1
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Malkoc A, Phan A, Falatoonzadeh P, Mac O, Sherman W, Wong DT. Gender Differences With Ibutilide Effectiveness and Safety in Cardioversion of Atrial Fibrillation. J Surg Res 2024; 296:10-17. [PMID: 38181644 DOI: 10.1016/j.jss.2023.12.002] [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: 05/25/2023] [Revised: 11/13/2023] [Accepted: 12/07/2023] [Indexed: 01/07/2024]
Abstract
INTRODUCTION Few studies have examined the use of ibutilide in noncardiac surgical populations. Our study considered the effectiveness and safety of ibutilide in cardioversion of atrial fibrillation (AF) in medical and surgical intensive care patients. METHODS A retrospective chart review was performed for patients with a confirmed diagnosis of AF who were hemodynamically stable and received ibutilide after the initial diagnosis. Patients were administered 1 mg of ibutilide fumarate intravenous for 10 min with a second dose administered if AF persisted after 30 min. Patients were pretreated with intravenous magnesium sulfate if their blood magnesium level was <2 mg/dL. RESULTS Fifty seven total female patients and 99 male patients received ibutilide. Females had an 88% conversion rate to normal sinus rhythm (NSR) compared to 68% in males (P = 0.008). A 70% successful return to NSR was observed in patients from all groups pretreated with magnesium sulfate (P = 0.045). One year after discharge, 74% of the patients stayed in the NSR. CONCLUSIONS Within our population, pretreatment with magnesium sulfate followed by ibutilide was associated with increased conversion to NSR. Additionally, we noted that females had a higher conversion rate to NSR compared to males, regardless of whether they were pretreated with magnesium sulfate.
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Affiliation(s)
- Aldin Malkoc
- Department of Surgery, Arrowhead Regional Medical Center, Colton, California
| | - Alexander Phan
- Department of Surgery, Arrowhead Regional Medical Center, Colton, California
| | - Payam Falatoonzadeh
- Department of Surgery, Arrowhead Regional Medical Center, Colton, California
| | - Olivia Mac
- Department of Surgery, Arrowhead Regional Medical Center, Colton, California
| | - William Sherman
- Department of Surgery, Arrowhead Regional Medical Center, Colton, California
| | - David T Wong
- Department of Surgery, Arrowhead Regional Medical Center, Colton, California.
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2
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Iachetta G, Melle G, Colistra N, Tantussi F, De Angelis F, Dipalo M. Long-term in vitro recording of cardiac action potentials on microelectrode arrays for chronic cardiotoxicity assessment. Arch Toxicol 2023; 97:509-522. [PMID: 36607357 PMCID: PMC9859891 DOI: 10.1007/s00204-022-03422-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 11/15/2022] [Indexed: 01/07/2023]
Abstract
The reliable identification of chronic cardiotoxic effects in in vitro screenings is fundamental for filtering out toxic molecular entities before in vivo animal experimentation and clinical trials. Present techniques such as patch-clamp, voltage indicators, and standard microelectrode arrays do not offer at the same time high sensitivity for measuring transmembrane ion currents and low-invasiveness for monitoring cells over long time. Here, we show that optoporation applied to microelectrode arrays enables measuring action potentials from human-derived cardiac syncytia for more than 1 continuous month and provides reliable data on chronic cardiotoxic effects caused by known compounds such as pentamidine. The technique has high potential for detecting chronic cardiotoxicity in the early phases of drug development.
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Affiliation(s)
| | | | | | | | | | - Michele Dipalo
- Istituto Italiano di Tecnologia, Via Morego 30, 16163, Genova, Italy.
- FORESEE Biosystems Srl, Genova, Italy.
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3
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Bílek R, Danzig V, Grimmichová T. Antiviral activity of amiodarone in SARS-CoV-2 disease. Physiol Res 2022. [DOI: 10.33549/physiolres.934974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Amiodarone seems to exhibit some antiviral activity in the disease caused by SARS-CoV-2. Here we have examined the SARS-CoV-2 disease course in the entire population of the Czech Republic and compared it with the course of the disease in patients treated with amiodarone in two major Prague’s hospitals. In the whole population of the Czech Republic SARS-CoV-2 infected 1665070 persons (15.6 %) out of 10694000 (100 %) between 1 April 2020 and 30 June 2021. In the same time period only 35 patients (3.4 %) treated with amiodarone were infected with SARS-CoV-2 virus out of 1032 patients (100 %) who received amiodarone. It appears that amiodarone can prevent SARS-CoV-2 virus infection by multiple mechanisms. In in-vitro experiments it exhibits SARS-CoV-2 virus replication inhibitions. Due to its anti-inflammatory and antioxidant properties, it may have beneficial effect on the complications caused by SARS-CoV-2 as well. Additionally, inorganic iodine released from amiodarone can be converted to hypoiodite (IO-), which has antiviral and antibacterial activity, and thus can affect the life cycle of the virus.
