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Ferreira AC, Dias‐Filho CAA, Jesus Silva Soares Junior N, Dias CJ, Monteiro SCM, Andrade RM, Mostarda CT. Phenotypes of mutations related to voltage‐dependent sodium channels on children and adolescents. J Biochem Mol Toxicol 2022; 36:e22993. [DOI: 10.1002/jbt.22993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 11/30/2021] [Accepted: 01/04/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Andressa Coelho Ferreira
- Laboratory of Cardiovascular Adaptations to Exercise—LACORE, Physical Education Department University Federal of Maranhão São Luís Brazil
| | - Carlos Alberto Alves Dias‐Filho
- Laboratory of Cardiovascular Adaptations to Exercise—LACORE, Physical Education Department University Federal of Maranhão São Luís Brazil
| | - Nivaldo Jesus Silva Soares Junior
- Laboratory of Cardiovascular Adaptations to Exercise—LACORE, Physical Education Department University Federal of Maranhão São Luís Brazil
| | - Carlos José Dias
- Laboratory of Cardiovascular Adaptations to Exercise—LACORE, Physical Education Department University Federal of Maranhão São Luís Brazil
- Physical Education Department UFMA Sao Luis Brazil
| | - Sally Cristina Moutinho Monteiro
- Laboratory of Cardiovascular Adaptations to Exercise—LACORE, Physical Education Department University Federal of Maranhão São Luís Brazil
- Pharmacy Department UFMA Sao Luis Brazil
| | - Rafael Martins Andrade
- Laboratory of Cardiovascular Adaptations to Exercise—LACORE, Physical Education Department University Federal of Maranhão São Luís Brazil
| | - Cristiano Teixeira Mostarda
- Laboratory of Cardiovascular Adaptations to Exercise—LACORE, Physical Education Department University Federal of Maranhão São Luís Brazil
- Pharmacy Department UFMA Sao Luis Brazil
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Martínez-Barrios E, Cesar S, Cruzalegui J, Hernandez C, Arbelo E, Fiol V, Brugada J, Brugada R, Campuzano O, Sarquella-Brugada G. Clinical Genetics of Inherited Arrhythmogenic Disease in the Pediatric Population. Biomedicines 2022; 10:106. [PMID: 35052786 PMCID: PMC8773373 DOI: 10.3390/biomedicines10010106] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 12/27/2021] [Accepted: 12/31/2021] [Indexed: 12/19/2022] Open
Abstract
Sudden death is a rare event in the pediatric population but with a social shock due to its presentation as the first symptom in previously healthy children. Comprehensive autopsy in pediatric cases identify an inconclusive cause in 40-50% of cases. In such cases, a diagnosis of sudden arrhythmic death syndrome is suggested as the main potential cause of death. Molecular autopsy identifies nearly 30% of cases under 16 years of age carrying a pathogenic/potentially pathogenic alteration in genes associated with any inherited arrhythmogenic disease. In the last few years, despite the increasing rate of post-mortem genetic diagnosis, many families still remain without a conclusive genetic cause of the unexpected death. Current challenges in genetic diagnosis are the establishment of a correct genotype-phenotype association between genes and inherited arrhythmogenic disease, as well as the classification of variants of uncertain significance. In this review, we provide an update on the state of the art in the genetic diagnosis of inherited arrhythmogenic disease in the pediatric population. We focus on emerging publications on gene curation for genotype-phenotype associations, cases of genetic overlap and advances in the classification of variants of uncertain significance. Our goal is to facilitate the translation of genetic diagnosis to the clinical area, helping risk stratification, treatment and the genetic counselling of families.
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Affiliation(s)
- Estefanía Martínez-Barrios
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
| | - Sergi Cesar
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
| | - José Cruzalegui
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
| | - Clara Hernandez
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
| | - Elena Arbelo
- Centro de Investigación Biomédica en Red, Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (E.A.); (R.B.)
- Arrhythmias Unit, Hospital Clinic, University of Barcelona-IDIBAPS, 08036 Barcelona, Spain
| | - Victoria Fiol
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
| | - Josep Brugada
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
- Centro de Investigación Biomédica en Red, Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (E.A.); (R.B.)
- Arrhythmias Unit, Hospital Clinic, University of Barcelona-IDIBAPS, 08036 Barcelona, Spain
| | - Ramon Brugada
- Centro de Investigación Biomédica en Red, Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (E.A.); (R.B.)
- Medical Science Department, School of Medicine, University of Girona, 17004 Girona, Spain
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Girona, Spain
- Cardiology Service, Hospital Josep Trueta, University of Girona, 17007 Girona, Spain
| | - Oscar Campuzano
- Centro de Investigación Biomédica en Red, Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (E.A.); (R.B.)
- Medical Science Department, School of Medicine, University of Girona, 17004 Girona, Spain
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Girona, Spain
| | - Georgia Sarquella-Brugada
- Arrhythmias Unit, Hospital Sant Joan de Déu, University of Barcelona, 08007 Barcelona, Spain; (E.M.-B.); (S.C.); (J.C.); (C.H.); (V.F.); (J.B.)
