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REFERENCES TO ARTICLES ABOUT SHORT QT SYNDROME
1999
1. Gussak I, Liebl N,
Nouri S, Bjerregaard P, Zimmerman F, Chaitman BR.
Deceleration-Dependent
Shortening of the QT Interval: A New Electrocardiographic Phenomenon?
Clin Cardiol
1999;22:124-126
Case report describing a 4 year old
African-American girl with complications related to premature birth,
developmental delay and recurrent episodes of cardiac arrest with brady-arrhythmias.
An episode documented electrocardiographically showed QT-interval
shortening during severe bradycardia.
Activation of the IkACh
channel due to high vagal discharge was proposed as a possible mechanism
responsible for both slowing of the heart rate and shortening of the QT
interval.
The question was raised whether
deceleration-dependent shortening of the QT interval has arrhythmogenic
potential?
2000
2.
Gussak I,
Chaitman BR, Kopecky SL, Nerbonne JM.
Rapid Ventricular
Repolarization in Rodents: Electrocardiographic Manifestations,
Molecular Mechanisms, and Clinical Insights.
J Electrocardiol
2000;33(2):159-170
3.
Gussak I,
Brugada P, Brugada J, Wright RS, Kopecky SL, Chaitman BR,
Bjerregaard P.
Idiopathic Short QT
Interval: A New Clinical Syndrome?
Cardiology 2000;94:99-102
The first report of a family with short QT
interval including a 51 year
old female and her two children, a 17 year old female and a 21
year old male, discovered when the 17 year old female presented with
atrial fibrillation and a QT interval of 280 ms at a heart rate of
69 beats/min.
Adding the story of a 37 year old Spanish
female with sudden cardiac death and a QT interval of 266 ms at a
heart rate of 52 beats/min led to the speculation of a link between
the short QT interval, a short refractory period and electrical
instability which might explain the proclivity to spontaneous
development of atrial and/or ventricular tachyarrhythmias.
The author’s made the suggestion:”If
additional supporting clinical data become available, we believe
that – paralleling the ‘long QT syndrome’ – the combination of short
QT interval and electrical instability could appropriately be named
the ‘short QT interval syndrome’.
2002
4.
Gussak I,
Brugada P, Brugada J, Antzelevich C, Osbakken M, Bjerregaard, P.
ECG Phenomenon of Idiopathic
and Paradoxical Short QT Intervals.
Cardiac Electrophysiology
Review 2002;6:49-53
Discussion of clinical scenarios where a short
QT interval may occur followed by a description of possible
electrophysiologic consequences of a short QT interval.
2003
5.
Gussak I,
Antzelevitch C, Goodman D, Bjerregaard P.
Short QT Interval: ECG
Phenomenon and Clinical Syndrome.
In: Gussak I, Antzelevitch C, Hammill SC, Shen W-K, Bjerregaard P,
editors: Cardiac Repolarization – Bridging Basic and Clinical Science.
2003;497-505
A description of current perspective of a
short QT interval followed by a description of possible
electrophysiological mechanisms and the arrhythmogenic potential.
6.
Gaita F, Giustetto C, Bianchi F, Riccardi R, Grossi S, Richiardi
E.
Short QT: A New
Electrocardiographic Pattern Related to Familial Sudden Death.
JACC 2003;4(Supplement A):
818-3 (Abstract)
Presentation at the ACC meeting in Chicago,
March 2003 of three living members of an Italian family with SCD for
four generations. The subjects presented with a history of palpitations,
syncope or aborted SCD and ECG’s with very short QT intervals (mean
value of 240 ms and mean corrected QT of 290 ms). Organic heart disease
was ruled out and during EP-study easily inducible VF with very short
refractory periods in both atria and ventricles. Flecainide was
shown to increase the refractory periods and make VF no longer
inducible.
This was the first presentation of a family
with both a high incidence of SCD and a high incidence of Short QT in
the ECG, and also the first documentation of cardiac arrest in a
child (at the age of 8 months) with a short QT-interval.
7.
Gaita F, Giustetto C, Bianchi F, Wolpert C, Schrimpf R, Riccardi
R, Grossi S, Richiardi E, Borggrefe M.
