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Children (Basel, Switzerland) Apr 2024CACNA1C gene encodes the alpha 1 subunit of the CaV1.2 L-type Ca2+ channel. Pathogenic variants in this gene have been associated with cardiac rhythm disorders such as... (Review)
Review
CACNA1C gene encodes the alpha 1 subunit of the CaV1.2 L-type Ca2+ channel. Pathogenic variants in this gene have been associated with cardiac rhythm disorders such as long QT syndrome, Brugada syndrome and Timothy syndrome. Recent evidence has suggested the possible association between CACNA1C mutations and neurologically-isolated (in absence of cardiac involvement) phenotypes in children, giving birth to a wider spectrum of CACNA1C-related clinical presentations. However, to date, little is known about the variety of both neurological and non-neurological signs/symptoms in the neurologically-predominant phenotypes. We conducted a systematic review of neurologically-predominant presentations without cardiac conduction defects, associated with CACNA1C mutations. We also reported a novel de novo missense pathogenic variant in the CACNA1C gene of a children patient presenting with constructional, dressing and oro-buccal apraxia associated with behavioral abnormalities, mild intellectual disability, dental anomalies, gingival hyperplasia and mild musculoskeletal defects, without cardiac conduction defects. The present study highlights the importance of considering the investigation of the CACNA1C gene in children's neurological isolated syndromes, and expands the phenotype of the CACNA1C related conditions. In addition, the present study highlights that, even in absence of cardiac conduction defects, nuanced clinical manifestations of the Timothy syndrome (e.g., dental and gingival defects) could be found. These findings suggest the high variable expressivity of the CACNA1C gene and remark that the absence of cardiac involvement should not mislead the diagnosis of a CACNA1C related disorder.
PubMed: 38790536
DOI: 10.3390/children11050541 -
Clinical Lung Cancer Jun 2024A systematic literature review was conducted to determine the incidence and mortality of QT-interval prolongation (QTp), torsades de pointes (TdP), and heart failure... (Review)
Review
A systematic literature review was conducted to determine the incidence and mortality of QT-interval prolongation (QTp), torsades de pointes (TdP), and heart failure (HF) in patients with non-small cell lung cancer (NSCLC) who received epidermal growth factor receptor (EGFR) TKIs. Of 296 identified publications, 95 met eligibility criteria and were abstracted for QTp/TdP and HF outcomes (QTp/TdP: 83 publications, including 5 case study publications; HF: 79 publications, including 6 case study publications [involving 8 patients]). QTp incidence ranged from 0% to 27.8% in observational studies and from 0% to 11% in clinical trials, with no deaths due to QTp. There were no TdP events or deaths due to TdP. The incidence of HF ranged from 0% to 8%, and HF mortality rates ranged from 0% to 4%. Patients receiving treatment with EGFR TKIs should be monitored for signs of QTp, TdP, and HF per prescribing information. Standardized definitions and methods to improve monitoring of QTp, TdP, and HF-related events are needed in patients with NSCLC.
Topics: Humans; Carcinoma, Non-Small-Cell Lung; Heart Failure; Lung Neoplasms; ErbB Receptors; Torsades de Pointes; Protein Kinase Inhibitors; Long QT Syndrome; Incidence; Tyrosine Kinase Inhibitors
PubMed: 38553324
DOI: 10.1016/j.cllc.2024.02.005 -
The Cochrane Database of Systematic... Mar 2024Cardiovascular diseases (CVDs) are the leading cause of death globally, accounting for almost 18 million deaths annually. People with CVDs have a five times greater... (Review)
Review
BACKGROUND
Cardiovascular diseases (CVDs) are the leading cause of death globally, accounting for almost 18 million deaths annually. People with CVDs have a five times greater chance of suffering a recurrent cardiovascular event than people without known CVDs. Although drug interventions have been shown to be cost-effective in reducing the risk of recurrent cardiovascular events, adherence to medication remains suboptimal. As a scalable and cost-effective approach, mobile phone text messaging presents an opportunity to convey health information, deliver electronic reminders, and encourage behaviour change. However, it is uncertain whether text messaging can improve medication adherence and clinical outcomes. This is an update of a Cochrane review published in 2017.
OBJECTIVES
To evaluate the benefits and harms of mobile phone text messaging for improving medication adherence in people with CVDs compared to usual care.
SEARCH METHODS
We searched CENTRAL, MEDLINE, Embase, four other databases, and two trial registers. We also checked the reference lists of all primary included studies and relevant systematic reviews and meta-analyses. The date of the latest search was 30 August 2023.
