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Takahara A, Kawakami S, Aimoto M, Nagasawa Y. Torsadogenic Potential of HCN Channel Blocker Ivabradine Assessed in the Rabbit Proarrhythmia Model. Biol Pharm Bull 2021; 44:1796-1799. [PMID: 34719656 DOI: 10.1248/bpb.b21-00605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Torsadogenic effects of ivabradine, an inhibitor of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, were assessed in an in vivo proarrhythmia model of acute atrioventricular block rabbit. Ivabradine at 0.01, 0.1, and 1 mg/kg was intravenously administered to isoflurane-anesthetized rabbits (n = 5) in the stable idioventricular rhythm. Ivabradine at 0.01 and 0.1 mg/kg hardly affected the atrial and ventricular automaticity, QT interval, or the monophasic action potential duration of the ventricle. Additionally administred ivabradine at 1 mg/kg decreased the atrial and ventricular rate significantly but increased the QT interval and duration of the monophasic action potential. Meanwhile, torsade de pointes arrhythmias were detected in 1 out of 5 animals and in 2 out of 5 animals after the administration of 0.1 and 1 mg/kg, respectively. Importantly, torsade de pointes arrhythmias could be observed only in 2 rabbits showing more potent suppressive effects on ventricular automaticity. These results suggest that the torsadogenic potential of ivabradine may become evident when its expected bradycardic action appears more excessively.
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Affiliation(s)
- Akira Takahara
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University
| | - Satoshi Kawakami
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University
| | - Megumi Aimoto
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University
| | - Yoshinobu Nagasawa
- Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University
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2
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Oknińska M, Paterek A, Zambrowska Z, Mackiewicz U, Mączewski M. Effect of Ivabradine on Cardiac Ventricular Arrhythmias: Friend or Foe? J Clin Med 2021; 10:4732. [PMID: 34682854 PMCID: PMC8537674 DOI: 10.3390/jcm10204732] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/24/2021] [Accepted: 10/08/2021] [Indexed: 12/12/2022] Open
Abstract
Life-threatening ventricular arrhythmias, such as ventricular tachycardia and ventricular fibrillation remain an ongoing clinical problem and their prevention and treatment require optimization. Conventional antiarrhythmic drugs are associated with significant proarrhythmic effects that often outweigh their benefits. Another option, the implantable cardioverter defibrillator, though clearly the primary therapy for patients at high risk of ventricular arrhythmias, is costly, invasive, and requires regular monitoring. Thus there is a clear need for new antiarrhythmic treatment strategies. Ivabradine, a heartrate-reducing agent, an inhibitor of HCN channels, may be one of such options. In this review we discuss emerging data from experimental studies that indicate new mechanism of action of this drug and further areas of investigation and potential use of ivabradine as an antiarrhythmic agent. However, clinical evidence is limited, and the jury is still out on effects of ivabradine on cardiac ventricular arrhythmias in the clinical setting.
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Affiliation(s)
| | | | | | | | - Michał Mączewski
- Centre of Postgraduate Medical Education, Department of Clinical Physiology, ul. Marymoncka 99/103, 01-813 Warsaw, Poland; (M.O.); (A.P.); (Z.Z.); (U.M.)
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3
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Beneficial Effects of Ivabradine on Post-Resuscitation Myocardial Dysfunction in a Porcine Model of Cardiac Arrest. Shock 2021; 53:630-636. [PMID: 31274829 PMCID: PMC7161719 DOI: 10.1097/shk.0000000000001403] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Background: Ivabradine selectively inhibits the If current, reducing the heart rate and protecting against myocardial ischemia/reperfusion injury. We investigated the effects of ivabradine on post-resuscitation myocardial function in a porcine model of cardiopulmonary resuscitation. Methods and Results: Ventricular fibrillation was induced and untreated for 8 min while defibrillation was attempted after 6 min of cardiopulmonary resuscitation in anesthetized domestic swine. Then the animals were randomized into ivabradine and placebo groups (n = 5 each). Ivabradine and saline were administered at the same volume 5 min after Return of Spontaneous Circulation, followed by continuous intravenous infusion at 0.5 mg/kg for 480 min. Hemodynamic parameters were continuously recorded. Myocardial function was assessed by echocardiography at baseline and at 60, 120, 240, 480 min and 24 h after resuscitation. The serum levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) and cardiac troponin I (cTnI) were measured by commercial enzyme-linked immunosorbent assay kits. Animals were killed 24 h after resuscitation, and all myocardial tissue was removed for histopathological analysis. The heart rate was significantly reduced from 1 h after resuscitation in the ivabradine group (all P < 0.05). The post-resuscitation mitral E/A and E/e′ velocity ratios and left ventricular ejection fraction were significantly better in the ivabradine than placebo group (P < 0.05). The serum levels of myocardial injury biomarkers (NT-proBNP, cTnI) and the myocardial biopsy scores were significantly lower in the ivabradine than placebo group (P < 0.05). Neurological deficit scores were lower in the IVA group at PR 24 h (P < 0.05). Conclusions: Ivabradine improved post-resuscitation myocardial dysfunction, myocardial injury, and post-resuscitation cerebral function, and also slowed the heart rate in this porcine model.
