keyword
MENU ▼
Read by QxMD icon Read
search

LQTS

keyword
https://www.readbyqxmd.com/read/27882731/reproducibility-of-corrected-qt-interval-in-pediatric-genotyped-long-qt-syndrome
#1
Yoshiharu Ogawa, Toshikatsu Tanaka, Sachiko Kido
Reproducibility of corrected QT interval (QTc), especially QTc after exercise, has not been thoroughly investigated. We reviewed charts of pediatric patients who underwent treadmill-exercise stress testing without medication multiple times within 1 year. In patients with long-QT syndrome (LQTS; n = 22), the discrepancy in QTc between two treadmill exercise stress tests using Fridericia's formula was 14 ± 12 ms at rest, 13 ± 12 ms 4 min after exercise, with a maximum of 14 ± 12 ms after exercise. There was no statistically significant difference in QTc between the two tests...
November 2016: Pediatrics International: Official Journal of the Japan Pediatric Society
https://www.readbyqxmd.com/read/27871843/considerations-when-using-next-generation-sequencing-for-genetic-diagnosis-of-long-qt-syndrome-in-the-clinical-testing-laboratory
#2
Hyojin Chae, Jiyeon Kim, Gun Dong Lee, Woori Jang, Joonhong Park, Dong Wook Jekarl, Yong Seog Oh, Myungshin Kim, Yonggoo Kim
BACKGROUND: Congenital long-QT syndrome (LQTS) is a potentially lethal cardiac electrophysiologic disorder characterized by QT interval prolongation and T-wave abnormalities. At least 13 LQTS-associated genes have been reported, but the high cost and low throughput of conventional Sanger sequencing has hampered the multi-gene-based LQTS diagnosis in clinical laboratories. METHODS: We developed an NGS (next-generation sequencing)-based targeted gene panel for 13 LQTS genes using the Ion PGM platform, and a cohort of 36 LQTS patients were studied for characterization of analytical performance specifications...
November 18, 2016: Clinica Chimica Acta; International Journal of Clinical Chemistry
https://www.readbyqxmd.com/read/27861123/tecrl-a-new-life-threatening-inherited-arrhythmia-gene-associated-with-overlapping-clinical-features-of-both-lqts-and-cpvt
#3
Harsha D Devalla, Roselle Gélinas, Elhadi H Aburawi, Abdelaziz Beqqali, Philippe Goyette, Christian Freund, Marie-A Chaix, Rafik Tadros, Hui Jiang, Antony Le Béchec, Jantine J Monshouwer-Kloots, Tom Zwetsloot, Georgios Kosmidis, Frédéric Latour, Azadeh Alikashani, Maaike Hoekstra, Jurg Schlaepfer, Christine L Mummery, Brian Stevenson, Zoltan Kutalik, Antoine Af de Vries, Léna Rivard, Arthur Am Wilde, Mario Talajic, Arie O Verkerk, Lihadh Al-Gazali, John D Rioux, Zahurul A Bhuiyan, Robert Passier
Genetic causes of many familial arrhythmia syndromes remain elusive. In this study, whole-exome sequencing (WES) was carried out on patients from three different families that presented with life-threatening arrhythmias and high risk of sudden cardiac death (SCD). Two French Canadian probands carried identical homozygous rare variant in TECRL gene (p.Arg196Gln), which encodes the trans-2,3-enoyl-CoA reductase-like protein. Both patients had cardiac arrest, stress-induced atrial and ventricular tachycardia, and QT prolongation on adrenergic stimulation...
December 1, 2016: EMBO Molecular Medicine
https://www.readbyqxmd.com/read/27844191/-indications-for-implantable-loop-recorders-in-patients-with-channelopathies-and-ventricular-tachycardias
#4
Julia Köbe, Kristina Wasmer, Florian Reinke, Lars Eckardt
Implantable loop recorders (ILR) do not play a pivotal role in the current guidelines on ventricular arrhythmias except in identifying rhythm-symptom correlations if ventricular arrhythmias are assumed. Before a decision for a pure diagnostic implantable device is made, a thorough arrhythmic risk assessment is of major importance due to the potential lethal outcome of ventricular arrhythmias. Nevertheless, some clinical circumstances exist where long-term monitoring by an ILR may add significant information in electrical heart diseases, in patients with ventricular arrhythmias, or structural heart diseases and a potential risk of ventricular arrhythmias...
