They cause syncope and sudden death in response to exercise or emotional stress, and can present with a sentinel event of sudden cardiac death in infancy. [uniprot.org]

Key words Long QT syndrome Neonatal presentation Syncope Ventricular arrhythmias This is a preview of subscription content, log in to check access. Preview Unable to display preview. Download preview PDF. References 1. [link.springer.com]

Long QT syndrome (LQTS) should be suspected in individuals on the basis of ECG characteristics, clinical presentation, and family history. [centogene.com]

Case presentation: We describe a 14-year-old boy with hypopituitarism after trans-sphenoidal surgery (TSS) due to suprasellar mass who manifested bradycardia and QT prolongation on electrocardiogram. [abstracts.eurospe.org]

This is likely an underestimate as sudden death with a normal autopsy may be the first and only presentation. There are 12 genes responsible for 3 main types of c-LQTS. The presentation is one of aborted sudden death or brief arrhythmia. [epmonthly.com]

• Sudden Infant Death Syndrome

  Abstract Prolongation of the QT interval is the cause of about 10% cases of sudden infant death syndrome (SIDS) in newborns but it is also responsible for about 5% of sudden deaths in adults. [omicsonline.org]

  Molecular diagnosis in a child with sudden infant death syndrome. Lancet 2001 ; 358 : 1342 –3. ↵ Haddad GG, Epstein MA, Epstein RA, et al. The QT interval in aborted sudden infant death syndrome infants. [adc.bmj.com]

  Relation with sudden infant deaths Sudden infant death syndrome (SIDS) remains the leading cause of sudden death during the first year of life in the western world. [ojrd.biomedcentral.com]

  […] including subarachnoid bleed Structural heart disease For syncope or sudden death in the young: Sudden infant death syndrome (SIDS) Drug-induced QT prolongation Vasovagal syncope (orthostatic hypotension) Anomalous coronary artery Familial ventricular [centogene.com]

  The sudden infant death syndrome gene: Does it exist? Pediatrics 114(4):e506-512, 2004. 4. Schwartz PJ, Stramba-Badiale M, Segantini A, et al. Prolongation of the QT interval and sudden infant death syndrome. N Engl J Med 338(24):1709-1714, 1998. 5. [emsworld.com]

• Falling

  This fall he presented to his pediatrician after having multiple syncopal events over a 2-week period. After careful inquiry, the physician discovered that the boy had been taking ketoconazole for a short time for a presumed fungal infection. [pedsinreview.aappublications.org]

  I ran a personal best half marathon that fall, about 9 months after my ICD placement. I consider us the lucky ones. [epmonthly.com]

  The concealed cases fall under the heading of a more general phenomenon of incomplete penetrance of all genetic disorders of the ion channels, while standing for a difficult diagnosis. [romanianjournalcardiology.ro]

  Any variants that fall outside these regions are not analyzed. Any specific limitations in the analysis of these genes are also listed in the table below. [invitae.com]

  A QTc greater than 460 ms is considered long. 6 As previously stated, females generally fall into the upper limit. Why Is LQTS Bad? The simple answer is the prolonged refractory period. [emsworld.com]

• Cough

  Symptoms are usually self-limited and variable and include cough (non-productive usually but later can be productive), fever, fatigue and occasionally headache. Coryza is rare. Cough can continue for 3 to 4 weeks and can be accompanied by wheezing. [pediatriceducation.org]

• Nausea

  She had no rhinorrhea, fever, nausea, vomiting or shortness of breath. Overall she just didn’t feel well but was attending school and doing her sports activities. [pediatriceducation.org]

  […] lengthen the QT interval and upset heart rhythm include: Certain antibiotics Certain antidepressant and antipsychotic medications Some antihistamines Diuretics Medications used to maintain normal heart rhythms (antiarrhythmic medications) Some anti-nausea [mayoclinic.org]

  Possible side effects of adrenaline infusion: Nausea Headache Palpitations Angina (if coronary artery disease also present) Hypo/hypertension Cardiac arrest. [inmo.ie]

  These sorrel formulations may cause nausea or vomiting when taken with the prescription drugs metronidazole (Flagyl®) or disulfiram (Antabuse®). Avoid if pregnant or breastfeeding. [livingnaturally.com]

• Vomiting

  She had no rhinorrhea, fever, nausea, vomiting or shortness of breath. Overall she just didn’t feel well but was attending school and doing her sports activities. [pediatriceducation.org]

  In addition, seek medical treatment right away for illnesses that could result in low blood-potassium levels, especially if you have a lot of vomiting and diarrhea. Such illnesses could trigger an episode of long QT syndrome. [mayoclinic.org]

  Diving and swimming are LQT 1 specific triggers 12 LQT2 – remove sources of loud noise (ie. alarm clocks/phone) Consult doctor before taking any new medications Carry disease ID card May need K supplement if diarrhoea and vomiting occurs Participation [inmo.ie]