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Affiliation(s)
- R Bílek
- Institute of Endocrinology, Národní 8, 110 00 Prague 1, Czech Republic. ,
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4
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Zaki HA, Bashir K, Iftikhar H, Salem W, Mohamed EH, Elhag HM, Hendy M, Kassem AAO, Salem EED, Elmoheen A. An Integrative Comparative Study Between Digoxin and Amiodarone as an Emergency Treatment for Patients With Atrial Fibrillation With Evidence of Heart Failure: A Systematic Review and Meta-Analysis. Cureus 2022; 14:e26800. [PMID: 35971374 PMCID: PMC9372377 DOI: 10.7759/cureus.26800] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/13/2022] [Indexed: 11/06/2022] Open
Abstract
The emergency treatment of atrial fibrillation (AF) involves utilizing two strategies. The first strategy normally involves permitting the atrial fibrillation to persevere as the ventricular rate is controlled. The other method involves utilizing anti-arrhythmic drugs in cardioversion and attempting to maintain sinus rhythm. Different pharmacological treatments, including digoxin and amiodarone, have been used to manage AF. A literature review on amiodarone and digoxin in the treatment of AF among patients with heart failure (HF) has shown that both drugs have potential risks. Therefore, we are conducting this systematic review and meta-analysis to compare the effectiveness of amiodarone and digoxin in the treatment of AF among patients with evidence of HF. A literature search of relevant articles was conducted on six electronic databases (PubMed, Web of Science, Medline, ScienceDirect, Cochrane Library, and Google Scholar) from 2000 to 2022. The search yielded seven studies that had met the inclusion criteria. Our meta-analysis of four studies showed that there was no significant difference in the reduction of heart rate after treatment with either amiodarone or digoxin (mean difference (MD): -5.44; 95% confidence interval (CI): -9.53 to -1.34; I2 = 25%; p = 0.26). On the other hand, the statistical analysis showed that amiodarone had a better effect on the conversion to sinus rhythm than digoxin (63% versus 35%, respectively). Based on evidence from our meta-analysis, the clinical effect of amiodarone and digoxin in the emergency treatment of AF on heart rate control was unclear. However, amiodarone has a significant impact on the restoration of sinus rhythm compared with digoxin and can be considered the first-line drug regimen in conversion to sinus rhythm for AF patients with evidence of heart failure. However, the use of amiodarone and digoxin is complicated by adverse events and all-cause mortality.
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5
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The Antiarrhythmic Activity of Novel Pyrrolidin-2-one Derivative S-75 in Adrenaline-Induced Arrhythmia. Pharmaceuticals (Basel) 2021; 14:ph14111065. [PMID: 34832847 PMCID: PMC8625052 DOI: 10.3390/ph14111065] [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: 08/26/2021] [Revised: 10/13/2021] [Accepted: 10/14/2021] [Indexed: 11/29/2022] Open
Abstract
Arrhythmia is a quivering or irregular heartbeat that can often lead to blood clots, stroke, heart failure, and other heart-related complications. The limited efficacy and safety of antiarrhythmic drugs require the design of new compounds. Previous research indicated that pyrrolidin-2-one derivatives possess an affinity for α1-adrenergic receptors. The blockade of α1-adrenoceptor may play a role in restoring normal sinus rhythm; therefore, we aimed to verify the antiarrhythmic activity of novel pyrrolidin-2-one derivative S-75. In this study, we assessed the influence on sodium, calcium, potassium channels, and β1-adrenergic receptors to investigate the mechanism of action of S-75. Lack of affinity for β1-adrenoceptors and weak effects on ion channels decreased the role of these adrenoceptors and channels in the pharmacological activity of S-75. Next, we evaluated the influence of S-75 on normal ECG in rats and isolated rat hearts, and the tested derivative did not prolong the QTc interval, which may confirm the lack of the proarrhythmic potential. We tested antiarrhythmic activity in adrenaline-, aconitine- and calcium chloride-induced arrhythmia models in rats. The studied compound showed prophylactic antiarrhythmic activity in the adrenaline-induced arrhythmia, but no significant activity in the model of aconitine- or calcium chloride-induced arrhythmia. In addition, S-75 was not active in the model of post-reperfusion arrhythmias of the isolated rat hearts. Conversely, the compound showed therapeutic antiarrhythmic properties in adrenaline-induced arrhythmia, reducing post-arrhythmogen heart rhythm disorders, and decreasing animal mortality. Thus, we suggest that the blockade of α1-adrenoceptor might be beneficial in restoring normal heart rhythm in adrenaline-induced arrhythmia.
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6
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Lévy S. Cardioversion of recent-onset atrial fibrillation using intravenous antiarrhythmics: A European perspective. J Cardiovasc Electrophysiol 2021; 32:3259-3269. [PMID: 34662471 DOI: 10.1111/jce.15264] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 09/13/2021] [Accepted: 10/05/2021] [Indexed: 11/28/2022]
Abstract
Pharmacological cardioversion using intravenous antiarrhythmic agents is commonly indicated in symptomatic patients with recent-onset atrial fibrillation (AF). Except in hemodynamically unstable patients who require emergency direct current electrical cardioversion, for the majority of hemodynamically stable patients, pharmacological cardioversion represents a valid option and requires the clinician to be familiar with the properties and use of antiarrhythmic agents. The main characteristics of selected intravenous antiarrhythmic agents for conversion of recent-onset AF, the reported success rates, and possible adverse events are discussed. Among intravenous antiarrhythmics, flecainide, propafenone, amiodarone, sotalol, dofetilide, ibutilide, and vernakalant are commonly used. Antazoline, an old antihistaminic agent with antiarrhythmic properties was also reported to give encouraging results in Poland. Intravenous flecainide and propafenone are the only Class I agents still recommended by recent guidelines. Intravenous new Class III agents as dofetilide and ibutilide have high and rapid efficacy in converting AF to sinus rhythm but require strict surveillance with electrocardiogram (ECG) monitoring during and after intravenous administration because of the potential risk of QT prolongation and Torsades de Pointes, which can be prevented and properly managed. Vernakalant, a partial atrial selective was shown to have a high success rate and to be safe in real-life use.