Short QT Syndrome. A
Familial Cause of Sudden Death.
Circulation 2003;108:965-970
In this paper the Italian family described at
the ACC meeting is combined with the description of a German family with
very similar story.
A total of six patients from both families
were submitted to serial ECG testing, echocardiography, cardiac MRI,
exercise testing, Holter monitoring and signal-averaged ECG recording.
Four underwent in addition an electrophysiological evaluation including
programmed ventricular stimulation.
None of the patient showed any evidence of
structural heart disease. Baseline ECG showed in all patient a QT
interval </= 280 ms and the EP-study showed very short refractory period
both in the atria and the ventricles with induction of VF by PES in 3 of
the 4 patients (in 2 patients even by catheter manipulation during
placement of the catheters prior to the procedure). Three patients
received an ICD.
This paper had clearly demonstrated the
malignant nature of idiopathic, extremely short QT interval.
8.
Brugada R,
Hong K, Dumaine R, Cordeiro J, Gaita F, Borggrefe M, Menendez TM,
Brugada J, Pollevick GD, Wolpert C, Burachnikov E, Matsuo K, Wu YS,
Guerchicoff A, Bianchi F, Giustetto C, Schrimpf R, Brugada P,
Antzelevich C.
Sudden Death Associated With
Short-QT Syndrome Linked to Mutations in HERG.
Circulation 2004,109:30-35
In this paper genetic testing was performed in
the two families previously described by Gaita et al. in 2003 and in a
family from the US not previously published, consisting of a 51 y.o.
father with aborted SCD and a 20 y.o. son with short QT. In the German
and the Italian family they identified 2 different missense mutations
resulting in the same amino acid change (N588K) in the S5-P loop region
of the cardiac IKr channel HERG (KCNH2). The mutations
dramatically increase IKr , leading to heterogeneous
abbreviation of cardiac action potential duration and refractoriness.
This was the first description of a genetic
abnormality responsible for some cases of SQTS
9. Schrimpf R, Wolpert C,
Bianchi F, Giustetto C, Gaita F, Bauersfeld U, Borggrefe M.
Congenital Short QT Syndrome
and Implantable Cardioverter Defibrillator Treatment: Inherent Risk for
Inappropriate Shock Delivery.
J Cardiovasc Electrophysiol
2003;14:1273-1277
This paper describes the experience of ICD
implantation in 5 patients from the Italian and German families. Due to
T-wave oversensing inappropriate shocks were delivered in 3 patients
shortly after implantation. Programming lower sensitivities and decay
delays prevented further inappropriate discharges.
10. Passman R.
Inappropriate
Inplantable Cardioverter Defibrillator Therapy in the Short QT Syndrome:
Old Problem in a New Disease.
J Cardiovasc Electrophysiol
2003;14:1278-1279
This is an editorial comment to the previous
paper
2004
11.
Zipes DP.
The Year in
Electrophysiology.
JACC 2004;43:1306-1314
A description of the advances in cardiac
electrophysiology during 2003 included a brief (10 lines) description of
SQTS.
12.
Gaita F, Giustetto C, Bianchi F, Schrimpf R, Haissaguerre M, Calo
L, Brugada R, Antzelevitch C, Borggrefe M, Wolpert C.
Short QT Syndrome:
Pharmacological Treatment.
JACC 2004;43:1494-1499
Six members from the previously published
German and Italian families were tested with Flecainide, Sotalol,
Ibutilide and Hydroquinidine. Flecainide, Sotalol and Ibutilide did not
produce any significant QT prolongation. Only hydroquinidine prolonged
the QT interval from 263 +/- 12 msec to 362 +/- 25 msec with
prolongation of the ventricular effective refractory period to > 200
msec and VF no longer inducible. Quinidine was recommended as the drug
of choice for medical therapy while flecainide because of the increase
in the effective refractory period could be the second choice.
13.
Bellocq C, van
Ginneken ACG, Bezzina CR, Alders M, Escande D, Mannens MMAM, Baro I,
Wilde AAM.
Mutation in the KCNQ1
Gene Leading to the Short QT-Interval Syndrome.
