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Short QT: when does it matter?

For half a century, the relationship between the QT interval and cardiac arrhythmias has been recognized,1 although attention has focused primarily on prolongation of the QT. The congenital long-QT syndrome (LQTS) was first identified in patients with syncope, aborted sudden death, or family history of cardiac arrest as an association between a prolonged QT interval and development of potentially fatal polymorphic ventricular tachycardia (torsade de pointes).2,3 Further research has resulted in the identification of a number of etiologic inherited ion channelopathies, and criteria have been defined to allow diagnosis and evaluation of risk based on the QT interval.4 Only in recent years has attention been paid to short QT intervals with the recent discovery of a familial syndrome characterized by short QT interval and sudden death (the short QT syndrome [SQTS]). In this issue of Circulation, Anttonen et al5 add to our understanding of the frequency of a short QT interval and prognosis in a general population.