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Affiliation(s)
- Samuel Lévy
- Marseille School of Medicine, Aix-Marseille University, Marseille, France
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7
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Yang PC, Giles WR, Belardinelli L, Clancy CE. Mechanisms of flecainide induced negative inotropy: An in silico study. J Mol Cell Cardiol 2021; 158:26-37. [PMID: 34004185 PMCID: PMC8772296 DOI: 10.1016/j.yjmcc.2021.05.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 11/27/2022]
Abstract
It is imperative to develop better approaches to predict how antiarrhythmic drugs with multiple interactions and targets may alter the overall electrical and/or mechanical function of the heart. Safety Pharmacology studies have provided new insights into the multi-target effects of many different classes of drugs and have been aided by the addition of robust new in vitro and in silico technology. The primary focus of Safety Pharmacology studies has been to determine the risk profile of drugs and drug candidates by assessing their effects on repolarization of the cardiac action potential. However, for decades experimental and clinical studies have described substantial and potentially detrimental effects of Na+ channel blockers in addition to their well-known conduction slowing effects. One such side effect, associated with administration of some Na+ channel blocking drugs is negative inotropy. This reduces the pumping function of the heart, thereby resulting in hypotension. Flecainide is a well-known example of a Na+ channel blocking drug, that exhibits strong rate-dependent block of INa and may cause negative cardiac inotropy. While the phenomenon of Na+ channel suppression and resulting negative inotropy is well described, the mechanism(s) underlying this effect are not. Here, we set out to use a modeling and simulation approach to reveal plausible mechanisms that could explain the negative inotropic effect of flecainide. We utilized the Grandi-Bers model [1] of the cardiac ventricular myocyte because of its robust descriptions of ion homeostasis in order to characterize and resolve the relative effects of QRS widening, flecainide off-target effects and changes in intracellular Ca2+ and Na+ homeostasis. The results of our investigations and predictions reconcile multiple data sets and illustrate how multiple mechanisms may play a contributing role in the flecainide induced negative cardiac inotropic effect.
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Affiliation(s)
- Pei-Chi Yang
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, United States of America
| | - Wayne R Giles
- Department of Physiology & Pharmacology, University of Calgary, Canada
| | | | - Colleen E Clancy
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, United States of America.
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8
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Rigopoulos AG, Kalogeropoulos AS, Tsoporis JN, Sakadakis EA, Triantafyllis AS, Noutsias M, Gupta S, Parker TG, Rizos I. Heat Shock Protein 70 Is Associated With Cardioversion Outcome and Recurrence of Symptomatic Recent Onset Atrial Fibrillation in Hypertensive Patients. J Cardiovasc Pharmacol 2021; 77:360-369. [PMID: 33298735 DOI: 10.1097/fjc.0000000000000962] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Accepted: 11/11/2020] [Indexed: 11/26/2022]
Abstract
ABSTRACT Accumulating evidence indicates that heat shock proteins (HSPs) may represent a suitable biomarker to predict atrial fibrillation (AF). We investigated the relation of circulating serum HSP70 (sHSP70) with inflammatory cytokines and recurrence of symptomatic recent onset AF (ROAF). We enrolled 90 patients with ROAF (the duration from onset of symptoms ≤24 hours) and 30 controls. Patients received amiodarone for cardioversion and rhythm control. The association of serum HSP70, serum interleukin-2 (sIL-2), and serum interleukin-4 (sIL-4) with the presence of cardioversion and AF recurrence within a year was investigated. Toll-like receptor 4 (TLR4) signaling dependence for IL-2 and IL-4 induction in response to stimulation with HSP70 was tested in rat aortic vascular smooth muscle cell cultures. Patients had higher sHSP70 and sIL-2 and lower sIL-4 compared with controls. Serum HSP70 was independently associated with ROAF (P = 0.005) and correlated with sIL-2 (r = 0.494, P < 0.001) and sIL-4 (r = -0.550, P < 0.001). By 48 hours, 71 of the 90 patients were cardioverted, with noncardioverted patients having higher sHSP70 and sIL-2 and lower sIL-4, which were the only independent factors associated with cardioversion. AF recurred in 38 of the 71 cardioverted patients in 1 year. A cutoff value of sHSP70 ≥0.65 ng/mL and sIL-2 ≥0.21 pg/mL was the only independent factor associated with AF recurrence (hazard ratio: 3.311, 95% confidence interval: 1.503-7.293, P = 0.003 and hazard ratio: 3.144, 95% confidence interval: 1.341-7.374, P = 0.008, respectively). The exposure of smooth muscle cell to HSP70 in vitro increased the expression of IL-2 (5×) and IL-4 (1.5×) through TLR4-dependent and receptor-independent mechanisms. In conclusion, sHSP70 and sIL-2 might constitute a prognostic tool for determining the cardioversion and recurrence likelihood in ROAF.
