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El-Azrak M, Darar C, Boutaybi M, El Ouafi N, Bazid Z. Sudden Cardiac Death Risk Stratification of the Early Repolarization Syndrome: An Updated Review of the Literature. Curr Cardiol Rep 2023; 25:203-212. [PMID: 36763218 DOI: 10.1007/s11886-023-01842-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/24/2023] [Indexed: 02/11/2023]
Abstract
PURPOSE OF REVIEW Early repolarization syndrome (ERS), once thought to be innocuous, has now been shown to be responsible for ventricular arrythmias and sudden cardiac death occurrence. This review will help the clinician to identify the patients who are most at risk for arrhythmias, so that they can adopt a preventive or secondary treatment approach, either of which is still poorly defined. RECENT FINDINGS Patients at high risk are found to be particularly young men, with a personal or family history of syncope or sudden death, who have an inferolateral ER on the electrocardiogram, more elevated J-point, longer J-wave duration and wider J angle, a horizontal or descending ST segment, lower T/R ratio, and small and/or inverted waves. The association with a structural heart disease or another channelopathy potentiates this arrhythmic risk. Taken together, these parameters allow prediction of the malignancy of ER pattern with a certain reliability. Further research is however needed to develop concrete risk stratification algorithms and the therapeutic strategies taken in function of it.
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Affiliation(s)
- Mohammed El-Azrak
- Department of Cardiology, Mohammed VI University Hospital, Oujda, Morocco.
| | - Charmake Darar
- Department of Cardiology, Mohammed VI University Hospital, Oujda, Morocco
| | - Mohammed Boutaybi
- Department of Cardiology, Mohammed VI University Hospital, Oujda, Morocco
| | - Noha El Ouafi
- Department of Cardiology, Mohammed VI University Hospital, Oujda, Morocco.,Epidemiological Laboratory of Clinical Research and Public Health, Faculty of Medicine and Pharmacy of Oujda, Mohammed First University, Oujda, Morocco
| | - Zakaria Bazid
- Department of Cardiology, Mohammed VI University Hospital, Oujda, Morocco
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2
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Wang G, Zhao N, Zhong S, Wang H. Association of early repolarization pattern and ventricular fibrillation in patients with vasospastic angina: A systematic review and meta-analysis. Clin Cardiol 2022; 45:461-473. [PMID: 35253242 PMCID: PMC9045077 DOI: 10.1002/clc.23804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 02/09/2022] [Accepted: 02/17/2022] [Indexed: 11/30/2022] Open
Abstract
Background An early repolarization (ER) pattern is a risk factor for ventricular fibrillation (VF) in patients with vasospastic angina (VSA) caused by a coronary artery spasm. However, its detailed characteristics and prognostic value for VF remain unclear. Thus, we investigated the relationship between ER and VF in patients with VSA. Hypothesis The ER pattern is associated with VF in patients with VSA. Methods In this systematic review and meta‐analysis, we searched PubMed, Embase, Cochrane Library, and Web of Science databases for eligible studies published between January 2011 and December 2020; 8 studies with 1761 patients were included in the final analysis. Results The ER pattern significantly predicted adverse cardiovascular events (ACEs) and VF (odds ratio [OR] = 5.13, 95% confidence interval [95% CI]: 3.16–8.35, p < .00001 and OR = 5.20, 95% CI: 3.05–8.87, p < .00001). The presence of ER in the inferior leads increased the VF risk (OR = 7.80, 95% CI: 4.04–15.05, p < .00001), regardless of the J‐point morphology or type of ST‐segment elevation in the ER pattern. A horizontal/descending ST‐segment elevation was significantly associated with VF in patients with or without an ER pattern during a coronary spasm (OR = 2.28, 95% CI: 1.07–4.88, p = .03). However, obstructive coronary artery disease was unrelated to the ER pattern (OR = 0.82, 95% CI: 0.27–2.53, p = .73). Conclusions An ER pattern is significantly associated with an increased risk of ACE in patients with VSA. An inferior ER pattern with horizontal/descending ST‐segment elevation confers the highest risk for VF during VSA onset. Nevertheless, the ER pattern is not associated with obstructive coronary artery disease.
