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Byun JY, Han S, Qdaisat A, Park C. Long QT syndrome after using EGFR-TKIs in older patients with advanced non-small cell lung cancer. Expert Opin Drug Saf 2024; 23:1007-1015. [PMID: 38088244 DOI: 10.1080/14740338.2023.2294924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Accepted: 10/31/2023] [Indexed: 12/19/2023]
Abstract
BACKGROUND Long QT syndrome (LQTS) has been reported in older patients with advanced non-small cell lung cancer (NSCLC) following the use of osimertinib, the third-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI). However, there have not been analytic epidemiology studies on this topic. We aimed to compare the risk of LQTS between osimertinib and first/second-generation EGFR-TKIs in older patients with advanced NSCLC. RESEARCH DESIGN AND METHODS This retrospective observational study used the 2006-2019 Surveillance, Epidemiology, and End Results (SEER)-Medicare data and included older patients with advanced NSCLC who were treated with either osimertinib or first/second-generation EGFR-TKIs during 2007-2017. Inverse probability of treatment weighting (IPTW) was used to balance the two groups with propensity scores estimated based on the patients' socioeconomic and clinical characteristics. Crude incidence rate (IR) and adjusted hazard ratio (HR) of the primary outcome, incident LQTS, were estimated. RESULTS A total of 545 and 1,135 patients were included in the osimertinib and first/second-generation EGFR-TKI groups, which increased to 1,614 and 1,659, respectively, after IPTW. The osimertinib group had a higher IR of LQTS (2.62 per 100 person-years, 95% CI 2.03-3.38) compared to the first/second-generation EGFR-TKI group (1.33 per 100 person-years, 95% CI 0.92-1.92). After adjusting for covariates, the osimertinib group had a higher risk of LQTS than the first/second-generation EGFR-TKI group, with an HR of 1.94 (95% CI 1.23-3.08). The increased LQTS risk in the osimertinib group was even higher in females, whites and patients aged ≥ 75. CONCLUSIONS Given the elevated risk of LQTS associated with osimertinib user, close monitoring for cardiac rhythm irregularities of high-risk patients following initiation of EGFR-TKI is recommended.
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Affiliation(s)
- Joo-Young Byun
- Health Outcomes division, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA
- School of Pharmacy, Sungkyunkwan University, Suwon, South Korea
| | - Sola Han
- Health Outcomes division, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA
| | - Aiham Qdaisat
- Department of Emergency Medicine, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Chanhyun Park
- Health Outcomes division, College of Pharmacy, The University of Texas at Austin, Austin, TX, USA
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Yang Y, Yang H, Kiskin FN, Zhang JZ. The new era of cardiovascular research: revolutionizing cardiovascular research with 3D models in a dish. MEDICAL REVIEW (2021) 2024; 4:68-85. [PMID: 38515776 PMCID: PMC10954298 DOI: 10.1515/mr-2023-0059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Accepted: 01/18/2024] [Indexed: 03/23/2024]
Abstract
Cardiovascular research has heavily relied on studies using patient samples and animal models. However, patient studies often miss the data from the crucial early stage of cardiovascular diseases, as obtaining primary tissues at this stage is impracticable. Transgenic animal models can offer some insights into disease mechanisms, although they usually do not fully recapitulate the phenotype of cardiovascular diseases and their progression. In recent years, a promising breakthrough has emerged in the form of in vitro three-dimensional (3D) cardiovascular models utilizing human pluripotent stem cells. These innovative models recreate the intricate 3D structure of the human heart and vessels within a controlled environment. This advancement is pivotal as it addresses the existing gaps in cardiovascular research, allowing scientists to study different stages of cardiovascular diseases and specific drug responses using human-origin models. In this review, we first outline various approaches employed to generate these models. We then comprehensively discuss their applications in studying cardiovascular diseases by providing insights into molecular and cellular changes associated with cardiovascular conditions. Moreover, we highlight the potential of these 3D models serving as a platform for drug testing to assess drug efficacy and safety. Despite their immense potential, challenges persist, particularly in maintaining the complex structure of 3D heart and vessel models and ensuring their function is comparable to real organs. However, overcoming these challenges could revolutionize cardiovascular research. It has the potential to offer comprehensive mechanistic insights into human-specific disease processes, ultimately expediting the development of personalized therapies.
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Affiliation(s)
- Yuan Yang
- Institute of Neurological and Psychiatric Disorders, Shenzhen Bay Laboratory, Shenzhen, Guangdong Province, China
| | - Hao Yang
- Institute of Neurological and Psychiatric Disorders, Shenzhen Bay Laboratory, Shenzhen, Guangdong Province, China
| | - Fedir N. Kiskin
- Institute of Neurological and Psychiatric Disorders, Shenzhen Bay Laboratory, Shenzhen, Guangdong Province, China
| | - Joe Z. Zhang
- Institute of Neurological and Psychiatric Disorders, Shenzhen Bay Laboratory, Shenzhen, Guangdong Province, China
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Al-Azayzih A, Al-Qerem W, Al-Azzam S, Muflih S, Al-Husein BA, Kharaba Z, Kanaan RJ, Rahhal D. Prevalence of Medication Associated with QTc Prolongation Used Among Critically Ill Patients. Vasc Health Risk Manag 2024; 20:27-37. [PMID: 38318252 PMCID: PMC10840412 DOI: 10.2147/vhrm.s438899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 01/19/2024] [Indexed: 02/07/2024] Open
Abstract
Background Acquired prolonged corrected QT (QTc) interval can lead to life-threatening Torsade de Pointes (TdP) arrhythmia. Multiple risk factors including medications, comorbidities, and electrolyte imbalances contribute significantly to acquired manifestations of the QTc prolongation. Critically ill patients are particularly more vulnerable to TdP due to complex medical conditions, aging, and polypharmacy. Objective This study aimed to assess the prevalence of TdP-associated medication prescribing, identify risk factors for QTc prolongation and TdP, and determine primary predictors of high TdP medication usage in critically ill patients in Jordan. Methods We conducted a retrospective cross-sectional analysis of electronic medical records for patients from King Abdullah University Hospital who were admitted to Intensive Care Unit (ICU) between (July 2012-July 2022). We collected data on patients' demographics, clinical characteristics, comorbidities, laboratory results, and prescribed medications. Medications were categorized into three TdP risk levels according to CredibleMeds® assessment tool. Data were analyzed using descriptive statistics and a binary logistic regression model. Results Of the 13,300 patients (58.2% male, median age 62 years). Prescribing prevalence for medications with known TdP risk was 19%, possible risk (24.7%), conditional risk (21.6%), and confirmed conditional risk (8.3%). Common comorbidities included hypertension (40.9%), diabetes (33.3%), and cancer (15.4%). Drugs with known TdP risk included citalopram, amiodarone, clarithromycin, and ciprofloxacin. A binary regression model revealed that as age increased, the odds of TdP associated medication prescribing decreased (OR = 0.989, p < 0.001), while patients on more than five medications had higher odds (OR = 4.281, p < 0.001). Conclusion The study identified a notable prevalence of prescribing for medications with QTc prolongation/TdP risk in critically ill patients. Healthcare providers in the ICU should exercise caution to minimize the inadvertent prescription of TdP associated medications especially among older patients and those with polypharmacy.
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Affiliation(s)
- Ahmad Al-Azayzih
- Department of Clinical Pharmacy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
| | - Walid Al-Qerem
- Faculty of Pharmacy, Al-Zaytoonah University of Jordan, Amman, Jordan
| | - Sayer Al-Azzam
- Department of Clinical Pharmacy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
| | - Suhaib Muflih
- Department of Clinical Pharmacy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
| | - Belal A Al-Husein
- Department of Clinical Pharmacy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
| | - Zelal Kharaba
- College of Pharmacy, AL Ain University, Abu Dhabi, United Arab Emirates
- Honorary Associate Lecturer, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Roaa J Kanaan
- Department of Clinical Pharmacy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
| | - Dania Rahhal
- Department of Clinical Pharmacy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, Jordan
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4
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Meier AB, Zawada D, De Angelis MT, Martens LD, Santamaria G, Zengerle S, Nowak-Imialek M, Kornherr J, Zhang F, Tian Q, Wolf CM, Kupatt C, Sahara M, Lipp P, Theis FJ, Gagneur J, Goedel A, Laugwitz KL, Dorn T, Moretti A. Epicardioid single-cell genomics uncovers principles of human epicardium biology in heart development and disease. Nat Biotechnol 2023; 41:1787-1800. [PMID: 37012447 PMCID: PMC10713454 DOI: 10.1038/s41587-023-01718-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 02/22/2023] [Indexed: 04/05/2023]
Abstract
The epicardium, the mesothelial envelope of the vertebrate heart, is the source of multiple cardiac cell lineages during embryonic development and provides signals that are essential to myocardial growth and repair. Here we generate self-organizing human pluripotent stem cell-derived epicardioids that display retinoic acid-dependent morphological, molecular and functional patterning of the epicardium and myocardium typical of the left ventricular wall. By combining lineage tracing, single-cell transcriptomics and chromatin accessibility profiling, we describe the specification and differentiation process of different cell lineages in epicardioids and draw comparisons to human fetal development at the transcriptional and morphological levels. We then use epicardioids to investigate the functional cross-talk between cardiac cell types, gaining new insights into the role of IGF2/IGF1R and NRP2 signaling in human cardiogenesis. Finally, we show that epicardioids mimic the multicellular pathogenesis of congenital or stress-induced hypertrophy and fibrotic remodeling. As such, epicardioids offer a unique testing ground of epicardial activity in heart development, disease and regeneration.