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Affiliation(s)
- Angelos G Rigopoulos
- 2nd Department of Cardiology, University of Athens Medical School, Attikon University Hospital, Athens, Greece
- Department of Internal Medicine III, Mid-German Heart Center, Division of Cardiology, Angiology and Intensive Medical Care, University Hospital Halle, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany ; and
| | - Andreas S Kalogeropoulos
- 2nd Department of Cardiology, University of Athens Medical School, Attikon University Hospital, Athens, Greece
| | - James N Tsoporis
- The Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Eleftherios A Sakadakis
- 2nd Department of Cardiology, University of Athens Medical School, Attikon University Hospital, Athens, Greece
| | - Andreas S Triantafyllis
- 2nd Department of Cardiology, University of Athens Medical School, Attikon University Hospital, Athens, Greece
| | - Michel Noutsias
- Department of Internal Medicine III, Mid-German Heart Center, Division of Cardiology, Angiology and Intensive Medical Care, University Hospital Halle, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany ; and
| | - Sahil Gupta
- The Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Thomas G Parker
- The Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Ioannis Rizos
- 2nd Department of Cardiology, University of Athens Medical School, Attikon University Hospital, Athens, Greece
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9
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Kelly MA. Neurological complications of cardiovascular drugs. HANDBOOK OF CLINICAL NEUROLOGY 2021; 177:319-344. [PMID: 33632450 DOI: 10.1016/b978-0-12-819814-8.00020-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Cardiovascular drugs are used to treat arterial hypertension, hyperlipidemia, arrhythmias, heart failure, and coronary artery disease. They also include antiplatelet and anticoagulant drugs that are essential for prevention of cardiogenic embolism. Most neurologic complications of the cardiovascular drugs are minor or transient and are far outweighed by the anticipated benefits of treatment. Other neurologic complications are more serious and require early recognition and management. Overtreatment of arterial hypertension may cause lightheadedness or fatigue but often responds readily to dose adjustment or an alternative drug. Other drug complications may be more troublesome as in myalgia associated with statins or headache associated with vasodilators. The recognized bleeding risk of the antithrombotics requires careful calculation of risk/benefit ratios for individual patients. Many neurologic complications of cardiovascular drugs are well documented in clinical trials with known frequency and severity, but others are rare and recognized only in isolated case reports or small case series. This chapter draws on both sources to report the adverse effects on muscle, nerve, and brain associated with commonly used cardiovascular drugs.
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Affiliation(s)
- Michael A Kelly
- Department of Neurology, Loyola University Chicago, Stritch School of Medicine, Maywood, IL, United States.
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10
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Atrial Fibrillation in COVID-19: From Epidemiological Association to Pharmacological Implications. J Cardiovasc Pharmacol 2020; 76:138-145. [PMID: 32453074 DOI: 10.1097/fjc.0000000000000854] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Coronavirus disease 2019 (COVID-19) outbreak is a public health emergency of international concerns because of a highly pathogenic human coronavirus (HCoV), actually named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Despite much emerging data about the epidemiological association between cardiovascular diseases and COVID-19, little is still known about atrial fibrillation and its optimal management in this clinical contest. The aim of our review is to describe the pharmacological interactions between cardiovascular drugs more commonly used in atrial fibrillation management and experimental COVID-19 therapies, based on EU and US summaries of product characteristics.
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11
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Abstract
Atrial fibrillation (AF) is the most common arrhythmia and its management may be organized into risk stratification and/or treatment of heart failure, stroke prevention, and symptom control. At the core of symptom control, treatment is tailored to either allow AF continue with controlled heart rates, so-called rate control, versus restoring and maintaining sinus rhythm or rhythm control. Rate control strategies mainly use rate-modulating medications, whereas rhythm control treatment includes therapy aimed at restoring sinus rhythm, including pharmacologic and direct current cardioversion, as well as maintenance of sinus rhythm, including antiarrhythmic medications and ablation therapy.
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Affiliation(s)
- Vishal Dahya
- Cardiovascular Disease, Summa Health System, NEOMED University, Akron City Hospital, 95 Arch Street, Suite 300, Akron, OH 44304, USA
| | - Tyler L Taigen
- Section of Pacing and Electrophysiology, Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue/J2, Cleveland, OH 44195, USA.
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12
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Patejdl R, Gromann A, Bänsch D, Noack T. Effects of ajmaline on contraction patterns of isolated rat gastric antrum and portal vein smooth muscle strips and on neurogenic relaxations of gastric fundus. Pflugers Arch 2019; 471:995-1005. [PMID: 31044280 DOI: 10.1007/s00424-019-02279-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 04/03/2019] [Accepted: 04/24/2019] [Indexed: 12/23/2022]
Abstract
Class-I-antiarrhythmics like ajmaline are known to alter smooth muscle function, which may cause alterations in gastrointestinal motility. The effects of ajmaline on isolated gastric and portal vein smooth muscle and the underlying mechanisms are unknown. We studied the effects of ajmaline on the contractile patterns of isolated preparations of gastric antrum and portal vein from Wistar rats. The organ bath technique was used to measure spontaneous or pharmacologically induced isometric contractions. Changes in force observed after application of ajmaline or under control conditions are reported as % of the amplitude of an initial K+-induced contraction. Electric field stimulation was used to study neurogenic relaxations of gastric fundus smooth muscle. Ajmaline increased the amplitude of spontaneous contractions of muscle strips (portal vein: control 31.1 ± 15.2%, with 100 μM ajmaline 76.6 ± 32.3%, n = 9, p < 0.01; gastric antrum: control 9.5 ± 1.6%, with 100 μM ajmaline 63.9 ± 9.96%, n = 14, p < 0.01). The frequency of spontaneous activity was reduced in portal vein, but not in gastric antrum strips. The effects of ajmaline were not blocked by tetrodotoxin, L-nitroarginine methyl ester, or atropine. Ajmaline abolished coordinated neurogenic relaxations triggered by electric field stimulation and partly reversed the inhibition of GA spontaneous activity caused by the gap junction blocker carbenoxolone. Ajmaline enhances the amplitude of spontaneous contractions in rat gastric and portal vein smooth muscle. This effect may be accompanied, but not caused by an inhibition of enteric neurotransmission. Enhanced syncytial coupling as indicated by its ability to antagonize the effects of carbenoxolone is likely to underlie the enhancement of contractility.