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Affiliation(s)
- Guangqiang Wang
- Department of Cardiology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, China
| | - Na Zhao
- Department of Rheumatology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, China
| | - Shu Zhong
- Department of Cardiology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, China
| | - Hua Wang
- Department of Cardiology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, China
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Zhang L, Dong S, Zhao W, Li J, Cui L, Han Y, Chu Y. Relationship Between an Ischaemic J Wave Pattern and Ventricular Fibrillation in ST-Elevation Myocardial Infarction Patients. Int J Gen Med 2021; 14:8725-8735. [PMID: 34849013 PMCID: PMC8627274 DOI: 10.2147/ijgm.s337638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 11/05/2021] [Indexed: 12/02/2022] Open
Abstract
Background This study determined the ischaemic J wave pattern associated with ventricular fibrillation (VF). Methods A total of 262 patients diagnosed with ST-elevation myocardial infarction (STEMI) were recruited from October 2017 to September 2020. All data were collected and analysed, including baseline characteristics, electrocardiogram (ECG), coronary angiography (CAG), and examination outcomes. Results There were 193 STEMI patients with J wave elevation but without an ischaemic J wave (NJ group) and 69 patients with an ischaemic J wave; the latter were then subgrouped into early repolarization pattern (ERP; n=62) and Brugada pattern groups (BrP [anteroseptal ERP]; n=7). Univariate and multivariate logistic regression analyses were used to clarify high-risk factors and characteristics of ischaemic J waves. Multivariate logistic regression analysis revealed that an ischaemic J wave (odds ratio [OR], 9.708; 95% CI, 2.570–36.664; P=0.01) independently predicted VF. In the subgroup analysis, BrP (OR, 31.214; 95% CI, 3.949–246.742; P=0.001), slur morphology of the ERP (OR, 8.15; 95% CI, 1.563–42.558; P<0.05), and the number of leads with an ischaemic J wave > 3 (OR, 16.174; 95% CI, 3.064–85.375; P=0.001) were significantly associated with VF occurrence after adjusting for multiple variables. Conclusion An ischaemic J wave is an independent risk factor for VF in STEMI patients. BrP, slur morphology, and > 3 leads with an ischaemic J wave could increase the incidence of VF.
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Affiliation(s)
- Luyao Zhang
- Department of Cardiology, Henan Provincial People's Hospital, Zhengzhou, Henan Province, 450003, People's Republic of China
| | - Shujuan Dong
- Department of Cardiology, Henan Provincial People's Hospital, Zhengzhou, Henan Province, 450003, People's Republic of China
| | - Wenbo Zhao
- Department of Cardiology, Henan Provincial People's Hospital, Zhengzhou, Henan Province, 450003, People's Republic of China
| | - Jingchao Li
- Department of Cardiology, Henan Provincial People's Hospital, Zhengzhou, Henan Province, 450003, People's Republic of China
| | - Luqian Cui
- Department of Cardiology, Henan Provincial People's Hospital, Zhengzhou, Henan Province, 450003, People's Republic of China
| | - Yongmei Han
- Department of Cardiology, Henan Provincial People's Hospital, Zhengzhou, Henan Province, 450003, People's Republic of China
| | - Yingjie Chu
- Department of Cardiology, Henan Provincial People's Hospital, Zhengzhou, Henan Province, 450003, People's Republic of China
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Zhu T, Lei M, Wang Z, Zhang R, Zhang Y, Jin W, Yu C, Huang CLH, Liu D, Zheng W, Liu Y, Quan X, Kong L, Liang S, Zhang X. A Comparative Study of Systolic and Diastolic Mechanical Synchrony in Canine, Primate, and Healthy and Failing Human Hearts. Front Cardiovasc Med 2021; 8:750067. [PMID: 34778406 PMCID: PMC8581184 DOI: 10.3389/fcvm.2021.750067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 09/28/2021] [Indexed: 11/13/2022] Open
Abstract
Aim: Mechanical dyssynchrony (MD) is associated with heart failure (HF) and may be prognostically important in cardiac resynchronization therapy (CRT). Yet, little is known about its patterns in healthy or diseased hearts. We here investigate and compare systolic and diastolic MD in both right (RV) and left ventricles (LV) of canine, primate and healthy and failing human hearts. Methods and Results: RV and LV mechanical function were examined by pulse-wave Doppler in 15 beagle dogs, 59 rhesus monkeys, 100 healthy human subjects and 39 heart failure (HF) patients. This measured RV and LV pre-ejection periods (RVPEP and LVPEP) and diastolic opening times (Q-TVE and Q-MVE). The occurrence of right (RVMDs) and left ventricular systolic mechanical delay (LVMDs) was assessed by comparing RVPEP and LVPEP values. That of right (RVMDd) and left ventricular diastolic mechanical delay (LVMDd) was assessed from the corresponding diastolic opening times (Q-TVE and Q-MVE). These situations were quantified by values of interventricular systolic (IVMDs) and diastolic mechanical delays (IVMDd), represented as positive if the relevant RV mechanical events preceded those in the LV. Healthy hearts in all species examined showed greater LV than RV delay times and therefore positive IVMDs and IVMDd. In contrast a greater proportion of the HF patients showed both markedly increased IVMDs and negative IVMDd, with diastolic mechanical asynchrony negatively correlated with LVEF. Conclusion: The present IVMDs and IVMDd findings have potential clinical implications particularly for personalized setting of parameter values in CRT in individual patients to achieve effective treatment of HF.