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4
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Wongtanasarasin W, Siri-Angkul N, Wittayachamnankul B, Chattipakorn SC, Chattipakorn N. Mitochondrial dysfunction in fatal ventricular arrhythmias. Acta Physiol (Oxf) 2021; 231:e13624. [PMID: 33555138 DOI: 10.1111/apha.13624] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 02/02/2021] [Accepted: 02/04/2021] [Indexed: 02/05/2023]
Abstract
Ventricular fibrillation (VF) and sudden cardiac arrest (SCA) remain some of the most important public health concerns worldwide. For the past 50 years, the recommendation in the Advanced Cardiac Life Support (ACLS) guidelines has been that defibrillation is the only option for shockable cardiac arrest. There is growing evidence to demonstrate that mitochondria play a vital role in the outcome of postresuscitation cardiac function. Although targeting mitochondria to improve resuscitation outcome following cardiac arrest has been proposed for many years, understanding concerning the changes in mitochondria during cardiac arrest, especially in the case of VF, is still limited. In addition, despite new research initiatives and improved medical technology, the overall survival rates of patients with SCA still remain the same. Understanding cardiac mitochondrial alterations during fatal arrhythmias may help to enable the formulation of strategies to improve the outcomes of resuscitation. The attenuation of cardiac mitochondrial dysfunction during VF through pharmacological intervention as well as ischaemic postconditioning could also be a promising target for intervention and inform a new paradigm of treatments. In this review, the existing evidence available from in vitro, ex vivo and in vivo studies regarding the roles of mitochondrial dysfunction during VF is comprehensively summarized and discussed. In addition, the effects of interventions targeting cardiac mitochondria during fatal ventricular arrhythmias are presented. Since there are no clinical reports from studies targeting mitochondria to improve resuscitation outcome available, this review will provide important information to encourage further investigations in a clinical setting.
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Affiliation(s)
- Wachira Wongtanasarasin
- Department of Emergency Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, Thailand
| | - Natthaphat Siri-Angkul
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, Thailand
- Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Borwon Wittayachamnankul
- Department of Emergency Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, Thailand
| | - Siriporn C Chattipakorn
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, Thailand
| | - Nipon Chattipakorn
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
- Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, Thailand
- Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
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5
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Effect of ivabradine on cardiac arrhythmias: Antiarrhythmic or proarrhythmic? Heart Rhythm 2021; 18:1230-1238. [PMID: 33737235 DOI: 10.1016/j.hrthm.2021.03.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 03/09/2021] [Accepted: 03/10/2021] [Indexed: 12/28/2022]
Abstract
Cardiac arrhythmias are a major source of mortality and morbidity. Unfortunately, their treatment remains suboptimal. Major classes of antiarrhythmic drugs pose a significant risk of proarrhythmia, and their side effects often outweigh their benefits. Therefore, implantable devices remain the only truly effective antiarrhythmic therapy, and new strategies of antiarrhythmic treatment are required. Ivabradine is a selective heart rate-reducing agent, an inhibitor of hyperpolarization-activated, cyclic nucleotide-gated (HCN) channels, currently approved for treatment of coronary artery disease and chronic heart failure. In this review, we focus on the clinical and basic science evidence for the antiarrhythmic and proarrhythmic effects of ivabradine. We attempt to dissect the mechanisms behind the effects of ivabradine and indicate the focus of future studies.
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6
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Marciszek M, Paterek A, Oknińska M, Mackiewicz U, Mączewski M. Ivabradine is as effective as metoprolol in the prevention of ventricular arrhythmias in acute non-reperfused myocardial infarction in the rat. Sci Rep 2020; 10:15027. [PMID: 32929098 PMCID: PMC7490414 DOI: 10.1038/s41598-020-71706-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 07/29/2020] [Indexed: 12/29/2022] Open
Abstract
Ventricular arrhythmias are a major source of early mortality in acute myocardial infarction (MI) and remain a major therapeutic challenge. Thus we investigated effects of ivabradine, a presumably specific bradycardic agent versus metoprolol, a β-blocker, at doses offering the same heart rate (HR) reduction, on ventricular arrhythmias in the acute non-reperfused MI in the rat. Immediately after MI induction a single dose of ivabradine/ metoprolol was given. ECG was continuously recorded and ventricular arrhythmias were analyzed. After 6 h epicardial monophasic action potentials (MAPs) were recorded and cardiomyocyte Ca2+ handling was assessed. Both ivabradine and metoprolol reduced HR by 17% and arrhythmic mortality (14% and 19%, respectively, versus 33% in MI, p < 0.05) and ventricular arrhythmias in post-MI rats. Both drugs reduced QTc prolongation and decreased sensitivity of ryanodine receptors in isolated cardiomyocytes, but otherwise had no effect on Ca2+ handling, velocity of conduction or repolarization. We did not find any effects of potential IKr inhibition by ivabradine in this setting. Thus Ivabradine is an equally effective antiarrhythmic agent as metoprolol in early MI in the rat. It could be potentially tested as an alternative antiarrhythmic agent in acute MI when β-blockers are contraindicated.
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Affiliation(s)
- Mariusz Marciszek
- Department of Clinical Physiology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - Aleksandra Paterek
- Department of Clinical Physiology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - Marta Oknińska
- Department of Clinical Physiology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - Urszula Mackiewicz
- Department of Clinical Physiology, Centre of Postgraduate Medical Education, Warsaw, Poland
| | - Michał Mączewski
- Department of Clinical Physiology, Centre of Postgraduate Medical Education, Warsaw, Poland.
