Short QT Syndrome


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Short QT Publications

Click here to find an updated list of Short QT Syndrome publications that includes a description of each publications content.
Last update: May 2014


Distribution of the first 100 reported cases of Short QT Syndrome
as of  May, 2014:

Countries where patients with Short QT Syndrome have been found:

USA, Italy, Spain, The Netherlands, Germany, France, Finland, Brazil, Turkey and China


Physicians Section


Patients Section


NEWS October, 2008

At the Heart Rhythm Society Meeting in San Francisco, California USA, May-2008, Preben Bjerregaard, MD, presented the following abstract:  

 

Upper limits of QT/QTc Interval in the Short QT Syndrome.

Review of the World-Wide Short QT Syndrome Population and 3 New USA Families.

 

*Preben Bjerregaard, MD, DMSc, *Jack L. Collier, MD and **Ihor Gussak, MD, PhD, *VA Medical Center, Saint Louis, MO and **Boehringer-Ingelheim Pharmaceuticals, Inc., Ridgefield, CT

 

Introduction: Short QT Syndrome (SQTS) is a channelopathy with a high risk of sudden cardiac death (SCD), characterized by a short QT interval and a propensity to atrial and ventricular tachy-arrhythmias. In few families a mutation has been found either in the KCNH2, KCNQ1 or KCNJ2 gene. The upper limit for QT/QTc in patients with SQTS is unknown, but current research papers suggest a range of 300-330 msec.

Aim: Based upon world-wide families with known SQTS and incidental patients discovered within our investigation, we sought to address the question: What is the upper cutoff point for QT/QTc in patients with SQTS?

Patients: Adding previously unpublished data from 8 individuals in 3 USA families with SQTS increased the total number of those with an ECG documented short QT interval in the setting of SQTS to 53 (21 Female, 32 Male). Two of the patients are babies born with atrial fibrillation (AFIB). It represents a total of 14 families and 9 sporadic patients with known SQTS from 10 different countries. A total of 16 had a history of SCD/aborted SCD, 27 had a family history of SCD/aborted SCD, 8 had atrial fibrillation only and 2 (both from the same family) had a genetic mutation (KCNJ2), but no symptoms.

QT, heart rate (HR) and QTcs (Bazetts formula) were obtained from published reports except for the new patients, where they were measured in the first ECG available.

Results: (Excluding two patients with right bundle branch block).

Patient

Categories

N

QT

Msec

Mean 2 SD, Range

HR

Beats/min

Mean, Range

QTc

Msec

Mean 2 SD, Range

Fam. Hx. of SCD

26

291 55#, 240-340

70, 54-90

312 39, 268-345

SCD/Aborted  SCD

16

271 66, 210-315

75, 52-128

298 43, 248-325

AFIB only

  7

265 49, 220-300

73, 54-105

289 46, 283-306

Mutation Positive

  2

 

 

                315-320

TOTAL:

51

282 63, 210-340

72, 52-128

305 42, 248-345

# : p = 0.005 vs patients with SCD or tachy-arrhythmias

Conclusion :  Despite being recognized in at least 10 countries, SQTS remains a rare diagnosis. One likely reason is, that the currently accepted upper limit for QT/QTc in patients with SQTS is too low. Even though patients with SQTS and tachy-arrhythmias have shorter QT intervals than patients without such arrhythmias (vide supra), the implications of our research indicate, that anyone with a QT/QTc below 345 msec and their family be ruled out for SQTS.

 

A detailed description of the 3 new USA families with SQTS:

 

 A detailed description of the QT and QTc intervals in the World-Wide population with SQTS:

 


Last updated: 04/02/2014

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