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Affiliation(s)
- Tiangang Zhu
- Department of Cardiology, Peking University People's Hospital, Beijing, China
| | - Ming Lei
- Medical Sciences Division, Department of Pharmacology, University of Oxford, Oxford, United Kingdom.,Key Laboratory of Medical Electrophysiology of Ministry of Education, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China
| | - Zhilong Wang
- Department of Cardiology, Peking University People's Hospital, Beijing, China.,Department of Cardiology, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, China
| | - Rongli Zhang
- Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, China.,Case Cardiovascular Research Institute, Institute for Molecular Transformative Medicine, Case Western Reserve University, Cleveland, OH, United States
| | - Yan Zhang
- Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, China.,Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking University, Beijing, China
| | - Wenying Jin
- Department of Cardiology, Peking University People's Hospital, Beijing, China
| | - Chao Yu
- Department of Cardiology, Peking University People's Hospital, Beijing, China
| | - Christopher L-H Huang
- Key Laboratory of Medical Electrophysiology of Ministry of Education, Institute of Cardiovascular Research, Southwest Medical University, Luzhou, China.,Physiological Laboratory, University of Cambridge, Cambridge, United Kingdom.,Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Dongyue Liu
- Department of Cardiology, Peking University People's Hospital, Beijing, China
| | - Wen Zheng
- Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, China.,Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking University, Beijing, China
| | - Yuli Liu
- Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, China
| | - Xin Quan
- Department of Cardiology, National Center for Cardiovascular Diseases, Fuwai Hospital, Beijing, China
| | - Lingyun Kong
- Beijing Tsinghua Changgung Hospital, Beijing, China
| | - Siying Liang
- Department of Cardiology, Peking University People's Hospital, Beijing, China
| | - Xiuqin Zhang
- Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, China.,Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Peking University, Beijing, China
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Xu S, Yang L, Hong D, Chen L, Wang X. The Prognostic Value of Early Repolarization Pattern for the Ventricular Tachyarrhythmias of Acute Myocardial Infarction Patients: A Meta-Analysis. Cardiology 2019; 144:69-75. [PMID: 31434097 DOI: 10.1159/000501474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Accepted: 06/08/2019] [Indexed: 02/05/2023]
Abstract
Several studies have indicated that early repolarization (ER) is a risk factor for ventricular tachyarrhythmias (VTAs) in acute myocardial infarction (AMI) patients. The prognostic values of ER detail characteristics except J-point morphology, and inferior leads ER location for VTAs are still unclear. We searched PubMed, Embase, and the Cochrane Library for eligible studies up to March 4, 2019. Studies to investigate the relationship between ER and the incidence of VTAs in AMI patients were extracted. A total of 10 studies with 2,672 participants were included in the analysis. ER significantly predicted the incidence of VTAs (odds ratio [OR] 3.62, 95% confidence intervals [CI] 2.77-4.73), regardless of the type of AMI. The presence of ER before AMI (OR 5.58, 95% CI 3.41 to 9.12) and after AMI (OR 3.02, 95% CI 2.19-4.15) increased the risk of VTAs. The prognostic value of ER for VTAs in the long follow-up (≥30 days) (OR 2.39, 95% CI 1.59-3.59) fell by half compared to the short follow-up duration (<30 days) (OR 4.97, 95% CI 3.48-7.09). Patients with ER displayed a higher risk of developing ventricular fibrillation (VF) (OR 6.94, 95% CI 3.87-12.43) than those without ER. However, neither J-point elevation with OR = 2.48 nor lateral leads' ER location with OR = 3.83 remarkably increased the risk of VTAs in patients with AMI. ER is significantly associated with increasing risk of VTAs, particularly VF, in AMI patients. This relationship is weaker in the 30-day follow-up and is not reinforced by J-point elevation and lateral leads' ER location.