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7
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Sattler SM, Skibsbye L, Linz D, Lubberding AF, Tfelt-Hansen J, Jespersen T. Ventricular Arrhythmias in First Acute Myocardial Infarction: Epidemiology, Mechanisms, and Interventions in Large Animal Models. Front Cardiovasc Med 2019; 6:158. [PMID: 31750317 PMCID: PMC6848060 DOI: 10.3389/fcvm.2019.00158] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Accepted: 10/18/2019] [Indexed: 12/22/2022] Open
Abstract
Ventricular arrhythmia and subsequent sudden cardiac death (SCD) due to acute myocardial infarction (AMI) is one of the most frequent causes of death in humans. Lethal ventricular arrhythmias like ventricular fibrillation (VF) prior to hospitalization have been reported to occur in more than 10% of all AMI cases and survival in these patients is poor. Identification of risk factors and mechanisms for VF following AMI as well as implementing new risk stratification models and therapeutic approaches is therefore an important step to reduce mortality in people with high cardiovascular risk. Studying spontaneous VF following AMI in humans is challenging as it often occurs unexpectedly in a low risk subgroup. Large animal models of AMI can help to bridge this knowledge gap and are utilized to investigate occurrence of arrhythmias, involved mechanisms and therapeutic options. Comparable anatomy and physiology allow for this translational approach. Through experimental focus, using state-of-the-art technologies, including refined electrical mapping equipment and novel pharmacological investigations, valuable insights into arrhythmia mechanisms and possible interventions for arrhythmia-induced SCD during the early phase of AMI are now beginning to emerge. This review describes large experimental animal models of AMI with focus on first AMI-associated ventricular arrhythmias. In this context, epidemiology of first AMI, arrhythmogenic mechanisms and various potential therapeutic pharmacological targets will be discussed.
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Affiliation(s)
- Stefan Michael Sattler
- Department of Cardiology, Heart Centre, Copenhagen University Hospital, Copenhagen, Denmark.,Medical Department I, University Hospital Grosshadern, LMU Munich, Munich, Germany
| | - Lasse Skibsbye
- Department of Exploratory Toxicology, H. Lundbeck A/S, Copenhagen, Denmark
| | - Dominik Linz
- Medical Department III, Universitätsklinikum des Saarlandes, Homburg, Germany.,Centre for Heart Rhythm Disorders, South Australian Health and Medical Research Institute, Royal Adelaide Hospital, University of Adelaide, Adelaide, SA, Australia
| | - Anniek Frederike Lubberding
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jacob Tfelt-Hansen
- Department of Cardiology, Heart Centre, Copenhagen University Hospital, Copenhagen, Denmark.,Department of Forensic Medicine, Faculty of Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Jespersen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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8
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Rønning L, Bakkehaug JP, Rødland L, Kildal AB, Myrmel T, How O. Opposite diastolic effects of omecamtiv mecarbil versus dobutamine and ivabradine co-treatment in pigs with acute ischemic heart failure. Physiol Rep 2018; 6:e13879. [PMID: 30311442 PMCID: PMC6182250 DOI: 10.14814/phy2.13879] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 08/30/2018] [Accepted: 09/03/2018] [Indexed: 02/01/2023] Open
Abstract
Acute ischemic cardiogenic shock is associated with poor prognosis, and the impact of inotropic support on diastolic function in this context is unclear. We assessed two suggested new inotropic strategies in a clinically relevant pig model of ischemic acute heart failure (AHF): treatment with the myosin activator omecamtiv mecarbil (OM) or dobutamine and ivabradine (D+I). Left ventricular (LV) ischemia was induced in anesthetized pigs by coronary microembolization (n = 12). The animals then received OM (bolus 0.75 mg/kg, followed by 0.5 mg/kg per h) (n = 6) or D+I (5 μg/kg per min + 0.29 ± 0.16 mg/kg) (n = 6), respectively. Ischemia reduced the stroke volume (SV), despite the increased left atrial pressure associated with impaired LV early relaxation, systolic dilatation, and LV late diastolic stiffness. Both treatments improved systolic ejection, but only D+I increased the SV from 26 ± 5 to 33 ± 5 mL. D+I enhanced LV early relaxation (Tau; from 45 ± 11 to 29 ± 4 msec) and prolonged the diastolic time (DT) from 338 ± 60 to 352 ± 40 msec. In contrast, OM prolonged Tau (42 ± 5 to 62 ± 10 msec) and shortened the DT (from 326 ± 68 to 248 ± 84 msec). Our data suggest that enhanced early relaxation by D+I improves LV pump function in postischemic acute heart failure. In contrast, OM worsened lusitropy in this model.
