The SQTS is a rare, sporadic, or autosomal dominant disorder characterized by markedly accelerated cardiac repolarization and manifested by dramatically shortened QT interval, atrial and ventricular arrhythmias, and sudden cardiac death. To date, mutations in potassium (KCNH2 , KCNQ1 , KCNJ2) and calcium channel subunit genes have been identifi ed as causing SQTS. The clinical manifestations of this disorder have been characterized in a relatively small number of families and sporadic individuals, given the recent identifi cation and rare nature of SQTS.
SQTS is defined (Gollob, 2006) as a QTc interval ≤ 340 ms or QTc interval between 341 ms and 360 ms and 1 or more of the following: history of CA or syncope, a family history of unexplained CA at a young age (40 years of age or younger), or a family history of SQTS.
The QTp was calculated using the formula developed by
Rautaharju et al. : [QTp = 656/(1 + heart rate/100)]
Plus le QTc est court plus le risque d’arythmie augmente (ex. QTc très court < 320 ms)
Gollob MH, Redpath CJ, Roberts JD. The short QT syndrome: proposed diagnostic criteria. J Am Coll Cardiol. 2011 Feb 15;57(7):802-12.
Mazzanti A, Kanthan A, Monteforte N, et al. Novel insight into the natural history of short QT syndrome. J Am Coll Cardiol. 2014 Apr 8;63(13):1300-8.
–> In this study, we showed that having survived a first occurrence of CA is a strong predictor of recurrences. This information is important because it supports the need to consider implanting an ICD for secondary prevention of CA even in young SQTS patients.