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Affiliation(s)
- Robert Patejdl
- Oscar-Langendorff-Institut für Physiologie, Universitätsmedizin Rostock, Gertrudenstraße 9, 18057, Rostock, Germany.
| | - Alina Gromann
- Oscar-Langendorff-Institut für Physiologie, Universitätsmedizin Rostock, Gertrudenstraße 9, 18057, Rostock, Germany
| | - Dietmar Bänsch
- Department of Cardiac Electrophysiology, KMG Hospital Güstrow, Güstrow, Germany
| | - Thomas Noack
- Oscar-Langendorff-Institut für Physiologie, Universitätsmedizin Rostock, Gertrudenstraße 9, 18057, Rostock, Germany
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13
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Hohendanner F, Heinzel FR, Blaschke F, Pieske BM, Haverkamp W, Boldt HL, Parwani AS. Pathophysiological and therapeutic implications in patients with atrial fibrillation and heart failure. Heart Fail Rev 2019; 23:27-36. [PMID: 29038991 DOI: 10.1007/s10741-017-9657-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Heart failure and atrial fibrillation are common and responsible for significant mortality of patients. Both share the same risk factors like hypertension, ischemic heart disease, diabetes, obesity, arteriosclerosis, and age. A variety of microscopic and macroscopic changes favor the genesis of atrial fibrillation in patients with preexisting heart failure, altered subcellular Ca2+ homeostasis leading to increased cellular automaticity as well as concomitant fibrosis that are induced by pressure/volume overload and altered neurohumoral states. Atrial fibrillation itself promotes clinical deterioration of patients with preexisting heart failure as atrial contraction significantly contributes to ventricular filling. In addition, atrial fibrillation induced tachycardia can even further compromise ventricular function by inducing tachycardiomyopathy. Even though evidence has been provided that atrial functions significantly and independently of confounding ventricular pathologies, correlate with mortality of heart failure patients, rate and rhythm controls have been shown to be of equal effectiveness in improving mortality. Yet, it also has been shown that cohorts of patients with heart failure benefit from a rhythm control concept regarding symptom control and hospitalization. To date, amiodarone is the most feasible approach to restore sinus rhythm, yet its use is limited by its extensive side-effect profile. In addition, other therapies like catheter-based pulmonary vein isolation are of increasing importance. A wide range of heart failure-specific therapies are available with mixed impact on new onset or perpetuation of atrial fibrillation. This review highlights pathophysiological concepts and possible therapeutic approaches to treat patients with heart failure at risk for or with atrial fibrillation.
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Affiliation(s)
- Felix Hohendanner
- Department of Cardiology, Charité University Medicine, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany. .,Partner Site Berlin, German Center for Cardiovascular Research (DZHK), Berlin, Germany.
| | - F R Heinzel
- Department of Cardiology, Charité University Medicine, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany.,Partner Site Berlin, German Center for Cardiovascular Research (DZHK), Berlin, Germany
| | - F Blaschke
- Department of Cardiology, Charité University Medicine, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany.,Partner Site Berlin, German Center for Cardiovascular Research (DZHK), Berlin, Germany
| | - B M Pieske
- Department of Cardiology, Charité University Medicine, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany.,Partner Site Berlin, German Center for Cardiovascular Research (DZHK), Berlin, Germany.,Department of Internal Medicine and Cardiology, German Heart Center, 13353, Berlin, Germany
| | - W Haverkamp
- Department of Cardiology, Charité University Medicine, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany.,Partner Site Berlin, German Center for Cardiovascular Research (DZHK), Berlin, Germany
| | - H L Boldt
- Department of Cardiology, Charité University Medicine, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany.,Partner Site Berlin, German Center for Cardiovascular Research (DZHK), Berlin, Germany
| | - A S Parwani
- Department of Cardiology, Charité University Medicine, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany.,Partner Site Berlin, German Center for Cardiovascular Research (DZHK), Berlin, Germany
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14
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Watanabe T, Inoue K, Kashiwase K, Mine T, Hirooka K, Shutta R, Mizuno H, Okuyama Y, Sakata Y, Nanto S. Differences in amiodarone efficacy in relation to ejection fraction and basal rhythm in patients with implantable cardioverter defibrillators. J Electrocardiol 2018; 51:1111-1115. [PMID: 30497740 DOI: 10.1016/j.jelectrocard.2018.10.083] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 09/23/2018] [Accepted: 10/06/2018] [Indexed: 11/19/2022]
Abstract
BACKGROUND Atrial fibrillation (AF) and ventricular arrhythmias (VAs) are associated with increased morbidity and mortality. However, data are lacking concerning the association of AF and VAs. This study aimed to clarify the association between AF and VAs and to investigate the effect of amiodarone on the incidence of VAs in patients with implantable cardioverter defibrillators (ICDs). METHODS AND RESULTS We enrolled 612 patients who had ICDs or who underwent cardiac resynchronization therapy with a defibrillator (CRT-D) and classified them into two groups (sinus rhythm [SR] group, n = 427; AF group, n = 185) according to their basal rhythm at enrollment. Patients with paroxysmal AF were grouped into the AF group. The incidence of VAs, i.e., ventricular tachycardia (VT) and ventricular fibrillation (VF), was significantly lower in the AF group than in the SR group (0.54 vs 0.95 episodes/person/year, P = 0.032). Furthermore, amiodarone use was significantly higher in the AF group than in the SR group (P = 0.003). Non-use of amiodarone was associated with a significant increase in the occurrence of VT/VF in the two groups. This beneficial suppressive effect of amiodarone on the incidence of VT/VF was present in the AF group regardless of left ventricular ejection fraction (LVEF). However, this effect of amiodarone was present only in patients with LVEF ≥ 40% in the SR group. CONCLUSIONS Amiodarone was negatively associated with VT/VF occurrence and was frequently used in ICD/CRT-D patients with AF. VT/VF was controlled by amiodarone in all cases in the AF group but only in patients with an LVEF ≥ 40% in the SR group.