Circulation
2004;109:2394-2397
This paper describes a 70
year old male with aborted SCD and a short QT interval. Analysis of
candidate genes identified a g919c substitution in KCNQ1 (V307L
mutation) encoding the K+ channel KvLQT1.
This was the second
description of a genetic defect leading to SQTS
14. Bjerregaard P, Gussak
I.
Atrial Fibrillation in the
Setting of Familial Short QT Syndrome.
Heart Rhythm
2004;1(1S):522
This was a poster presentation of the four
members of the first family with SQTS providing a more detailed
description including the result of Holter monitoring, programmed
electrical stimulation and treatment of atrial fibrillation with
propafenone.
Of special interest was the beneficial effect
of propafenone in treatment of atrial fibrillation without any
effect on the QT interval.
14.
Bellocq C, van
Ginnekan A, Bezzina CR, Alders M, Escanda D, Mannens M. Wilde AA.
Mutation in the KCNQ1 Gene
Leading to the Short-QT-Interval Syndrome.
Circulation 2004;110(17);
III-230
An oral presentation at the
AHA meeting in October 2004 describing what had already been published
in May 2004 (see ref. # 13).
15.
Wolpert C, Schimpf R, Gaita F, Bianchi F, Riccardi R, Borggrefe
M.
Potential Treatment of
Congenital Short QT Syndrome: Response to Oral Quinidine.
Circulation 2004;110(17):
III-231
Presentation at AHA meeting
of the same data as in ref. # 12
16.
Filipecki A,
Trusz M, Lubinski A.
Prevalence of Very Short
QT Intervals in Patients with Idiopathic Ventricular Fibrillation and
Implanted ICD,
Circulation
2004;110(17);III-501
Oral presentation at AHA
meeting of patients with possible SQTS among young individuals, who had
undergone ICD implantation. No ECG’s were presented and the validity of
the data has later been questioned.
17.
Viskin S,
Zeltser D, Ish-Shalom M, Katz A, Glikson M, Justo D, Tekes-Manova D,
Belhassen B.
Is idiopathic
ventricular fibrillation a short QT syndrome? Comparison of QT intervals
of patients with idiopathic ventricular fibrillation and healthy
controls.
Heart Rhythm
2004;1(5):587-591
ECGs of 28 patients with idiopathic VF (17 men and 11 women, age 31 +/-
17 years) were compared to those of
270 age- and gender- matched healthy controls.
The QTc of males
with idiopathic VF was shorter than the QTc of healthy males (371 +/- 22
ms vs 385 +/- 19 ms, P = 0.034), and 35% of the male patients had QTc <
360 msec (range 326 – 350 msec) compared to only 10 % of male controls
(345-360 msec). No such differences were found among women.
The findings suggest that QTc
intervals shorter than 360 msec may entail some arrhythmic risk.
19. Zareba W.
Idiopathic VF and short
repolarization: Intriguing new concept.
Heart Rhythm
2004:1(5);592-593
Editorial comment to ref. #
18
20.
Antzelevitch
C, Francis J.
Congenital short QT
Syndrome.
Indian Pacing and
Electrophysiology Journal 2004;4(2):46-49.
Editorial with a brief description of the
genetic background and channelopathies which may lead to a short QT
interval.
21.
Extramiana F,
Antzelevitch C.
Amplified Transmural
Dispersion of Repolarization as the Basis for Arrhythmogenesis in a
Canine Ventricular-Wedge Model of Short-QT Syndrome.
Circulation
2004;110:3661-3666
The authors demonstrates
that shortening of the QT interval in a canine wedge preparation by
Pinacidil (a specific activator of the IK-ATP channel) is
associated with an increased trasmural dispersion of repolarization and
inducibility of VF by programmed stimulation.
2005
22. Bjerregaard P, Gussak
I.
Short QT Syndrome:
mechanisms, diagnosis and treatment.
Nat Clin Pract
Cardiovasc Med. 2005;2:84-87
The first review article
of Short QT Syndrome
23. Wolpert C, Schimpf R,
Giustetto C, Antzelevitch C, Cordeiro J, Dumaine R, Brugada R, Hong K,
Bauersfeld U, Gaita F, Borggrefe.