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Affiliation(s)
- Anna B Meier
- First Department of Medicine, Cardiology, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Munich Heart Alliance, Munich, Germany
| | - Dorota Zawada
- First Department of Medicine, Cardiology, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Munich Heart Alliance, Munich, Germany
| | - Maria Teresa De Angelis
- First Department of Medicine, Cardiology, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Munich Heart Alliance, Munich, Germany
- Department of Experimental and Clinical Medicine, University 'Magna Graecia', Catanzaro, Italy
| | - Laura D Martens
- School of Computation, Information and Technology, Technical University of Munich, Garching, Germany
- Computational Health Center, Helmholtz Center Munich, Neuherberg, Germany
- Helmholtz Association-Munich School for Data Science (MUDS), Munich, Germany
| | - Gianluca Santamaria
- First Department of Medicine, Cardiology, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Munich Heart Alliance, Munich, Germany
- Department of Experimental and Clinical Medicine, University 'Magna Graecia', Catanzaro, Italy
| | - Sophie Zengerle
- First Department of Medicine, Cardiology, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Munich Heart Alliance, Munich, Germany
| | - Monika Nowak-Imialek
- First Department of Medicine, Cardiology, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Munich Heart Alliance, Munich, Germany
| | - Jessica Kornherr
- First Department of Medicine, Cardiology, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Munich Heart Alliance, Munich, Germany
| | - Fangfang Zhang
- First Department of Medicine, Cardiology, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Munich Heart Alliance, Munich, Germany
| | - Qinghai Tian
- Center for Molecular Signaling (PZMS), Institute for Molecular Cell Biology, Research Center for Molecular Imaging and Screening, Medical Faculty, Saarland University, Homburg, Germany
| | - Cordula M Wolf
- German Center for Cardiovascular Research (DZHK), Munich Heart Alliance, Munich, Germany
- Department of Congenital Heart Defects and Pediatric Cardiology, German Heart Center Munich, Technical University of Munich, School of Medicine and Health, Munich, Germany
| | - Christian Kupatt
- First Department of Medicine, Cardiology, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
| | - Makoto Sahara
- Department of Cell and Molecular Biology, Karolinska Institute, Stockholm, Sweden
- Department of Surgery, Yale University School of Medicine, New Haven, CT, USA
| | - Peter Lipp
- Center for Molecular Signaling (PZMS), Institute for Molecular Cell Biology, Research Center for Molecular Imaging and Screening, Medical Faculty, Saarland University, Homburg, Germany
| | - Fabian J Theis
- School of Computation, Information and Technology, Technical University of Munich, Garching, Germany
- Computational Health Center, Helmholtz Center Munich, Neuherberg, Germany
| | - Julien Gagneur
- School of Computation, Information and Technology, Technical University of Munich, Garching, Germany
- Computational Health Center, Helmholtz Center Munich, Neuherberg, Germany
- Institute of Human Genetics, School of Medicine, Technical University of Munich, Munich, Germany
| | - Alexander Goedel
- First Department of Medicine, Cardiology, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- Department of Cell and Molecular Biology, Karolinska Institute, Stockholm, Sweden
| | - Karl-Ludwig Laugwitz
- First Department of Medicine, Cardiology, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
| | - Tatjana Dorn
- First Department of Medicine, Cardiology, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Munich Heart Alliance, Munich, Germany
| | - Alessandra Moretti
- First Department of Medicine, Cardiology, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany.
- Regenerative Medicine in Cardiovascular Diseases, First Department of Medicine, Klinikum rechts der Isar, Technical University of Munich, School of Medicine and Health, Munich, Germany.
- German Center for Cardiovascular Research (DZHK), Munich Heart Alliance, Munich, Germany.
- Department of Surgery, Yale University School of Medicine, New Haven, CT, USA.
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Baracaldo-Santamaría D, Llinás-Caballero K, Corso-Ramirez JM, Restrepo CM, Dominguez-Dominguez CA, Fonseca-Mendoza DJ, Calderon-Ospina CA. Genetic and Molecular Aspects of Drug-Induced QT Interval Prolongation. Int J Mol Sci 2021; 22:8090. [PMID: 34360853 PMCID: PMC8347245 DOI: 10.3390/ijms22158090] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 07/04/2021] [Accepted: 07/06/2021] [Indexed: 12/22/2022] Open
Abstract
Long QT syndromes can be either acquired or congenital. Drugs are one of the many etiologies that may induce acquired long QT syndrome. In fact, many drugs frequently used in the clinical setting are a known risk factor for a prolonged QT interval, thus increasing the chances of developing torsade de pointes. The molecular mechanisms involved in the prolongation of the QT interval are common to most medications. However, there is considerable inter-individual variability in drug response, thus making the application of personalized medicine a relevant aspect in long QT syndrome, in order to evaluate the risk of every individual from a pharmacogenetic standpoint.
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Affiliation(s)
- Daniela Baracaldo-Santamaría
- School of Medicine and Health Sciences, Universidad del Rosario, Bogotá 111221, Colombia; (D.B.-S.); (J.M.C.-R.); (C.A.D.-D.)
| | - Kevin Llinás-Caballero
- GENIUROS Research Group, Center for Research in Genetics and Genomics (CIGGUR), School of Medicine and Health Sciences, Universidad del Rosario, Bogotá 111221, Colombia; (K.L.-C.); (C.M.R.); (D.J.F.-M.)
- Institute for Immunological Research, University of Cartagena, Cartagena 130014, Colombia
| | - Julián Miguel Corso-Ramirez
- School of Medicine and Health Sciences, Universidad del Rosario, Bogotá 111221, Colombia; (D.B.-S.); (J.M.C.-R.); (C.A.D.-D.)
| | - Carlos Martín Restrepo
- GENIUROS Research Group, Center for Research in Genetics and Genomics (CIGGUR), School of Medicine and Health Sciences, Universidad del Rosario, Bogotá 111221, Colombia; (K.L.-C.); (C.M.R.); (D.J.F.-M.)
| | | | - Dora Janeth Fonseca-Mendoza
- GENIUROS Research Group, Center for Research in Genetics and Genomics (CIGGUR), School of Medicine and Health Sciences, Universidad del Rosario, Bogotá 111221, Colombia; (K.L.-C.); (C.M.R.); (D.J.F.-M.)
| | - Carlos Alberto Calderon-Ospina
- GENIUROS Research Group, Center for Research in Genetics and Genomics (CIGGUR), School of Medicine and Health Sciences, Universidad del Rosario, Bogotá 111221, Colombia; (K.L.-C.); (C.M.R.); (D.J.F.-M.)
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Young WJ, Warren HR, Mook-Kanamori DO, Ramírez J, van Duijvenboden S, Orini M, Tinker A, van Heemst D, Lambiase PD, Jukema JW, Munroe PB, Noordam R. Genetically Determined Serum Calcium Levels and Markers of Ventricular Repolarization: A Mendelian Randomization Study in the UK Biobank. CIRCULATION. GENOMIC AND PRECISION MEDICINE 2021; 14:e003231. [PMID: 33887147 PMCID: PMC8208093 DOI: 10.1161/circgen.120.003231] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 04/02/2021] [Indexed: 11/16/2022]
Abstract
BACKGROUND ECG markers of ventricular depolarization and repolarization are associated with an increased risk of arrhythmia and sudden cardiac death. Our prior work indicated lower serum calcium concentrations are associated with longer QT and JT intervals in the general population. Here, we investigate whether serum calcium is a causal risk factor for changes in ECG measures using Mendelian randomization (MR). METHODS Independent lead variants from a newly performed genome-wide association study for serum calcium in >300 000 European-ancestry participants from UK Biobank were used as instrumental variables. Two-sample MR analyses were performed to approximate the causal effect of serum calcium on QT, JT, and QRS intervals using an inverse-weighted method in 76 226 participants not contributing to the serum calcium genome-wide association study. Sensitivity analyses including MR-Egger, weighted-median estimator, and MR pleiotropy residual sum and outlier were performed to test for the presence of horizontal pleiotropy. RESULTS Two hundred five independent lead calcium-associated variants were used as instrumental variables for MR. A decrease of 0.1 mmol/L serum calcium was associated with longer QT (3.01 ms [95% CI, 2.03 to 3.99]) and JT (2.89 ms [1.91 to 3.87]) intervals. A weak association was observed for QRS duration (secondary analyses only). Results were concordant in all sensitivity analyses. CONCLUSIONS These analyses support a causal effect of serum calcium levels on ventricular repolarization, in a middle-aged population of European-ancestry where serum calcium concentrations are likely stable and chronic. Modulation of calcium concentration may, therefore, directly influence cardiovascular disease risk.
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Affiliation(s)
- William J. Young
- Clinical Pharmacology Department, William Harvey Research Institute (W.J.Y., H.R.W., J.R., S.v.D., A.T., P.B.M.), Barts and the London School of Medicine and Dentistry, Queen Mary University of London
- Barts Heart Centre, St Bartholomew’s Hospital, Barts Health NHS trust (W.J.Y., M.O., P.D.L.)
| | - Helen R. Warren
- Clinical Pharmacology Department, William Harvey Research Institute (W.J.Y., H.R.W., J.R., S.v.D., A.T., P.B.M.), Barts and the London School of Medicine and Dentistry, Queen Mary University of London
- NIHR Barts Cardiovascular Biomedical Research Unit (H.R.W., A.T., P.B.M.), Barts and the London School of Medicine and Dentistry, Queen Mary University of London
| | - Dennis O. Mook-Kanamori
- Department of Clinical Epidemiology (D.O.M.-K.), Leiden University Medical Center, the Netherlands
- Department of Public Health and Primary Care (D.O.M.-K.), Leiden University Medical Center, the Netherlands
| | - Julia Ramírez
- Clinical Pharmacology Department, William Harvey Research Institute (W.J.Y., H.R.W., J.R., S.v.D., A.T., P.B.M.), Barts and the London School of Medicine and Dentistry, Queen Mary University of London
- Institute of Cardiovascular Sciences, University of College London, United Kingdom (J.R., S.v.D., M.O., P.D.L.)
| | - Stefan van Duijvenboden
- Clinical Pharmacology Department, William Harvey Research Institute (W.J.Y., H.R.W., J.R., S.v.D., A.T., P.B.M.), Barts and the London School of Medicine and Dentistry, Queen Mary University of London
- Institute of Cardiovascular Sciences, University of College London, United Kingdom (J.R., S.v.D., M.O., P.D.L.)
| | - Michele Orini
- Barts Heart Centre, St Bartholomew’s Hospital, Barts Health NHS trust (W.J.Y., M.O., P.D.L.)