- Medical Science Department, School of Medicine, University of Girona, 17004 Girona, Spain
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3
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Környei L, Szabó A, Róth G, Kardos A, Fogarasi A. Frequency of syncope as a presenting symptom in channelopathies diagnosed in childhood. Can the multivariable EGSYS score unmask these children? Eur J Pediatr 2021; 180:1553-1559. [PMID: 33447893 DOI: 10.1007/s00431-020-03913-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 12/13/2020] [Accepted: 12/16/2020] [Indexed: 11/24/2022]
Abstract
Pediatric syncope raises cardiac etiology concern as it might be the first sign of life-threatening arrhythmia syndromes. Our aim was to study the incidence of syncope as the presenting symptom in children with arrhythmia syndromes, and if known, warning signs are helpful to reveal the arrhythmic origin. All data on children with channelopathy was followed by a tertiary pediatric cardiac center between 2000 and 2018 and data were reviewed retrospectively. Forty-eight patients were enrolled, representing long QT syndrome (n = 39), catecholaminergic polymorphic ventricular tachycardia (n = 5), and Brugada syndrome (n = 4). Presenting symptoms were syncope in 13 cases [27%] (including 7 initially mislabeled as epilepsy) and sudden cardiac arrest (SCA) in 9 cases [19%]. In the rest of the group, the concern for arrhythmic etiology was raised by either an abnormal ECG during sports medicine screening (n = 13) [27%] or a positive family history of channelopathy (n = 13) [27%]. None of the patients presenting with SCA had a prior syncopal history. Six patients presenting with syncope and afterward treated with ICD had an appropriate shock. Description of witnessed syncope was available in eight out of thirteen children presenting with syncope. Multivariable EGSYS score suggested cardiac origin (≥ 3 points) in 7 out of 8 (88%) patients.Conclusions: Syncope was a relatively uncommon presenting symptom of channelopathies in this sample and did not always precede sudden cardiac arrests. However, we found that multivariable EGSYS score can identify syncope of arrhythmic origin, raising suspicion for pediatric channelopathies even in patients previously misdiagnosed with epilepsy. What is known: • Cardiac syncope is rare in children but can be the first sign of a potentially fatal primary arrhythmia syndrome and is frequently misdiagnosed as atypical/therapy-resistant epilepsy. • Multivariate EGSYS score is effective to diagnose cardiac syncope in adults. What is new: • Cardiac syncope as a presenting symptom is not common in children with cardiac channelopathies and is not often present before sudden cardiac arrest. • Multivariable EGSYS score might identify cardiac syncope in children with a hereditary and secondary channelopathy.
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Affiliation(s)
- László Környei
- Gottsegen György Hungarian Institute of Cardiology, Pediatric Heart Center, Haller u. 29, Budapest, 1096, Hungary.
| | - Andrea Szabó
- Gottsegen György Hungarian Institute of Cardiology, Pediatric Heart Center, Haller u. 29, Budapest, 1096, Hungary
| | - György Róth
- Gottsegen György Hungarian Institute of Cardiology, Pediatric Heart Center, Haller u. 29, Budapest, 1096, Hungary
| | - Attila Kardos
- Gottsegen György Hungarian Institute of Cardiology, Budapest, Hungary
| | - András Fogarasi
- Department of Neurology, Bethesda Children's Hospital, Budapest, Hungary
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Ohno S, Ozawa J, Fukuyama M, Makiyama T, Horie M. An NGS-based genotyping in LQTS; minor genes are no longer minor. J Hum Genet 2020; 65:1083-1091. [PMID: 32681117 DOI: 10.1038/s10038-020-0805-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 06/15/2020] [Accepted: 07/07/2020] [Indexed: 11/09/2022]
Abstract
Mutations in KCNQ1, KCNH2, and SCN5A are the major cause of long QT syndrome (LQTS). More than 90% of the genotyped patients have been reported to carry mutations in any of these three genes. Thanks to increasing popularity of next generation sequencer (NGS), novel CACNA1C mutations have been identified among LQTS patients without extra-cardiac phenotypes. We aimed to clarify the frequency of genotypes in LQTS patients in the era of NGS. The study comprised 160 congenital LQTS patients (71 males) registered from November 2015 to September 2018. Inclusion criteria was QTc > 460 ms and Schwartz score ≥ 3. We performed genetic analysis using target gene method by NGS and confirmed the mutations by Sanger method. The median age for genetic screening was 13 (0-68) years. Sixteen patients suffered cardiac arrest, 47 syncope, and 97 were asymptomatic. We identified genetic mutations in 111 (69.4%) patients including 6 CACNA1C (5.4% of the genotyped patients) with 4 asymptomatic patients. Five (3.1%) patients carried double mutations; three out of them with RYR2 and KCNQ1 or KCNH2. In conclusion, CACNA1C screening would be recommended even if the patient is asymptomatic to elucidate the genetic background of the LQTS patients.