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Affiliation(s)
- Leif Rønning
- Cardiovascular Research GroupInstitute of Medical BiologyFaculty of Health SciencesUiT The Arctic University of NorwayTromsøNorway
| | - Jens P. Bakkehaug
- Cardiovascular Research GroupInstitute of Medical BiologyFaculty of Health SciencesUiT The Arctic University of NorwayTromsøNorway
| | - Lars Rødland
- Cardiovascular Research GroupInstitute of Medical BiologyFaculty of Health SciencesUiT The Arctic University of NorwayTromsøNorway
| | - Anders B. Kildal
- Cardiovascular Research GroupInstitute of Medical BiologyFaculty of Health SciencesUiT The Arctic University of NorwayTromsøNorway
| | - Truls Myrmel
- Cardiovascular Research GroupInstitute of Clinical MedicineFaculty of Health SciencesUiT The Arctic University of NorwayTromsøNorway
- Department of Cardiothoracic and Vascular Surgery, Heart and Lung ClinicUniversity Hospital of North NorwayTromsøNorway
| | - Ole‐Jakob How
- Cardiovascular Research GroupInstitute of Medical BiologyFaculty of Health SciencesUiT The Arctic University of NorwayTromsøNorway
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9
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Bakkehaug JP, Naesheim T, Torgersen Engstad E, Kildal AB, Myrmel T, How OJ. Reversing dobutamine-induced tachycardia using ivabradine increases stroke volume with neutral effect on cardiac energetics in left ventricular post-ischaemia dysfunction. Acta Physiol (Oxf) 2016; 218:78-88. [PMID: 27145482 DOI: 10.1111/apha.12704] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 04/03/2016] [Accepted: 05/02/2016] [Indexed: 12/01/2022]
Abstract
AIM Compensatory tachycardia can potentially be deleterious in acute heart failure. In this study, we tested a therapeutic strategy of combined inotropic support (dobutamine) and selective heart rate (HR) reduction through administration of ivabradine. METHODS In an open-chest pig model (n = 12) with left ventricular (LV) post-ischaemia dysfunction, cardiac function was assessed by LV pressure catheter and sonometric crystals. Coronary flow and blood samples from the coronary sinus were used to measure myocardial oxygen consumption (MVO2 ). LV energetics was assessed by comparing MVO2 with cardiac work at a wide range of workloads. RESULTS In the post-ischaemia heart, dobutamine (5 μg kg(-1) min(-1) ) increased cardiac output (CO) by increasing HR from 102 ± 21 to 131 ± 16 bpm (beats per min; P < 0.05). Adding ivabradine (0.5 mg kg(-1) ) slowed HR back to 100 ± 9 bpm and increased stroke volume from 30 ± 5 to 36 ± 5 mL (P < 0.05) by prolonging diastolic filling time and increasing end-diastolic dimensions. Adding ivabradine had no adverse effects on CO, mean arterial pressure and cardiac efficiency. Similar findings on efficiency and LV function were also seen using an ex vivo working mouse heart protocol. CONCLUSIONS A combined infusion of dobutamine and ivabradine had a neutral effect on post-ischaemia LV efficiency and increased left ventricular output without an increase in HR.
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Affiliation(s)
- J. P. Bakkehaug
- Cardiovascular Research Group; Institute of Medical Biology; Faculty of Health Sciences; UiT; The Arctic University of Norway; Tromsø Norway
| | - T. Naesheim
- Institute of Clinical Medicine; Faculty of Health Sciences; UiT; The Arctic University of Norway; Tromsø Norway
| | - E. Torgersen Engstad
- Cardiovascular Research Group; Institute of Medical Biology; Faculty of Health Sciences; UiT; The Arctic University of Norway; Tromsø Norway
| | - A. B. Kildal
- Cardiovascular Research Group; Institute of Medical Biology; Faculty of Health Sciences; UiT; The Arctic University of Norway; Tromsø Norway
| | - T. Myrmel
- Institute of Clinical Medicine; Faculty of Health Sciences; UiT; The Arctic University of Norway; Tromsø Norway
- Department of Cardiothoracic and Vascular Surgery; Heart and Lung Clinic; University Hospital of North Norway; Tromsø Norway
| | - O.-J. How
- Cardiovascular Research Group; Institute of Medical Biology; Faculty of Health Sciences; UiT; The Arctic University of Norway; Tromsø Norway
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10
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Ng GA. Neuro-cardiac interaction in malignant ventricular arrhythmia and sudden cardiac death. Auton Neurosci 2016; 199:66-79. [DOI: 10.1016/j.autneu.2016.07.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 07/02/2016] [Accepted: 07/04/2016] [Indexed: 12/30/2022]
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11
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Abstract
Elevated resting heart rate has been linked to poor outcomes in patients with chronic systolic heart failure. Blockade of funny current channel with ivabradine reduces heart rate without inotropic effects. Ivabradine was recently approved by US Food and Drug Administration for patients with stable, symptomatic chronic heart failure (HF) with left ventricular ejection fraction (LVEF) ≤35 %, who are in sinus rhythm with resting heart rate (HR) ≥ 70 bpm and either are on maximally tolerated doses of beta-blockers, or have a contraindication to beta-blockers. This article will review and evaluate the data supporting the use of ivabradine in patients with HF and explore its mechanisms and physiologic effects.
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Affiliation(s)
- Gabriela Orasanu
- Advanced Heart Failure and Transplantation Center, Harrington Heart & Vascular Institute, Department of Medicine, University Hospitals Case Medical Center, Case Western Reserve University School of Medicine, 11100 Euclid Avenue, Cleveland, OH, 44106, USA
| | - Sadeer G Al-Kindi
- Advanced Heart Failure and Transplantation Center, Harrington Heart & Vascular Institute, Department of Medicine, University Hospitals Case Medical Center, Case Western Reserve University School of Medicine, 11100 Euclid Avenue, Cleveland, OH, 44106, USA
| | - Guilherme H Oliveira
- Advanced Heart Failure and Transplantation Center, Harrington Heart & Vascular Institute, Department of Medicine, University Hospitals Case Medical Center, Case Western Reserve University School of Medicine, 11100 Euclid Avenue, Cleveland, OH, 44106, USA.
