Abstract 302: Prevalence of Acquired Long QT Syndrome in Patients with Aortic Valve Stenosis

2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Amanulla Khaji ◽  
Hafiz M Waqas Khan ◽  
Zakir Shaik ◽  
Ahmed Fityani ◽  
Eric Gnall ◽  
...  
Keyword(s):  
Heart Failure ◽  
Aortic Valve ◽  
Aortic Valve Stenosis ◽  
Long Qt Syndrome ◽  
Qt Prolongation ◽  
Long Qt ◽  
Acquired Long Qt Syndrome ◽  
Increased Risk ◽  
Qt Syndrome ◽  
Artery Disease

Introduction: QT prolongation is associated with an increased risk of sudden cardiac death (SCD). Patients (pts) with aortic valve stenosis (AVS), in particular, have a higher incidence of SCD. We hypothesized that cardiac remodeling in the structural heart abnormalities may result in secondary QT prolongation in AVS. Methods: Electronic medical records in AVS pts prior to valve repairs/replacement in a single center from 2005-2015 were retrieved. ECGs showing QRS duration (QRSD) > 120 ms or non-sinus rhythm were excluded for QT evaluations. Information regarding concomitant hypertension (HTN), dyslipidemia, diabetes, coronary artery disease, heart failure and presence of QT-prolonging factors (electrolytes imbalance and using QT prolonging drugs) was also evaluated. Results: Among 419 AVS pts [median age 75 (13) yrs, male 56%] with normal QRSD [94 (16) ms], the prevalence of acquired long QT syndrome with and without known QT-prolonging factors is shown in Table 1. More pts with heart failure had QTc ≥ 450 ms than those without HF (64% vs. 48%, p <0.01). Conclusions: Regardless of the known QT prolonging factors, the prevalence of QT prolongation is high in AVS and may serve as a pathogenetic factor for sudden death in patients with aortic valve stenosis.

Atrioventricular block in a new born with acquired long QT syndrome

2001 ◽  
Vol 11 (6) ◽  
pp. 680-682 ◽  
Author(s):  
John R. Phillips ◽  
Christopher L. Case ◽  
Paul C. Gillette
Keyword(s):  
Intensive Care Unit ◽  
Atrioventricular Block ◽  
Long Qt Syndrome ◽  
Qt Interval ◽  
Neonatal Intensive Care ◽  
Qt Prolongation ◽  
Long Qt ◽  
Acquired Long Qt Syndrome ◽  
Qt Syndrome ◽  
Congenital Long Qt Syndrome

We report a case of 2:1 atrioventricular block associated with acquired long QT syndrome. A newborn presented to our neonatal intensive care unit with intermittent bradycardia due to 2:1 atrioventricular block. Initial evaluation showed QT prolongation and significant electrolytic abnormalities. After correction of the electrolytic imbalance, the QT interval normalized and atrioventricular block resolved. Compared to congenital long QT syndrome with 2:1 atrioventricular block, acquired long QT syndrome with comparable atrioventricular block has a benign prognosis, provided treatment is initiated quickly.

A SCN5A mutation caused ST elevation, transient QT prolongation and sudden death: An atypical phenotype of Brugada-long QT syndrome?

Heart Rhythm ◽  
2005 ◽  
Vol 2 (5) ◽  
pp. S265
Author(s):  
Li Zhang ◽  
Tiehua Chen ◽  
Michael Sheets ◽  
Robert L. Lux ◽  
Michael S. Schaffer ◽  
...  
Keyword(s):  
Sudden Death ◽  
Long Qt Syndrome ◽  
Qt Prolongation ◽  
Long Qt ◽  
St Elevation ◽  
Qt Syndrome ◽  
Atypical Phenotype ◽  
Scn5a Mutation