SELECTION CRITERIA
We included randomised controlled trials (RCTs) with participants with established arterial occlusive events. We included trials investigating interventions using short message service (SMS) or multimedia messaging service (MMS) with the aim of improving adherence to medication for the secondary prevention of cardiovascular events. The comparator was usual care. We excluded cluster-RCTs and quasi-RCTs.
DATA COLLECTION AND ANALYSIS
We used standard Cochrane methods. Our primary outcomes were medication adherence, fatal cardiovascular events, non-fatal cardiovascular events, and combined CVD event. Secondary outcomes were low-density lipoprotein cholesterol for the effect of statins, blood pressure for antihypertensive drugs, heart rate for the effect of beta-blockers, urinary 11-dehydrothromboxane B2 for the antiplatelet effects of aspirin, adverse effects, and patient-reported experience. We used GRADE to assess the certainty of the evidence for each outcome.
MAIN RESULTS
We included 18 RCTs involving a total of 8136 participants with CVDs. We identified 11 new studies in the review update and seven studies in the previous version of the review. Participants had various CVDs including acute coronary syndrome, coronary heart disease, stroke, myocardial infarction, and angina. All studies were conducted in middle- and high-income countries, with no studies conducted in low-income countries. The mean age of participants was 53 to 64 years. Participants were recruited from hospitals or cardiac rehabilitation facilities. Follow-up ranged from one to 12 months. There was variation in the characteristics of text messages amongst studies (e.g. delivery method, frequency, theoretical grounding, content used, personalisation, and directionality). The content of text messages varied across studies, but generally included medication reminders and healthy lifestyle information such as diet, physical activity, and weight loss. Text messages offered advice, motivation, social support, and health education to promote behaviour changes and regular medication-taking. We assessed risk of bias for all studies as high, as all studies had at least one domain at unclear or high risk of bias. Medication adherence Due to different evaluation score systems and inconsistent definitions applied for the measurement of medication adherence, we did not conduct meta-analysis for medication adherence. Ten out of 18 studies showed a beneficial effect of mobile phone text messaging for medication adherence compared to usual care, whereas the other eight studies showed either a reduction or no difference in medication adherence with text messaging compared to usual care. Overall, the evidence is very uncertain about the effects of mobile phone text messaging for medication adherence when compared to usual care. Fatal cardiovascular events Text messaging may have little to no effect on fatal cardiovascular events compared to usual care (odds ratio 0.83, 95% confidence interval (CI) 0.47 to 1.45; 4 studies, 1654 participants; low-certainty evidence). Non-fatal cardiovascular events We found very low-certainty evidence that text messaging may have little to no effect on non-fatal cardiovascular events. Two studies reported non-fatal cardiovascular events, neither of which found evidence of a difference between groups. Combined CVD events We found very low-certainty evidence that text messaging may have little to no effect on combined CVD events. Only one study reported combined CVD events, and did not find evidence of a difference between groups. Low-density lipoprotein cholesterol Text messaging may have little to no effect on low-density lipoprotein cholesterol compared to usual care (mean difference (MD) -1.79 mg/dL, 95% CI -4.71 to 1.12; 8 studies, 4983 participants; very low-certainty evidence). Blood pressure Text messaging may have little to no effect on systolic blood pressure (MD -0.93 mmHg, 95% CI -3.55 to 1.69; 8 studies, 5173 participants; very low-certainty evidence) and diastolic blood pressure (MD -1.00 mmHg, 95% CI -2.49 to 0.50; 5 studies, 3137 participants; very low-certainty evidence) when compared to usual care. Heart rate Text messaging may have little to no effect on heart rate compared to usual care (MD -0.46 beats per minute, 95% CI -1.74 to 0.82; 4 studies, 2946 participants; very low-certainty evidence).
AUTHORS' CONCLUSIONS
Due to limited evidence, we are uncertain if text messaging reduces medication adherence, fatal and non-fatal cardiovascular events, and combined cardiovascular events in people with cardiovascular diseases when compared to usual care. Furthermore, text messaging may result in little or no effect on low-density lipoprotein cholesterol, blood pressure, and heart rate compared to usual care. The included studies were of low methodological quality, and no studies assessed the effects of text messaging in low-income countries or beyond the 12-month follow-up. Long-term and high-quality randomised trials are needed, particularly in low-income countries.
Topics: Humans; Middle Aged; Text Messaging; Cardiovascular Diseases; Secondary Prevention; Cell Phone; Cholesterol, LDL; Medication Adherence
PubMed: 38533994
DOI: 10.1002/14651858.CD011851.pub3 -
Journal of Arrhythmia Dec 2023Inherited Primary Arrhythmias Syndromes (IPAS), especially Brugada syndrome (BrS), have been associated with arrhythmogenic substrates that can be targeted through...