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Affiliation(s)
- Seiko Ohno
- Department of Bioscience and Genetics, National Cerebral and Cardiovascular Center, Suita, Japan. .,Center for Epidemiologic Research in Asia, Shiga University of Medical Science, Otsu, Japan. .,Department of Cardiovascular Medicine, Shiga University of Medical Science, Otsu, Japan.
| | - Junichi Ozawa
- Department of Pediatrics, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Megumi Fukuyama
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Otsu, Japan
| | - Takeru Makiyama
- Department of Cardiovascular Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Minoru Horie
- Center for Epidemiologic Research in Asia, Shiga University of Medical Science, Otsu, Japan.,Department of Cardiovascular Medicine, Shiga University of Medical Science, Otsu, Japan
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Shaboodien G, Spracklen TF, Kamuli S, Ndibangwi P, Van Niekerk C, Ntusi NAB. Genetics of inherited cardiomyopathies in Africa. Cardiovasc Diagn Ther 2020; 10:262-278. [PMID: 32420109 DOI: 10.21037/cdt.2019.10.03] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In sub-Saharan Africa (SSA), the burden of noncommunicable diseases (NCDs) is rising disproportionately in comparison to the rest of the world, affecting urban, semi-urban and rural dwellers alike. NCDs are predicted to surpass infections like human immunodeficiency virus, tuberculosis and malaria as the leading cause of mortality in SSA over the next decade. Heart failure (HF) is the dominant form of cardiovascular disease (CVD), and a leading cause of NCD in SSA. The main causes of HF in SSA are hypertension, cardiomyopathies, rheumatic heart disease, pericardial disease, and to a lesser extent, coronary heart disease. Of these, the cardiomyopathies deserve greater attention because of the relatively poor understanding of mechanisms of disease, poor outcomes and the disproportionate impact they have on young, economically active individuals. Morphofunctionally, cardiomyopathies are classified as dilated, hypertrophic, restrictive and arrhythmogenic; regardless of classification, at least half of these are inherited forms of CVD. In this review, we summarise all studies that have investigated the incidence of cardiomyopathy across Africa, with a focus on the inherited cardiomyopathies. We also review data on the molecular genetic underpinnings of cardiomyopathy in Africa, where there is a striking lack of studies reporting on the genetics of cardiomyopathy. We highlight the impact that genetic testing, through candidate gene screening, association studies and next generation sequencing technologies such as whole exome sequencing and targeted resequencing has had on the understanding of cardiomyopathy in Africa. Finally, we emphasise the need for future studies to fill large gaps in our knowledge in relation to the genetics of inherited cardiomyopathies in Africa.
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Affiliation(s)
- Gasnat Shaboodien
- Cardiovascular Genetics Laboratory, Hatter Institute for Cardiovascular Research in Africa, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Timothy F Spracklen
- Cardiovascular Genetics Laboratory, Hatter Institute for Cardiovascular Research in Africa, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Stephen Kamuli
- Cardiovascular Genetics Laboratory, Hatter Institute for Cardiovascular Research in Africa, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Polycarp Ndibangwi
- Cardiovascular Genetics Laboratory, Hatter Institute for Cardiovascular Research in Africa, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Carla Van Niekerk
- Cardiovascular Genetics Laboratory, Hatter Institute for Cardiovascular Research in Africa, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Ntobeko A B Ntusi
- Cardiovascular Genetics Laboratory, Hatter Institute for Cardiovascular Research in Africa, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.,Cape Universities Body Imaging Centre, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
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6
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Isbister J, Semsarian C. Sudden cardiac death: an update. Intern Med J 2020; 49:826-833. [PMID: 31295785 DOI: 10.1111/imj.14359] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2019] [Revised: 04/11/2019] [Accepted: 04/16/2019] [Indexed: 01/15/2023]
Abstract
Sudden cardiac death (SCD) is a devastating and all too common result of both acquired and genetic heart diseases. The profound sadness endured by families is compounded by the risk many of these deaths confer upon surviving relatives. For those with known cardiac disease, disease-specific therapy and risk stratification are key to reducing sudden death. For families of a SCD victim, uncovering a definitive cause of death can help relieve the agonising uncertainty and is a vital first step in screening surviving relatives and instituting therapy to reduce SCD risk. Increasing knowledge about the molecular mechanisms and genetic drivers of malignant arrhythmias in the diverse clinical entities that can cause SCD is vital if we are to optimise risk stratification and personalise patient care. Advances in diagnostic tools, disease-specific therapy and defibrillator technology are improving outcomes for patients and their families but there is still much progress to be made.