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12
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Scicchitano P, Cortese F, Ricci G, Carbonara S, Moncelli M, Iacoviello M, Cecere A, Gesualdo M, Zito A, Caldarola P, Scrutinio D, Lagioia R, Riccioni G, Ciccone MM. Ivabradine, coronary artery disease, and heart failure: beyond rhythm control. Drug Des Devel Ther 2014; 8:689-700. [PMID: 24940047 PMCID: PMC4051626 DOI: 10.2147/dddt.s60591] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Elevated heart rate could negatively influence cardiovascular risk in the general population. It can induce and promote the atherosclerotic process by means of several mechanisms involving endothelial shear stress and biochemical activities. Furthermore, elevated heart rate can directly increase heart ischemic conditions because of its skill in unbalancing demand/supply of oxygen and decreasing the diastolic period. Thus, many pharmacological treatments have been proposed in order to reduce heart rate and ameliorate the cardiovascular risk profile of individuals, especially those suffering from coronary artery diseases (CAD) and chronic heart failure (CHF). Ivabradine is the first pure heart rate reductive drug approved and currently used in humans, created in order to selectively reduce sinus node function and to overcome the many side effects of similar pharmacological tools (ie, β-blockers or calcium channel antagonists). The aim of our review is to evaluate the role and the safety of this molecule on CAD and CHF therapeutic strategies.
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Affiliation(s)
- Pietro Scicchitano
- Section of Cardiovascular Diseases, Department of Emergency and Organ Transplantation, University of Bari, School of Medicine, Policlinico, Bari, Italy
| | - Francesca Cortese
- Section of Cardiovascular Diseases, Department of Emergency and Organ Transplantation, University of Bari, School of Medicine, Policlinico, Bari, Italy
| | - Gabriella Ricci
- Section of Cardiovascular Diseases, Department of Emergency and Organ Transplantation, University of Bari, School of Medicine, Policlinico, Bari, Italy
| | - Santa Carbonara
- Section of Cardiovascular Diseases, Department of Emergency and Organ Transplantation, University of Bari, School of Medicine, Policlinico, Bari, Italy
| | - Michele Moncelli
- Section of Cardiovascular Diseases, Department of Emergency and Organ Transplantation, University of Bari, School of Medicine, Policlinico, Bari, Italy
| | - Massimo Iacoviello
- Section of Cardiovascular Diseases, Department of Emergency and Organ Transplantation, University of Bari, School of Medicine, Policlinico, Bari, Italy
| | - Annagrazia Cecere
- Section of Cardiovascular Diseases, Department of Emergency and Organ Transplantation, University of Bari, School of Medicine, Policlinico, Bari, Italy
| | - Michele Gesualdo
- Section of Cardiovascular Diseases, Department of Emergency and Organ Transplantation, University of Bari, School of Medicine, Policlinico, Bari, Italy
| | - Annapaola Zito
- Section of Cardiovascular Diseases, Department of Emergency and Organ Transplantation, University of Bari, School of Medicine, Policlinico, Bari, Italy
| | - Pasquale Caldarola
- Section of Cardiovascular Diseases, Policlinic, San Paolo Hospital, Bari, Italy
| | - Domenico Scrutinio
- Section of Cardiovascular Diseases, Fondazione Maugeri, Cassano Murge, Italy
| | - Rocco Lagioia
- Section of Cardiovascular Diseases, Fondazione Maugeri, Cassano Murge, Italy
| | - Graziano Riccioni
- Intensive Cardiology Care Unit, San Camillo de Lellis Hospital, Manfredonia, Foggia, Italy
| | - Marco Matteo Ciccone
- Section of Cardiovascular Diseases, Department of Emergency and Organ Transplantation, University of Bari, School of Medicine, Policlinico, Bari, Italy
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13
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Mechanisms underlying the autonomic modulation of ventricular fibrillation initiation--tentative prophylactic properties of vagus nerve stimulation on malignant arrhythmias in heart failure. Heart Fail Rev 2014; 18:389-408. [PMID: 22678767 PMCID: PMC3677978 DOI: 10.1007/s10741-012-9314-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Classical physiology teaches that vagal post-ganglionic nerves modulate the heart via acetylcholine acting at muscarinic receptors, whilst it is accepted that vagus nerve stimulation (VNS) slows heart rate, atrioventricular conduction and decreases atrial contraction; there is continued controversy as to whether the vagus has any significant direct effect on ventricular performance. Despite this, there is a significant body of evidence from experimental and clinical studies, demonstrating that the vagus nerve has an anti-arrhythmic action, protecting against induced and spontaneously occurring ventricular arrhythmias. Over 100 years ago Einbrodt first demonstrated that direct cervical VNS significantly increased the threshold for experimentally induced ventricular fibrillation. A large body of evidence has subsequently been collected supporting the existence of an anti-arrhythmic effect of the vagus on the ventricle. The development of prognostic indicators of heart rate variability and baroreceptor reflex sensitivity—measures of parasympathetic tone and reflex activation respectively—and the more recent interest in chronic VNS therapy are a direct consequence of the earlier experimental studies. Despite this, mechanisms underlying the anti-arrhythmic actions of the vagus nerve have not been fully characterised and are not well understood. This review summarises historical and recently published data to highlight the importance of this powerful endogenous protective phenomenon.