November 14, 2016: Herzschrittmachertherapie & Elektrophysiologie
https://www.readbyqxmd.com/read/27826330/management-of-patients-with-long-qt-syndrome
#5
REVIEW
Yongkeun Cho
Long QT syndrome (LQTS) is a rare cardiac channelopathy associated with syncope and sudden death due to torsades de pointes and ventricular fibrillation. Syncope and sudden death are frequently associated with physical and emotional stress. Management of patients with LQTS consists of life-style modification, β-blockers, left cardiac sympathetic denervation (LCSD), and implantable cardioverter-defibrillator (ICD) implantation. Prohibition of competitive exercise and avoidance of QT-prolonging drugs are important issues in life-style modification...
November 2016: Korean Circulation Journal
https://www.readbyqxmd.com/read/27816319/contribution-of-a-kcnh2-variant-in-genotyped-long-qt-syndrome-romano-ward-syndrome-under-double-mutations-and-acquired-long-qt-syndrome-under-heterozygote
#6
Yusuke Fujii, Yuichi Matsumoto, Kenshi Hayashi, Wei-Guang Ding, Yukinori Tomita, Daisuke Fukumoto, Yuko Wada, Mari Ichikawa, Keiko Sonoda, Junichi Ozawa, Takeru Makiyama, Seiko Ohno, Masakazu Yamagishi, Hiroshi Matsuura, Minoru Horie, Hideki Itoh
BACKGROUND: Long QT syndrome (LQTS) presents two clinical phenotypes, congenital and acquired forms. This study aims to evaluate the genetic contribution of a KCNH2 variant for the two LQTS phenotypes. METHODS: From 1996 to 2014, genetic screening for LQTS probands was performed for five major genes: KCNQ1, KCNH2, SCN5A, KCNE1, and KCNE2 and 389 probands were found to be mutation carriers. We analyzed the clinical phenotypes of p.His492Tyr carriers in KCNH2. RESULTS: Heterozygous p...
November 2, 2016: Journal of Cardiology
https://www.readbyqxmd.com/read/27815504/the-arrhythmogenic-calmodulin-mutation-d129g-dysregulates-cell-growth-calmodulin-dependent-kinase-ii-activity-and-cardiac-function-in-zebrafish
#7
Martin W Berchtold, Triantafyllos Zacharias, Katarzyna Kulej, Kevin Wang, Raffaela Torggler, Thomas Jespersen, Jau-Nian Chen, Martin R Larsen, Jonas M La Cour
Calmodulin (CaM) is a Ca2+ binding protein modulating multiple targets of which several are associated with cardiac pathophysiology. Recently, CaM mutations were linked to heart arrhythmia. CaM is crucial for cell growth and viability, yet the effect of the arrhythmogenic CaM mutations on cell viability as well as heart rhythm remains unknown and only a few targets with relevance for heart physiology have been analyzed for their response to mutant CaM. We show that the arrhythmia-associated CaM mutants support growth and viability of DT40 cells in the absence of wt CaM except for the LQTS mutant CaM D129G...
November 4, 2016: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/27810088/the-promise-and-peril-of-precision-medicine-phenotyping-still-matters-most
#8
REVIEW
Jaeger P Ackerman, Daniel C Bartos, Jamie D Kapplinger, David J Tester, Brian P Delisle, Michael J Ackerman
We illustrate the work necessary to reverse course after identification of a KCNQ1 variant interpreted erroneously as causing long QT syndrome (LQTS) and to identify the true cause of a case of sudden death in the young. Surrogate genetic testing of a decedent's living brother identified a rare KCNQ1-V133I variant, which prompted an implantable cardioverter defibrillator and subsequent diagnosis of LQTS in other family members. Subsequently, this presumed LQT1 family came to our institution for further clinical evaluation and research-based investigations, including KCNQ1-V133I variant-specific analysis of the decedent, heterologous expression studies of KCNQ1-V133I, and a whole-exome molecular autopsy along with genomic triangulation using his unaffected parents' DNA...