- Institute of Cardiovascular Sciences, University of College London, United Kingdom (J.R., S.v.D., M.O., P.D.L.)
| | - Andrew Tinker
- Clinical Pharmacology Department, William Harvey Research Institute (W.J.Y., H.R.W., J.R., S.v.D., A.T., P.B.M.), Barts and the London School of Medicine and Dentistry, Queen Mary University of London
- NIHR Barts Cardiovascular Biomedical Research Unit (H.R.W., A.T., P.B.M.), Barts and the London School of Medicine and Dentistry, Queen Mary University of London
| | - Diana van Heemst
- Department of Internal Medicine (D.v.H., R.N.), Leiden University Medical Center, the Netherlands
| | - Pier D. Lambiase
- Barts Heart Centre, St Bartholomew’s Hospital, Barts Health NHS trust (W.J.Y., M.O., P.D.L.)
- Institute of Cardiovascular Sciences, University of College London, United Kingdom (J.R., S.v.D., M.O., P.D.L.)
| | - J. Wouter Jukema
- Department of Cardiology (J.W.J.), Leiden University Medical Center, the Netherlands
- Netherlands Heart Institute, Utrecht, the Netherlands (J.W.J.)
| | - Patricia B. Munroe
- Clinical Pharmacology Department, William Harvey Research Institute (W.J.Y., H.R.W., J.R., S.v.D., A.T., P.B.M.), Barts and the London School of Medicine and Dentistry, Queen Mary University of London
- NIHR Barts Cardiovascular Biomedical Research Unit (H.R.W., A.T., P.B.M.), Barts and the London School of Medicine and Dentistry, Queen Mary University of London
| | - Raymond Noordam
- Department of Internal Medicine (D.v.H., R.N.), Leiden University Medical Center, the Netherlands
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7
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Varró A, Tomek J, Nagy N, Virág L, Passini E, Rodriguez B, Baczkó I. Cardiac transmembrane ion channels and action potentials: cellular physiology and arrhythmogenic behavior. Physiol Rev 2020; 101:1083-1176. [PMID: 33118864 DOI: 10.1152/physrev.00024.2019] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Cardiac arrhythmias are among the leading causes of mortality. They often arise from alterations in the electrophysiological properties of cardiac cells and their underlying ionic mechanisms. It is therefore critical to further unravel the pathophysiology of the ionic basis of human cardiac electrophysiology in health and disease. In the first part of this review, current knowledge on the differences in ion channel expression and properties of the ionic processes that determine the morphology and properties of cardiac action potentials and calcium dynamics from cardiomyocytes in different regions of the heart are described. Then the cellular mechanisms promoting arrhythmias in congenital or acquired conditions of ion channel function (electrical remodeling) are discussed. The focus is on human-relevant findings obtained with clinical, experimental, and computational studies, given that interspecies differences make the extrapolation from animal experiments to human clinical settings difficult. Deepening the understanding of the diverse pathophysiology of human cellular electrophysiology will help in developing novel and effective antiarrhythmic strategies for specific subpopulations and disease conditions.
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Affiliation(s)
- András Varró
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,MTA-SZTE Cardiovascular Pharmacology Research Group, Hungarian Academy of Sciences, Szeged, Hungary
| | - Jakub Tomek
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Norbert Nagy
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary.,MTA-SZTE Cardiovascular Pharmacology Research Group, Hungarian Academy of Sciences, Szeged, Hungary
| | - László Virág
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Elisa Passini
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Blanca Rodriguez
- Department of Computer Science, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - István Baczkó
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary
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Jones SA, Walton RD, Morton M, Lancaster MK. K 2p 3.1 protein is expressed as a transmural gradient across the rat left ventricular free wall. J Cardiovasc Electrophysiol 2018; 30:383-391. [PMID: 30516300 PMCID: PMC6446730 DOI: 10.1111/jce.13805] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 11/08/2018] [Accepted: 11/15/2018] [Indexed: 12/25/2022]
Abstract
Introduction K2p3.1, also known as TASK‐1, is a twin‐pore acid‐sensitive repolarizing K+ channel, responsible for a background potassium current that significantly contributes to setting the resting membrane potential of cardiac myocytes. Inhibition of IK2p3.1 alters cardiac repolarization and is proarrhythmogenic. In this study, we have examined the expression of K2p3.1 and function of this channel in tissue and myocytes from across the left ventricular free wall. Methods and Results Using fluorescence immunocytochemistry, the expression of K2p3.1 protein in myocytes from the subendocardial region was found to be twice (205% ± 13.5%) that found in myocytes from the subepicardial region of the left ventricle (100% ± 5.3%). The left ventricular free wall exhibited a marked transmural gradient of K2p3.1 protein expression. Western blot analysis confirmed significantly higher K2p3.1 protein expression in subendocardial tissue (156% ± 2.5%) than subepicardial tissue (100% ± 5.0%). However, there was no difference in K2p3.1 messenger RNA expression. Whole‐cell patch clamp identified IK2p3.1 current density to be significantly greater in myocytes isolated from the subendocardium (7.66 ± 0.53 pA/pF) compared with those from the subepicardium (3.47 ± 0.74 pA/pF). Conclusions This is the first study to identify a transmural gradient of K2p3.1 in the left ventricle. This gradient has implications for understanding ventricular arrhythmogenesis under conditions of ischemia but also in response to other modulatory factors, such as adrenergic stimulation and the presence of anesthetics that inhibits or activates this channel.
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Affiliation(s)
- Sandra A Jones
- Department of Biomedical Sciences, Department Faculty of Health Sciences, University of Hull, Hull, UK
| | - Richard D Walton
- Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Université de Bordeaux, Bordeaux, France.,Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux, Bordeaux, France.,L'Institut de Rythmologie et Modélisation Cardiaque LIRYC, Fondation Bordeaux Université, Bordeaux, France
| | | | - Matthew K Lancaster
- Faculty of Biological Sciences, School of Biomedical Sciences, University of Leeds, Leeds, UK
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9
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Sicouri S, Antzelevitch C. Mechanisms Underlying the Actions of Antidepressant and Antipsychotic Drugs That Cause Sudden Cardiac Arrest. Arrhythm Electrophysiol Rev 2018; 7:199-209. [PMID: 30416734 PMCID: PMC6141916 DOI: 10.15420/aer.2018.29.2] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 06/19/2018] [Indexed: 12/18/2022] Open
Abstract
A number of antipsychotic and antidepressant drugs are known to increase the risk of ventricular arrhythmias and sudden cardiac death. Based largely on a concern over the development of life-threatening arrhythmias, a number of antipsychotic drugs have been temporarily or permanently withdrawn from the market or their use restricted. While many antidepressants and antipsychotics have been linked to QT prolongation and the development of torsade de pointes arrhythmias, some have been associated with a Brugada syndrome phenotype and the development of polymorphic ventricular arrhythmias. This article examines the arrhythmic liability of antipsychotic and antidepressant drugs capable of inducing long QT and/or Brugada syndrome phenotypes. The goal of this article is to provide an update on the ionic and cellular mechanisms thought to be involved in, and the genetic and environmental factors that predispose to, the development of cardiac arrhythmias and sudden cardiac death among patients taking antidepressant and antipsychotic drugs that are in clinical use.
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Affiliation(s)
- Serge Sicouri
- Lankenau Institute for Medical ResearchWynnewood, PA, USA
| | - Charles Antzelevitch
- Lankenau Institute for Medical ResearchWynnewood, PA, USA
- Lankenau Heart InstituteWynnewood, PA
- Sidney Kimmel Medical College of Thomas Jefferson UniversityPhiladelphia, PA, USA
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10
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Di Diego JM, Antzelevitch C. J wave syndromes as a cause of malignant cardiac arrhythmias. Pacing Clin Electrophysiol 2018; 41:684-699. [PMID: 29870068 PMCID: PMC6281786 DOI: 10.1111/pace.13408] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 05/05/2018] [Indexed: 12/19/2022]
Abstract
The J wave syndromes, including the Brugada (BrS) and early repolarization (ERS) syndromes, are characterized by the manifestation of prominent J waves in the electrocardiogram appearing as an ST segment elevation and the development of life-threatening cardiac arrhythmias. BrS and ERS differ with respect to the magnitude and lead location of abnormal J waves and are thought to represent a continuous spectrum of phenotypic expression termed J wave syndromes. Despite over 25 years of intensive research, risk stratification and the approach to therapy of these two inherited cardiac arrhythmia syndromes are still rapidly evolving. Our objective in this review is to provide an integrated synopsis of the clinical characteristics, risk stratifiers, as well as the molecular, ionic, cellular, and genetic mechanisms underlying these two syndromes that have captured the interest and attention of the cardiology community over the past two decades.
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Affiliation(s)
| | - Charles Antzelevitch
- Lankenau Institute for Medical Research, Wynnewood PA
- Lankenau Heart Institute, Wynnewood, PA
- Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia PA
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11
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Li M, Ramos LG. Drug-Induced QT Prolongation And Torsades de Pointes. P & T : A PEER-REVIEWED JOURNAL FOR FORMULARY MANAGEMENT 2017; 42:473-477. [PMID: 28674475 PMCID: PMC5481298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Torsades de pointes (TdP)-an uncommon but life-threatening polymorphic ventricular tachycardia-is almost always drug induced. The authors describe the causes, risk factors, symptoms, diagnosis, and treatment of TdP.