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14
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Mackiewicz U, Gerges JY, Chu S, Duda M, Dobrzynski H, Lewartowski B, Mączewski M. Ivabradine Protects Against Ventricular Arrhythmias in Acute Myocardial Infarction in the Rat. J Cell Physiol 2014; 229:813-23. [DOI: 10.1002/jcp.24507] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Accepted: 10/31/2013] [Indexed: 11/06/2022]
Affiliation(s)
- Urszula Mackiewicz
- Department of Clinical Physiology; Medical Center of Postgraduate Education; Warsaw Poland
| | - Joseph Y. Gerges
- School of Biomedical Sciences; University of Manchester; Manchester UK
| | - Sandy Chu
- School of Biomedical Sciences; University of Manchester; Manchester UK
| | - Monika Duda
- Department of Clinical Physiology; Medical Center of Postgraduate Education; Warsaw Poland
| | - Halina Dobrzynski
- School of Biomedical Sciences; University of Manchester; Manchester UK
| | - Bohdan Lewartowski
- Department of Clinical Physiology; Medical Center of Postgraduate Education; Warsaw Poland
| | - Michał Mączewski
- Department of Clinical Physiology; Medical Center of Postgraduate Education; Warsaw Poland
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15
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Vaillant F, Dehina L, Dizerens N, Bui-Xuan B, Tabib A, Lauzier B, Chevalier P, Descotes J, Timour Q. Ivabradine but not propranolol delays the time to onset of ischaemia-induced ventricular fibrillation by preserving myocardial metabolic energy status. Resuscitation 2013; 84:384-90. [DOI: 10.1016/j.resuscitation.2012.07.041] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 06/25/2012] [Accepted: 07/13/2012] [Indexed: 10/27/2022]
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16
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Ng FS, Shadi IT, Peters NS, Lyon AR. Selective heart rate reduction with ivabradine slows ischaemia-induced electrophysiological changes and reduces ischaemia-reperfusion-induced ventricular arrhythmias. J Mol Cell Cardiol 2013; 59:67-75. [PMID: 23402927 PMCID: PMC3654199 DOI: 10.1016/j.yjmcc.2013.02.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Revised: 02/01/2013] [Accepted: 02/03/2013] [Indexed: 01/28/2023]
Abstract
Heart rates during ischaemia and reperfusion are possible determinants of reperfusion arrhythmias. We used ivabradine, a selective If current inhibitor, to assess the effects of heart rate reduction (HRR) during ischaemia–reperfusion on reperfusion ventricular arrhythmias and assessed potential anti-arrhythmic mechanisms by optical mapping. Five groups of rat hearts were subjected to regional ischaemia by left anterior descending artery occlusion for 8 min followed by 10 min of reperfusion: (1) Control n = 10; (2) 1 μM of ivabradine perfusion n = 10; (3) 1 μM of ivabradine + 5 Hz atrial pacing throughout ischaemia–reperfusion n = 5; (4) 1 μM of ivabradine + 5 Hz pacing only at reperfusion; (5) 100 μM of ivabradine was used as a 1 ml bolus upon reperfusion. For optical mapping, 10 hearts (ivabradine n = 5; 5 Hz pacing n = 5) were subjected to global ischaemia whilst transmembrane voltage transients were recorded. Epicardial activation was mapped, and the rate of development of ischaemia-induced electrophysiological changes was assessed. HRR observed in the ivabradine group during both ischaemia (195 ± 11 bpm vs. control 272 ± 14 bpm, p < 0.05) and at reperfusion (168 ± 13 bpm vs. 276 ± 14 bpm, p < 0.05) was associated with reduced reperfusion ventricular fibrillation (VF) incidence (20% vs. 90%, p < 0.05). Pacing throughout ischaemia–reperfusion abolished the protective effects of ivabradine (100% VF), whereas pacing at reperfusion only partially attenuated this effect (40% VF). Ivabradine, given as a bolus at reperfusion, did not significantly affect VF incidence (80% VF). Optical mapping experiments showed a delay to ischaemia-induced conduction slowing (time to 50% conduction slowing: 10.2 ± 1.3 min vs. 5.1 ± 0.7 min, p < 0.05) and to loss of electrical excitability in ivabradine-perfused hearts (27.7 ± 4.3 min vs. 14.5 ± 0.6 min, p < 0.05). Ivabradine administered throughout ischaemia and reperfusion reduced reperfusion VF incidence through HRR. Heart rate during ischaemia is a major determinant of reperfusion arrhythmias. Heart rate at reperfusion alone was not a determinant of reperfusion VF, as neither a bolus of ivabradine nor pacing immediately prior to reperfusion significantly altered reperfusion VF incidence. This anti-arrhythmic effect of heart rate reduction during ischaemia may reflect slower development of ischaemia-induced electrophysiological changes.