Further Insights into the
Effect of Quinidine in Short QT Syndrome Caused by a Mutation in HERG.
J Cardiovasc Electrophysiol
2005;16:54-58
Clinical observations in 3
patients with SQTS combined with in vitro patch clamp experiments on
transfected human embryonic kidney cells.
24. Hong K, Bjerregaard P,
Gussak I, Brugada R.
Short QT Syndrome and Atrial
Fibrillation Caused by Mutation in KCNH2.
J Cardiovasc Electrophysiol
2005;16:394-396
Presentation of genetic
testing of the first family with SQTS (see ref. # 3). The analysis
identified a missense mutation (C to G substitution at nucleotide 1764)
which resulted in the amino acid change (N588K) in KCNH2.
25. Schulze-Bahr E,
Breithardt G.
Short QT Interval and Short
QT Syndromes.
J Cardiovasc
Electrophysiol 2005;16:397-398
Editorial comment discussing
how to define a short QT interval.
26.
Schimpf R,
Bauersfeld U, Gaita F, Wolpert C.
Short QT syndrome:
Successful prevention of sudden cardiac death in an adolescent by
implantable cardioverter-defibrillator treatment for primary prophylaxis.
Heart Rhythm 2005;2:416-417
Case report of a previously
asymptomatic 16 y.o. male who received an ICD due to a family history of
SQTS and his own QT 248 msec and QTc 252 msec. Six month later the ICD
saved his life, when he developed ventricular fibrillation during sleep.
He is a member of the first German family described in ref. # 7.
This is the first
description of a patient with SQTS rescued by an ICD shock.
27. Priori SG, Pandit SV,
Rivolta I, Berenfeld O, Ronchetti E, Dhamoon A, Napolitano C, Anumonwo
J, Raffaele di Bartella M, Gudapakkam S, Bosi G, Stramba-Badiale M,
Jalife J.
A Novel Form of Short QT
Syndrome (SQT3) Is Caused by a Mutation in the KCNJ2 Gene.
Circ Res. 2005;96:800-807
An asymptomatic 5-year-old
girl presented an ECG during routine clinical evaluation with QTc of 315
ms and noticeably narrow and peaked T waves. Her father had a QTc of 320
ms and a history of presyncopal events and palpitations since the age of
15. Genetic analysis led to the identification in both affected
individuals of a single base pair substitution (G514A) in KCNJ2,
resulting in an amino acid change from aspartic acid to asparagine at
position 172 in the Kir2.1 potasseum channel.
27.
Schulze-Bahr
E.
Short QT Syndrome or
Anderson Syndrome. Yin and Yang of Kir2.1 Channel Dysfunction.
Circ Res. 2005;96:703-704
Editorial comment to # 27
28.
Giustetto C,
Wolpert C, Anttonen OM, Sbragia P, Leone G, Schimpf R, Borggrefe M,
Leclercq JF, Haissaguerre M, Gaita F.
Clinical Presentation of the
Patients with Short QT Syndrome.
Heart Rhythm 2005;2(5):S61
Abstract at the Heart Rhythm
Society meeting May, 2005
29.
Schimpf R, Giustetto C, Bjerregaard P, Gaita F, Gussak I,
Borggrefe M, Wolpert C.
Clinical
Follow-up of Patients with Short QT Syndrome.
Heart Rhythm 2005;2(5):S68
Abstract at the Heart Rhythm
Society meeting May, 2005
31. De Ferrari GM, Crotti
L, Lundquist AL, Pedrazzini M, Insolia R, Ferrandi C, Vicentini A,
Vaccari D, Schwartz PJ, George Jr. AL.
Long QT Syndrome With
Cardiac Arrest And Transient Short QT Due To A Novel KCNH2 Mutation
Causing Both Loss and Gain Of Function.
Heart Rhythm 2005;2(5):S145
Abstract at the Heart Rhythm
Society meeting May, 2005 showing evidence of both short and long QT
interval (mixed phenotype) in a patient with a KCNH2 mutation. (Awaiting
peer review publication)
32. Anttonen OM, Silvola J,
Kokkonen L, Brugada R, Junttila J, Hong K, Huikuri HV,
A Novel Inherited Syndrome
of Short QT Interval, Malignant Ventricular Arrhythmias and Familial
Clustering of Otosclerosis.