Endocrinopathies mimicking gene negative long QT syndrome

2021 ◽  
pp. 1-3
Author(s):  
Praloy Chakraborty ◽  
Jason D. Roberts ◽  
Michael H. Gollob
Keyword(s):  
Genetic Testing ◽  
Long Qt Syndrome ◽  
Qt Prolongation ◽  
Long Qt ◽  
Ventricular Repolarisation ◽  
Qt Syndrome ◽  
Hormonal Milieu

Abstract Ventricular repolarisation can be influenced by hormonal milieu which may mimic long QT syndrome. We describe a series of patients referred for genetic testing for diagnosed long QT syndrome where a detailed clinical workup demonstrated endocrinopathies as the cause of presumed “gene negative” long QT syndrome and QT prolongation.

Abstract 15209: LPA Variants Are Associated With Aortic Valve Stenosis, Heart Failure and Chronic Kidney Disease

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Ozan Dikilitas ◽  
Benjamin A Satterfield ◽  
Maya Safarova ◽  
Shoa L Clarke ◽  
Catherine Tcheandjieu ◽  
...  
Keyword(s):  
Heart Failure ◽  
Chronic Kidney Disease ◽  
Kidney Disease ◽  
Aortic Valve ◽  
Aortic Valve Stenosis ◽  
European Ancestry ◽  
Atherosclerotic Cardiovascular Disease ◽  
Disease Phenotypes ◽  
Emerge Network ◽  
Artery Disease

Background: The pathophysiology of lipoprotein (a) [Lp(a)] remains obscure. We conducted a phenome wide analysis study (PheWAS) to identify pleiotropic effects of LPA variants. Methods: Among 51,843 European-ancestry participants (age 58±16 years, 54% female) of the electronic MEdical Records and Genomics (eMERGE) network we assessed whether LPA variants exhibited pleiotropic affects through an electronic health record-based PheWAS. We adjusted significant associations by presence of atherosclerotic cardiovascular disease (ASCVD; defined as a composite of coronary heart disease, cerebrovascular disease, and peripheral artery disease) to determine whether those associations were independent of ASCVD. Results: In PheWAS analysis, we tested 864 phecodes with 36 independent LPA variants. We identified 21 significant associations with non-ASCVD phenotypes including heart failure, aortic valve stenosis, and chronic kidney disease of which 14 were replicated across independent cohorts. The strength of associations between the LPA variant rs10455872 and both heart failure and aortic valve stenosis related phecodes were significantly attenuated after adjustment for ASCVD. However, the association with chronic kidney disease phecode remained independent following adjustment for ASCVD without any attenuation in the estimated odds ratio (Table). Conclusions: LPA genetic variants were associated with aortic valve stenosis, heart failure and chronic kidney disease. The observed association of LPA variant rs10455872 with aortic stenosis and heart failure appear to be partially mediated by ASCVD, while the association with chronic kidney disease appears to be independent of ASCVD. Additional studies are needed to elucidate potential mechanisms by which Lp(a) may contribute to the pathogenesis of non-ASCVD disease phenotypes.

Abstract 5316: hERG 1b as a Potential Target for Inherited and Acquired Long QT Syndrome

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Gail A Robertson ◽  
Harinath Sale ◽  
David Tester ◽  
Thomas J O’Hara ◽  
Pallavi Phartiyal ◽  
...  
Keyword(s):  
Action Potential ◽  
Long Qt Syndrome ◽  
Time Course ◽  
Drug Sensitivity ◽  
Long Qt ◽  
Hek 293 ◽  
Hek 293 Cells ◽  
Acquired Long Qt Syndrome ◽  
293 Cells ◽  
Qt Syndrome