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Affiliation(s)
- Shangbo Xu
- Department of Cardiology, First Affiliated Hospital of Shantou University Medical College, Shantou, China
- Shantou University Medical College, Shantou, China
| | - Lihua Yang
- Department of Cardiology, First Affiliated Hospital of Shantou University Medical College, Shantou, China
| | - Danhua Hong
- Department of Cardiology, First Affiliated Hospital of Shantou University Medical College, Shantou, China
| | - Lan Chen
- Department of Cardiology, First Affiliated Hospital of Shantou University Medical College, Shantou, China
| | - Xin Wang
- Department of Cardiology, First Affiliated Hospital of Shantou University Medical College, Shantou, China,
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Abstract
Early repolarization, Brugada syndrome, and pathologic J waves have been described for decades, but only recently experimental and clinical data have allowed reconciliation of Brugada and Early Repolarization under the common definition of J-wave syndromes. The concept was derived from studies showing, in both conditions, the presence of transmural dispersion of repolarization, localized conduction abnormalities, and abnormal transition between QRS and ST segment on electrocardiogram. Although several clinical studies have addressed the clinical presentation and epidemiology of J-wave syndromes, relevant knowledge gaps exist. Incomplete pathophysiologic understanding and uncertain electrocardiographic definitions limit effective risk stratification. Here, we review the current knowledge and recommendations for diagnosis and clinical management of these arrhythmogenic disorders.
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Affiliation(s)
- Silvia G Priori
- Molecular Cardiology, ICS Maugeri, IRCCS, Pavia, Italy; Department of Molecular Medicine, University of Pavia, Pavia, Italy.
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Szabó IA, Fárr A, Kocsis I, Máthé L, Szilágyi L, Frigy A. The Early Repolarization ECG Pattern – An Update. ACTA MEDICA MARISIENSIS 2017. [DOI: 10.1515/amma-2017-0032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
Early repolarization pattern (ERP), a form of J-wave syndromes, was considered long time a benign ECG phenomenon. However, recent data confirmed that certain phenotypes of ERP are related to an increased risk of sudden cardiac death (idiopathic ventricular fibrillation). Our paper gives a short and practical update regarding the main issues related to ERP: epidemiological data, molecular and electrophysiological background, clinical significance and risk stratification. At the end, the future directions of research and clinical management related to ERP are presented.
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Affiliation(s)
- István Adorján Szabó
- Department of Cardiology, Clinical County Hospital Mures , Tîrgu Mureş , Romania
| | - Annamária Fárr
- Department of Physiopathology , University of Medicine and Pharmacy of Tîrgu Mureş , Romania
| | - Ildikó Kocsis
- Department of Cardiology, Clinical County Hospital Mures , Tîrgu Mureş , Romania
| | - Lehel Máthé
- Department of Internal Medicine VII , University of Medicine and Pharmacy of Tîrgu Mureş , Romania
| | | | - Atilla Frigy
- Department of Internal Medicine IV , University of Medicine and Pharmacy of Tîrgu Mureş , Romania
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Mazzanti A, Underwood K, Nevelev D, Kofman S, Priori SG. The new kids on the block of arrhythmogenic disorders: Short QT syndrome and early repolarization. J Cardiovasc Electrophysiol 2017; 28:1226-1236. [PMID: 28569435 DOI: 10.1111/jce.13265] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 05/10/2017] [Accepted: 05/25/2017] [Indexed: 12/20/2022]
Abstract
Short QT syndrome (SQTS) is one of the rarest inheritable cardiac channelopathies, characterized by an accelerated cardiac repolarization, which is also the substrate for the development of life-threatening ventricular arrhythmias. Up to this date, fewer than 200 SQTS cases have been reported in the literature worldwide. Patients with SQTS may experience a cardiac arrest as early as in the neonatal period or as late as 80 years old. The cumulative probability of experiencing a cardiac arrest by the fifth decade of life approaches 40%, highlighting the importance of early recognition and management. SQTS is an autosomal dominant disease with five identified causative genes, including three that encode for potassium channels (KCNH2, KCNQ1, and KCNJ2) and two that encode for subunits of the L-type calcium channels (CACNA1C and CACNB2). The term "early repolarization" (ER) has long been used to refer to a heterogeneous group of specific QRS-T junction patterns that are commonly found on the electrocardiograms of young healthy subjects. In the last decade, it has been suggested that in some individuals, the presence of ER may be associated with an increased risk of sudden cardiac death, and thus the term "early repolarization syndrome" (ERS) has progressively entered into use. Up to this point, however, whether ER constitutes a true primary arrhythmic disorder or whether it is simply a predisposing substrate that facilitates arrhythmias in the presence of other triggers remains an unresolved issue. In this review paper, we aim to integrate the current literature on SQTS and ERS. For each, we will describe the key steps that first led to the identification of the syndrome before moving into a discussion of our current understanding of each entity, including the epidemiology, genetics, diagnosis, clinical manifestations, and management.