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Affiliation(s)
- Julia Isbister
- Agnes Ginges Centre for Molecular Cardiology at Centenary Institute, The University of Sydney, Sydney, New South Wales, Australia.,Faculty of Medicine and Heath, The University of Sydney, Sydney, New South Wales, Australia
| | - Christopher Semsarian
- Agnes Ginges Centre for Molecular Cardiology at Centenary Institute, The University of Sydney, Sydney, New South Wales, Australia.,Faculty of Medicine and Heath, The University of Sydney, Sydney, New South Wales, Australia.,Department of Cardiology, Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
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7
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Oliveira ACG, Neves ILI, Sacilotto L, Olivetti NQS, Santos-Paul MAD, Montano TCP, Carvalho CMA, Wu TC, Grupi CJ, Barbosa SA, Pastore CA, Samesima N, Hachul DT, Scanavacca MI, Neves RS, Darrieux FCC. Is It Safe for Patients With Cardiac Channelopathies to Undergo Routine Dental Care? Experience From a Single-Center Study. J Am Heart Assoc 2019; 8:e012361. [PMID: 31319747 PMCID: PMC6761655 DOI: 10.1161/jaha.119.012361] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Background Brugada syndrome and long-QT syndrome may account for at least one third of unexplained sudden cardiac deaths. Dental care in patients with cardiac channelopathies is challenging because of the potential risk of life-threatening events. We hypothesized that the use of local dental anesthesia with lidocaine with and without epinephrine is safe and does not result in life-threatening arrhythmias in patients with channelopathies. Methods and Results We performed a randomized, double-blind pilot trial comparing the use of 2% lidocaine without a vasoconstrictor and with 1:100 000 epinephrine in 2 sessions of restorative dental treatment with a washout period of 7 days (crossover trial). Twenty-eight-hour Holter monitoring was performed, and 12-lead electrocardiography, digital sphygmomanometry, and anxiety scale assessments were also conducted at 3 time points. Fifty-six dental procedures were performed in 28 patients (18 women, 10 men) with cardiac channelopathies: 16 (57.1%) had long-QT syndrome, and 12 (42.9%) had Brugada syndrome; 11 (39.3%) of patients had an implantable defibrillator. The mean age was 45.9±15.9 years. The maximum heart rate increased after the use of epinephrine during the anesthesia period from 82.1 to 85.8 beats per minute (P=0.008). In patients with long-QT syndrome, the median corrected QT was higher, from 450.1 to 465.4 ms (P=0.009) at the end of anesthesia in patients in whom epinephrine was used. The other measurements showed no statistically significant differences. No life-threatening arrhythmias occurred during dental treatment. Conclusions The use of local dental anesthesia with lidocaine, regardless of the use of a vasoconstrictor, did not result in life-threatening arrhythmias and appears to be safe in stable patients with cardiac channelopathies. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT03182777.
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Affiliation(s)
- Ana Carolina Guimarães Oliveira
- Unidade de Odontologia Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Itamara Lucia Itagiba Neves
- Unidade de Odontologia Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Luciana Sacilotto
- Nucleo Clinico-Cirurgico de Arritmias Cardiacas Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Natália Quintella Sangiorgi Olivetti
- Nucleo Clinico-Cirurgico de Arritmias Cardiacas Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Marcela Alves Dos Santos-Paul
- Unidade de Odontologia Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Tânia Cristina Pedroso Montano
- Unidade de Odontologia Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Cíntia Maria Alencar Carvalho
- Unidade de Odontologia Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Tan Chen Wu
- Nucleo Clinico-Cirurgico de Arritmias Cardiacas Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Cesar José Grupi
- Unidade de Eletrocardiografia Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Sílvio Alves Barbosa
- Unidade de Eletrocardiografia Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Carlos Alberto Pastore
- Unidade de Eletrocardiografia Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Nelson Samesima
- Unidade de Eletrocardiografia Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Denise Tessariol Hachul
- Nucleo Clinico-Cirurgico de Arritmias Cardiacas Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Maurício Ibrahim Scanavacca
- Nucleo Clinico-Cirurgico de Arritmias Cardiacas Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Ricardo Simões Neves
- Unidade de Odontologia Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
| | - Francisco Carlos Costa Darrieux
- Nucleo Clinico-Cirurgico de Arritmias Cardiacas Instituto do Coracao Hospital das Clinicas HCFMUSP Faculdade de Medicina Universidade de São Paulo Brazil
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8
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Elias Neto J, Tonet J, Frank R, Fontaine G. Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia (ARVC/D) - What We Have Learned after 40 Years of the Diagnosis of This Clinical Entity. Arq Bras Cardiol 2019; 112:91-103. [PMID: 30673021 PMCID: PMC6317628 DOI: 10.5935/abc.20180266] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 09/12/2018] [Indexed: 11/22/2022] Open
Abstract
Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) was initially
recognized as a clinical entity by Fontaine and Marcus, who evaluated a group of
patients with ventricular tachyarrhythmia from a structurally impaired right
ventricle (RV). Since then, there have been significant advances in the
understanding of the pathophysiology, manifestation and clinical progression,
and prognosis of the pathology. The identification of genetic mutations
impairing cardiac desmosomes led to the inclusion of this entity in the
classification of cardiomyopathies. Classically, ARVC/D is an inherited disease
characterized by ventricular arrhythmias, right and / or left ventricular
dysfunction; and fibro-fatty substitution of cardiomyocytes; its identification
can often be challenging, due to heterogeneous clinical presentation, highly
variable intra- and inter-family expressiveness, and incomplete penetrance. In the absence of a gold standard that allows the diagnosis of ARVC/D, several
diagnostic categories were combined and recently reviewed for a higher
diagnostic sensitivity, without compromising the specificity. The finding that
electrical abnormalities, particularly ventricular arrhythmias, usually precede
structural abnormalities is extremely important for risk stratification in
positive genetic members. Among the complementary exams, cardiac magnetic
resonance imaging (CMR) allows the early diagnosis of left ventricular
impairment, even before morpho-functional abnormalities. Risk stratification
remains a major clinical challenge, and antiarrhythmic drugs, catheter ablation
and implantable cardioverter defibrillator are the currently available
therapeutic tools. The disqualification of the sport prevents cases of sudden
death because the effort can trigger not only the electrical instability, but
also the onset and progression of the disease.