Cardiac I Kr is a critical repolarizing current in the heart and a target for inherited and acquired long QT syndrome. Biochemical studies show that native I Kr channels are heteromers composed of both hERG 1a and 1b subunits, yet our current understanding of I Kr functional properties derives primarily from studies of homo-oligomers of the original hERG 1a isolate. The hERG 1a and 1b subunits are identical except at the amino (NH2) terminus, which in hERG 1b is much shorter and has a unique primary sequence. We compared the biophysical properties of currents produced by hERG 1a and 1a/1b channels expressed in HEK-293 cells at near-physiological temperatures. We found that heteromeric hERG 1a/1b currents are much larger than hERG 1a currents and conduct 80% more charge during an action potential. This surprising difference corresponds to a two-fold increase in the apparent rates of activation and recovery from inactivation, which reduces rectification and facilitates current rebound during repolarization. Kinetic modeling shows these gating differences account quantitatively for the differences in current amplitude between the two channel types. Depending on the action potential model used, loss of 1b predicts an increase in action potential duration of 27 ms (7%) or 41 ms (17%), respectively. Drug sensitivity was also different. Compared to homomeric 1a channels, heteromeric 1a/1b channels were inhibited by E-4031 with a slower time course and a corresponding four-fold positive shift in the IC 50 . Differences in current kinetics and drug sensitivity were modeled by “NH2 mode” gating with conformational states bound by the amino terminus in hERG 1a homomers but not 1a/1b heteromers. The importance of hERG 1b in vivo is supported by the identification of a 1b-specific A8V missense mutation in 1/269 unrelated genotype-negative LQTS patients and absent in 400 control alleles. Mutant 1bA8V expressed alone or with hERG 1a in HEK-293 cells nearly eliminated 1b protein. Thus, mutations specifically disrupting hERG 1b function are expected to reduce cardiac I Kr , prolong QT interval and enhance drug sensitivity, thus representing a potential mechanism underlying inherited or acquired LQTS.

Pro- and antiarrhythmic effects of fast cardiac pacing in a canine model of acquired long QT syndrome

2004 ◽  
Vol 369 (4) ◽  
pp. 447-454 ◽  
Author(s):  
Alexander Bauer ◽  
J. Kevin Donahue ◽  
Frederik Voss ◽  
Ruediger Becker ◽  
Patricia Kraft ◽  
...  
Keyword(s):  
Long Qt Syndrome ◽  
Cardiac Pacing ◽  
Canine Model ◽  
Long Qt ◽  
Acquired Long Qt Syndrome ◽  
Qt Syndrome ◽  
Antiarrhythmic Effects

scholarly journals Prolonged QTc: "Mind the Gap"

2014 ◽  
Vol 2 (1) ◽  
pp. 44-45
Author(s):  
Ahmad Mursel Anam ◽  
Raihan Rabbani ◽  
Farzana Shumy ◽  
M Mufizul Islam Polash ◽  
M Motiul Islam ◽  
...  
Keyword(s):  
Cardiac Arrest ◽  
Long Qt Syndrome ◽  
Qt Interval ◽  
Torsades De Pointes ◽  
Junior Doctors ◽  
Long Qt ◽  
Acquired Long Qt Syndrome ◽  
Prolonged Qt Interval ◽  
Prolonged Qt ◽  
Qt Syndrome

We report a case of drug induced torsades de pointes, following acquired long QT syndrome. The patient got admitted for shock with acute abdomen. The initial prolonged QT-interval was missed, and a torsadogenic drug was introduced post-operatively. Patient developed torsades de pointes followed by cardiac arrest. She was managed well and discharged without complications. The clinical manifestations of long QT syndromes, syncope or cardiac arrest, result from torsades de pointes. As syncope or cardiac arrest have more common differential diagnoses, even the symptomatic long QT syndrome are commonly missed or misdiagnosed. In acquired long QT syndrome with no prior suggestive feature, it is not impossible to miss the prolonged QT-interval on the ECG tracing. We share our experience so that the clinicians, especially the junior doctors, will be more alert on checking the QT-interval even in asymptomatic patients. DOI: http://dx.doi.org/10.3329/bccj.v2i1.19970 Bangladesh Crit Care J March 2014; 2 (1): 44-45

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