  These sorrel formulations may cause nausea or vomiting when taken with the prescription drugs metronidazole (Flagyl®) or disulfiram (Antabuse®). Avoid if pregnant or breastfeeding. [livingnaturally.com]

• Heart Disease

  Congenital deaf mutism, functional heart disease with prolongation of the QT interval, and sudden death. Am Heart J. 1957;54:59-68. 4. Romano C, Gemme G, Pongiglione R. [Rare Cardiac Arrhythmias of the Pediatric Age. II. [revistas.uis.edu.co]

  Major clinical findings in LQTS-affected patients include the following: Abnormal QT values on ECG Prolonging of QT segments by specific drugs Hypokalemia Certain neurologic conditions including subarachnoid bleeding Structural heart disease Determination [centogene.com]

  They have been associated with abnormalities such as congenital heart disease, cognitive and behavioral problems, musculoskeletal diseases, and immune dysfunction. [emedicine.medscape.com]

  Braunwald’s heart disease: a textbook of cardiovascular medicine, 9th edition. Editors: Bonow RO, Mann DL, Zipes DP et al. Elsevier Saunders, Philadelphia, 2012,126-167. 37. Vetter VL. [romanianjournalcardiology.ro]

  Implications of implantable cardioverter defibrillator therapy in congenital heart disease and pediatrics. [ncbi.nlm.nih.gov]

• Hearing Impairment

  Avoiding medical evaluation for Jervell-Lange-Nielsen syndrome or any other hearing impairment related condition is not recommended. [californiaearinstitute.com]

• Fear

  I have realised in the last 5years that going through school and teens I allowed the lqt to restrict the things I did, and use it as an excuse partly due to fear. [healthunlocked.com]

  A majority of symptomatic events are triggered by situations of increased sympathetic nervous system output, such as physical activity emotional stress, anxiety, or fear. [anesthesiology.pubs.asahq.org]

  The massive release of catecholamines, triggered by pain and fear, that follows an ICD discharge in a conscious patient – especially a young one – leads to further arrhythmias and to further discharges which produce a dramatic vicious circle. [ojrd.biomedcentral.com]

  […] genotype-specific patterns in the type of trigger responsible for LQTS cardiac events. 5 Sixty-two percent of events in LQT1 patients occurred during exercise, especially swimming, and 43% of events in LQT2 patients were connected with episodes of emotional stress (fear [nature.com]

• Cesarean Section

  Br J Anaesth 1986; 58:575–6Palkar, NV Crawford, MW Ganta R, Roberts C, Elwood RJ, Maddineni VR: Epidural anesthesia for cesarean section in a patient with Romano-Ward syndrome. [anesthesiology.pubs.asahq.org]

• Seizure

  Case Studies SK is a 12-year-old girl who was diagnosed 1 year ago with a generalized seizure disorder. Both her mother and maternal uncle had histories of seizures. [pedsinreview.aappublications.org]

  Case report A 29 year-old Caucasian male, recently diagnosed with seizure disorder, was brought to emergency room for altered mental status with combative behavior. [jtd.amegroups.com]

  Other testing may include: Exercise stress test Ambulatory monitor Your doctor will also ask you if you have a: Family history of LQTS Family history of unexplained fainting, seizures, or cardiac arrest History of fainting, seizures or cardiac arrest, [my.clevelandclinic.org]

  Seizures. If the heart continues to beat erratically, the brain will eventually not get enough oxygen, which can cause seizures. Sudden death. Generally, the heart returns to its normal rhythm. [mayoclinic.org]

  This usually manifests as sudden, without warning syncope, near syncope or prolonged syncope with seizures. Many are misdiagnosed with seizure disorder or vasovagal syncope. [epmonthly.com]

• Stroke

  Use cautiously with asthma or a history of ulcers or stroke. Avoid if pregnant. Children should not take doses larger than what is commonly found in foods. [livingnaturally.com]

  Electrocardiographic changes in patients with acute stroke: a systematic review. Cerebrovasc Dis 2002 ; 14 : 67 –76. ↵ Filiano JJ, Kinney HC. [adc.bmj.com]

  Interferon-based therapy reduces risk of stroke in chronic hepatitis C patients: a population-based cohort study in Taiwan. Aliment Pharmacol Ther. 2013; 38 :415–423. [ PubMed ] [ Google Scholar ] 13. [ncbi.nlm.nih.gov]

  It accounts for one-third of strokes in patients over age 65. [nature.com]

The Mayo Clinic cases analyzed were anonymous samples derived from fetuses referred to the Mayo Clinic for chromosomal analysis as part of a workup for unexplained fetal death and were noted to be nonanomalous and found to be karyotypically normal. [jamanetwork.com]