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Affiliation(s)
- Fu Siong Ng
- National Heart & Lung Institute, Imperial College London, UK
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17
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Dehina L, Vaillant F, Tabib A, Bui-Xuan B, Chevalier P, Dizerens N, Bui-Xuan C, Descotes J, Blanc-Guillemaud V, Lerond L, Timour Q. Trimetazidine demonstrated cardioprotective effects through mitochondrial pathway in a model of acute coronary ischemia. Naunyn Schmiedebergs Arch Pharmacol 2012; 386:205-15. [PMID: 23263451 DOI: 10.1007/s00210-012-0826-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 12/10/2012] [Indexed: 02/06/2023]
Abstract
Myocardial ischemia affects mitochondrial function leading to ionic imbalance and susceptibility to ventricular fibrillation. Trimetazidine (TMZ), a metabolic agent, is clinically used as an anti-anginal therapy. This study was conducted to compare the effect of TMZ 20 mg immediate release (IR) and TMZ 35 mg modified release (MR), two bioequivalent marketed formulations of TMZ, on cardioprotection during acute ischemia in pigs. A 4-day oral treatment with TMZ 20 mg IR (800 mg, tid) or TMZ 35 mg MR (1,400 mg, bid) had no effect on ventricular fibrillation threshold (VFT) prior to ischemia but significantly prevented the decrease in VFT observed in placebo-treated groups after a 1-min left anterior descending coronary artery occlusion. This effect occurred without modifying cardiac hemodynamic and conduction parameters. In both TMZ-treated groups, a significant reduction of the ischemic area as well as a protection of cardiomyocytes were observed. Cardiac enzymatic activity (phosphorylase, succinate dehydrogenase, ATPase) was increased in TMZ-treated groups. Both formulations preserved mitochondrial structure and improved mitochondrial function as demonstrated by a twofold increase of oxidative phosphorylation, by a reduction of reactive oxygen species (ROS) production (>30 %) and by a trend to increase the mitochondrial calcium retention capacity. In this model of ischemia, both TMZ formulations, leading to equivalent TMZ plasma exposures, demonstrated similar cardioprotective effects. This protection could be attributed to a preservation of mitochondrial structure and function, which plays a central role in ATP and ROS production and consequently could be considered as a target of cardioprotection.
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Affiliation(s)
- L Dehina
- EA4612 Neurocardiologie, Université Claude Bernard - Lyon1, 8 avenue Rockefeller, 69373, Lyon cedex 08, France
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18
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Vaillant F, Dehina L, Mazzadi A, Descotes J, Chevalier P, Tabib A, Bui-Xuan B, Riera C, Belhani D, Timour Q. Heart rate reduction with ivabradine increases ischaemia-induced ventricular fibrillation threshold: Role of myocyte structure and myocardial perfusion. Resuscitation 2011; 82:1092-9. [DOI: 10.1016/j.resuscitation.2011.03.032] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 02/18/2011] [Accepted: 03/29/2011] [Indexed: 11/26/2022]
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19
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Abstract
A considerable body of evidence indicates that elevated resting heart rate is an independent, modifiable risk factor for cardiovascular events and mortality in patients with coronary artery disease. Elevated heart rate can produce adverse effects in several ways. Firstly, myocardial oxygen consumption is increased at high heart rates, but the time available for myocardial perfusion is reduced, increasing the likelihood of myocardial ischemia. Secondly, exposure of the large elastic arteries to cyclical stretch is increased at high heart rates. This effect can increase the rate at which components of the arterial wall deteriorate. Elastin fibers, which have an extremely slow rate of turnover in adult life, might be particularly vulnerable. Thirdly, elevated heart rate can predispose the myocardium to arrhythmias, and favor the development and progression of coronary atherosclerosis, by adversely affecting the balance between systolic and diastolic flow. Comparisons of the effects of the specific heart-rate-lowering drug ivabradine with those of β-blockers could help clarify the pathophysiological effects of elevated heart rate. Effective heart rate control among patients with coronary artery disease is uncommon in clinical practice, representing a missed therapeutic opportunity.
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Affiliation(s)
- Kim M Fox
- Royal Brompton Hospital, Sydney Street, London SW3 6NP, UK.
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20
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Cao YG, Jing S, Li L, Gao JQ, Shen ZY, Liu Y, Xing Y, Wu ML, Wang Y, Xu CQ, Sun HL. Antiarrhythmic effects and ionic mechanisms of oxymatrine from Sophora flavescens. Phytother Res 2011; 24:1844-9. [PMID: 20564505 DOI: 10.1002/ptr.3206] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Accumulating evidence indicates that oxymatrine may exert protective effects on the cardiovascular system. This study was designed to evaluate the antiarrhythmic effects as well as the electrophysiological properties of oxymatrine. The antiarrhythmic activity of oxymatrine was observed in a rat model of arrhythmia induced by coronary ligation. Action potential duration (APD), L-type calcium current (I(Ca-L) ), transient outward potassium current (I(to) ) and inward rectifier potassium current (I(K1)) in rat ventricular myocytes were recorded by utilizing the whole cell patch-clamp technique. The results showed that administration of oxymatrine significantly delayed the onset of ventricular arrhythmia, decreased the duration of ventricular arrhythmia and reduced the arrhythmia score of arrhythmic rats. The beneficial effects of oxymatrine may be related to the shortening of APD through reduction of I(Ca-L) , enhancement of I(to) and inhibition of I(K1).