October 8, 2016: Mayo Clinic Proceedings
https://www.readbyqxmd.com/read/27784853/phenotypic-variability-of-ank2-mutations-in-patients-with-inherited-primary-arrhythmia-syndromes
#9
Mari Ichikawa, Takeshi Aiba, Seiko Ohno, Daichi Shigemizu, Junichi Ozawa, Keiko Sonoda, Megumi Fukuyama, Hideki Itoh, Yoshihiro Miyamoto, Tatsuhiko Tsunoda, Takeru Makiyama, Toshihiro Tanaka, Wataru Shimizu, Minoru Horie
BACKGROUND: Mutations inANK2have been reported to cause various arrhythmia phenotypes. The prevalence ofANK2mutation carriers in inherited primary arrhythmia syndrome (IPAS), however, remains unknown in Japanese. Using a next-generation sequencer, we aimed to identifyANK2mutations in our cohort of IPAS patients, in whom conventional Sanger sequencing failed to identify pathogenic mutations in major causative genes, and to assess the clinical characteristics ofANK2mutation carriers.Methods and Results:We screened 535 probands with IPAS and analyzed 46 genes including wholeANK2exons using a bench-top NGS (MiSeq, Illumina) or performed whole-exome-sequencing using HiSeq2000 (Illumina)...
October 25, 2016: Circulation Journal: Official Journal of the Japanese Circulation Society
https://www.readbyqxmd.com/read/27765793/a-precision-medicine-approach-to-the-rescue-of-function-on-malignant-calmodulinopathic-long-qt-syndrome
#10
Worawan B Limpitikul, Ivy E Dick, David Tester, Nicole J Boczek, Pattraranee Limphong, Wanjun Yang, Myoung Hyun Choi, Jennifer Babich, Deborah DiSilvestre, Ronald J Kanter, Gordon F Tomaselli, Michael J Ackerman, David Yue
RATIONALE: Calmodulinopathies comprise a new category of potentially life-threatening genetic arrhythmia syndromes capable of producing severe long QT syndrome (LQTS) with mutations involving either CALM1, CALM2, or CALM3 The underlying basis of this form of LQTS is a disruption of Ca(2+)/CaM-dependent inactivation (CDI) of L-type Ca(2+) channels (LTCCs). OBJECTIVE: To gain insight into the mechanistic underpinnings of calmodulinopathies and devise new therapeutic strategies for the treatment of this form of LQTS...
October 20, 2016: Circulation Research
https://www.readbyqxmd.com/read/27761161/molecular-pathogenesis-of-long-qt-syndrome-type-2
#11
Jennifer L Smith, Corey L Anderson, Don E Burgess, Claude S Elayi, Craig T January, Brian P Delisle
The molecular mechanisms underlying congenital long QT syndrome (LQTS) are now beginning to be understood. New insights into the etiology and therapeutic strategies are emerging from heterologous expression studies of LQTS-linked mutant proteins, as well as inducible pluripotent stem cell derived cardiomyocytes (iPSC-CMs) from LQTS patients. This review focuses on the major molecular mechanism that underlies LQTS type 2 (LQT2). LQT2 is caused by loss of function (LOF) mutations in KCNH2 (also known as the human Ether-à-go-go-Related Gene or hERG)...
October 2016: Journal of Arrhythmia
https://www.readbyqxmd.com/read/27761159/molecular-autopsy-in-victims-of-inherited-arrhythmias
#12
Christopher Semsarian, Jodie Ingles
Sudden cardiac death (SCD) is a rare but devastating complication of a number of underlying cardiovascular diseases. While coronary artery disease and acute myocardial infarction are the most common causes of SCD in older populations, inherited cardiac disorders comprise a substantial proportion of SCD cases aged less than 40 years. Inherited cardiac disorders include primary inherited arrhythmogenic disorders such as familial long QT syndrome (LQTS), Brugada syndrome (BrS), catecholaminergic polymorphic ventricular tachycardia (CPVT), and inherited cardiomyopathies, most commonly hypertrophic cardiomyopathy (HCM)...