Heart Rhythm 2005;2(5):S172
Abstract at the Heart Rhythm
Society meeting May, 2007 describing a Finish family with both Short QT
Syndrome and Familial Otosclerosis. Result of genetic testing not
available.
33. Riera ARP, Ferreira C,
Dubner SJ, Schapachnik E, Soares JD, Francis J.
Brief Review of the
Recently Described Short QT Syndrome and Other Cardiac Channelopathies.
A.N.E. 2005;10(3):371-377
A review of cardiac
channelopathies including a description of a 27-year-old male with
paroxysmal atrial fibrillation, right bundle branch block and QT and QTc
intervals of 302 ms and 315 ms, respectively, at a heart rate of 67
beats/min.
34.
Wolpert C, Schimpf R, Veltman C, Giustetto C, Gaita F, Borggrefe
M.
Clinical characteristics and
treatment of short QT syndrome.
Expert Rev. Cardiovasc.
Ther. 2005;3(4):
Review article.
35.
Maury P,
Hollington L, Duparc A, Brugada R.
Short QT syndrome: Should we
push the frontier forward?
Heart Rhythm
2005;2:1135-1137
Description of a 15-year old
boy resuscitated from VF. QT intervals varied between 245 and 320 ms
with QTc’s at HR < 85 bpm between 315 and 375 ms. Repeat ECG’s in his
two brothers displayed QT intervals </= 300 ms in one sibling and of 320
ms in the other in whom ventricular arrhythmia was induced. QT intervals
of the mother were variable, but always at the lower limit value
(300-320 ms, QTc 365 ms), whereas the father had a normal ECG.
A plea was made not to limit
the definition of short QT syndrome only to patients with the very short
QT intervals in order to prevent under-diagnosis of some cases of this
syndrome.
36. Bjerregaard P, Gussak
I.
Short QT Syndrome.
A.N.E. 2005;10(4):436-440
Review article.
37. Borggrefe M, Wolpert C,
Antzelevitch C, Veltmann C, Giustetto C, Gaita F, Schimpf R.
Short QT syndrome.
Genotype-phenotype correlations.
J Electrocardiol
2005;38:75-80
Review article
38. Kirilmaz A, Ulusoy RE,
Kardesoglu E, Ozmen N, Demiralp E.
Short QT interval syndrome:
a case report.
J Electrocardiol
2005;38:371-374
The first patient with SQTS
in Turkey
39. Gussak I, Bjerregaard
P.
Short QT syndrome – 5 years
of progress.
J Electrocardiol
2005;38:375-377
Editorial describing the
progress in our knowledge of SQTS five years after the discovery of the
syndrome.
40.
Hong K, Piper DR, Diaz-Valdecantos A, Brugada J, Oliva A,
Burashnikov E, Santos-de-Soto J, Grueso-Montero J, Diaz-Enfante E,
Brugada P, Sachse F, Sanguinetti MC, Brugada R,
De
novo KCNQ1 mutation responsible for atrial fibrillation and Short
QT Syndrome in utero.
Cardiovasc Res
2005;68:433-440
The first description of a
newborn with atrial fibrillation in the setting of SQTS diagnosed in
utero and linked to a De Novo KCNQ1 mutation.
41.
Bjerregaard P,
Jahangir A, Gussak I.
Targeted therapy for short
QT syndrome.
Expert Opin. Ther. Targets
2006;10(3):393-400
Review comparing LQTS with
SQTS. Also potential targets for therapy in SQTS patients is reviewed
for KCNH2, KCNQ1 and KCNJ2 mutation patients separately.
42.
Cordeiro JM,
Brugada R, Wu YS, Hong K, Dumaine R.
Modulation of IKr
inactivation by mutation N588K in KCNH2: A link to arrhythmogenesis in
short QT syndrome.
Cardiovascular Research
2005;67:498-509
The authors measured the
characteristics of HERG current generated by wild-type KCNH2 and the
N588K mutant channel expressed in mammalian TSA201 cells. They found
that the ventricular action potentials were preferentially reduced in
SQTS, while the Purkinje fiber action potentials remained unchanged.