BACKGROUND
Inherited Primary Arrhythmias Syndromes (IPAS), especially Brugada syndrome (BrS), have been associated with arrhythmogenic substrates that can be targeted through ablation. This meta-analysis evaluated the outcomes of catheter ablation (CA) in different types of IPAS based on procedural guidance and location.
METHODS
A systematic search was conducted across multiple databases to identify studies reporting on ventricular arrhythmia (VA) events before and after CA in IPAS, including BrS, Long-QT syndrome (LQTS), Early repolarization syndrome (ERS), and Idiopathic ventricular fibrillation (IVF). The primary outcomes were VA recurrence and VA burden, evaluated through conditional subgroup analysis. Procedural data were collected as secondary outcomes.
RESULTS
A total of 21 studies involving 584 IPAS patients who underwent CA were included. Following a mean follow-up duration of 33.5 months, substrate-based ablation demonstrated efficacy in reducing VA recurrence across all types of IPAS [RR 0.23; 95% CI (0.13-0.39); < .001; = 74%]. However, activation guidance ablation was found to be effective only in IVF cases. Although recurrences still occurred, CA was successful in reducing VA burden [MD -4.70; 95% CI (-6.11-(-3.29); < .001; = 74%]. The mean size of arrhythmogenic substrate was 15.70 cm [95% CI (12.34-19.99 cm)], predominantly distributed in the epicardial right ventricular outflow tract (RVOT) in BrS cases and LQTS [Proportion 0.99; 95% CI (0.96-1.00) and Proportion 0.82; 95% CI ( 0.59-1.00), respectively].
CONCLUSION
Substrate-based CA has demonstrated effective prevention of VA and reduction in VA burden in IPAS cases.
PubMed: 38045449
DOI: 10.1002/joa3.12947 -
Clinical Cardiology Sep 2023Screening elite athletes for conditions associated with sudden cardiac death is recommended by numerous international guidelines. Current athlete electrocardiogram... (Review)
Review
Screening elite athletes for conditions associated with sudden cardiac death is recommended by numerous international guidelines. Current athlete electrocardiogram interpretation criteria recommend the Bazett formula (QTcB) for correcting QT interval. However, other formulae may perform better at lower and higher heart rates (HR). This review aimed to examine the literature on various QT correction methods in athletes and young people aged 14-35 years and determine the most accurate method of calculating QTc in this population. A systematic review of MEDLINE, EMBASE, Scopus, and SportDiscus was performed. Papers comparing at least two different methods of QT interval correction in athletes or young people were included. Quality and risk of bias were assessed using a standardized tool. The search strategy identified 545 papers, of which 10 met the criteria and were included. Nine of these studies concluded that QTcB was least reliable for removing the effect of HR and was inaccurate at both high (>90 beats per min [BPM]) and low (<60 BPM) HRs. No studies supported the use of QTcB in athletes and young people. Alternative QT correction algorithms such as Fridericia (QTcF) produce more accurate correction of QT interval at HRs seen in athletes and young people. QTcB is less accurate at lower and higher HRs. QTcF has been shown to be more accurate in these HR ranges and may be preferred to QTcB for QTc calculation in athletes and young people. However, accurate QTc reference values for discrete HRs using alternative algorithms are not well established and require further research.
Topics: Humans; Adolescent; Long QT Syndrome; Heart Rate; Death, Sudden, Cardiac; Athletes; Algorithms; Electrocardiography
PubMed: 37470093
DOI: 10.1002/clc.24093 -
Frontiers in Cardiovascular Medicine 2023To perform a meta-analysis to discover the performance of ML algorithms in identifying Congenital long QT syndrome (LQTS). (Review)
Review
INTRODUCTION
To perform a meta-analysis to discover the performance of ML algorithms in identifying Congenital long QT syndrome (LQTS).
METHODS
The searched databases included Cochrane, EMBASE, Web of Science, and PubMed. Our study considered all English-language studies that reported the detection of LQTS using ML algorithms. Quality was assessed using QUADAS-2 and QUADAS-AI tools. The bivariate mixed effects models were used in our study. Based on genotype data for LQTS, we performed a subgroup analysis.
RESULTS
Out of 536 studies, 8 met all inclusion criteria. The pooled area under the receiving operating curve (SAUROC) for detecting LQTS was 0.95 (95% CI: 0.31-1.00); sensitivity was 0.87 (95% CI: 0.83-0.90), and specificity was 0.91 (95% CI: 0.88-0.93). Additionally, diagnostic odd ratio (DOR) was 65 (95% CI: 39-109). The positive likelihood ratio (PLR) was 9.3 (95% CI: 7.0-12.3) and the negative likelihood ratio (NLR) was 0.14 (95% CI: 0.11-0.20), with very low heterogeneity (= 16%).