October 2016: Journal of Arrhythmia
https://www.readbyqxmd.com/read/27761156/left-cardiac-sympathetic-denervation-an-important-treatment-option-for-patients-with-hereditary-ventricular-arrhythmias
#13
Yongkeun Cho
Medications such as ß-blockers are currently the primary treatment for patients with hereditary arrhythmia syndromes such as long QT syndrome (LQTS) and catecholaminergic polymorphic ventricular tachycardia (CPVT). However, these drugs are ineffective in some patients, and the other treatment option, that is implantable cardioverter defibrillator (ICD) implantation, is associated with significant complications in young and active patients. Left cardiac sympathetic denervation (LCSD) may reduce the wide gap between life-long ß-blocker medication and ICD implantation...
October 2016: Journal of Arrhythmia
https://www.readbyqxmd.com/read/27723808/time-to-onset-analysis-of-drug-induced-long-qt-syndrome-based-on-a-spontaneous-reporting-system-for-adverse-drug-events
#14
Sayaka Sasaoka, Toshinobu Matsui, Yuuki Hane, Junko Abe, Natsumi Ueda, Yumi Motooka, Haruna Hatahira, Akiho Fukuda, Misa Naganuma, Shiori Hasegawa, Yasutomi Kinosada, Mitsuhiro Nakamura
Long QT syndrome (LQTS) is a disorder of the heart's electrical activity that infrequently causes severe ventricular arrhythmias such as a type of ventricular tachycardia called torsade de pointes (TdP) and ventricular fibrillation, which can be fatal. There have been no previous reports on the time-to-onset for LQTS based on data from spontaneous reporting systems. The aim of this study was to assess the time-to-onset of LQTS according to drug treatment. We analyzed the association between 113 drugs in 37 therapeutic categories and LQTS including TdP using data obtained from the Japanese Adverse Drug Event Report database...
2016: PloS One
https://www.readbyqxmd.com/read/27702859/antiarrhythmic-effect-of-vernakalant-in-an-experimental-model-of-long-qt-syndrome
#15
Gerrit Frommeyer, Catharina Clauss, Christian Ellermann, Harilaos Bogossian, Dirk G Dechering, Simon Kochhäuser, Florian Reinke, Christian Pott, Lars Eckardt
AIMS: The antiarrhythmic drug vernakalant exerts antiarrhythmic effects in atrial fibrillation. Recent experimental data suggest interactions with the late sodium current and antiarrhythmic effects in ventricular arrhythmias. We aimed at investigating whether treatment with vernakalant reduces polymorphic ventricular tachycardia (VT) in an experimental model of Long-QT-syndrome (LQTS). METHODS AND RESULTS: Twenty-nine isolated rabbit hearts were assigned to two groups and treated with erythromycin (300 µM, n = 15) or veratridine (0...
October 4, 2016: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
https://www.readbyqxmd.com/read/27681629/early-somatic-mosaicism-is-a-rare-cause-of-long-qt-syndrome
#16
James Rush Priest, Charles Gawad, Kristopher M Kahlig, Joseph K Yu, Thomas O'Hara, Patrick M Boyle, Sridharan Rajamani, Michael J Clark, Sarah T K Garcia, Scott Ceresnak, Jason Harris, Sean Boyle, Frederick E Dewey, Lindsey Malloy-Walton, Kyla Dunn, Megan Grove, Marco V Perez, Norma F Neff, Richard Chen, Katsuhide Maeda, Anne Dubin, Luiz Belardinelli, John West, Christian Antolik, Daniela Macaya, Thomas Quertermous, Natalia A Trayanova, Stephen R Quake, Euan A Ashley
Somatic mosaicism, the occurrence and propagation of genetic variation in cell lineages after fertilization, is increasingly recognized to play a causal role in a variety of human diseases. We investigated the case of life-threatening arrhythmia in a 10-day-old infant with long QT syndrome (LQTS). Rapid genome sequencing suggested a variant in the sodium channel NaV1.5 encoded by SCN5A, NM_000335:c.5284G > T predicting p.(V1762L), but read depth was insufficient to be diagnostic. Exome sequencing of the trio confirmed read ratios inconsistent with Mendelian inheritance only in the proband...