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Affiliation(s)
- Jorge Elias Neto
- Vitória Apart Hospital - Serviço de Eletrofisiologia, Serra, ES - Brazil
| | - Joelci Tonet
- 'Unité de Rythmologie de l'Institut de Cardiologie de l'Hôpital Pitié-Salpêtrière, Paris - France
| | - Robert Frank
- 'Unité de Rythmologie de l'Institut de Cardiologie de l'Hôpital Pitié-Salpêtrière, Paris - France
| | - Guy Fontaine
- 'Unité de Rythmologie de l'Institut de Cardiologie de l'Hôpital Pitié-Salpêtrière, Paris - France
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Abstract
Dear Editor Next generation sequencing (NGS) has changed the way we approach the diagnosis, prognosis and treatment of genetic disorders. It gave us base pair (bp) precision, multi-gene approach that can be executed in a timely and cost-effective manner. Despite some minor technical issues in NGS, it comes with great advantages. However, the clinical, and especially, genetic counseling profession will need to rise to the challenge to face some of the new issues, dilemmas and problems this new technology is bringing to the table. Some of the counseling guidelines predate the NGS era and will urgently need to be brought up to par with the technology.
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10
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Girolami F, Frisso G, Benelli M, Crotti L, Iascone M, Mango R, Mazzaccara C, Pilichou K, Arbustini E, Tomberli B, Limongelli G, Basso C, Olivotto I. Contemporary genetic testing in inherited cardiac disease: tools, ethical issues, and clinical applications. J Cardiovasc Med (Hagerstown) 2018; 19:1-11. [PMID: 29176389 PMCID: PMC5732648 DOI: 10.2459/jcm.0000000000000589] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Inherited cardiac diseases comprise a wide and heterogeneous spectrum of diseases of the heart, including the cardiomyopathies and the arrhythmic diseases in structurally normal hearts, that is, channelopathies. With a combined estimated prevalence of 3% in the general population, these conditions represent a relevant epidemiological entity worldwide, and are a major cause of cardiac morbidity and mortality in the young. The extraordinary progress achieved in molecular genetics over the last three decades has unveiled the complex molecular basis of many familial cardiac conditions, paving the way for routine use of gene testing in clinical practice. In current practice, genetic testing can be used in a clinically affected patient to confirm diagnosis, or to formulate a differential diagnosis among overlapping phenotypes or between hereditary and acquired (nongenetic) forms of disease. Although genotype–phenotype correlations are generally unpredictable, a precise molecular diagnosis can help predict prognosis in specific patient subsets and may guide management. In clinically unaffected relatives, genetic cascade testing is recommended, after the initial identification of a pathogenic variation, with the aim of identifying asymptomatic relatives who might be at risk of disease-related complications, including unexpected sudden cardiac death. Future implications include the identification of novel therapeutic targets and development of tailored treatments including gene therapy. This document reflects the multidisciplinary, ‘real-world’ experience required when implementing genetic testing in cardiomyopathies and arrhythmic syndromes, along the recommendations of various guidelines.
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Affiliation(s)
- Francesca Girolami
- Genetic Diagnostic Unit, Cardiomyopathies Unit, Careggi University Hospital, Florence
| | - Giulia Frisso
- Department Molecular Medicine and Medical Biotechnologies, University Federico II, Naples & CEINGE-Advanced Biotechnologies, Naples, Italy
| | - Matteo Benelli
- Bioinformatics Unit, Istituto Toscano Tumori, Hospital of Prato, Prato
| | - Lia Crotti
- Department of Cardiovascular, Neural and Metabolic Sciences, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, San Luca Hospital, Milan
| | - Maria Iascone
- USSD Laboratorio Genetica Medica, ASST Papa Giovanni XXIII, Bergamo
| | - Ruggiero Mango
- Division of Cardiology, Department of Emergency Medicine, Tor Vergata University of Rome, Rome
| | - Cristina Mazzaccara
- Department Molecular Medicine and Medical Biotechnologies, University Federico II, Naples & CEINGE-Advanced Biotechnologies, Naples, Italy
| | - Kalliope Pilichou
- Cardiovascular Pathology Unit, Department of Cardiac, Thoracic and Vascular Sciences, University of Padua, Padua
| | - Eloisa Arbustini
- Centre for Inherited Cardiovascular Diseases, IRCCS Foundation Policlinico San Matteo, Pavia
| | | | - Giuseppe Limongelli
- Department of Cardiothoracic Sciences, Campania University Luigi Vanvitelli, Caserta, Italy
| | - Cristina Basso
- Cardiovascular Pathology Unit, Department of Cardiac, Thoracic and Vascular Sciences, University of Padua, Padua
| | - Iacopo Olivotto
- Cardiomyopathies Unit, Careggi University Hospital, Florence
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12
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Abstract
BACKGROUND SCN5A encodes sodium-channel α-subunit Nav1.5. The mutations of SCN5A can lead to hereditary cardiac arrhythmias such as the long-QT syndrome type 3 and Brugada syndrome. Here we sought to identify novel mutations in a family with arrhythmia. METHODS Genomic DNA was isolated from blood of the proband, who was diagnosed with atrial flutter. Illumina Hiseq 2000 whole-exome sequencing was performed and an arrhythmia-related gene-filtering strategy was used to analyse the pathogenic genes. Sanger sequencing was applied to verify the mutation co-segregated in the family.Results and conclusionsA novel missense mutation in SCN5A (C335R) was identified, and this mutation co-segregated within the affected family members. This missense mutation was predicted to result in amplitude reduction in peak Na+ current, further leading to channel protein dysfunction. Our study expands the spectrum of SCN5A mutations and contributes to genetic counselling of families with arrhythmia.
