View clinical trials related to Long QT Syndrome.
Filter by:Cardiac channelopathies induce severe heart rhythm or conduction disorders. Mutations of the KCNH2 gene, that encodes the human (h) ERG channel, is responsible for 30-40% of all cases of long QT syndrome (inherited LQT2). Besides, hERG is frequently responsible for off-target effects of several pharmacological agents (acquired LQT2). With the advent of Next Generation Sequencing, hundreds of new KCNH2 variants are accumulating in regional databases including those developed by french centers of references. Worldwide, we estimate there are more than 1000 variants for hERG channel. Unfortunately, many of these new variants appear to be of unknown functional significance in spite of available clinical and genetic information. Little is known on whether they affect the channel biophysical properties, its expression at the cell surface and/or its structure. Yet, this information is crucial to determine the real degree of pathogenicity of these variants, and therefore to make the proper diagnosis on inherited LQT2, counsel the patient for his treatment and improve the management of the patient's life. Our ambition is therefore to tackle this issue of variant significance by (i) launching a large-scale multi-functional evaluation of hERG variants, (ii) introducing for the first time a formatted large-scale pathogenicity annotation score for all variants that have been functionally evaluated by this multi-parametric approach, and (iii) regrouping all the relevant information collected in every French Regional centers of reference into a single National database hosted by an infrastructure that possesses enough flexibility for continuous data implementation and cross-referencing. The database will integrate the latest International guidelines for functional pathogenicity annotation. This project will also include the pharmacological characterization of several drugs susceptible to produce acquired LQT2 with variable severities. We aim to understand whether there are structural regions within hERG channel in which the introduction of a variant is more prone to increase the risk of acquired LQT2 or if, on the contrary, a set of variants may relatively protect some patients against LQT2-inducing drugs.
Part 1: This is a Phase 1b, randomized, double-blind, crossover, dose escalation, placebo-controlled study to evaluate the effect of oral LQT-1213 on dofetilide-induced QTc prolongation in healthy adult subjects. This is a 2-treatment, 2-period crossover study with approximately up to 28 healthy subjects, with screening procedures within 28 days of enrolment. Part 2: This is a Phase 2a, single-blind, placebo run-in, multiple-dose safety study to evaluate the safety, tolerability, and PK of LQT-1213 in patients diagnosed with LQT2 or LQT3. Up to 12 participants with LQT2 and up to 12 participants with LQT3 will be recruited.
The "Long-term Outcome and Predictors for Recurrence after Medical and Interventional Treatment of Arrhythmias at the University Heart Center Hamburg" (TRUST) study is an investor-initiated, single-center, prospective clinical cohort study including patients treated with cardiac arrhythmias or at high risk for cardiac arrhythmias. The design enables prospective, low-threshold, near complete inclusion of patients with arrhythmias treated at the UHZ. Collection of routine follow-up data, detailed procedural information and systematic biobanking will enable precise and robust phenotyping.
An important aspect of successful genomic medicine implementation is developing effective approaches for screening at-risk family members after probands are identified, also known as cascade screening. Most cascade screening studies conducted to date have been conducted outside the US, and very few studies have used a rigorous approach involving a comparator group or randomized controlled design. A major question in the field is how to most effectively implement cascade screening, given commonly cited communication barriers, while respecting privacy among probands and family members. This study will conduct a randomized controlled trial to assess direct contact of relatives by study team members vs indirect, or proband-initiated, contact. We will assess efficacy of the cascade screening intervention, patient-centered outcomes regarding mental, physical, and psychosocial outcomes in probands and family members, and implementation evaluation outcomes. Individuals who are known to carry the KCNQ1 Met224Thr or APOB Arg3527Gln variant will be eligible to participate. After providing consent and being deemed eligible, individuals will be randomized in a 1:1 manner into the direct or indirect contact of family members arm of the study. The randomization will be stratified by variant to ensure equal representation of each variant in the study arms. Individuals in the indirect arm will be instructed to contact their first-degree family members about the opportunity to be screened. They will be provided with a disease-specific pamphlet and a family letter explaining the cascade screening. In the direct arm, probands will be advised that the study staff will be contacting their family members. They will be instructed to also contact their family members prior to the study team contacting them. Approximately two weeks after this meeting with the proband, the study staff will mail letters to eligible first-degree family members of the probands. If we do not hear back from individual family members, we will follow-up with another letter, telephone call, or home visit. The information contained in the letters will be the same information for both the direct and indirect arms of the study. All interested family members will receive pre-test counseling and free, in-home, saliva-based genetic testing, and post-test counseling.
