earle N, Skinner JR.

Abstract

Long QT syndrome is the most commonly recognised cause of sudden cardiac death in children. With a prevalence of 1 in 2000, family screening is identifying large numbers of hitherto asymptomatic gene carriers in the community, about a third of whom have a normal QT interval. The mainstay of treatment is long term uninterrupted beta blocker therapy, a treatment with many potential side effects. This article reviews the evidence and suggests a cohort who may, after assessment in a specialised cardiac-genetic clinic, be spared this treatment because of very low baseline risk. These are asymptomatic boys and prepubertal girls with a heart rate corrected QT interval persistently less than 470 ms who do not indulge in high risk activities (especially swimming) and do not have a missense mutation in the c-loop region of the KCNQ1 (long QT 1) gene.

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KEYWORDS:
Genetics; beta blockers; children; long QT syndrome; sudden cardiac death