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12
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Antzelevitch C, Yan GX, Ackerman MJ, Borggrefe M, Corrado D, Guo J, Gussak I, Hasdemir C, Horie M, Huikuri H, Ma C, Morita H, Nam GB, Sacher F, Shimizu W, Viskin S, Wilde AA. J-Wave syndromes expert consensus conference report: Emerging concepts and gaps in knowledge. Europace 2017; 19:665-694. [PMID: 28431071 PMCID: PMC5834028 DOI: 10.1093/europace/euw235] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
| | - Gan-Xin Yan
- Lankenau Medical Center, Wynnewood, Pennsylvania
| | - Michael J. Ackerman
- Departments of Cardiovascular Diseases, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics, Divisions of Heart Rhythm Services and Pediatric Cardiology, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester,Minnesota
| | - Martin Borggrefe
- 1st Department of Medicine–Cardiology, University Medical Centre Mannheim, and DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Domenico Corrado
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padua Medical School, Padua, Italy
| | - Jihong Guo
- Division of Cardiology, Peking University of People's Hospital, Beijing, China
| | - Ihor Gussak
- Rutgers University, New Brunswick, New Jersey
| | - Can Hasdemir
- Department of Cardiology, Ege University School of Medicine, Izmir, Turkey
| | - Minoru Horie
- Shiga University of Medical Sciences, Ohtsu, Shiga, Japan
| | - Heikki Huikuri
- Research Unit of Internal Medicine, Medical Research Center, Oulu University Hospital, and University of Oulu, Oulu, Finland
| | - Changsheng Ma
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, National Clinical Research Center for Cardiovascular Diseases, Beijing, China
| | - Hiroshi Morita
- Department of Cardiovascular Therapeutics, Okayama University Graduate School of Medicine, Okayama, Japan
| | - Gi-Byoung Nam
- Heart Institute, Asan Medical Center, and Department of Internal Medicine, University of Ulsan College of Medicine Seoul, Seoul, Korea
| | - Frederic Sacher
- Bordeaux University Hospital, LIRYC Institute/INSERM 1045, Bordeaux, France
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan
| | - Sami Viskin
- Tel-Aviv Sourasky Medical Center and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Arthur A.M. Wilde
- Heart Center, Department of Clinical and Experimental Cardiology, Academic Medical Center, University of Amsterdam, the Netherlands and Princess Al-Jawhara Al-Brahim Centre of Excellence in Research of Hereditary Disorders, Jeddah, Kingdom of Saudi Arabia
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13
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Anumonwo JM. Reprogramming of Cardiac Repolarization: Notch Signals a Potential Role for Epigenetic Transcriptional Events. Circ Res 2016; 119:1265-1266. [PMID: 27932467 DOI: 10.1161/circresaha.116.310156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Justus M Anumonwo
- From the Department of Internal Medicine (Cardiovascular Medicine) and Department of Molecular and Integrative Physiology (Medical School), University of Michigan, Ann Arbor.
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14
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Transmural electrophysiological heterogeneity, the T-wave and ventricular arrhythmias. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2016; 122:202-214. [DOI: 10.1016/j.pbiomolbio.2016.05.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 04/21/2016] [Accepted: 05/03/2016] [Indexed: 01/05/2023]
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15
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Antzelevitch C, Yan GX, Ackerman MJ, Borggrefe M, Corrado D, Guo J, Gussak I, Hasdemir C, Horie M, Huikuri H, Ma C, Morita H, Nam GB, Sacher F, Shimizu W, Viskin S, Wilde AA. J-Wave syndromes expert consensus conference report: Emerging concepts and gaps in knowledge. J Arrhythm 2016; 32:315-339. [PMID: 27761155 PMCID: PMC5063270 DOI: 10.1016/j.joa.2016.07.002] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
| | - Gan-Xin Yan
- Lankenau Medical Center, Wynnewood, PA, United States
| | - Michael J. Ackerman
- Departments of Cardiovascular Diseases, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics, Divisions of Heart Rhythm Services and Pediatric Cardiology, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, MN, United States
| | - Martin Borggrefe
- 1st Department of Medicine–Cardiology, University Medical Centre Mannheim, and DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Domenico Corrado
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padua Medical School, Padua, Italy
| | - Jihong Guo
- Division of Cardiology, Peking University of People׳s Hospital, Beijing, China
| | - Ihor Gussak
- Rutgers University, New Brunswick, NJ, United States
| | - Can Hasdemir
- Department of Cardiology, Ege University School of Medicine, Izmir, Turkey
| | - Minoru Horie
- Shiga University of Medical Sciences, Ohtsu, Shiga, Japan
| | - Heikki Huikuri
- Research Unit of Internal Medicine, Medical Research Center, Oulu University Hospital, and University of Oulu, Oulu, Finland
| | - Changsheng Ma
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, National Clinical Research Center for Cardiovascular Diseases, Beijing, China
| | - Hiroshi Morita
- Department of Cardiovascular Therapeutics, Okayama University Graduate School of Medicine, Okayama, Japan
| | - Gi-Byoung Nam
- Heart Institute, Asian Medical Center, and Department of Internal Medicine, University of Ulsan College of Medicine Seoul, Seoul, South Korea
| | - Frederic Sacher
- Bordeaux University Hospital, LIRYC Institute/INSERM 1045, Bordeaux, France
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan
| | - Sami Viskin
- Tel-Aviv Sourasky Medical Center and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Arthur A.M. Wilde
- Heart Center, Department of Clinical and Experimental Cardiology, Academic Medical Center, University of Amsterdam, The Netherlands
- Jawhara Al-Brahim Centre of Excellence in Research of Hereditary Disorders, Jeddah, Saudi Arabia
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16
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Antzelevitch C, Yan GX, Ackerman MJ, Borggrefe M, Corrado D, Guo J, Gussak I, Hasdemir C, Horie M, Huikuri H, Ma C, Morita H, Nam GB, Sacher F, Shimizu W, Viskin S, Wilde AAM. J-Wave syndromes expert consensus conference report: Emerging concepts and gaps in knowledge. Heart Rhythm 2016; 13:e295-324. [PMID: 27423412 PMCID: PMC5035208 DOI: 10.1016/j.hrthm.2016.05.024] [Citation(s) in RCA: 228] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Indexed: 12/16/2022]
Affiliation(s)
| | - Gan-Xin Yan
- Lankenau Medical Center, Wynnewood, Pennsylvania
| | - Michael J Ackerman
- Departments of Cardiovascular Diseases, Pediatrics, and Molecular Pharmacology & Experimental Therapeutics, Divisions of Heart Rhythm Services and Pediatric Cardiology, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester,Minnesota
| | - Martin Borggrefe
- 1st Department of Medicine-Cardiology, University Medical Centre Mannheim, and DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, Mannheim, Germany
| | - Domenico Corrado
- Department of Cardiac, Thoracic and Vascular Sciences, University of Padua Medical School, Padua, Italy
| | - Jihong Guo
- Division of Cardiology, Peking University of People's Hospital, Beijing, China
| | - Ihor Gussak
- Rutgers University, New Brunswick, New Jersey
| | - Can Hasdemir
- Department of Cardiology, Ege University School of Medicine, Izmir, Turkey
| | - Minoru Horie
- Shiga University of Medical Sciences, Ohtsu, Shiga, Japan
| | - Heikki Huikuri
- Research Unit of Internal Medicine, Medical Research Center, Oulu University Hospital, and University of Oulu, Oulu, Finland
| | - Changsheng Ma
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, National Clinical Research Center for Cardiovascular Diseases, Beijing, China
| | - Hiroshi Morita
- Department of Cardiovascular Therapeutics, Okayama University Graduate School of Medicine, Okayama, Japan
| | - Gi-Byoung Nam
- Heart Institute, Asan Medical Center, and Department of Internal Medicine, University of Ulsan College of Medicine Seoul, Seoul, Korea
| | - Frederic Sacher
- Bordeaux University Hospital, LIRYC Institute/INSERM 1045, Bordeaux, France
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan
| | - Sami Viskin
- Tel-Aviv Sourasky Medical Center and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Arthur A M Wilde
- Heart Center, Department of Clinical and Experimental Cardiology, Academic Medical Center, University of Amsterdam, the Netherlands and Princess Al-Jawhara Al-Brahim Centre of Excellence in Research of Hereditary Disorders, Jeddah, Kingdom of Saudi Arabia
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17
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Lang CN, Koren G, Odening KE. Transgenic rabbit models to investigate the cardiac ion channel disease long QT syndrome. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2016; 121:142-56. [PMID: 27210307 DOI: 10.1016/j.pbiomolbio.2016.05.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 05/01/2016] [Indexed: 12/13/2022]
Abstract
Long QT syndrome (LQTS) is a rare inherited channelopathy caused mainly by different mutations in genes encoding for cardiac K(+) or Na(+) channels, but can also be caused by commonly used ion-channel-blocking and QT-prolonging drugs, thus affecting a much larger population. To develop novel diagnostic and therapeutic strategies to improve the clinical management of these patients, a thorough understanding of the pathophysiological mechanisms of arrhythmogenesis and potential pharmacological targets is needed. Drug-induced and genetic animal models of various species have been generated and have been instrumental for identifying pro-arrhythmic triggers and important characteristics of the arrhythmogenic substrate in LQTS. However, due to species differences in features of cardiac electrical function, these different models do not entirely recapitulate all aspects of the human disease. In this review, we summarize advantages and shortcomings of different drug-induced and genetically mediated LQTS animal models - focusing on mouse and rabbit models since these represent the most commonly used small animal models for LQTS that can be subjected to genetic manipulation. In particular, we highlight the different aspects of arrhythmogenic mechanisms, pro-arrhythmic triggering factors, anti-arrhythmic agents, and electro-mechanical dysfunction investigated in transgenic LQTS rabbit models and their translational application for the clinical management of LQTS patients in detail. Transgenic LQTS rabbits have been instrumental to increase our understanding of the role of spatial and temporal dispersion of repolarization to provide an arrhythmogenic substrate, genotype-differences in the mechanisms for early afterdepolarization formation and arrhythmia maintenance, mechanisms of hormonal modification of arrhythmogenesis and regional heterogeneities in electro-mechanical dysfunction in LQTS.
