Skip to
  1. Homepage
  2. Rare diseases
  3. Search
Simple search

Simple search

(*) mandatory field


Other search option(s)

Familial short QT syndrome

Synonym(s) SQTS
Prevalence Unknown
Inheritance Autosomal dominant
Age of onset All ages
  • I49.8
MeSH -
MedDRA -


Disease definition

Familial short QT syndrome is a newly described cardiologic entity that associates a short QT interval (QT and QTc 300 ms) on the surface electrocardiogram (ECG) with a high risk of syncope or sudden death due to malignant ventricular arrhythmia.


This extremely rare syndrome affects mainly young adults or infants.

Clinical description

The clinical spectrum is very wide ranging from asymptomatic carriers to syncope or sudden death. It is frequently associated with atrial fibrillation.


Mutations in three different genes KCNQ1, KCNH2, and KCNJ2, all encoding cardiac ionic potassium channels have been identified in affected patients.

Diagnostic methods

Expression studies have shown a gain of function and a shortening of the action potential duration, explaining the short QT interval. At electrophysiologic study, atrial and ventricular refractory periods are short, and ventricular fibrillation is inducible in the majority of patients.

Genetic counseling

Transmission is autosomal dominant.

Management and treatment

At present, an automatic implantable defibrillator is the only effective treatment for the prevention of sudden death in the short QT syndrome.

Expert reviewer(s)

  • Dr Isabelle DENJOY
  • Dr Jean-Marc LUPOGLAZOFF

(*) Required fields.

Attention: Only comments seeking to improve the quality and accuracy of information on the Orphanet website are accepted. For all other comments, please send your remarks via contact us. Only comments written in English can be processed.

Captcha image

Detailed information

Review article
Clinical practice guidelines
Get Acrobat Reader
The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.