This would lead to a shortening of the refractory period in the
ventricles, but not in the Purkinje fibers. They suggested that the
longer action potentials in the Purkinje fibers might re-excite the
repolarized endocardial layer of the ventricles and thereby create
tachyarrhythmias. This may also explain the wider than usual separation
between T and U waves seen in SQTS patients.
43. McPate MJ, Duncan RS,
Milnes JT, Witchel HJ, Hancox JC.
The N588K-HERG K+
channel mutation in the ‘short QT syndrome’: Mechanism of
gain-in-function determined at 37 oC.
Biochemical and Biophysical
Research Communications 2005;334:441-449
These authors examined at
physiologic temperature the importance of the S5-P linker for HERG
channel function. They demonstrated that N588K-HERG contributes
increased repolarising current earlier in the ventricles action
potential due to a ~+60 mV shift in voltage dependence of IHERG
inactivation. This explains the accelerated repolarisation and short QT
interval in some SQTS patients.
43.
Antzelevitch
C.
Cardiac repolarization. The
long and short of it.
Europace 2005;7:53-59
Review of the importance of
electrical heterogeneity of transmural ventricular repolarization in the
heart for the occurrence of tachy-arrhythmias in LQTS, SQTS, Brugada
syndrome and catecholaminergic polymorph ventricular tachycardia.
44.
Brugada R,
Hong K, Cordeiro JM, Dumaine R.
Short QT Syndrome.
CMAJ 2005;173(11):1349-1354
Canadian review article of
SQTS
45.
Paulussen AD,
Raes A, Jongbloed RJ, Gilissen RA, Wilde AA, Snyders DJ, Smeets HJ,
Aerssens J.
HERG mutation predicts short
QT based on channel kinetics but causes long QT by heterotetrameric
trafficking deficiency.
Cardiovasc Res
2005;67(3):467-475
46.
Weiss DL,
Seemann G, Sachse FB, Doessel O.
Modelling of short QT
syndrome in a heterogeneous model of the human ventricular wall.
Europace
2005;7:S105-S117
These authors have been able
to create a computer model of human cardiomyocytes that incorporates
modifications in IKr as seen in some SQTS patients.
They found a heterogeneous abbreviation of the action potential duration
leading to a decreased dispersion of repolarization in heterogeneous
tissue. Repolarisation was homogenized and the final repolarisation was
shifted to epicardial sites.
2006
47.
Tanabe Y,
Hatada K, Naito N, Aizawa Y, Chinushi M, Nawa H, Aizawa Y.
Over-expression of Kv1.5 in
rat cardiomyocytes extremely shortens the duration of the action
potential and causes rapid excitation.
Biochemical and Biophysical
Research Communications 2006;345:1116-1121
Tanabe at als. Have been
able to create a model based upon fetal rat cardiomyocytes with
over-expression of Kv1.5 leading to shortening of the action potential.
They have suggested that this model can be used to study the
arrhythmogenic substrate in SQTS.
49. Cerrone M, Noujaim S,
Jalife J.
The short QT syndrome as a
paradigm to understand the role of potassium channels in ventricular
fibrillation.
J Int Med 2006;259:24-38
Review article.
Molecular and genetic features of SQTS is addressed.
New knowledge on
the mechanism of wavebreak, which is the hallmark of
reentry initiation, is summarized.
The authors stat, that it is likely that the mechanisms that lead
to electrical instability and eventually results in VF in patients
carrying mutations in HERG or KvLQT1 would be different from those
resulting from gain-of-function substitutions in Kir2.1 .
50. Itoh H, Horie M, Ito M,
Imoto K.
Arrhythmogenesis in the
short QT syndrome associated with combined HERG channel gating defects:
a simulation study.
Circ J
2006;70(4):502-508
Conclusion: Although gain of function of
the KCNH2 (HERG) channel shortens APD in the Short QT Syndrome,
arrhythmogenesis may be associated not only with gain of function, but
also with accelerated deactivation of KCNH2.
51.
Schulze-Bahr
E.
Short QT Syndromes.