• QTc Interval Prolonged

  Hypokalemia, hypocalcemia, and use of loop diuretics are risk factors for QTc interval prolongation. [4] LQTS has been recognized as mainly Romano-Ward syndrome (ie, familial occurrence with autosomal dominant inheritance, QT prolongation, and ventricular [emedicine.medscape.com]

  Most clinicians consider a corrected QT interval (QTc) of >440 msec for males and >450 msec for females to be prolonged. As the heart rate increases, the QT interval shortens. [uspharmacist.com]

• 2:1 Atrioventricular Block

  There is 2:1 atrioventricular block because the t wave has not even started when the next p wave appears; since ventricular repolarisation has not yet occurred, the ventricle cannot yet be depolarised again. [adc.bmj.com]

  […] strip showing 2:1 atrioventricular block secondary to prolongation of the QT interval. ( C ) A rhythm strip demonstrating polymorphic ventricular tachycardia. [pnas.org]

  B: atrioventricular block 2:1. C: self-limited torsade de pointes. [revespcardiol.org]

  Timothy syndrome may include a functional 2/1 atrioventricular block, due to an exceedingly long QT interval5,19,48. [romanianjournalcardiology.ro]

• Torsades De Pointes

  Torsade de pointes In LQTS, QT prolongation can lead to polymorphic ventricular tachycardia, or torsade de pointes, which itself may lead to ventricular fibrillation and sudden cardiac death. [emedicine.medscape.com]

  Electrocardiogram showing torsades de pointes. Note the more or less symmetric variation in the ventricular tachycardia waves. Torsades de pointes may resolve into sinus rhythm or progress into ventricular fibrillation. [ corrected ] FIGURE 3. [aafp.org]

  The long QT syndrome and torsade de pointes. Pacing and Clinical Electrophysiology 22(1), Pt 1:91-110, 1999. 9. Kirchhof P, Eckardt L, Franz MR, et al. [emsworld.com]

  The delayed recovery predisposes individuals to the development of early afterdepolarizations and initiation of torsade de pointes arrhythmias. The torsade produces the syncope and sudden death. [journals.lww.com]

  Drugs That Prolong the QT Interval and/or Induce Torsades de Pointes Table 1. Drugs That Prolong the QT Interval and/or Induce Torsades de Pointes × [anesthesiology.pubs.asahq.org]

• T Wave Alternans

  A 24-hour ambulatory ECG tracing was obtained in each individual. 5/14 patients with LQTS had pathological findings during ambulatory ECG monitoring (2 patients with episodes of torsade de pointes tachycardia, 2 patients with T-wave alternans and 1 patient [karger.com]

  Follow-up electrocardiograms and Holter records show persistent QT prolongation, bizarre T waves, and intermittent episodes of T wave alternans. On propranolol monotherapy the boy is thriving and completely free of ventricular arrhythmias. [link.springer.com]

  The severity of T-wave alternans tends to correlate with the risk of cardiac events. 10 View/Print Figure FIGURE 3. Electrocardiogram showing torsades de pointes. Note the more or less symmetric variation in the ventricular tachycardia waves. [aafp.org]

  […] morphological abnormalities and T-wave alternans ( Figure 1 ). [circ.ahajournals.org]

  In many cases the T-wave appears abnormal and this can be the only indication that someone is affected. For example the T wave may be larger, longer, notched, biphasic or have an alternans appearance. [inmo.ie]

Additionally, candidacy for cochlear implantation, currently the only medical treatment available for the treatment of profound sensorineural hearing loss, cannot be established without a comprehensive medical examination. [californiaearinstitute.com]

Recent studies suggest feasibility of genotype specific treatment of LQTS and, in near future, mutation specific treatment will probably become a novel approach to this potentially fatal syndrome. [jtd.amegroups.com]

It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care. Our staff consists of biologists and biochemists that are not trained to give medical advice . [uniprot.org]

Treatment includes beta-blockers and implantation of an implantable cardioverter defibrillator (ICD). [healio.com]

LTQTS subtypes influence the arrhythmia risk and also the choice of treatment including no specific treatment for some patients. [pediatriceducation.org]

In addition to an improved prognosis, we can better prepare for changes in a patient’s condition and triage them to more appropriate receiving facilities. How Do I Detect LQTS? As the name implies, simply measure the QT/QTc interval. [emsworld.com]

[…] may experience symptoms from as early as the first months of life to as late as middle age. 2 LQTS can be detected in children through ECG, although widespread routine screening in asymptomatic patients is not currently recommended in the U.S. 7 The prognosis [uspharmacist.com]

The relationship of heart rate variability with severity and prognosis of cirrhosis. Dig Dis Sci. 2006; 51 :1614–1618. [ PubMed ] [ Google Scholar ] 15. Hendrickse MT, Thuluvath PJ, Triger DR. [ncbi.nlm.nih.gov]