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Affiliation(s)
- C N Lang
- Department of Cardiology and Angiology I, University Heart Center Freiburg, Medical Center - University of Freiburg, Germany; Faculty of Medicine, University of Freiburg, Germany
| | - G Koren
- Cardiovascular Research Center, Division of Cardiology, Rhode Island Hospital, Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - K E Odening
- Department of Cardiology and Angiology I, University Heart Center Freiburg, Medical Center - University of Freiburg, Germany; Faculty of Medicine, University of Freiburg, Germany.
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18
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Electro-mechanical dysfunction in long QT syndrome: Role for arrhythmogenic risk prediction and modulation by sex and sex hormones. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2015; 120:255-69. [PMID: 26718598 DOI: 10.1016/j.pbiomolbio.2015.12.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 11/26/2015] [Accepted: 12/15/2015] [Indexed: 12/24/2022]
Abstract
Long QT syndrome (LQTS) is a congenital arrhythmogenic channelopathy characterized by impaired cardiac repolarization. Increasing evidence supports the notion that LQTS is not purely an "electrical" disease but rather an "electro-mechanical" disease with regionally heterogeneously impaired electrical and mechanical cardiac function. In the first part, this article reviews current knowledge on electro-mechanical (dys)function in LQTS, clinical consequences of the observed electro-mechanical dysfunction, and potential underlying mechanisms. Since several novel imaging techniques - Strain Echocardiography (SE) and Magnetic Resonance Tissue Phase Mapping (TPM) - are applied in clinical and experimental settings to assess the (regional) mechanical function, advantages of these non-invasive techniques and their feasibility in the clinical routine are particularly highlighted. The second part provides novel insights into sex differences and sex hormone effects on electro-mechanical cardiac function in a transgenic LQT2 rabbit model. Here we demonstrate that female LQT2 rabbits exhibit a prolonged time to diastolic peak - as marker for contraction duration and early relaxation - compared to males. Chronic estradiol-treatment enhances these differences in time to diastolic peak even more and additionally increases the risk for ventricular arrhythmia. Importantly, time to diastolic peak is particularly prolonged in rabbits exhibiting ventricular arrhythmia - regardless of hormone treatment - contrasting with a lack of differences in QT duration between symptomatic and asymptomatic LQT2 rabbits. This indicates the potential added value of the assessment of mechanical dysfunction in future risk stratification of LQTS patients.
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19
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Stancescu M, Molnar P, McAleer CW, McLamb W, Long CJ, Oleaga C, Prot JM, Hickman JJ. A phenotypic in vitro model for the main determinants of human whole heart function. Biomaterials 2015; 60:20-30. [PMID: 25978005 DOI: 10.1016/j.biomaterials.2015.04.035] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 04/09/2015] [Accepted: 04/14/2015] [Indexed: 11/24/2022]
Abstract
This article details the construction and testing of a phenotypic assay system that models in vivo cardiac function in a parallel in vitro environment with human stem cell derived cardiomyocytes. The major determinants of human whole-heart function were experimentally modeled by integrating separate 2D cellular systems with BioMicroelectromechanical Systems (BioMEMS) constructs. The model features a serum-free defined medium to enable both acute and chronic evaluation of drugs and toxins. The integration of data from both systems produced biologically relevant predictions of cardiac function in response to varying concentrations of selected drugs. Sotalol, norepinephrine and verapamil were shown to affect the measured parameters according to their specific mechanism of action, in agreement with clinical data. This system is applicable for cardiac side effect assessment, general toxicology, efficacy studies, and evaluation of in vitro cellular disease models in body-on-a-chip systems.
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Affiliation(s)
- Maria Stancescu
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - Peter Molnar
- Department of Zoology, University of West Hungary, Szombathely H-9700, Hungary; Biomedical Engineering, Cornell University, Department of Biomedical Engineering, 115 Weill Hall, Ithaca, NY 14853, USA
| | - Christopher W McAleer
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - William McLamb
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - Christopher J Long
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - Carlota Oleaga
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA
| | - Jean-Matthieu Prot
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA; Biomedical Engineering, Cornell University, Department of Biomedical Engineering, 115 Weill Hall, Ithaca, NY 14853, USA
| | - James J Hickman
- NanoScience Technology Center, University of Central Florida, 12424 Research Parkway, Suite 400, Orlando, FL 32826, USA.
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Li J, Xie D, Huang J, Lv F, Shi D, Liu Y, Lin L, Geng L, Wu Y, Liang D, Chen YH. Cold-Inducible RNA-Binding Protein Regulates Cardiac Repolarization by Targeting Transient Outward Potassium Channels. Circ Res 2015; 116:1655-9. [DOI: 10.1161/circresaha.116.306287] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 03/12/2015] [Indexed: 02/03/2023]
Affiliation(s)
- Jun Li
- From the Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine (J.L., D.X., J.H., F.L., D.S., Y.L., L.L., L.G., Y.W., D.L., Y.-H.C.); Institute of Medical Genetics, Tongji University (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Department of Cardiology, East Hospital, Tongji University School of
| | - Duanyang Xie
- From the Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine (J.L., D.X., J.H., F.L., D.S., Y.L., L.L., L.G., Y.W., D.L., Y.-H.C.); Institute of Medical Genetics, Tongji University (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Department of Cardiology, East Hospital, Tongji University School of
| | - Jian Huang
- From the Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine (J.L., D.X., J.H., F.L., D.S., Y.L., L.L., L.G., Y.W., D.L., Y.-H.C.); Institute of Medical Genetics, Tongji University (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Department of Cardiology, East Hospital, Tongji University School of
| | - Fei Lv
- From the Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine (J.L., D.X., J.H., F.L., D.S., Y.L., L.L., L.G., Y.W., D.L., Y.-H.C.); Institute of Medical Genetics, Tongji University (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Department of Cardiology, East Hospital, Tongji University School of
| | - Dan Shi
- From the Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine (J.L., D.X., J.H., F.L., D.S., Y.L., L.L., L.G., Y.W., D.L., Y.-H.C.); Institute of Medical Genetics, Tongji University (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Department of Cardiology, East Hospital, Tongji University School of
| | - Yi Liu
- From the Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine (J.L., D.X., J.H., F.L., D.S., Y.L., L.L., L.G., Y.W., D.L., Y.-H.C.); Institute of Medical Genetics, Tongji University (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Department of Cardiology, East Hospital, Tongji University School of
| | - Li Lin
- From the Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine (J.L., D.X., J.H., F.L., D.S., Y.L., L.L., L.G., Y.W., D.L., Y.-H.C.); Institute of Medical Genetics, Tongji University (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Department of Cardiology, East Hospital, Tongji University School of
| | - Li Geng
- From the Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine (J.L., D.X., J.H., F.L., D.S., Y.L., L.L., L.G., Y.W., D.L., Y.-H.C.); Institute of Medical Genetics, Tongji University (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Department of Cardiology, East Hospital, Tongji University School of
| | - Yufei Wu
- From the Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine (J.L., D.X., J.H., F.L., D.S., Y.L., L.L., L.G., Y.W., D.L., Y.-H.C.); Institute of Medical Genetics, Tongji University (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Department of Cardiology, East Hospital, Tongji University School of
| | - Dandan Liang
- From the Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine (J.L., D.X., J.H., F.L., D.S., Y.L., L.L., L.G., Y.W., D.L., Y.-H.C.); Institute of Medical Genetics, Tongji University (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Department of Cardiology, East Hospital, Tongji University School of
| | - Yi-Han Chen
- From the Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine (J.L., D.X., J.H., F.L., D.S., Y.L., L.L., L.G., Y.W., D.L., Y.-H.C.); Institute of Medical Genetics, Tongji University (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Research Center for Translational Medicine, East Hospital, Tongji University School of Medicine (J.L., D.S., Y.L., L.L., D.L., Y.-H.C.); Department of Cardiology, East Hospital, Tongji University School of
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Goutelle S, Sidolle E, Ducher M, Caron J, Timour Q, Nony P, Gouraud A. Determinants of torsades de pointes in older patients with drug-associated long QT syndrome: a case-control study. Drugs Aging 2015; 31:601-9. [PMID: 24923384 DOI: 10.1007/s40266-014-0188-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE Many elderly patients are routinely exposed to drugs that may prolong the cardiac QT interval and cause Torsades de pointes (TdP). However, predictors of TdP in patients with drug-associated long QT syndrome (LQTS) are not fully understood, especially in the geriatric population. The objective of this study was to identify risk factors of TdP in elderly patients with drug-associated LQTS. METHODS In this retrospective, case-control study, documented reports of drug-associated LQTS plus TdP (n = 125) and LQTS without TdP (n = 81) in patients ≥65 years of age were retrieved from the French Pharmacovigilance Database over a 10-year period. Available clinical, biological, and drug therapy data were compared in the two groups and logistic regression was performed to identify significant predictors of TdP. RESULTS The uncorrected QT interval was significantly longer in patients with TdP than in patients without TdP (577 ± 79 vs. 519 ± 68 ms; p = 0.0001). The number of drugs with a known risk of TdP administered to each patient was not a predictor of arrhythmia, nor was female gender. Logistic regression analysis identified the uncorrected QT interval as the only significant predictor of TdP. The receiver operating characteristic curve analysis was characterized by an area under the curve of 0.77 (95 % confidence interval 0.64-0.88) and a QT cutoff of 550 ms. CONCLUSION The uncorrected QT interval was significantly associated with the probability of TdP in elderly patients with acquired, drug-associated LQTS.