Herz
2006;31(2):118-122
Review article in German
52.
Gallagher MM, Magliano G, Yap YG, Padula M, Morgia V, Postorino
C, Liberato FD, Leo R, Borzi M, Romeo F.
Distribution and Prognostic
Significance of QT Intervals in the Lowest Half Centile in 12,012
Apparently Healthy Persons.
Am J Cardiol 2006;98:933-935
Among 12,012 healthy subjects (90.7 % male)
30 +/- 10 years old there were 60 with a QTc < 361 msec and the shortest
QTc was 335 msec. 36 of these 60 subjects were followed for 7.9 +/- 4.5
years and none of them died suddenly.
A QTc </= 360 msec was seen in only 0.4 %
The absence of any QTc < 335
msec confirms the impression that Short QT Syndrome is a distinct
clinical entity involving QT intervals substantially shorter than those
found in a normal population.
53.
Giustetto
C, DiMonte F, Wolpert C, Borggrefe M, Schimpf R, Sbragia P, Leone G,
Maury P, Anttonen O, Haissaguerre M, Gaita F.
Short QT syndrome: clinical
findings and diagnostic-therapeutic implications.
European Heart Journal
2006;27:2449-2447
54.
McPate MJ,
Duncan RS, Witchel HJ, Hancox JC.
Disopyramide is an
effective inhibitor of mutant HERG K+ channels involved in
variant 1 short QT syndrome.
J of Molecular and Cellular
Cardiology 2006-
Using whole-cell patch clamp recordings
from Chinese Hamster Ovary cells expressing HERG with a N588K mutation
(like SQT1) it was demonstrated, that the HERG-blocking potency of
disopyramide was reduced only 1.5 fold. Since other studies have shown
that Quinidine’s blocking effect of N588K-HERG channels was reduced 5.8
fold and Sotalol’s 20 fold, the study provides a rational basis for its
evaluation as a treatment for STQ1.
55. Lu LX, Zhou W, Zhang
X, Cao Q, Yu K, Zhu C.
Short QT Syndrome: A case
report and review of literature.
Resuscitation
2006;71:115-121
The first description from
China of a family with SQTS. Includes some very interesting ECG
rhythm-strips from Holter monitoring showing self-terminating polymorph
ventricular tachycardia initiated by a very premature PVC.
Amiodarone combined with a
beta-blocker was effective in treating the episodes of polymorph
ventricular tachycardia.
56.
Rhodes
TE, Crotti L, Arnestad M, Insolia R, Pedrazzini M, Ferrandi C, Rognum T,
Schwartz PJ, George AL.
Gain of Function KCNQ1 Mutation Associated
With Sudden Infant Death Syndrome
Heart Rhythm 2006;3(5):S2
During the examination of 201 Norwegian
SIDS cases for genetic variants in the major LQTS genes, a
gain-of-function KCNQ1 mutation was found. This mutation is predicted to
enhance cardiac repolarization resulting in a shortened QT interval and
an increased risk of atrial and ventricular tachyarrhythmias - features
typical of the Short QT Syndrome.
57.
Assadi
R, Chang R, Abdipour A, Pai SM, Jutzy KR.
Possible
Increased Risk of Cardiac Arrhythmias in Patients With Acquired Short QT
Interval
JACC 2007;xxx:8A
Nineteen patients with QTc < 300 msec were
compared with 36 patients matched by sex, age and ethnicity and
evaluated for cardiac arrhythmias on the day of the short
QT.
Twelve cases (63%) showed afib/flutter and
32 % developed cardiac arrest due to VF after short QT was detected.
Corrected for known causes of a short QT
interval, patients with a short QT had an increased risk of arrhythmias
compared to the controls (p=0.017).
Conclusion: Short QT including the acquired
form may be an independent risk factor for cardiac tachy-arrhythmias.
2007
58.
Reinig
MG, Engel TR
The Shortage
of Short QT Intervals
CHEST
2007;132:246-249
In a hospital based population of 106,432
patients, not a single one was found to have a QTc </= 300msec
59.