October 11, 2016: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/27663173/convergence-of-models-of-human-ventricular-myocyte-electrophysiology-after-global-optimization-to-recapitulate-clinical-long-qt-phenotypes
#17
Stefan A Mann, Mohammad Imtiaz, Annika Winbo, Annika Rydberg, Matthew D Perry, Jean-Philippe Couderc, Bronislava Polonsky, Scott McNitt, Wojciech Zareba, Adam P Hill, Jamie I Vandenberg
In-silico models of human cardiac electrophysiology are now being considered for prediction of cardiotoxicity as part of the preclinical assessment phase of all new drugs. We ask the question whether any of the available models are actually fit for this purpose. We tested three models of the human ventricular action potential, the O'hara-Rudy (ORD11), the Grandi-Bers (GB10) and the Ten Tusscher (TT06) models. We extracted clinical QT data for LQTS1 and LQTS2 patients with nonsense mutations that would be predicted to cause 50% loss of function in IKs and IKr respectively...
September 20, 2016: Journal of Molecular and Cellular Cardiology
https://www.readbyqxmd.com/read/27650425/female-gender-as-independent-risk-factor-of-torsades-de-pointes-during-acquired-atrioventricular-block
#18
Ehud Chorin, Aviram Hochstadt, Sami Viskin, Uri Rozovski, Ofer Havakuk, Adrian Baranchuk, Andres Enriquez, Boris Strasberg, Milton E Guevara-Valdivia, Manlio F Márquez, Héctor González-Pacheco, Can Hasdemir, Raphael Rosso
BACKGROUND: Female gender increases the risk of torsades de pointes (TdP) in the long QT syndrome, and this increased risk is assumed to be due to their longer QT interval. OBJECTIVE: The purpose of this study was to study the interplay between gender, duration of the QT interval, and risk of TdP during AV block. METHODS: We studied 250 patients (48% women) with AV block. QT interval was measured at the time of most severe bradycardia. We then constructed different receiver operating characteristic curves for the QTc of males and females for predicting TdP...
September 17, 2016: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/27626620/the-emerging-role-of-calmodulin-regulation-of-ryr2-in-controlling-heart-rhythm-the-progression-of-heart-failure-and-the-antiarrhythmic-action-of-dantrolene
#19
Kafa Walweel, Ye Win Oo, Derek R Laver
Cardiac output and rhythm depend on the release and the take-up of calcium from the sarcoplasmic reticulum (SR). Excessive diastolic calcium leak from the SR due to dysfunctional calcium release channels (RyR2) contributes to the formation of delayed after-depolarisations, which underlie the fatal arrhythmias that occur in heart failure and inherited syndromes. Calmodulin (CaM) is a calcium-binding protein that regulates target proteins and acts as a calcium sensor. CaM is comprised of two calcium binding EF-hand domains and a flexible linker...
September 14, 2016: Clinical and Experimental Pharmacology & Physiology
https://www.readbyqxmd.com/read/27613431/mutation-analysis-for-the-detection-of-long-qt-syndrome-lqts-associated-snps
#20
Edelmann J, Dobosz T, Sobieszczanska M, Kawecka-Negrusz M, Dreßler J, Nastainczyk-Wulf M
Congenital long QT-syndrome (LQTS) is an inherited cardiac arrhythmia, which is characterized by a prolonged QT interval which predisposes to sudden cardiac death due to ventricular arrhythmias. The altered functions are based on different mutations in LQTS-associated genes. In this study, we performed a mutation analysis for the detection of 125 LQTS-associated single nucleotide polymorphisms (SNPs) focused on the genes KCNQ1, KCNH2, and SCN5A by using the SNaPshot multiplex minisequencing technique. Furthermore, we investigated 152 autopsy-negative cases from younger adults and infants, as well as samples from patients with clinically suspicion for LQTS, in which we found two types of variations...
September 9, 2016: International Journal of Legal Medicine
keyword
keyword
44568
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"