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Affiliation(s)
- Sylvain Goutelle
- Hospices Civils de Lyon, Groupement Hospitalier de Gériatrie, Service Pharmaceutique, Lyon, France,
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Boukens BJ, Rivaud MR, Rentschler S, Coronel R. Misinterpretation of the mouse ECG: 'musing the waves of Mus musculus'. J Physiol 2014; 592:4613-26. [PMID: 25260630 DOI: 10.1113/jphysiol.2014.279380] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The ECG is a primary diagnostic tool in patients suffering from heart disease, underscoring the importance of understanding factors contributing to normal and abnormal electrical patterns. Over the past few decades, transgenic mouse models have been increasingly used to study pathophysiological mechanisms of human heart diseases. In order to allow extrapolation of insights gained from murine models to the human condition, knowledge of the similarities and differences between the mouse and human ECG is of crucial importance. In this review, we briefly discuss the physiological mechanisms underlying differences between the baseline ECG of humans and mice, and provide a framework for understanding how these inherent differences are relevant to the interpretation of the mouse ECG during pathology and to the translation of the results from the mouse to man.
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Affiliation(s)
- Bastiaan J Boukens
- Department of Biomedical Engineering, Washington University, St Louis, MO 63119, USA
| | - Mathilde R Rivaud
- Department of Experimental Cardiology, Academic Medical Center, Amsterdam, The Netherlands
| | - Stacey Rentschler
- Department of Medicine, Cardiovascular Division, and Department of Developmental Biology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Ruben Coronel
- Department of Experimental Cardiology, Academic Medical Center, Amsterdam, The Netherlands L'Institut de RYthmologie et de modélisation Cardiaque (LIRYC), Université Bordeaux Segalen, Bordeaux, France
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Liu T, Takimoto E, Dimaano VL, DeMazumder D, Kettlewell S, Smith G, Sidor A, Abraham TP, O'Rourke B. Inhibiting mitochondrial Na+/Ca2+ exchange prevents sudden death in a Guinea pig model of heart failure. Circ Res 2014; 115:44-54. [PMID: 24780171 DOI: 10.1161/circresaha.115.303062] [Citation(s) in RCA: 137] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
RATIONALE In cardiomyocytes from failing hearts, insufficient mitochondrial Ca(2+) accumulation secondary to cytoplasmic Na(+) overload decreases NAD(P)H/NAD(P)(+) redox potential and increases oxidative stress when workload increases. These effects are abolished by enhancing mitochondrial Ca(2+) with acute treatment with CGP-37157 (CGP), an inhibitor of the mitochondrial Na(+)/Ca(2+) exchanger. OBJECTIVE Our aim was to determine whether chronic CGP treatment mitigates contractile dysfunction and arrhythmias in an animal model of heart failure (HF) and sudden cardiac death (SCD). METHODS AND RESULTS Here, we describe a novel guinea pig HF/SCD model using aortic constriction combined with daily β-adrenergic receptor stimulation (ACi) and show that chronic CGP treatment (ACi plus CGP) attenuates cardiac hypertrophic remodeling, pulmonary edema, and interstitial fibrosis and prevents cardiac dysfunction and SCD. In the ACi group 4 weeks after pressure overload, fractional shortening and the rate of left ventricular pressure development decreased by 36% and 32%, respectively, compared with sham-operated controls; in contrast, cardiac function was completely preserved in the ACi plus CGP group. CGP treatment also significantly reduced the incidence of premature ventricular beats and prevented fatal episodes of ventricular fibrillation, but did not prevent QT prolongation. Without CGP treatment, mortality was 61% in the ACi group <4 weeks of aortic constriction, whereas the death rate in the ACi plus CGP group was not different from sham-operated animals. CONCLUSIONS The findings demonstrate the critical role played by altered mitochondrial Ca(2+) dynamics in the development of HF and HF-associated SCD; moreover, they reveal a novel strategy for treating SCD and cardiac decompensation in HF.
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Affiliation(s)
- Ting Liu
- From the Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (T.L., E.T., V.L.D., D.D., A.S., T.P.A., B.O.'R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.K., G.S.)
| | - Eiki Takimoto
- From the Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (T.L., E.T., V.L.D., D.D., A.S., T.P.A., B.O.'R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.K., G.S.)
| | - Veronica L Dimaano
- From the Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (T.L., E.T., V.L.D., D.D., A.S., T.P.A., B.O.'R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.K., G.S.)
| | - Deeptankar DeMazumder
- From the Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (T.L., E.T., V.L.D., D.D., A.S., T.P.A., B.O.'R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.K., G.S.)
| | - Sarah Kettlewell
- From the Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (T.L., E.T., V.L.D., D.D., A.S., T.P.A., B.O.'R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.K., G.S.)
| | - Godfrey Smith
- From the Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (T.L., E.T., V.L.D., D.D., A.S., T.P.A., B.O.'R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.K., G.S.)
| | - Agnieszka Sidor
- From the Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (T.L., E.T., V.L.D., D.D., A.S., T.P.A., B.O.'R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.K., G.S.)
| | - Theodore P Abraham
- From the Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (T.L., E.T., V.L.D., D.D., A.S., T.P.A., B.O.'R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.K., G.S.)
| | - Brian O'Rourke
- From the Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD (T.L., E.T., V.L.D., D.D., A.S., T.P.A., B.O.'R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (S.K., G.S.).
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Xue J, Rowlandson I. The detection of T-wave variation linked to arrhythmic risk: an industry perspective. J Electrocardiol 2013; 46:597-607. [PMID: 24210024 DOI: 10.1016/j.jelectrocard.2013.08.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Indexed: 01/10/2023]
Abstract
Although the scientific literature contains ample descriptions of peculiar patterns of repolarization linked to arrhythmic risk, the objective quantification and classification of these patterns continues to be a challenge that impacts their widespread adoption in clinical practice. To advance the science, computerized algorithms spawned in the academic environment have been essential in order to find, extract and measure these patterns. However, outside the strict control of a core lab, these algorithms are exposed to poor quality signals and need to be effective in the presence of different forms of noise that can either obscure or mimic the T-wave variation (TWV) of interest. To provide a practical solution that can be verified and validated for the market, important tradeoffs need to be made that are based on an intimate understanding of the end-user as well as the key characteristics of either the signal or the noise that can be used by the signal processing engineer to best differentiate them. To illustrate this, two contemporary medical devices used for quantifying T-wave variation are presented, including the modified moving average (MMA) for the detection of T-wave Alternans (TWA) and the quantification of T-wave shape as inputs to the Morphology Combination Score (MCS) for the trending of drug-induced repolarization abnormalities.
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Polymorphic Ventricular Tachycardia—Part I: Structural Heart Disease and Acquired Causes. Curr Probl Cardiol 2013; 38:463-96. [DOI: 10.1016/j.cpcardiol.2013.07.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Kusha M, Masse S, Farid T, Urch B, Silverman F, Brook RD, Gold DR, Mangat I, Speck M, Nair K, Poku K, Meyer C, Mittleman MA, Wellenius GA, Nanthakumar K. Controlled exposure study of air pollution and T-wave alternans in volunteers without cardiovascular disease. ENVIRONMENTAL HEALTH PERSPECTIVES 2012; 120:1157-1161. [PMID: 22552907 PMCID: PMC3440072 DOI: 10.1289/ehp.1104171] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 05/02/2012] [Indexed: 05/31/2023]
Abstract
BACKGROUND Epidemiological studies have assessed T-wave alternans (TWA) as a possible mechanism of cardiac arrhythmias related to air pollution in high-risk subjects and have reported associations with increased TWA magnitude. OBJECTIVE In this controlled human exposure study, we assessed the impact of exposure to concentrated ambient particulate matter (CAP) and ozone (O3) on T-wave alternans in resting volunteers without preexisting cardiovascular disease. METHODS Seventeen participants without preexisting cardiovascular disease were randomized to filtered air (FA), CAP (150 μg/m3), O3 (120 ppb), or combined CAP + O3 exposures for 2 hr. Continuous electrocardiograms (ECGs) were recorded at rest and T-wave alternans (TWA) was computed by modified moving average analysis with QRS alignment for the artifact-free intervals of 20 beats along the V2 and V5 leads. Exposure-induced changes in the highest TWA magnitude (TWAMax) were estimated for the first and last 5 min of each exposure (TWAMax_Early and TWAMax_Late respectively). ΔTWAMax (Late-Early) were compared among exposure groups using analysis of variance. RESULTS Mean ± SD values for ΔTWAMax were -2.1 ± 0.4, -2.7 ± 1.1, -1.9 ± 1.5, and -1.2 ± 1.5 in FA, CAP, O3, and CAP + O3 exposure groups, respectively. No significant differences were observed between pollutant exposures and FA. CONCLUSION In our study of 17 volunteers who had no preexisting cardiovascular disease, we did not observe significant changes in T-wave alternans after 2-hr exposures to CAP, O3, or combined CAP + O3. This finding, however, does not preclude the possibility of pollution-related effects on TWA at elevated heart rates, such as during exercise, or the possibility of delayed responses.