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Affiliation(s)
- Yong-gang Cao
- Department of Pharmacology, Daqing Campus of Harbin Medical University, Daqing, 163319, P. R. China
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21
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Lauzier B, Vaillant F, Gélinas R, Bouchard B, Brownsey R, Thorin E, Tardif JC, Des Rosiers C. Ivabradine reduces heart rate while preserving metabolic fluxes and energy status of healthy normoxic working hearts. Am J Physiol Heart Circ Physiol 2011; 300:H845-52. [PMID: 21257916 DOI: 10.1152/ajpheart.01034.2010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Heart rate reduction (HRR) is an important target in the management of patients with chronic stable angina. Most available drugs for HRR, such as β-blockers, have adverse effects, including on cardiac energy substrate metabolism, a well-recognized determinant of cardiac homeostasis. This study aimed at 1) testing whether HRR by ivabradine (IVA) alters substrate metabolism in the healthy normoxic working heart and 2) comparing the effect of IVA with that of the β-blocker metoprolol (METO). This was assessed using our well-established model of ex vivo mouse heart perfusion in the working mode, which enables concomitant evaluation of myocardial contractility and metabolic fluxes using (13)C-labeled substrates. Hearts were perfused in the absence (controls; n = 10) or presence of IVA (n = 10, 3 μM) with or without atrial pacing to abolish HRR in the IVA group. IVA significantly reduced HR (35 ± 5%) and increased stroke volume (39 ± 9%) while maintaining similar cardiac output, contractility, power, and efficiency. Effects of IVA on HR and stroke volume were reversed by atrial pacing. At the metabolic level, IVA did not impact on substrate selection to citrate formation, rates of glycolysis, or tissue levels of high-energy phosphates. In contrast, METO, at concentrations up to 40 μM, decreased markedly cardiac function (flow: 25 ± 6%; stroke volume: 30 ± 10%; contractility: 31 ± 9%) as well as glycolysis (2.9-fold) but marginally affected HR. Collectively, these results demonstrate that IVA selectively reduces HR while preserving energy substrate metabolism of normoxic healthy working mouse hearts perfused ex vivo, a model that mimics to some extent the denervated transplanted heart. Our results provide the impetus for testing selective HRR by IVA on cardiac substrate metabolism in pathological models.
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Affiliation(s)
- Benjamin Lauzier
- Departments of Nutrition, Montreal Heart Institute and Université de Montréal, Montreal, Quebec, Canada
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22
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Thollon C, Vilaine JP. I(f) inhibition in cardiovascular diseases. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2010; 59:53-92. [PMID: 20933199 DOI: 10.1016/s1054-3589(10)59003-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Heart rate (HR) is determined by the pacemaker activity of cells from the sinoatrial node (SAN), located in the right atria. Spontaneous electrical activity of SAN cells results from a diastolic depolarization (DD). Despite controversy in the exact contribution of funny current (I(f)) in pacemaking, it is a major contributor of DD. I(f) is an inward Na(+)/K(+) current, activated upon hyperpolarization and directly modulated by cyclic adenosine monophosphate. The f-proteins are hyperpolarization-activated cyclic nucleotide-gated channels, HCN4 being the main isoform of SAN. Ivabradine (IVA) decreases DD and inhibits I(f) in a use-dependent manner. Under normal conditions IVA selectively reduces HR and limits exercise-induced tachycardia, in animals and young volunteers. Reduction in HR with IVA both decreases myocardial oxygen consumption and increases its supply due to prolongation of diastolic perfusion time. In animal models and in human with coronary artery disease (CAD), IVA has anti-anginal and anti-ischemic efficacy, equipotent to classical treatments, β-blockers, or calcium channel blockers. As expected from its selectivity for I(f), the drug is safe and well tolerated with minor visual side effects. As a consequence, IVA is the first inhibitor of I(f) approved for the treatment of stable angina. Available clinical data indicate that IVA could improve the management of stable angina in all patients including those treated with β-blockers. As chronic elevation of resting HR is an independent predictor of mortality, pure HR reduction by inhibition of I(f) could, beyond the control of anti-anginal symptoms, improve the prognosis of CAD and heart failure; this therapeutic potential is currently under evaluation with IVA.
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Affiliation(s)
- Catherine Thollon
- Cardiovascular Department, Institut de Recherches Servier, Suresnes, France
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23
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Fasullo S, Cannizzaro S, Maringhini G, Ganci F, Giambanco F, Vitale G, Pinto V, Migliore G, Torres D, Sarullo FM, Paterna S, Di Pasquale P. Comparison of Ivabradine Versus Metoprolol in Early Phases of Reperfused Anterior Myocardial Infarction With Impaired Left Ventricular Function: Preliminary Findings. J Card Fail 2009; 15:856-63. [DOI: 10.1016/j.cardfail.2009.05.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2009] [Revised: 05/15/2009] [Accepted: 05/21/2009] [Indexed: 11/27/2022]
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24
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Berdeaux A, Tissier R, Couvreur N, Salouage I, Ghaleh B. [Heart rate reduction: beneficial effects in heart failure and post-infarcted myocardium]. Therapie 2009; 64:87-91. [PMID: 19664401 DOI: 10.2515/therapie/2009013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Heart rate (HR) is an independent predicting factor of cardiovascular events in patients with advanced heart failure. Clinical trials conducted with beta-blockers have demonstrated that reduction of HR is a fundamental mechanism to explain the reduction of morbidity-mortality in such a disease. Trials conducted with ivabradine, the first selective inhibitor of the I(f) current in cardiac pacemaker cells, have also clearly confirmed that reduction of HR lead to powerful and sustained favourable effects in patients with cardiac failure and post-infarcted myocardial diseases. These effects are not only due to the reduction of the risk factors associated with myocardial ischemia but also to the reduction of cardiac and perivascular fibrosis associated with the remodelling process at the ventricular level. Although the mechanisms associated with reduction of HR following administration of beta-blockers and ivabradine are to a large extent similar, others like their effects on post-systolic contraction are totally opposed. So, new clinical trials are necessary to know whether it is possible to substitute these drugs or conversely to associate them for an optimal therapeutic strategy in patients with advanced heart failure and post-infarcted myocardium.
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Affiliation(s)
- Alain Berdeaux
- Laboratoire de Pharmacologie, Faculté de Médecine de Créteil et Fédération de Cardiologie de l'Hôpital Henri Mondor, Créteil, France.
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