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Affiliation(s)
- Tetsuya Watanabe
- Department of Cardiovascular Medicine, Yao Municipal Hospital, Yao, Japan.
| | - Koichi Inoue
- Cardiovascular Center, Sakurabashi Watanabe Hospital, Osaka, Japan
| | - Kazunori Kashiwase
- Department of Internal Medicine, Cardiovascular Division, Hyogo College of Medicine, Hyogo, Japan
| | - Takanao Mine
- Department of Internal Medicine, Cardiovascular Division, Hyogo College of Medicine, Hyogo, Japan
| | - Keiji Hirooka
- Cardiovascular Division, Osaka Saiseikai Senri Hospital, Osaka, Japan
| | - Ryu Shutta
- Division of Cardiology, Osaka Rosai Hospital, Osaka, Japan
| | - Hiroya Mizuno
- Department of Cardiovascular Medicine, Osaka University School of Medicine, Suita, Japan
| | - Yuji Okuyama
- Cardiovascular Division, National Hospital Organization Osaka Minami Medical Center, Osaka, Japan
| | - Yasushi Sakata
- Department of Cardiovascular Medicine, Osaka University School of Medicine, Suita, Japan
| | - Shinsuke Nanto
- Department of Cardiology, Nishinomiya Municipal Central Hospital, Nishinomiya, Japan
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15
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STEINBERG JONATHANS, SHAH YASH, SZEPIETOWSKA BARBARA. Pharmacologic Conversion during Dofetilide Treatment for Persistent Atrial Fibrillation. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2017; 40:667-671. [DOI: 10.1111/pace.13055] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 02/01/2017] [Accepted: 02/11/2017] [Indexed: 11/29/2022]
Affiliation(s)
- JONATHAN S. STEINBERG
- Heart Research Follow-up Program; University of Rochester School of Medicine & Dentistry; Rochester New York
| | - YASH SHAH
- Heart Research Follow-up Program; University of Rochester School of Medicine & Dentistry; Rochester New York
| | - BARBARA SZEPIETOWSKA
- Heart Research Follow-up Program; University of Rochester School of Medicine & Dentistry; Rochester New York
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16
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Dale KM, White CM. Dronedarone: An Amiodarone Analog for the Treatment of Atrial Fibrillation and Atrial Flutter. Ann Pharmacother 2016; 41:599-605. [PMID: 17389667 DOI: 10.1345/aph.1h524] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Objective: To review the pharmacology, pharmacokinetics, clinical efficacy, and safety profile of dronedarone for the treatment of atrial fibrillation. Data Sources: A literature search was conducted using the search terms dronedarone, SR 33589, atrial fibrillation, and antiarrhythmic medication in MEDLINE (1966–February 2007), International Pharmaceutical Abstracts (1970–February 2007), and EMBASE (1990–February 2007). References from the identified trials and selected review articles were evaluated. Additional information, including abstracts and posters, was obtained from Sanofi-Aventis. Study Selection and Data Extraction: Published studies and meeting abstracts evaluating the effects of dronedarone in humans and animals were reviewed. Data Synthesis: Dronedarone is a novel antiarrhythmic medication to treat atrial fibrillation. Dronedarone has a multifaceted mechanism of action similar to that of amiodarone. Dronedarone works by blocking potassium, sodium, and calcium channels and exhibits antiadrenergic properties. The drug has been evaluated at doses of 400, 600, and 800 mg twice daily. It prolonged the time to atrial fibrillation recurrence to 60–158 days compared with 5–59 days with placebo and decreased heart rate during atrial fibrillation by 12–25 beats/min in clinical trials. Major adverse events include gastrointestinal side effects and risk of proarrhythmia. Dronedarone may increase the risk of mortality in patients with congestive heart failure. Conclusions: Dronedarone is a new antiarrhythmic agent for the treatment of atrial fibrillation. Further studies are needed to better define dronedarone's safety profile and place in therapy.
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Affiliation(s)
- Krista M Dale
- School of Pharmacy, University of Connecticut, Hartford, CT, USA
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17
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Chiang CE, Wu TJ, Ueng KC, Chao TF, Chang KC, Wang CC, Lin YJ, Yin WH, Kuo JY, Lin WS, Tsai CT, Liu YB, Lee KT, Lin LJ, Lin LY, Wang KL, Chen YJ, Chen MC, Cheng CC, Wen MS, Chen WJ, Chen JH, Lai WT, Chiou CW, Lin JL, Yeh SJ, Chen SA. 2016 Guidelines of the Taiwan Heart Rhythm Society and the Taiwan Society of Cardiology for the management of atrial fibrillation. J Formos Med Assoc 2016; 115:893-952. [PMID: 27890386 DOI: 10.1016/j.jfma.2016.10.005] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 08/24/2016] [Accepted: 10/10/2016] [Indexed: 12/21/2022] Open
Abstract
Atrial fibrillation (AF) is the most common sustained arrhythmia. Both the incidence and prevalence of AF are increasing, and the burden of AF is becoming huge. Many innovative advances have emerged in the past decade for the diagnosis and management of AF, including a new scoring system for the prediction of stroke and bleeding events, the introduction of non-vitamin K antagonist oral anticoagulants and their special benefits in Asians, new rhythm- and rate-control concepts, optimal endpoints of rate control, upstream therapy, life-style modification to prevent AF recurrence, and new ablation techniques. The Taiwan Heart Rhythm Society and the Taiwan Society of Cardiology aimed to update the information and have appointed a jointed writing committee for new AF guidelines. The writing committee members comprehensively reviewed and summarized the literature, and completed the 2016 Guidelines of the Taiwan Heart Rhythm Society and the Taiwan Society of Cardiology for the Management of Atrial Fibrillation. This guideline presents the details of the updated recommendations, along with their background and rationale, focusing on data unique for Asians. The guidelines are not mandatory, and members of the writing committee fully realize that treatment of AF should be individualized. The physician's decision remains most important in AF management.