In patients expressing the SCN5A-E1784K mutation (Glu1784Lys), cardiovascular risk is difficult to define as the stratification of these patients is challenging. From our experience, major cardiovascular events (MCE) tend to occur more frequently in patients expressing overlap syndrome phenotype (Brugada syndrome and Long QT syndrome type 3)than in patients expressing a single phenotype (whether Brugada syndrome or Long QT syndrome type 3). This trials is led on the impact on Risk Stratification of Overlap Syndrome Phenotype in Patients With E1784K Mutation in SCN5A ( RISKOVER )
The objectives of the study are to investigate if KCNQ1 mutation in Romano-Ward long QT patients can be associated with changes in insulin regulation and with psychological features of compulsivity, impulsivity and behavioural rigidity.
This research will determine if: 1) Oral progesterone attenuates drug-induced QT interval, J-Tpeak and Tpeak-Tend lengthening in postmenopausal women 50 years of age or older, and 2) Transdermal testosterone attenuates drug-induced QT interval, J-Tpeak and Tpeak-Tend lengthening in men 65 years of age or older. This investigation will consist of two concurrent prospective, randomized, double-blind, placebo-controlled crossover-design studies in a) Postmenopausal women, and b) Men 65 years of age or older. Study 1: Each postmenopausal woman will take progesterone or placebo capsules for 1 week. After a 14-day "washout" (no progesterone or placebo) each subject will then take the alternative therapy (progesterone or placebo) for 1 week. After 7 days of each treatment, subjects will present to the clinical research center to receive a small dose of the QT interval-lengthening drug ibutilide, and the effect on the QT, J-Tpeak and Tpeak-Tend intervals during the progesterone and placebo phases will be compared. Study 2: Each man 65 years of age or older will apply transdermal testosterone or transdermal placebo gel for 3 days. After a 7-day "washout" (no testosterone or placebo) each subject will then apply the alternative therapy (testosterone or placebo gel) for 1 week. After 3 days of each treatment, subjects will present to the clinical research center to receive a small dose of the QT interval-lengthening drug ibutilide, and the effect on the QT, J-Tpeak and Tpeak-Tend intervals during the testosterone and placebo phases will be compared.
Novel therapy for the Long QT Syndrome based on the mechanism of action of the disease-causing mutations Long QT syndrome type 2 (LQT2) accounts for ~ 35% of all LQTS cases and is difficult to manage, as beta-blockers frequently fail to provide full protection. Most LQT2 patients (pts) have a Class 2 mutation, which implies defective "trafficking". Lumacaftor (LUM) is a drug developed and currently indicated for the treatment of cystic fibrosis (CF) in patients homozygous for the F508del mutation in the CFTR gene. LUM corrects protein folding and trafficking defects of mutant and misfolded CFTR channels, restoring their cell surface expression. The investigators recently demonstrated that LUM can rescue in vitro the LQTS phenotype observed in human induced pluripotent stem cell- derived cardiomyocytes (hiPSC-CMs) from pts with LQT2 Class 2 mutations (PMID: 29020304) and in these same two patients Orkambi administrated for 7 days at the same dosage approved for cystic fibrosis showed to reduce their QTc (PMID: 30753398). With the present phase II clinical trial (MAST2) the investigators will enroll 20 LQT2 patients (see inclusion and exclusion criteria) and they will test in vivo the efficacy of Orkambi in shortening their QTc. Patients will be admitted to hospital for a maximum of 7 days (minimum in-hospital stay based on evidence of QTc shortening). Orkambi will be administered at the dose approved for cystic fibrosis and during the entire period continuous ECG monitoring through both telemetry and 12-lead 24-hr Holter monitoring will be performed and QTc length and morphology will be analyzed.
The purpose of this study is to validate the continuous patch monitoring system to evaluate cardiac arrhythmias in patients receiving drugs that can cause cardiac complications and compare the continuous patch system with standard electrocardiograms (ECGs).
The goal of this study is to determine whether anti-Ro/SSA antibodies are associated with acquired QT prolongation in subjects with connective tissue disease. The investigators will investigate whether gender or race influence correlation between anti-Ro antibody status and prolonged QT interval and the role of inflammatory cytokines in association with anti-Ro antibodies and QT prolongation. The investigators propose to add an additional objective to test whether QT prolongation is reversible with moderate doses of prednisone in patients with QT interval greater than 500 msec.