DISCUSSION
We found that machine learning can be used to detect features of rare cardiovascular disease like LQTS, thus increasing our understanding of intelligent interpretation of ECG. To improve ML performance in the classification of LQTS subtypes, further research is required.
SYSTEMATIC REVIEW REGISTRATION
identifier PROSPERO CRD42022360122.
PubMed: 37351282
DOI: 10.3389/fcvm.2023.1172451 -
Archives of Cardiovascular Diseases Feb 2023Conflicting findings have described the association between prolonged heart rate-corrected QT interval (QTc) and cardiovascular disease. (Meta-Analysis)
Meta-Analysis
BACKGROUND
Conflicting findings have described the association between prolonged heart rate-corrected QT interval (QTc) and cardiovascular disease.
AIMS
To identify articles investigating the association between QTc and cardiovascular disease morbidity and mortality, and to summarize the available evidence for the general and type 2 diabetes populations.
METHODS
A systematic search was performed in PubMed and Embase in May 2022 to identify studies that investigated the association between QTc prolongation and cardiovascular disease in both the general and type 2 diabetes populations. Screening, full-text assessment, data extraction and risk of bias assessment were performed independently by two reviewers. Effect estimates were pooled across studies using random-effect models.
RESULTS
Of the 59 studies included, 36 qualified for meta-analysis. Meta-analysis of the general population studies showed a significant association for: overall cardiovascular disease (fatal and non-fatal) (hazard ratio [HR] 1.68, 95% confidence interval [CI] 1.33-2.12; I=69%); coronary heart disease (fatal and non-fatal) in women (HR 1.27, 95% CI 1.08-1.50; I=38%; coronary heart disease (fatal and non-fatal) in men (HR 2.07, 95% CI 1.26-3.39; I=78%); stroke (HR 1.59, 95% CI 1.29-1.96; I=45%); sudden cardiac death (HR 1.60, 95% CI 1.14-2.25; I=68%); and atrial fibrillation (HR 1.55, 95% CI 1.31-1.83; I=0.0%). No significant association was found for cardiovascular disease in the type 2 diabetes population.
CONCLUSION
QTc prolongation was associated with risk of cardiovascular disease in the general population, but not in the type 2 diabetes population.
Topics: Male; Humans; Female; Cardiovascular Diseases; Risk Factors; Heart Rate; Diabetes Mellitus, Type 2; Long QT Syndrome; Atrial Fibrillation; Coronary Disease; Electrocardiography
PubMed: 36690508
DOI: 10.1016/j.acvd.2022.11.007 -
Frontiers in Cardiovascular Medicine 2022Mutations in the gene-encoding for the major Ca channel of the heart-may exhibit a variety of clinical manifestations. These include typical or atypical Timothy...
Geno- and phenotypic characteristics and clinical outcomes of gene mutation associated Timothy syndrome, "cardiac only" Timothy syndrome and isolated long QT syndrome 8: A systematic review.
BACKGROUND
Mutations in the gene-encoding for the major Ca channel of the heart-may exhibit a variety of clinical manifestations. These include typical or atypical Timothy syndromes (TS) which are associated with multiple organ manifestations, and cardiac involvement in form of malignant arrhythmias, QTc prolongation, or AV block. "Cardiac only" Timothy syndrome (COTS) shows no extracardiac manifestation, whereas some gene mutations are associated with QTc prolongation alone (isolated long QT syndrome 8, LQT8).
METHODS
A systematic search of the literature reporting cases of gene mutation associated syndromes, including TS, COTS and isolated LQT8 major databases published from 2004 through 2019 was performed. Detailed patient-level phenotypic and genotypic characteristics, as well as long-term outcome measures were collected and compared between pre-specified patient groups, defined both on phenotype and genotype.
RESULTS
A total of 59 TS, 6 COTS, and 20 isolated LQT8 index cases were identified. Apart of syndactyly or baldness, there were no major differences regarding clinical manifestations or outcome measures between TS subtypes, either defining TS subtypes on the genotype or based on the phenotype. Both subtypes were characterized by an extreme degree of QTc prolongation (median ≥600 ms) which were reflected in high major adverse cardiac event rate. On the other hand, there were marked differences between TS, COTS, and isolated LQT8. Timothy syndrome was characterized by a much earlier disease onset, much more pronounced QTc prolongation and much higher mortality rate than COTS or isolated LQT8. Similar differences were observed comparing exon 8/8A vs. non-exon 8/8A mutation carriers. TS showed a high degree of genetic homogeneity, as the p.Gly406Arg mutation either in exon 8 or exon 8A alone was responsible for 70% of the cases.