Antzelevitch C, Pollevick GD, Cordeiro JM, Casis O, Sanguinetti MC,
Aizawa Y, Guerchicoff A, Pfeiffer R, Oliva A, Wollnik B, Gelber P,
Bonaros EP, Burashnikov E, Wu Y, Sargent JD, Schickel S, Oberheiden R,
Bhatia A, Hsu L-F, Jaissaguerre M, Schrimpf R, Borggrefe M, Wolpert C.
Loss-of-Function Mutations in the Cardiac Calcium Channel Underlie a New
Clinical Entity Characterized by ST-Segment Elevation, Short OT
Intervals, and Sudden Cardiac Death
Circulation 2007;115:442-449
Among 82 probands with a clinically robust
diagnosis of Brugada syndrome, 6 % (5) presented with a
shorter-than-normal QT interval.
Three of these 5 probands with a QTc </=
360 msec carried a cardiac L-type calcium channel missense mutation (CACNAIC
or CACNBSb). A loss of function of any of these channels can contribute
to a sudden death syndrome that consists of a shorter-than-normal QT
interval and ST-segment elevation (Brugada Syndrome phenotype).
This is the first report of
loss-of-function mutations in genes encoding the cardiac L-type calcium
channel to be associated with a familial sudden cardiac death syndrome
in which a Brugada Syndrome phenotype is combined with
shorter-than-normal QT intervals.
60.
Milberg
P, Tegelkamp R Osada N, Schimpf R, Wolpert C, Breithardt G, Borggrefe M,
Eckardt L.
Reduction of
Dispersion of Repolarization and Prolongation of Postrepolarization
Refractoriness Explain the Antiarrhthmic Effects of Quinidine in a Model
of Short QT Syndrome
J Cardiovasc
Electrophysiol 2007;18:658-664
A model of Short
QT Syndrome was created in 48 Langendorff perfused rabbit hearts by
administering an IK-ATP channel opener (Pinacidil) in
increasing concentrations.
By MAP recording
and programmed electrical stimulation technique the effect of Sotalol,
Flecainide and Quinidine on dispersion of repolarization, MAP duration,
refractoriness, postrepolarization refractoriness and inducibility of VF
was assessed.
Only Quinidine
reduced the inducibility of VF and it was associated with significantly
greater prolongation of MAP duration, refractoriness and
postrepolarization refractoriness compared with Sotalol and Flecainide.
Quinidine was also the only one of the 3 drus which reduced dispertion
of refractoriness.
The biggest
limitation of the study is the fact that the ATP sensitive channel used
in this study has not been connected with SQTS in humans.
61.
Kaufman
E.
Quinidine in
Short QT Syndrome: An Old Drug for a New Disease
J Cardiovasc
Electrophysiol 2007;18:665-666
Editorial comment
to previous article.
62.
Anttonen O, Junttila MJ, Rissanen H, Reunanen A, Viitasalo M,
Huikuri HV.
Prevalence and Prognostic Significance
of Short QT Interval an a Middle-Aged Finnish Population
Circulation 2007;116:714-720
QT intervals were measured from the 12-lead
ECGs of 10,822 subjects (5,658 males, mean age 44 +/- 8.4 years)
enrolled in a population study and followed for 29 +/- 10 years.
QTc < 360 msec was seen in 2.8 %
QTc < 340 msec was seen in 0.4 %.
QTc < 320 msec was seen in 0.1 %.
During follow up there were no sudden
deaths in the subjects with a QTc < 340 msec.
The higher number of subjects with a
short QT interval in this study than in the study by Gallagher et al. (#
52) is likely due to the difference in defining the end of the T wave.
In the present study the end of the T wave was defined as a point at
which a tangent of the descending limb of the T wave intersects the
baseline, whereas Gallagher et al defined it as the point at which the T
wave returned to the isolelectric line.
Another point of significance is the
limitations in the use of Bazett’s correction formula. In both the study
by Gallagher et al. and the present study, subjects with the shortest QT
were the subjects with the lowest heart rate. Bazett’s formula is known
for its tendency to over-correct the QT interval during bradycardia.
63.
Viswanathan MN, Page RL.
Short QT. What
Does It Matter?
Circulation
2007;116:686-688
Editorial to the
previous article (#62)
last updated:
09/30/2007 |