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Affiliation(s)
- Chern-En Chiang
- General Clinical Research Center, Division of Cardiology, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan.
| | - Tsu-Juey Wu
- Cardiovascular Center, Department of Internal Medicine, Taichung Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan
| | - Kwo-Chang Ueng
- Department of Internal Medicine, School of Medicine, Chung-Shan Medical University (Hospital), Taichung, Taiwan
| | - Tze-Fan Chao
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Kuan-Cheng Chang
- Division of Cardiology, Department of Medicine, China Medical University Hospital, Taichung, Taiwan; Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan
| | - Chun-Chieh Wang
- Department of Internal Medicine, Section of Cardiology, Chang Gung University College of Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Yenn-Jiang Lin
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Wei-Hsian Yin
- Heart Center, Cheng Hsin General Hospital, Taipei, Taiwan; Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Jen-Yuan Kuo
- Division of Cardiology, Department of Internal Medicine, MacKay Memorial Hospital, Taipei, Taiwan; Department of Medicine, Mackay Medical College, Taipei, Taiwan
| | - Wei-Shiang Lin
- Division of Cardiology, Tri-Service General Hospital and National Defense Medical Center, Taipei, Taiwan
| | - Chia-Ti Tsai
- Division of Cardiology, Department of Internal Medicine, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan
| | - Yen-Bin Liu
- Division of Cardiology, Department of Internal Medicine, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan; Division of Cardiology, National Taiwan University Hospital Hsin-Chu Branch, Hsin-Chu, Taiwan
| | - Kun-Tai Lee
- Division of Cardiology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Department of Internal Medicine, Faculty of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Li-Jen Lin
- Department of Internal Medicine, National Cheng Kung University College of Medicine and Hospital, Tainan, Taiwan
| | - Lian-Yu Lin
- Division of Cardiology, Department of Internal Medicine, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan
| | - Kang-Ling Wang
- General Clinical Research Center, Division of Cardiology, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan
| | - Yi-Jen Chen
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Mien-Cheng Chen
- Division of Cardiology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | | | - Ming-Shien Wen
- Department of Internal Medicine, Section of Cardiology, Chang Gung University College of Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Wen-Jone Chen
- Division of Cardiology, Department of Internal Medicine, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan; Division of Cardiology, Poh-Ai Hospital, Yilan, Taiwan
| | - Jyh-Hong Chen
- Department of Internal Medicine, National Cheng Kung University College of Medicine and Hospital, Tainan, Taiwan; College of Medicine, China Medical University, Taichung, Taiwan
| | - Wen-Ter Lai
- Division of Cardiology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Department of Internal Medicine, Faculty of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chuen-Wang Chiou
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Jiunn-Lee Lin
- Division of Cardiology, Department of Internal Medicine, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan
| | - San-Jou Yeh
- Department of Internal Medicine, Section of Cardiology, Chang Gung University College of Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
| | - Shih-Ann Chen
- Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan.
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18
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Perindopril for the prevention of atrial fibrillation recurrence after radiofrequency catheter ablation: One-year experience. Heart Rhythm 2016; 13:2040-7. [DOI: 10.1016/j.hrthm.2016.06.039] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Indexed: 11/21/2022]
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19
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Dorian P, Mangat I, Pinter A, Korley V. The Burden of Atrial Fibrillation: Should We Abandon Antiarrhythmic Drug Therapy? J Cardiovasc Pharmacol Ther 2016; 9:257-62. [PMID: 15678244 DOI: 10.1177/107424840400900405] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Atrial fibrillation (AF) is the most common sustained arrhythmia, exacting a substantial toll in cardiovascular morbidity and mortality. Until recently, the prevailing philosophy has been that restoration and maintenance of normal sinus rhythm, as opposed to control of ventricular response rate, was the optimal approach to treatment of AF. A series of landmark trials (AFFIRM, RACE, STAF, and PIAF) have called this strategy into question, suggesting outcomes are equivalent with both approaches. These data do not mean that rhythm control is not beneficial, but highlight the limitations of current therapies to achieve and maintain sinus rhythm. Limitations of the rhythm-control strategy may be related to our difficulty in accurately documenting symptomatic benefit from this approach, the lack of efficacy and excessive adverse-effect burden associated with currently available antiarrhythmic agents, and selection biases in the enrollment of patients in clinical trials of rhythm control versus rate control, making the trials incompletely representative of the population eligible for therapy. New pharmacologic agents under development feature increased atrial selectivity or multi-channel-blocking properties (or both). As a result, these compounds may be more effective in prolonging atrial refractoriness and may also have reduced proarrhythmic potential. It is premature to abandon the concept of rhythm control in AF until we have trials designed to include younger and highly symptomatic patients, more sensitive tools to measure symptomatic improvement, and safer, more effective antiarrhythmic agents.
