Presentation
Treatment includes beta-blockers, however if syncope or sustained ventricular arrhythmias are present, an implantable cardioverter defibrillator (ICD) is indicated to prevent sudden cardiac death. [healio.com]
Case presentation We report the case of a 10-year-old Moroccan boy with congenital hearing loss and severely prolonged QT interval who presented with multiple episodes of syncope. His parents are first-degree cousins. [jmedicalcasereports.biomedcentral.com]
Torsade de Pointes with severe vitamin D deficiency, an unusual presentation of a common problem. [amboss.com]
This study presents biallelic gene mutations in KCNQ1 in Asian Indian patients with AR JLNS and RWS. It adds to the scant worldwide literature of mutation studies in AR RWS. © 2016 Wiley Periodicals, Inc. [pubmed.ncbi.nlm.nih.gov]
By contrast, no significant difference was present among LQT2 and LQT3 patients despite a trend in the same direction. [ahajournals.org]
Entire Body System
- Camping
Sanguinetti MC 15051636 2004 48 Novel compound heterozygous mutations in the KCNQ1 gene associated with autosomal recessive long QT syndrome (Jervell and Lange-Nielsen syndrome). 61 25 Ning L...Qi M 14510661 2003 49 Requirement of subunit expression for cAMP-mediated [malacards.org]
Either way, the proposed involvement of both early and delayed afterdepolarizations provides a rationale for the use of β-BRs as these drugs counteract loading of intracellular Ca2+ stores by cAMP-dependent processes.43 Summary of Recent Advancements [revespcardiol.org]
Ears
- Tinnitus
Cited by 4 articles Clinical and Genome-wide Analysis of Cisplatin-induced Tinnitus Implicates Novel Ototoxic Mechanisms. [pubmed.ncbi.nlm.nih.gov]
Workup
QT, RR, ST Intervals
- Prolonged QT Interval
Jervell-Lange-Nielsen Syndrome is a genetic condition associated with a prolonged QT interval on the ECG and conginital hearing loss. A mutation of the cardiac potassium channel is responsible, specifically the KCNQ1 (90%) and KCNE1 (10%) genes. [healio.com]
Etiology A prolonged QT interval may be congenital or acquired. [amboss.com]
QT interval with ventricular tachyarrhythmias. [asperbio.com]
[…] heart disease with prolongation of the Q-T interval and sudden death. [statpearls.com]
QT interval in EKG and sudden death Surdo-cardiac syndrome References Mizusawa Y, Horie M, Wilde AA. [medlineplus.gov]
Treatment
We discuss diagnosis and management of this syndrome and also the long-term performance of cochlear implantation in these Iranian patients, referring especially to the role of the ENT specialist in diagnosis and treatment. [cambridge.org]
Treatment depends on the underlying cause: Beta blockers and implantable cardioverter defibrillator (ICD) insertion are commonly used for congenital LQTS, whereas treatment of the underlying cause (drug, electrolyte abnormality, etc.) is the first-line [amboss.com]
However, treatment with beta blockers markedly reduces the risk of death, as does, in selected cases, implantation of a defibrillator. [owlapps.net]
Treatment includes beta-blockers, however if syncope or sustained ventricular arrhythmias are present, an implantable cardioverter defibrillator (ICD) is indicated to prevent sudden cardiac death. [healio.com]
However, recently treatment with an implantable automatic cardioverter-defibrillator (ICD) has replaced sympathectomy as the treatment of choice in these individuals. [rarediseases.org]
Prognosis
Myocardial problems such as myopathies and ischemia and central nervous system injuries.[12] Prognosis More than half of untreated children with JLNS die before age 15.[2] Prognosis is highly dependent on which gene is mutated, gender, and baseline QTc [statpearls.com]
However, the prognosis is generally regarded as poor as most of the untreated patients die around the age of 15 years.[46] The prognosis varies with the gender, gene mutation and baseline QTc interval. [wikidoc.org]
Prognosis The risk of arrhythmias is higher for those with Jervell and Lange-Nielsen syndrome than other forms of long QT syndrome. [owlapps.net]
Etiology
There was a marked prolongation of the QT interval on electrocardiographic studies with no other identifiable cause for the patient’s fainting spells.[1] Etiology JLNS is a congenital disorder that is inherited in an autosomal recessive manner. [statpearls.com]
Etiology A prolonged QT interval may be congenital or acquired. [amboss.com]
[…] white infants.28 Given the growing consistency of these and other29 molecular autopsy reports, the challenge is to find a cost-effective and efficient means for presymptomatic detection of LQTS to reduce the morbidity and mortality of the subset of SIDS etiologically [revespcardiol.org]
↑ ACMG (2002) Genetics Evaluation Guidelines for the Etiologic Diagnosis of Congenital Hearing Loss. Genetic Evaluation of Congenital Hearing Loss Expert Panel. ACMG statement. Genet Med 4 (3):162-71. [wikidoc.org]
Epidemiology
Epidemiology Jervell and Lange-Nielsen syndrome affects an estimated one in 166,000 to 625,000 children, and is responsible for less than 10% of all cases of long QT syndrome. [owlapps.net]
"Current concepts in age-related hearing loss: epidemiology and mechanistic pathways". Hear Res. 303: 30–8. doi:10.1016/j.heares.2013.01.021. PMC 3723756. [wikidoc.org]
Most cases are due to deletion mutations in the KCNQ1 (90%) and KCNE1 genes, which encode proteins essential in the potassium channels' functions in the heart and cochlea.[2] Epidemiology The prevalence of the disorder highly depends on the population [statpearls.com]
Pathophysiology
Review the pathophysiology of Jervell and Lange Nielsen Syndrome. Outline the interprofessional team's strategies for improving care coordination and communication regarding the management of patients with Jervell and Lange Nielsen syndrome. [statpearls.com]
Acquired Long QT Syndrome: Definitions, Causes, and Pathophysiology. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/acquired-long-qt-syndrome .Last updated: January 3, 2018. Accessed: December 6, 2017. [amboss.com]
Electrophysiological analysis of sodium current demonstrated that mutant CAV-3 results in a 2- to 3-fold increase in late sodium current compared with wild-type CAV-3, a pathophysiological mechanism well established to cause QT prolongation.20 Distribution [revespcardiol.org]
Locus Gene Mutation Protein Involved Jervell and Lange-Nielsen syndrome 1 11p15.5-p15.4 KCNQ1 Potassium voltage-gated channel subfamily KQT member 1 Jervell and Lange-Nielsen syndrome 2 21q22.12 KCNE1 Potassium voltage-gated channel subfamily E member 1 Pathophysiology [wikidoc.org]
Prevention
Propranolol and nadolol have been shown to be superior to metoprolol in preventing cardiac events. [statpearls.com]
Treatment includes beta-blockers, however if syncope or sustained ventricular arrhythmias are present, an implantable cardioverter defibrillator (ICD) is indicated to prevent sudden cardiac death. [healio.com]
Mutations in these genes alter the usual structure and function of potassium channels or prevent the assembly of normal channels. [medlineplus.gov]
prevention of Jervell and Lange-Nielsen syndrome (JLNS). [wikidoc.org]