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Current Opinion in Cardiology May 2010As genetic testing for long QT syndrome (LQTS) has become readily available, important advances are being made in understanding the exact link between ion channel... (Review)
Review
PURPOSE OF REVIEW
As genetic testing for long QT syndrome (LQTS) has become readily available, important advances are being made in understanding the exact link between ion channel mutation and observed phenotype. This paper reviews recent findings in the literature.
RECENT FINDINGS
Congenital LQTS is an important cause of sudden cardiac death. To date, 12 genes have been identified as the cause of congenital LQTS. With increasing availability of genetic testing, subtype-specific management of LQTS has become the standard of care. Detailed correlative studies between LQTS mutations and clinical phenotypes are leading the field towards 'mutation-specific' management within LQTS subtypes. A clear link between the distinct functional/biophysical defect in each LQT mutation and disease phenotype is complicated by the variable penetrance and pleiotropic expression of clinical phenotype. This is especially evident with the overlap syndrome now documented for several sodium channel (SCN5A) mutations.
SUMMARY
The management of LQTS has become subtype-specific due to the availability of genotype information. Review of recent literature suggests that 'mutation-specific' management is possible based upon distinct functional/biophysical characteristics of mutations within each LQT gene. Further research is required to clearly delineate the molecular and cellular mechanisms underlying variable penetrance, and pleiotropic expression of LQTS mutations.
Topics: Death, Sudden, Cardiac; Genetic Testing; Humans; Ion Channels; Long QT Syndrome; Mutation
PubMed: 20224391
DOI: 10.1097/HCO.0b013e32833846b3 -
The New England Journal of Medicine May 2008
Topics: Adrenergic beta-Antagonists; Ganglionectomy; Humans; Long QT Syndrome
PubMed: 18456919
DOI: No ID Found -
Europace : European Pacing,... Feb 2023
Topics: Humans; Arrhythmias, Cardiac; Long QT Syndrome; Catheter Ablation; Death, Sudden
PubMed: 36610793
DOI: 10.1093/europace/euac266 -
Current Opinion in Pediatrics Dec 2014The sudden death of a previously healthy young individual is a dreadful occurrence. Identifying those at risk of such a dire outcome, and appropriately managing and... (Review)
Review
PURPOSE OF REVIEW
The sudden death of a previously healthy young individual is a dreadful occurrence. Identifying those at risk of such a dire outcome, and appropriately managing and counseling them, has been an ongoing challenge, but rapid advances are being made. This review will focus on the long QT syndrome (LQTS), the most common of the potentially lethal inheritable arrhythmias, with specific focus on the genetics relevant to clinical presentation, therapy and response.
RECENT FINDINGS
The past 2 decades have seen tremendous progress in the field of inheritable arrhythmias. Emphasis is given to risk stratification, screening of family members, and the counseling of young athletes, as well as new developments in screening and treatment.
SUMMARY
For the primary care provider, long QT syndrome should be considered during the evaluation of syncope, near-syncope and seizures, especially in the setting of exercise or with a family history of sudden unexplained death in a first-degree relative. The corrected QT interval (QTc) should be assessed as a routine when obtaining electrocardiograms. If there are concerns on the basis of electrocardiogram findings, medical history or family history, referral to a cardiologist is indicated. Providers need to be cognizant of the challenges of therapy and lifestyle changes for patients and families with long QT syndrome.
Topics: Child; Death, Sudden, Cardiac; Electrocardiography; Humans; Long QT Syndrome; Seizures; Syncope
PubMed: 25313972
DOI: 10.1097/MOP.0000000000000161 -
Current Opinion in Pediatrics Oct 2006Dramatic advances have been made in understanding of both the genetics and the phenotypic expression of congenital long QT syndrome. This paper reviews recent clinically... (Review)
Review
PURPOSE OF REVIEW
Dramatic advances have been made in understanding of both the genetics and the phenotypic expression of congenital long QT syndrome. This paper reviews recent clinically relevant literature.
RECENT FINDINGS
Long QT syndrome is one of the leading causes of sudden cardiac death. This syndrome, once diagnosed by a clinical profile, has been more clearly defined by specific gene defects causing ion channel abnormalities in the beating heart. Genetic testing for long QT syndrome, once available only through research laboratories, is now commercially available. Diagnosis, risk assessment, and management are increasingly being guided by gene-specific diagnoses. In a family with suspected disease, the genetic test will determine the defect in as many as 75% of subjects. Once the diagnosis is made, the mainstay of therapy continues to be beta-blockers. Implantable cardioverter-defibrillators are indicated in patients at high risk for malignant arrhythmias.
SUMMARY
Long QT syndrome is one of the first cardiovascular diseases to see the dramatic changes that bench research can bring to the clinical arena. Future research is needed to determine the gene defect in the remaining 25% of patients with suspected long QT syndrome and in risk stratification.
Topics: Child; Genotype; Humans; Long QT Syndrome; Risk Assessment
PubMed: 16969163
DOI: 10.1097/01.mop.0000245349.30089.bf -
European Heart Journal Feb 2009
Topics: Humans; Long QT Syndrome; Myocardial Contraction; Ultrasonography; Ventricular Dysfunction, Left
PubMed: 19151080
DOI: 10.1093/eurheartj/ehn587 -
Journal of the American College of... May 2020
Topics: Channelopathies; Humans; Immunotherapy; KCNQ1 Potassium Channel; Long QT Syndrome; Peptides
PubMed: 32354383
DOI: 10.1016/j.jacc.2020.03.027 -
Revue Medicale Suisse Aug 2013The long QT syndrome may be acquired or genetically determined. The syndrome is characterized by a prolonged QT interval and is associated with an increased risk of...
The long QT syndrome may be acquired or genetically determined. The syndrome is characterized by a prolonged QT interval and is associated with an increased risk of cardiac arrhythmia such as a torsade de pointe and death. Electrolytes disorders such as hypomagnesemia and hypokaliemia and several drugs may increase the risk to develop a long QT syndrome. The epidemiology, the aetiology, the diagnostic approach as well as the management options of an acquired QT prolongation is discussed and reviewed herein.
Topics: Adult; Drug-Related Side Effects and Adverse Reactions; Electrocardiography; Female; Humans; Long QT Syndrome; Male; Middle Aged; Narcotics; Risk Factors
PubMed: 24024425
DOI: No ID Found -
Circulation Jun 1993
Topics: Adrenergic beta-Antagonists; Child; Electrocardiography; Humans; Infant, Newborn; Long QT Syndrome; Risk Factors
PubMed: 8099318
DOI: 10.1161/01.cir.87.6.2058 -
Heart Rhythm Oct 2020
Topics: Arrhythmias, Cardiac; Cardiac Conduction System Disease; Humans; Long QT Syndrome; NAV1.5 Voltage-Gated Sodium Channel
PubMed: 32497765
DOI: 10.1016/j.hrthm.2020.05.033