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Affiliation(s)
- Marjan Kusha
- Division of Cardiology, Toronto General Hospital, Toronto, Ontario, Canada
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Sivagangabalan G, Spears D, Masse S, Urch B, Brook RD, Silverman F, Gold DR, Lukic KZ, Speck M, Kusha M, Farid T, Poku K, Shi E, Floras J, Nanthakumar K. The effect of air pollution on spatial dispersion of myocardial repolarization in healthy human volunteers. J Am Coll Cardiol 2011; 57:198-206. [PMID: 21211691 DOI: 10.1016/j.jacc.2010.08.625] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Revised: 07/28/2010] [Accepted: 08/10/2010] [Indexed: 11/17/2022]
Abstract
OBJECTIVES We tested the hypothesis that exposure to concentrated ambient particles (CAP) and/or ozone (O(3)) would increase dispersion of ventricular repolarization. BACKGROUND Elevated levels of air pollution are associated with cardiac arrhythmias through mechanisms yet to be elucidated. METHODS Each of 25 volunteers (18 to 50 years of age) had four 2-h exposures to 150 μg/m(3) CAP; 120 parts per billion O(3); CAP + O(3); and filtered air (FA). Exposure-induced changes (Δ = 5-min epochs at end-start) in spatial dispersion of repolarization were determined from continuous 12-lead electrocardiographic recording. RESULTS Spatial dispersion of repolarization assessed by corrected ΔT-wave peak to T-wave end interval increased significantly for CAP + O(3) (0.17 ± 0.03, p < 0.0001) exposure only, remaining significant when factoring FA (CAP + O(3) - FA) as control (0.11 ± 0.04, p = 0.013). The influence on repolarization was further verified by a significant increase in ΔQT dispersion (for CAP + O(3) compared with FA (5.7 ± 1.4, p = 0.0002). When the low-frequency to high-frequency ratio of heart rate variability (a conventional representation of sympathetic-parasympathetic balances) was included as a covariate, the effect estimate was positive for both corrected ΔT-wave peak to T-wave end interval (p = 0.002) and ΔQT dispersion (p = 0.038). When the high-frequency component (parasympathetic heart rate modulation) was included as a covariate with corrected ΔT-wave peak to T-wave end interval, the effect estimate for high frequency was inverse (p = 0.02). CONCLUSIONS CAP + O(3) exposure alters dispersion of ventricular repolarization in part by increasing sympathetic and decreasing parasympathetic heart rate modulation. Detection of changes in repolarization parameters, even in this small cohort of healthy individuals, suggests an underappreciated role for air pollutants in urban arrhythmogenesis.
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Salama G, Akar FG. Deciphering Arrhythmia Mechanisms - Tools of the Trade. Card Electrophysiol Clin 2011; 3:11-21. [PMID: 21572551 PMCID: PMC3093299 DOI: 10.1016/j.ccep.2010.10.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Pathophysiological remodeling of cardiac function occurs at multiple levels, spanning the spectrum from molecular and sub-cellular changes to those occurring at the organ-system levels. Of key importance to arrhythmias are changes in electrophysiological and calcium handling properties at the tissue level. In this review, we discuss how high-resolution optical action potential and calcium transient imaging has advanced our understanding of basic arrhythmia mechanisms associated with multiple cardiovascular disorders, including the long QT syndrome, heart failure, and ischemia-reperfusion injury. We focus on the role of repolarization gradients (section 1) and calcium mediated triggers (section 2) in the initiation and maintenance of complex arrhythmias in these settings.
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Affiliation(s)
- Guy Salama
- University of Pittsburgh, The Cardiovascular Institute, Pittsburgh, PA, 15261
| | - Fadi G. Akar
- Mount Sinai School of Medicine, New York, NY 10029, Tel: 212-241-9251; FAX: 212-241-4080
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AKAR FADIG. Use-Dependent Modulation of Myocardial Conduction by a New Class of HERG Agonists: Deal Breaker or Cherry on Top? J Cardiovasc Electrophysiol 2010; 21:930-2. [DOI: 10.1111/j.1540-8167.2010.01747.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Sala M, Lazzaretti M, De Vidovich G, Caverzasi E, Barale F, d'Allio G, Brambilla P. Electrophysiological changes of cardiac function during antidepressant treatment. Ther Adv Cardiovasc Dis 2008; 3:29-43. [PMID: 19124389 DOI: 10.1177/1753944708096282] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Some antidepressant agents can cause electrophysiological changes of cardiac function leading to ventricular arrhythmias and sudden death. However, antidepressants have also protective effects on the heart through their capacity to modulate cardiac autonomic-mediated physiological responses. Heart rate variability and QTc length are two strictly linked parameters that allow us to appreciate the effects of different drugs on cardiac physiology. Heart rate variability reflects functioning of the autonomic nervous system and possibly also regulation by the limbic system. Autonomic regulation of cardiac activity influences also cardiac repolarization and QT length, both directly and via its effects on heart rate. In this review we present the methodologies adopted to study the effect of antidepressant drugs on QT length and heart rate variability and we summarize data on electrophysiological changes related to antidepressant treatment. Clinical implications for the choice of different antidepressants in different clinical populations are discussed.
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Affiliation(s)
- Michela Sala
- Azienda Sanitaria Locale di Alessandria, Presidio di Casale Monferrato, Department of Mental Health, Italy.
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Zareba KM, Shenkman HJ, Bisognano JD. Predictive Value of Admission Electrocardiography in Patients With Heart Failure. ACTA ACUST UNITED AC 2008; 14:173-9. [DOI: 10.1111/j.1751-7133.2008.07528.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Szydlo K, Wita K, Trusz-Gluza M, Urbanczyk D, Filipecki A, Orszulak W, Tabor Z, Krauze J, Kwasniewski W, Myszor J, Turski M, Kolasa J, Szczogiel J. Impact of left ventricular remodeling on ventricular repolarization and heart rate variability in patients after myocardial infarction treated with primary PCI: prospective 6 months follow-up. Ann Noninvasive Electrocardiol 2008; 13:8-13. [PMID: 18234001 DOI: 10.1111/j.1542-474x.2007.00195.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND The relation between postinfarction left ventricle remodeling (LVR), autonomic nervous system and repolarization process is unclear. Purpose of the study was to assess the influence of LVR on the early (QTpeak) and late (TpeakTend) repolarization periods in patients after myocardial infarction (MI) treated with primary PCI. The day-to-night differences of repolarization parameters and the relation between QT and heart rate variability (HRV) indices, as well left ventricle function were also assessed. METHODS The study cohort of 104 pts was examined 6 months after acute MI. HRV and QT indices (corrected to the heart rate) were obtained from the entire 24-hour Holter recording, daytime and nighttime periods. RESULTS LVR was found in 33 patients (31.7%). The study groups (LVR+ vs LVR-) did not differ in age, the extent of coronary artery lesions and treatment. Left ventricle ejection fraction (LVEF) was lower (38%+/- 11% vs 55%+/- 11%, P < 0.001), both QTc (443 +/- 26 ms vs 420 +/- 20 ms, P < 0.001) and TpeakTendc (98 +/- 11 ms vs 84 +/- 12 ms, P < 0.005) were longer in LVR + patients, with no differences for QTpeakc. Trends toward lower values of time-domain (SDRR, rMSSD) HRV parameters were found in LVR+ pts. Day-to-night difference was observed only for SDRR, more marked in LVR-group. Remarkable relations between delta LVEF (6 months minus baseline), delta LVEDV and TpeakTendc were found, with no such relationships for QTpeakc. CONCLUSIONS The patients with LVR have longer repolarization time, especially the late phase-TpeakTend, which represents transmural dispersion of repolarization. Its prolongation seems to be related to local attributes of myocardium and global function of the left ventricle but unrelated to the autonomic nervous influences. Remodeling with moderate LV systolic dysfunction is associated with insignificant decrease in HRV indices and preserved circadian variability.
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Affiliation(s)
- Krzysztof Szydlo
- I Department of Cardiology, Silesian Medical University, Katowice, Poland.
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Borchert GH, Giggey M, Kolar F, Wong TM, Backx PH, Escriba PV. 2-hydroxyoleic acid affects cardiomyocyte [Ca2+]i transient and contractility in a region-dependent manner. Am J Physiol Heart Circ Physiol 2008; 294:H1948-55. [PMID: 18296566 DOI: 10.1152/ajpheart.01209.2007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Monounsaturated fatty acids such as oleic acid are cardioprotective, modify the physicochemical properties of cardiomyocyte membranes, and affect the electrical stability of these cells by regulating the conductance of ion channels. We have designed a nonhydrolysable oleic acid derivative, 2-hydroxyoleic acid (2-OHOA), which regulates membrane lipid structure and cell signaling, resulting in beneficial cardiovascular effects. We previously demonstrated that 2-OHOA induces PKA activation and PKCalpha translocation to the membrane; both pathways are thought to regulate transient outward K(+) current (I(to)) depending on the stimulus and the species used. This study was designed to investigate the effect of 2-OHOA on isolated cardiomyocytes. We examined the dose- and time-dependent effect of 2-OHOA on cytosolic Ca(2+) concentration ([Ca(2+)](i)) transient and contraction of myocytes isolated from different parts of the rat ventricular myocardium. Although this drug had no effect on [Ca(2+)](i) transient and cell shortening in myocytes isolated from the septum, it increased (up to 95%) [Ca(2+)](i) transient and cell shortening in subpopulations of myocytes from the right and left ventricles. The pattern of the effects of 2-OHOA was similar to that observed following the application of the I(to) blocker 4-aminopyridine, suggesting that the drug may act on this channel. Unlike the effect of 2-OHOA on [Ca(2+)](i) transient and cell shortening, PKCalpha translocation to membranes was not region specific. Thus 2-OHOA-induced effects on [Ca(2+)](i) transients and cell shortening are likely related to reductions in I(to) function, but PKCalpha translocation does not seem to play a role. The present results indicate that 2-OHOA selectively increases myocyte inotropic responsiveness, which could underlie its beneficial cardiovascular effects.
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De Mello WC. Opposite effects of angiotensin II and angiotensin (1-7) on impulse propagation, excitability and cardiac arrhythmias. Is the overexpression of ACE2 arrhythmogenic? ACTA ACUST UNITED AC 2008; 153:7-10. [PMID: 18272241 DOI: 10.1016/j.regpep.2007.12.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2007] [Revised: 12/21/2007] [Accepted: 12/26/2007] [Indexed: 11/24/2022]
Affiliation(s)
- Walmor C De Mello
- Department of Pharmacology, School of Medicine Medical Sciences Campus, UPR, San Juan, PR 00936-5067, USA.