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Affiliation(s)
| | | | | | - Shanna Kofman
- Molecular Cardiology, IRCCS ICS Maugeri, Pavia, Italy
| | - Silvia G Priori
- Molecular Cardiology, IRCCS ICS Maugeri, Pavia, Italy.,Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
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Eranti A, Aro AL, Kenttä T, Holkeri A, Tikkanen JT, Junttila MJ, Huikuri HV. 12-Lead electrocardiogram as a predictor of sudden cardiac death: from epidemiology to clinical practice. SCAND CARDIOVASC J 2016; 50:253-259. [PMID: 27454252 DOI: 10.1080/14017431.2016.1215520] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Sudden cardiac death (SCD) causes a high burden of premature deaths in the population affecting subjects of all ages. The identification of subjects at high risk for SCD is of great importance as the prevention of many of these events would be possible with the treatment of underlying cardiac diseases and the use of implantable cardioverter-defibrillators (ICD). However, the current selection of patients for ICD therapy is based solely on left ventricular ejection fraction, and thus a substantial portion of patients at high risk does not qualify for the therapy. Role of the standard electrocardiogram (ECG) in SCD risk stratification has been under active research during the last decade and multiple abnormalities of depolarization and repolarization on the ECG associated with an increased risk of SCD have been identified. In this review, we describe the basic pathophysiological principles behind these changes. We also review the current knowledge of the prognostic significance of ECG predictors of SCD in the general population, and in patients with coronary heart disease (CHD), heart failure, cardiomyopathies, and in inheritable arrhythmia syndromes. Also, insights into the novel digital ECG signal processing techniques are provided.
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Affiliation(s)
- Antti Eranti
- a Department of Internal Medicine , Päijät-Häme Central Hospital , Lahti , Finland
| | - Aapo L Aro
- b Division of Cardiology , Heart and Lung Center, Helsinki University Central Hospital , Helsinki , Finland
| | - Tuomas Kenttä
- c Medical Research Center Oulu, Oulu University Hospital and University of Oulu , Oulu , Finland
| | - Arttu Holkeri
- b Division of Cardiology , Heart and Lung Center, Helsinki University Central Hospital , Helsinki , Finland
| | - Jani T Tikkanen
- c Medical Research Center Oulu, Oulu University Hospital and University of Oulu , Oulu , Finland
| | - M Juhani Junttila
- c Medical Research Center Oulu, Oulu University Hospital and University of Oulu , Oulu , Finland
| | - Heikki V Huikuri
- c Medical Research Center Oulu, Oulu University Hospital and University of Oulu , Oulu , Finland
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YiXin-Shu, a ShengMai-San-based traditional Chinese medicine formula, attenuates myocardial ischemia/reperfusion injury by suppressing mitochondrial mediated apoptosis and upregulating liver-X-receptor α. Sci Rep 2016; 6:23025. [PMID: 26964694 PMCID: PMC4786861 DOI: 10.1038/srep23025] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 02/25/2016] [Indexed: 12/14/2022] Open
Abstract
Positive evidence from clinical trials has fueled growing acceptance of traditional Chinese medicine (TCM) for the treatment of cardiac diseases; however, little is known about the underlying mechanisms. Here, we investigated the nature and underlying mechanisms of the effects of YiXin-Shu (YXS), an antioxidant-enriched TCM formula, on myocardial ischemia/reperfusion (MI/R) injury. YXS pretreatment significantly reduced infarct size and improved viable myocardium metabolism and cardiac function in hypercholesterolemic mice. Mechanistically, YXS attenuated myocardial apoptosis by inhibiting the mitochondrial mediated apoptosis pathway (as reflected by inhibition of mitochondrial swelling, cytochrome c release and caspase-9 activity, and normalization of Bcl-2 and Bax levels) without altering the death receptor and endoplasmic reticulum-stress death pathways. Moreover, YXS reduced oxidative/nitrative stress (as reflected by decreased superoxide and nitrotyrosine content and normalized pro- and anti-oxidant enzyme levels). Interestingly, YXS upregulated endogenous nuclear receptors including LXRα, PPARα, PPARβ and ERα, and in-vivo knockdown of cardiac-specific LXRα significantly blunted the cardio-protective effects of YXS. Collectively, these data show that YXS is effective in mitigating MI/R injury by suppressing mitochondrial mediated apoptosis and oxidative stress and by upregulating LXRα, thereby providing a rationale for future clinical trials and clinical applications.
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