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13
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Zhu YB, Luo JW, Jiang F, Liu G. Genetic analysis of sick sinus syndrome in a family harboring compound CACNA1C and TTN mutations. Mol Med Rep 2018; 17:7073-7080. [PMID: 29568937 PMCID: PMC5928663 DOI: 10.3892/mmr.2018.8773] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Accepted: 03/06/2018] [Indexed: 12/23/2022] Open
Abstract
Sick sinus syndrome (SSS) is a sinus node dysfunction characterized by severe sinus bradycardia. SSS results in insufficient blood supply to the brain, heart, kidneys, and other organs and is associated with the increased risk of sudden cardiac death. Bradyarrhythmia appears in the absence of any associated cardiac pathology and displays a genetic legacy. The present study identified a family with primary manifestation of sinus bradycardia (five individuals) along with early repolarization (four individuals) and atrial fibrillation (one individual). Targeted exome sequencing was used to screen exons and adjacent splice sites of 61 inherited arrhythmia‑associated genes, to detect pathogenic genes and variant sites in the proband. Family members were sequenced by Sanger sequencing and protein functions predicted by Polyphen‑2 software. A total of three rare variants were identified in the family, including two missense variants in calcium voltage‑gated channel subunit alpha1 C (CACNA1C) (gi:193788541, NM_001129843), c.1786G>A (p.V596M) and c.5344G>A (p.A1782T), and one missense variant in titin (TTN) c.49415G>A (p.R16472H) (gi:291045222, NM_003319). The variants p.V596M and p.R16472H were predicted to be deleterious and resulted in alterations in the amino acid type and sequence of the polypeptide chain, which may partially or completely inactivate the encoded protein. The comparison of literature, gene database, and pedigree phenotype analysis suggests that p.V596M or p.R16472H variants are pathogenic. The complex overlapping variants at three loci lead to a more severe phenotype in the proband, and may increase the susceptibility of individuals to atrial fibrillation. The simultaneous occurrence of V596M and R16472H may increase the severity of early repolarization. Various family members may have carried heterozygous mutants of p.A1782T and p.R16472H due to genetic heterogeneity, however did not exhibit clinical signs of cardiac electrophysiological alterations, potentially attributable to the low vagal tone. To the best of the author's knowledge, this is the first study to suggest the involvement of the novel missense CACNA1C c.1786G>A and TTN c.49415G>A variants in the inheritance of symptomatic bradycardia and development of SSS.
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Affiliation(s)
- Yao-Bin Zhu
- Department of Traditional Chinese Medicine, The First Affiliated Hospital, Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Jie-Wei Luo
- Provincial Clinical Medical College, Fujian Medical University, Fuzhou, Fujian 350001, P.R. China
| | - Fen Jiang
- Pharmacogenomics Research Center, Inje University College of Medicine, Busan 614‑715, Republic of Korea
| | - Gui Liu
- Department of Traditional Chinese Medicine, Fujian Provincial Hospital, Fuzhou, Fujian 350001, P.R. China
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14
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Abstract
INTRODUCTION AND OBJECTIVES The importance of sodium channels for the normal electrical activity of the heart is emphasized by the fact that mutations (inherited or de novo) in genes that encode for these channels or their associated proteins cause arrhythmogenic syndromes such as the Brugada syndrome and the long QT syndrome (LQTS). The aim of this study is to conduct a review of the literature on the mutations in the sodium channel complex responsible for heart disease and the implications of a close relationship between genetics and the clinical aspects of the main cardiac channelopathies, namely at the level of diagnosis, risk stratification, prognosis, screening of family members and treatment. METHODS The online Pubmed® database was used to search for articles published in this field in indexed journals. The MeSH database was used to define the following query: "Mutation [Mesh] AND Sodium Channels [Mesh] AND Heart Diseases [Mesh]", and articles published in the last 15 years, written in English or Portuguese and referring to research in human beings were included. CONCLUSIONS In the past few years, significant advances have been made to clarify the genetic and molecular basis of these syndromes. A greater understanding of the underlying pathophysiological mechanisms showed the importance of the relationship between genotype and phenotype and led to progress in the clinical approach to these patients. However, it is still necessary to improve diagnostic capacity, optimize risk stratification, and develop new specific treatments according to the genotype-phenotype binomial.
