The idiopathic short QT syndrome (SQTS) is a recently identified condition 
characterized by abbreviated QT intervals (typically 300 ms or less) and in 
affected families is associated with an increased incidence of atrial and 
ventricular arrhythmias and sudden cardiac death. Genetic analysis has, to date, 
identified three distinct forms of the condition, involving gain-of-function 
mutations to three different cardiac potassium channel genes: KCNH2 (SQT1), 
KCNQ1 (SQT2) and KCNJ2 (SQT3). This article reviews recent advances in 
understanding this syndrome, discussing the basis of QT interval shortening, 
possible mechanisms for the associated arrhythmogenic risk in SQT1, current 
approaches to treatment of the SQTS (focusing on SQT1) and avenues for future 
investigation.