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Hooks DA, Trew ML, Caldwell BJ, Sands GB, LeGrice IJ, Smaill BH. Laminar Arrangement of Ventricular Myocytes Influences Electrical Behavior of the Heart. Circ Res 2007; 101:e103-12. [PMID: 17947797 DOI: 10.1161/circresaha.107.161075] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The response of the heart to electrical shock, electrical propagation in sinus rhythm, and the spatiotemporal dynamics of ventricular fibrillation all depend critically on the electrical anisotropy of cardiac tissue. A long-held view of cardiac electrical anisotropy is that electrical conductivity is greatest along the myocyte axis allowing most rapid propagation of electrical activation in this direction, and that conductivity is isotropic transverse to the myocyte axis supporting a slower uniform spread of activation in this plane. In this context, knowledge of conductivity in two directions, parallel and transverse to the myofiber axis, is sufficient to characterize the electrical action of the heart. Here we present new experimental data that challenge this view. We have used a novel combination of intramural electrical mapping, and experiment-specific computer modeling, to demonstrate that left ventricular myocardium has unique bulk conductivities associated with three microstructurally-defined axes. We show that voltage fields induced by intramural current injection are influenced by not only myofiber direction, but also the transmural arrangement of muscle layers or myolaminae. Computer models of these experiments, in which measured 3D tissue structure was reconstructed in-silico, best matched recorded voltages with conductivities in the myofiber direction, and parallel and normal to myolaminae, set in the ratio 4:2:1, respectively. These findings redefine cardiac tissue as an electrically orthotropic substrate and enhance our understanding of how external shocks may act to successfully reset the fibrillating heart into a uniform electrical state. More generally, the mechanisms governing the destabilization of coordinated electrical propagation into ventricular arrhythmia need to be evaluated in the light of this discovery.
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Affiliation(s)
- Darren A. Hooks
- From the Bioengineering Institute (D.A.H., M.L.T., B.J.C., G.B.S., I.J.L., B.H.S.), and the Department of Physiology, School of Medicine (I.J.L., B.H.S.), University of Auckland, New Zealand
| | - Mark L. Trew
- From the Bioengineering Institute (D.A.H., M.L.T., B.J.C., G.B.S., I.J.L., B.H.S.), and the Department of Physiology, School of Medicine (I.J.L., B.H.S.), University of Auckland, New Zealand
| | - Bryan J. Caldwell
- From the Bioengineering Institute (D.A.H., M.L.T., B.J.C., G.B.S., I.J.L., B.H.S.), and the Department of Physiology, School of Medicine (I.J.L., B.H.S.), University of Auckland, New Zealand
| | - Gregory B. Sands
- From the Bioengineering Institute (D.A.H., M.L.T., B.J.C., G.B.S., I.J.L., B.H.S.), and the Department of Physiology, School of Medicine (I.J.L., B.H.S.), University of Auckland, New Zealand
| | - Ian J. LeGrice
- From the Bioengineering Institute (D.A.H., M.L.T., B.J.C., G.B.S., I.J.L., B.H.S.), and the Department of Physiology, School of Medicine (I.J.L., B.H.S.), University of Auckland, New Zealand
| | - Bruce H. Smaill
- From the Bioengineering Institute (D.A.H., M.L.T., B.J.C., G.B.S., I.J.L., B.H.S.), and the Department of Physiology, School of Medicine (I.J.L., B.H.S.), University of Auckland, New Zealand
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Meyer T, Sartipy P, Blind F, Leisgen C, Guenther E. New cell models and assays in cardiac safety profiling. Expert Opin Drug Metab Toxicol 2007. [DOI: 10.1517/17425255.3.4.507] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Grandi E, Puglisi JL, Wagner S, Maier LS, Severi S, Bers DM. Simulation of Ca-calmodulin-dependent protein kinase II on rabbit ventricular myocyte ion currents and action potentials. Biophys J 2007; 93:3835-47. [PMID: 17704163 PMCID: PMC2084250 DOI: 10.1529/biophysj.107.114868] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Ca-calmodulin-dependent protein kinase II (CaMKII) was recently shown to alter Na(+) channel gating and recapitulate a human Na(+) channel genetic mutation that causes an unusual combined arrhythmogenic phenotype in patients: simultaneous long QT syndrome and Brugada syndrome. CaMKII is upregulated in heart failure where arrhythmias are common, and CaMKII inhibition can reduce arrhythmias. Thus, CaMKII-dependent channel modulation may contribute to acquired arrhythmic disease. We developed a Markovian Na(+) channel model including CaMKII-dependent changes, and incorporated it into a comprehensive myocyte action potential (AP) model with Na(+) and Ca(2+) transport. CaMKII shifts Na(+) current (I(Na)) availability to more negative voltage, enhances intermediate inactivation, and slows recovery from inactivation (all loss-of-function effects), but also enhances late noninactivating I(Na) (gain of function). At slow heart rates, with long diastolic time for I(Na) recovery, late I(Na) is the predominant effect, leading to AP prolongation (long QT syndrome). At fast heart rates, where recovery time is limited and APs are shorter, there is little effect on AP duration, but reduced availability decreases I(Na), AP upstroke velocity, and conduction (Brugada syndrome). CaMKII also increases cardiac Ca(2+) and K(+) currents (I(Ca) and I(to)), complicating CaMKII-dependent AP changes. Incorporating I(Ca) and I(to) effects individually prolongs and shortens AP duration. Combining I(Na), I(Ca), and I(to) effects results in shortening of AP duration with CaMKII. With transmural heterogeneity of I(to) and I(to) downregulation in heart failure, CaMKII may accentuate dispersion of repolarization. This provides a useful initial framework to consider pathways by which CaMKII may contribute to arrhythmogenesis.
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Affiliation(s)
- Eleonora Grandi
- Biomedical Engineering Laboratory, Department of Electronics, Computer Science and Systems, University of Bologna, Bologna, Italy
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Ashikaga H, Coppola BA, Hopenfeld B, Leifer ES, McVeigh ER, Omens JH. Transmural dispersion of myofiber mechanics: implications for electrical heterogeneity in vivo. J Am Coll Cardiol 2007; 49:909-16. [PMID: 17320750 PMCID: PMC2572715 DOI: 10.1016/j.jacc.2006.07.074] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2006] [Revised: 07/05/2006] [Accepted: 07/10/2006] [Indexed: 10/23/2022]
Abstract
OBJECTIVES We investigated whether transmural mechanics could yield insight into the transmural electrical sequence. BACKGROUND Although the concept of transmural dispersion of repolarization has helped explain a variety of arrhythmias, its presence in vivo is still disputable. METHODS We studied the time course of transmural myofiber mechanics in the anterior left ventricle of normal canines in vivo (n = 14) using transmural bead markers under biplane cineradiography. In 4 of these animals, plunge electrodes were placed in the myocardial tissue within the bead set to measure transmural electrical sequence. RESULTS The onset of myofiber shortening was earliest at endocardial layers and progressively delayed toward epicardial layers (p < 0.001), resulting in transmural dispersion of myofiber shortening of 39 ms. The onset of myofiber relaxation was earliest at epicardial layers and most delayed at subendocardial layers (p = 0.004), resulting in transmural dispersion of myofiber relaxation of 83 ms. There was no significant transmural gradient in electrical repolarization (p = NS). CONCLUSIONS Despite lack of evidence of significant transmural gradient in electrical repolarization in vivo, there is transmural dispersion of myofiber relaxation as well as shortening.
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Affiliation(s)
- Hiroshi Ashikaga
- Department of Medicine and Bioengineering, University of California, San Diego, La Jolla, California, USA.
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Nader A, Massumi A, Cheng J, Razavi M. Inherited arrhythmic disorders: long QT and Brugada syndromes. Tex Heart Inst J 2007; 34:67-75. [PMID: 17420796 PMCID: PMC1847921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Inherited arrhythmic disorders comprise a group of syndromes with unique genetic abnormalities and presentations but with very similar clinical outcomes and complications, the most terrifying of which are life-threatening arrhythmias and sudden cardiac death. Advances in molecular biology have enabled us to define and pinpoint many such disorders, which were previously labeled as idiopathic, to specific genes on various chromosomes. The current trend in the management of these potentially deadly disorders is to use pharmacotherapy (antiarrhythmic agents) and defibrillators for the prevention of sudden death; however, targeted therapy at a molecular level appears to be the path of the future. Herein, we review long QT and Brugada syndromes and focus on the genetics, pathophysiology, and clinical manifestations of these inherited arrhythmogenic disorders that affect patients with structurally normal hearts.
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Affiliation(s)
- Amirali Nader
- Department of Cardiac Electrophysiology, Texas Heart Institute at St. Luke's Episcopal Hospital, Houston, Texas 77030, USA
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Abstract
Doctor Wilde, presenting on behalf of himself and Dr Eckardt, discussed the role of invasive and noninvasive tests for risk stratification of Brugada syndrome. Doctor Hiraoka, presenting on behalf of Y. Yokoyama, M. Takagi, N. Aihara, K. Aonuma, and the Japan Idiopathic Ventricular Fibrillation Study Investigators, further discussed the diagnostic criteria for the Brugada syndrome. Doctor Antzelevitch examined the hypothesis that amplification of spatial dispersion of repolarization in the form of transmural dispersion of repolarization underlies the development of life-threatening ventricular arrhythmias associated with inherited ion channelopathies including the long QT, short QT, and Brugada syndromes. Doctor Corrado discussed the relationship between channelopathies and heart muscle diseases.
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Stambler BS. Tachycardia-induced ventricular electrical remodeling: A perspective on unresolved experimental mechanisms and clinical implications. Heart Rhythm 2006; 3:1378-81. [PMID: 17074649 DOI: 10.1016/j.hrthm.2006.06.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2006] [Indexed: 11/23/2022]
Affiliation(s)
- Bruce S Stambler
- Division of Cardiology, Department of Medicine, Case Western Reserve University, School of Medicine, Cleveland, Ohio 44106, USA.
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