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15
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Fonseca DJ, Vaz da Silva MJ. Cardiac channelopathies: The role of sodium channel mutations. REVISTA PORTUGUESA DE CARDIOLOGIA (ENGLISH EDITION) 2018. [DOI: 10.1016/j.repce.2017.11.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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16
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Goldstein SA, Ward CC, Al-Khatib SM. The Use of Implantable Cardioverter-defibrillators in the Prevention of Sudden Cardiac Death: A Focus on Congenital Heart Disease and Inherited Arrhythmia Syndromes. J Innov Card Rhythm Manag 2018; 9:2996-3005. [PMID: 32494470 PMCID: PMC7252881 DOI: 10.19102/icrm.2018.090103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Accepted: 08/23/2017] [Indexed: 12/18/2022] Open
Abstract
Some congenital heart diseases (CHDs) and inherited arrhythmia syndromes are associated with an increased risk of sudden cardiac death (SCD). Appropriate selection criteria for implantable cardioverter-defibrillator (ICD) implantation in these patients are poorly defined due to a paucity of data available from randomized clinical trials, leading to current guidelines relying more on non-randomized studies and expert opinions to make their recommendations. This review describes available evidence-based risk stratification methods for identifying patients at risk for SCD, as well as current guideline-driven management strategies for the use of ICDs in patients with CHD and inherited arrhythmia syndromes.
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Affiliation(s)
| | - Cary C Ward
- Division of Cardiology, Duke University Hospital, Durham, NC, USA.,Duke Clinical Research Institute, Duke University Hospital, Durham, NC, USA
| | - Sana M Al-Khatib
- Division of Cardiology, Duke University Hospital, Durham, NC, USA.,Duke Clinical Research Institute, Duke University Hospital, Durham, NC, USA
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17
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Coll M, Pérez-Serra A, Mates J, Del Olmo B, Puigmulé M, Fernandez-Falgueras A, Iglesias A, Picó F, Lopez L, Brugada R, Campuzano O. Incomplete Penetrance and Variable Expressivity: Hallmarks in Channelopathies Associated with Sudden Cardiac Death. BIOLOGY 2017; 7:biology7010003. [PMID: 29278359 PMCID: PMC5872029 DOI: 10.3390/biology7010003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 12/19/2017] [Accepted: 12/22/2017] [Indexed: 12/19/2022]
Abstract
Sudden cardiac death is defined as an unexpected decease of cardiac origin. In individuals under 35 years old, most of these deaths are due to familial arrhythmogenic syndromes of genetic origin, also known as channelopathies. These familial cardiac syndromes commonly follow an autosomal dominant pattern of inheritance. Diagnosis, however, can be difficult, mainly due to incomplete penetrance and variable expressivity, which are hallmarks in these syndromes. The clinical manifestation of these diseases can range from asymptomatic to syncope but sudden death can sometimes be the first symptom of disease. Early identification of at-risk individuals is crucial to prevent a lethal episode. In this review, we will focus on the genetic basis of channelopathies and the effect of genetic and non-genetic modifiers on their phenotypes.
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Affiliation(s)
- Monica Coll
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Salt, Spain.
| | - Alexandra Pérez-Serra
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Salt, Spain.
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain.
| | - Jesus Mates
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Salt, Spain.
| | - Bernat Del Olmo
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Salt, Spain.
| | - Marta Puigmulé
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Salt, Spain.
- Medical Science Department, School of Medicine, University of Girona, 17003 Girona, Spain.
| | | | - Anna Iglesias
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Salt, Spain.
| | - Ferran Picó
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Salt, Spain.
| | - Laura Lopez
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Salt, Spain.
| | - Ramon Brugada
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Salt, Spain.
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain.
- Medical Science Department, School of Medicine, University of Girona, 17003 Girona, Spain.
- Cardiology Service, Hospital Josep Trueta, 17003 Girona, Spain.
| | - Oscar Campuzano
- Cardiovascular Genetics Center, University of Girona-IDIBGI, 17190 Salt, Spain.
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain.
- Medical Science Department, School of Medicine, University of Girona, 17003 Girona, Spain.