CONCLUSIONS
Clinical phenotypes associated with mutations in the gene show important clinical differences. Timothy syndrome is associated with the most severe clinical phenotype and with the highest risk of morbidity and mortality. However, distinguishing TS subtypes, in any form, are not supported by our data.
SYSTEMATIC REVIEW REGISTRATION
[https://www.crd.york.ac.uk/prospero/], identifier [CRD42020184737].
PubMed: 36523353
DOI: 10.3389/fcvm.2022.1021009 -
Annals of Noninvasive Electrocardiology... Jan 2023QTc prolongation is key in diagnosing long QT syndrome (LQTS), however 25%-50% with congenital LQTS (cLQTS) demonstrate a normal resting QTc. T wave morphology (TWM) can... (Review)
Review
INTRODUCTION
QTc prolongation is key in diagnosing long QT syndrome (LQTS), however 25%-50% with congenital LQTS (cLQTS) demonstrate a normal resting QTc. T wave morphology (TWM) can distinguish cLQTS subtypes but its role in acquired LQTS (aLQTS) is unclear.
METHODS
Electronic databases were searched using the terms "LQTS," "long QT syndrome," "QTc prolongation," "prolonged QT," and "T wave," "T wave morphology," "T wave pattern," "T wave biomarkers." Whole text articles assessing TWM, independent of QTc, were included.
RESULTS
Seventeen studies met criteria. TWM measurements included T-wave amplitude, duration, magnitude, Tpeak-Tend, QTpeak, left and right slope, center of gravity (COG), sigmoidal and polynomial classifiers, repolarizing integral, morphology combination score (MCS) and principal component analysis (PCA); and vectorcardiographic biomarkers. cLQTS were distinguished from controls by sigmoidal and polynomial classifiers, MCS, QTpeak, Tpeak-Tend, left slope; and COG x axis. MCS detected aLQTS more significantly than QTc. Flatness, asymmetry and notching, J-Tpeak; and Tpeak-Tend correlated with QTc in aLQTS. Multichannel block in aLQTS was identified by early repolarization (ERD ) and late repolarization (LRD ), with ERD reflecting hERG-specific blockade. Cardiac events were predicted in cLQTS by T wave flatness, notching, and inversion in leads II and V , left slope in lead V ; and COG last 25% in lead I. T wave right slope in lead I and T-roundness achieved this in aLQTS.
CONCLUSION
Numerous TWM biomarkers which supplement QTc assessment were identified. Their diagnostic capabilities include differentiation of genotypes, identification of concealed LQTS, differentiating aLQTS from cLQTS; and determining multichannel versus hERG channel blockade.
Topics: Humans; Electrocardiography; Long QT Syndrome; Genotype; Biomarkers
PubMed: 36345173
DOI: 10.1111/anec.13015 -
Cureus Aug 2022Torsades de Pointes (TdP) is a rare form of tachyarrhythmia which can potentially be fatal due to its tendency to degenerate into ventricular fibrillation. It is... (Review)
Review
Torsades de Pointes (TdP) is a rare form of tachyarrhythmia which can potentially be fatal due to its tendency to degenerate into ventricular fibrillation. It is described as a polymorphic ventricular tachycardia characterized by twisting of the QRS complexes around the electrocardiogram (ECG) baseline in patients with a prolonged QT interval. Prolonged QT interval is known as long QT syndrome. Torsades de Poccurs most commonly in patients with an extended QT interval duration, and even though monitoring an ECG can assist in its prevention, there is no defined duration of a QT interval that can lead to an increased risk of Torsades de Pointes. So, it is hard to determine what QT interval constitutes enough risk for Torsades de Pointes to require intervention. The QT interval duration also depends on other factors, namely heart rate (HR) and other factors such as drugs, congenital diseases, and a combination of both. In this study, we considered various causes of QT prolongation but mainly focused on congenital diseases, drugs, or perioperative risk of QT prolongation and the correlation with the risk of impending TdP. By following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and researching studies on various databases, namely PubMed, Science Direct, Medline, and CiNii we were able to find various systematic reviews and articles showing the association between prolonged QT interval and its degeneration into TdP. This review encourages further research into this topic to understand the implications of QT prolongation and how it can help save the lives of patients with known long QT syndrome, or those on QT prolonging drugs with simple ECG monitoring and treatment for the respective cause.
PubMed: 36110477
DOI: 10.7759/cureus.27833