Large-scale epidemiologic studies have demonstrated an association between QTc prolongation and cardiac prognosis in patients with heart disease, though many studies lack appropriate adjustment for prior conditions. [nature.com]

Two-to-one AV block is an infrequent manifestation with a poor prognosis that can be present since the fetal stage in the form of persistent bradycardia. [revespcardiol.org]

[…] taught in most EMS curricula and may be overlooked. 1 This condition is identified by a long QT interval on an electrocardiogram (ECG) and may be congenital or medication-induced. 2 An increasing number of sudden cardiac arrests with previously unknown etiology [emsworld.com]

Clinical features and etiology of hepatocellular carcinoma arising in patients with membranous obstruction of the inferior vena cava: in reference to hepatitis viral infection. [ncbi.nlm.nih.gov]

Advances in molecular and genetic cardiology over the past 20 years, coupled with increasing awareness of inherited conditions in the etiology of sudden cardiac death, have moved LQTS from the periphery to mainstream clinical medicine. [circ.ahajournals.org]

It presents when the QT interval is prolonged, regardless of the etiology. It is a polymorphic ventricular tachycardia due to reentry, characterized electrocardiographically by continuous twisting of the QRS axis around an imaginary line. [revespcardiol.org]

Etiology of sudden death in an apparently normal heart (7-10) Congenital LQTS inside the genetic anomalies of the ion channels So far, there is a spectrum of inherited arrhythmia syndromes arising from genetic defects in structures involved in the genesis [romanianjournalcardiology.ro]

Epidemiological studies of SIDS have shown some link to sedative medications, but not yet to ingestion of QT prolonging medications. [adc.bmj.com]

Sudden infant death syndrome and long QT syndrome: an epidemiological and genetic study. Int J Legal Med. 2006; 120 :129–37. [ PubMed : 16012827 ] Westenskow P, Splawski I, Timothy KW, Keating MT, Sanguinetti MC. [ncbi.nlm.nih.gov]

American Journal of Epidemiology, 170, 739-746. doi:10.1093/aje/kwp191 Van Noord, C., Sturkenboom, M.C., Straus, S.M., Hofman, A., Kors, J.A., Witteman, J.C. and Stricker, B.H. (2010). [file.scirp.org]

Investigative teams have published comprehensive clinical-epidemiologic reviews of both long QT syndrome as a family and several of the other channelopathies under Human Genome Epidemiology (HuGE) reviews (e.g., long QT syndrome 21 ) and GeneReviews [currents.plos.org]

The genetic epidemiology of both forms can vary with subpopulation depending on the allele, but as a whole, LQTS appears in every corner of the globe. [nature.com]

Pathophysiology of hepatic dysfunction and intrahepatic cholestasis in heart failure and after left ventricular assist device support. J Heart Lung Transplant. 2005; 24 :361–370. [ PubMed ] [ Google Scholar ] 122. [ncbi.nlm.nih.gov]

The pathophysiological basis of long-QT syndrome (LQTS) is prolongation of cardiac ventricular repolarization by acquired factors such as drug exposure or genetic variation in the proteins controlling transmembrane ion-concentration gradients ( 8, 9 ) [pnas.org]

The role of the sympathetic nervous system in the long QT syndrome: the long road from pathophysiology to therapy. Long QT syndrome. Cardiac Electrophysiology Clinics, volume 4, number 1. Editors: Priori SG, Thakur RK, Natale A. [romanianjournalcardiology.ro]

"Molecular Pathophysiology of Congenital Long QT Syndrome". Physiological Reviews. 97 (1): 89–134. doi : 10.1152/physrev.00008.2016. PMC 5539372. PMID 27807201. ^ a b Giudicessi JR, Ackerman MJ (October 2013). [en.wikipedia.org]

Appropriate therapy will prevent unnecessary deaths in infants, children, and young adults. [omicsonline.org]

Conclusion: This case highlights that hormonal disorders should be considered as a cause of arrhythmia or prolongation of QT intervals and this can be prevented and cured by appropriate hormone replacement therapy. [abstracts.eurospe.org]

June 13, 2017 WIRED: A Radical Proposal For Preventing Rare Genetic Diseases Read More April 14, 2017 Parent of a Medically Complex Child, “I am Always Choosing Between the Lesser… Read More November 23, 2013 Martial Arts Expert Suffers From Andersen-Tawil [globalgenes.org]

Prophylactic β-blocker therapy was started in these two patients to prevent sudden death. In conclusion, this syndrome should be sought in children with syncope or a family history of it, especially those with congenital deafness. [link.springer.com]

This information is important because it supports the need to consider implanting an ICD for secondary prevention of CA even in young SQTS patients. Anttonen O, Junttila J, Giustetto C, et al. T-Wave morphology in short QT syndrome. [e-cardiogram.com]