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European Journal of Preventive... Mar 2023
Topics: Humans; Long QT Syndrome; Electrocardiography
PubMed: 35917281
DOI: 10.1093/eurjpc/zwac162 -
Journal of Cardiovascular... Jan 2023
Topics: Humans; Torsades de Pointes; Electrocardiography; Long QT Syndrome
PubMed: 36335630
DOI: 10.1111/jce.15736 -
The New England Journal of Medicine May 2008
Topics: Arrhythmias, Cardiac; Child; Humans; Life Style; Long QT Syndrome
PubMed: 18450612
DOI: 10.1056/NEJMc080195 -
Cardiology in the Young Jun 2022Ventricular repolarisation can be influenced by hormonal milieu which may mimic long QT syndrome. We describe a series of patients referred for genetic testing for...
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.
Topics: Electrocardiography; Genetic Testing; Humans; Long QT Syndrome
PubMed: 34814967
DOI: 10.1017/S1047951121004388 -
The Journal of Physiology Sep 2013Congenital long QT syndrome (LQTS) is caused by single autosomal-dominant mutations in a gene encoding for a cardiac ion channel or an accessory ion channel subunit.... (Review)
Review
Congenital long QT syndrome (LQTS) is caused by single autosomal-dominant mutations in a gene encoding for a cardiac ion channel or an accessory ion channel subunit. These single mutations can cause life-threatening arrhythmias and sudden death in heterozygous mutation carriers. This recognition has been the basis for world-wide staggering numbers of subjects and families counselled for LQTS and treated based on finding (putative) disease-causing mutations. However, prophylactic treatment of patients is greatly hampered by the growing awareness that simple carriership of a mutation often fails to predict clinical outcome: many carriers never develop clinically relevant disease while others are severely affected at a young age. It is still largely elusive what determines this large variability in disease severity, where even within one pedigree, an identical mutation can cause life-threatening arrhythmias in some carriers while in other carriers no disease becomes clinically manifested. This suggests that additional factors modify the clinical manifestations of a particular disease-causing mutation. In this article, potential demographic, environmental and genetic factors are reviewed, which, in conjunction with a mutation, may modify the phenotype in LQTS, and thereby determine, at least partially, the large variability in disease severity.
Topics: Action Potentials; Animals; Gene-Environment Interaction; Genotype; Humans; Long QT Syndrome
PubMed: 23753525
DOI: 10.1113/jphysiol.2013.254920 -
Cleveland Clinic Journal of Medicine Aug 2008Congenital long QT syndrome is an inherited disorder of cardiac repolarization that predisposes to syncope and to sudden death from polymorphic ventricular tachycardia.... (Review)
Review
Congenital long QT syndrome is an inherited disorder of cardiac repolarization that predisposes to syncope and to sudden death from polymorphic ventricular tachycardia. The disorder should be suspected when the electrocardiogram shows characteristic QT abnormalities, or when there is a family history of long QT syndrome or of an event that raises suspicion of long QT syndrome, such as sudden death, syncope, or ill-defined "seizure" disorder. We can now classify some types of congenital long QT syndrome according to their genetic mutations and their triggers, such as exercise, rest, or startle.
Topics: Adrenergic beta-Antagonists; Decision Support Systems, Clinical; Defibrillators, Implantable; Electrophysiology; Female; Genetic Testing; Genotype; Humans; Long QT Syndrome; Mutation; Physicians, Family; Pregnancy; Pregnancy Complications, Cardiovascular; Primary Health Care; Risk Assessment; Time Factors
PubMed: 18756841
DOI: 10.3949/ccjm.75.8.591 -
The New England Journal of Medicine Jan 2008
Review
Topics: Adolescent; Adrenergic beta-Antagonists; Child; Death, Sudden, Cardiac; Defibrillators, Implantable; Diagnosis, Differential; Electrocardiography; Female; Genetic Carrier Screening; Genetic Testing; Heterozygote; Humans; Long QT Syndrome; Mutation; Pedigree; Practice Guidelines as Topic; Syncope
PubMed: 18184962
DOI: 10.1056/NEJMcp0706513 -
Zeitschrift Fur Kardiologie Sep 2004There is increased awareness of the extent to which cardiac function is influenced by gender. One of the most dramatic and potentially lethal differences is that seen in... (Review)
Review
There is increased awareness of the extent to which cardiac function is influenced by gender. One of the most dramatic and potentially lethal differences is that seen in cardiac repolarization reflected in the QT interval of the surface ECG. Gender differences in QT and QTc intervals have been observed to change during the lifetime in the general population. These differences can be explained to a large extent by sex hormone driven differences in gene expression of myocardial ion channels. Numerous studies have shown that women's risk to suffer arrhythmias in the context of QT prolonging drugs is doubled compared to men. For familial long QT syndrome there is no conclusive evidence for gender effects with respect to disease onset or mortality. Only subgroup analysis by genotype demonstrated a higher risk in female patients carrying mutations in the LQT2 locus. Special attention should be given to drug-induced QT prolongation in women.
Topics: Adolescent; Adult; Age Factors; Electrocardiography; Female; Gene Expression; Genotype; Gonadal Steroid Hormones; Humans; Incidence; Ion Channels; Long QT Syndrome; Middle Aged; Mutation; Orchiectomy; Risk Assessment; Risk Factors; Sex Factors; Time Factors; Virilism
PubMed: 15365730
DOI: 10.1007/s00392-004-0129-6 -
Circulation Research Sep 2021
Topics: Cyclic Nucleotide Phosphodiesterases, Type 5; Humans; Long QT Syndrome
PubMed: 34473532
DOI: 10.1161/CIRCRESAHA.121.319851 -
Circulation. Arrhythmia and... Feb 2024Genetic testing has become standard of care for patients with long QT syndrome (LQTS), providing diagnostic, prognostic, and therapeutic information for both probands... (Review)
Review
Genetic testing has become standard of care for patients with long QT syndrome (LQTS), providing diagnostic, prognostic, and therapeutic information for both probands and their family members. However, up to a quarter of patients with LQTS do not have identifiable Mendelian pathogenic variants in the currently known LQTS-associated genes. This absence of genetic confirmation, intriguingly, does not lessen the severity of LQTS, with the prognosis in these gene-elusive patients with unequivocal LQTS mirroring genotype-positive patients in the limited data available. Such a conundrum instigates an exploration into the causes of corrected QT interval (QTc) prolongation in these cases, unveiling a broad spectrum of potential scenarios and mechanisms. These include multiple environmental influences on QTc prolongation, exercise-induced repolarization abnormalities, and the profound implications of the constantly evolving nature of genetic testing and variant interpretation. In addition, the rapid advances in genetics have the potential to uncover new causal genes, and polygenic risk factors may aid in the diagnosis of high-risk patients. Navigating this multifaceted landscape requires a systematic approach and expert knowledge, integrating the dynamic nature of genetics and patient-specific influences for accurate diagnosis, management, and counseling of patients. The role of a subspecialized expert cardiogenetic clinic is paramount in evaluation to navigate this complexity. Amid these intricate aspects, this review outlines potential causes of gene-elusive LQTS. It also provides an outline for the evaluation of patients with negative and inconclusive genetic test results and underscores the need for ongoing adaptation and reassessment in our understanding of LQTS, as the complexities of gene-elusive LQTS are increasingly deciphered.
Topics: Humans; Electrocardiography; Long QT Syndrome; Genotype; Risk Factors; Genetic Testing
PubMed: 38264885
DOI: 10.1161/CIRCEP.123.012356