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18
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Huang H, Chen YQ, Fan LL, Guo S, Li JJ, Jin JY, Xiang R. Whole-exome sequencing identifies a novel mutation of GPD1L (R189X) associated with familial conduction disease and sudden death. J Cell Mol Med 2017; 22:1350-1354. [PMID: 29077258 PMCID: PMC5783853 DOI: 10.1111/jcmm.13409] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 08/31/2017] [Indexed: 01/21/2023] Open
Abstract
Cardiac conduction disease (CCD) is a serious disorder and the leading cause of mortality worldwide. It is characterized by arrhythmia, syncope or even sudden cardiac death caused by the dysfunction of cardiac voltage‐gated channel. Previous study has demonstrated that mutations in genes encoding voltage‐gated channel and related proteins were the crucial genetic lesion of CCD. In this study, we employed whole‐exome sequencing to explore the potential causative genes in a Chinese family with ventricular tachycardia and syncope. A novel nonsense mutation (c.565C>T/p.R189X) of glycerol‐3‐phosphate dehydrogenase‐like (GPD1L) was identified and co‐segregated with the affected family members. GPD1L is a crucial interacting protein of SCN5A, a gene encoded sodium channel α‐subunit Nav1.5 and mainly associated with Brugada syndrome (BrS). The novel mutation (c.565C>T/p.R189X) may result in a premature stop codon at position 189 in exon 4 of the GPD1L gene and lead to functional haploinsufficiency of GPD1L due to mRNA carrying this mutation will be degraded by nonsense‐mediated mRNA decay, which has been confirmed by Western blot in HEK293 cells transfected HIS‐GPD1L plasmid. The levels of GPD1L decreasing may disturb the function of Nav1.5 and induce arrhythmia and syncope in the end. In conclusion, our study not only further supported the important role of GPD1L in CCD, but also expanded the spectrum of GPD1L mutations and will contribute to the genetic diagnosis and counselling of families with CCD.
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Affiliation(s)
- Hao Huang
- School of Life Sciences, Central South University, Changsha, China
| | - Ya-Qin Chen
- Department of Cardiology, the Second Xiangya Hospital of Central South University, Changsha, China
| | - Liang-Liang Fan
- School of Life Sciences, Central South University, Changsha, China
| | - Shuai Guo
- School of Life Sciences, Central South University, Changsha, China
| | - Jing-Jing Li
- School of Life Sciences, Central South University, Changsha, China
| | - Jie-Yuan Jin
- School of Life Sciences, Central South University, Changsha, China
| | - Rong Xiang
- School of Life Sciences, Central South University, Changsha, China.,Department of Cardiology, the Second Xiangya Hospital of Central South University, Changsha, China
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Furukawa T. Role of head-up tilt table testing in patients with syncope or transient loss of consciousness. J Arrhythm 2017; 33:568-571. [PMID: 29255502 PMCID: PMC5728999 DOI: 10.1016/j.joa.2017.08.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 08/02/2017] [Accepted: 08/08/2017] [Indexed: 01/09/2023] Open
Abstract
The tilt table test (TTT) is a useful method for the management of reflex syncope. However, the TTT is incomplete and has several problems. The indications for this test are established using guidelines. The TTT is not suitable for all syncopal patients. It is currently unclear (1) When should the TTT be used, (2) for which types of patients TTT should be performed, and (3) does the TTT provide useful information to guide indication for pacing therapy for reflex syncope. The answers to these questions appear in recent reports from two guidelines published by the European Society of Cardiology and the Japan Circulation Society. The indications for TTT do not apply to all syncopal patients, but selected patients. For patients with low risks and rare syncopal events, the TTT is not necessary, even when diagnoses are unconfirmed. The TTT is used not only for diagnosis of reflex syncope, but also for many clinical management of several conditions (i.e., exclusion of cardiac syncope). Positive TTT results cannot predict the effects of pacing therapy for reflex syncope. The decision to use pacing therapy should be based on documented electrocardiograms and other findings, including TTT results.
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Affiliation(s)
- Toshiyuki Furukawa
- Syncope Unit, St. Marianna University School of Medicine, Toyoko Hospital, 3-435, Kosugimachi, Nakahara-ku, Kawasaki 211-0063, Japan
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Genetic and epigenetic regulation of arrhythmogenic cardiomyopathy. Biochim Biophys Acta Mol Basis Dis 2017; 1863:2064-2069. [PMID: 28454914 DOI: 10.1016/j.bbadis.2017.04.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 04/11/2017] [Accepted: 04/22/2017] [Indexed: 12/26/2022]
Abstract
Arrhythmogenic cardiomyopathy (AC) is most commonly characterized as a disease of the intercalated disc that promotes abnormal cardiac conduction. Previously, arrhythmogenic cardiomyopathy was frequently referred to as arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D); however, genotype-phenotype studies have defined a broader phenotypic spectrum; with the identification of left-dominant and biventricular subtypes. Molecular insight into AC has primarily focused on mutations in desmosomal proteins and the downstream signaling pathways; however, desmosomal gene mutations can only be identified in approximately 50% of patients with AC. Animal and cellular studies have shown that in addition to abnormal biomechanical properties from changes in desmosome function, crosstalk from the desmosome to the nucleus, gap junctions, and ion channels are implicated in the pathobiology of AC. In this review, we highlight some of the newly identified genetic and epigenetic mechanisms that may lead to the development of AC including the role of the Hippo pathway and microRNAs. This article is part of a Special Issue entitled: Genetic and epigenetic control of heart failure - edited by Jun Ren & Megan Yingmei Zhang.
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