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Affiliation(s)
- Paul Dorian
- Division of Cardiology, Department of Medicine, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.
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20
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Xu X, Alida CT, Yu B. Administration of antiarrhythmic drugs to maintain sinus rhythm after catheter ablation for atrial fibrillation: a meta-analysis. Cardiovasc Ther 2016; 33:242-6. [PMID: 26031448 DOI: 10.1111/1755-5922.12133] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Whether the short-term administration of antiarrhythmic drugs (AADs) to maintain sinus rhythm following catheter ablation (CA) for atrial fibrillation (AF) can prevent the recurrence of AF is still a matter of debate. We searched the PubMed database and the Cochrane Library, and compiled a list of retrieved articles. We included only randomised controlled trials(RCTs) that compared any AADs against control (placebo or no treatment) or other AADs following CA for AF. Statistical analysis of the odds ratio (OR) and corresponding 95% confidence interval (CI) were used to determine the overall effect of both outcomes. The Mantel-Haenszel method was used to pool data of the outcomes of AF recurrence into fixed effect model meta-analyses. AIMS We performed a systematic review to determine the effectiveness of short-term treatment with AADs on the recurrence of AF after CA. RESULTS Six RCTs were included in this study, with a total of 814 patients. Post-procedural temporary administration of AADs in patients after CA for AF reduced the early recurrence of AF (antiarrhythmic drug 103 patients [25.3%], control 162 patients [39.8%]; OR 0.47 [95% CI 0.34-0.64]; χ(2) = 3.77; P = 0.58; I(2) = 0%). No significant difference in patients after CA for AF in the late recurrence of AF (antiarrhythmic drug 148 patients [36.5%], control 171 patients [42.5%]; OR 0.77 [95% CI 0.57-1.03]; χ(2) = 3.15; P = 0.68; I(2) = 0%). The heterogeneity was zero in both analyses. CONCLUSION Although the continued administration of AADs after CA for AF can decrease early atrial tachycardias (ATa), this treatment does not prevent late ATa.
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Affiliation(s)
- Xiuli Xu
- Department of Cardiology, The First Hospital Affiliated to China Medical University, Shenyang, Liaoning, China
| | - Choumi T Alida
- Department of Cardiology, The First Hospital Affiliated to China Medical University, Shenyang, Liaoning, China
| | - Bo Yu
- Department of Cardiology, The First Hospital Affiliated to China Medical University, Shenyang, Liaoning, China
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21
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Hu D, Barajas-Martínez H, Burashnikov A, Panama BK, Cordeiro JM, Antzelevitch C. Mechanisms underlying atrial-selective block of sodium channels by Wenxin Keli: Experimental and theoretical analysis. Int J Cardiol 2016; 207:326-34. [PMID: 26820362 DOI: 10.1016/j.ijcard.2016.01.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 12/29/2015] [Accepted: 01/01/2016] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Atrial-selective inhibition of cardiac sodium channel current (INa) and INa-dependent parameters has been shown to contribute to the safe and effective management of atrial fibrillation. The present study was designed to examine the basis for the atrial-selective actions of Wenxin Keli. METHODS Whole cell INa was recorded at room temperature in canine atrial and ventricular myocytes. Trains of 40 pulses were elicited over a range of pulse durations and interpulse intervals to determine tonic and use-dependent block. A Markovian model for INa that incorporates interaction of Wenxin Keli with different states of the channel was developed to examine the basis for atrial selectivity of the drug. RESULTS Our data indicate that Wenxin Keli does not bind significantly to either closed or open states of the sodium channel, but binds very rapidly to the inactivated state of the channel and dissociates rapidly from the closed state. Action potentials recorded from atrial and ventricular preparations in the presence of 5g/L Wenxin Keli were introduced into the computer model in current clamp mode to simulate the effects on maximum upstroke velocity (Vmax). The model predicted much greater inhibition of Vmax in atrial vs. ventricular cells at rapid stimulation rates. CONCLUSION Our findings suggest that atrial selectivity of Wenxin Keli to block INa is due to more negative steady-state inactivation, less negative resting membrane potential, and shorter diastolic intervals in atrial vs. ventricular cells at rapid activation rates. These actions of Wenxin Keli account for its relatively safe and effective suppression of atrial fibrillation.
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Affiliation(s)
- Dan Hu
- Masonic Medical Research Laboratory, Utica, NY, United States
| | | | | | - Brian K Panama
- Masonic Medical Research Laboratory, Utica, NY, United States
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22
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Lenhoff H, Darpö B, Ferber G, Rosenqvist M, Frick M. Reduction over time of QTc prolongation in patients with sotalol after cardioversion of atrial fibrillation. Heart Rhythm 2015; 13:661-8. [PMID: 26654918 DOI: 10.1016/j.hrthm.2015.11.040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Indexed: 11/24/2022]
Abstract
BACKGROUND Sotalol is recommended to prevent relapse of atrial fibrillation after cardioversion (CV). Sotalol prolongs the action potential by blocking the rapid component of the delayed rectifier potassium current, which results in corrected QT (QTc) prolongation on the electrocardiogram. Pronounced QTc prolongation may lead to proarrhythmias and sudden death. OBJECTIVE We investigated the dynamics of the QTc interval during the week after CV in patients treated with sotalol compared with patients treated with a β-blocker. METHODS Patients who underwent elective CV for persistent atrial fibrillation and maintained sinus rhythm for 1 week were included prospectively. All patients were on the highest tolerable stable dose of metoprolol or sotalol. Twelve-lead electrocardiograms were recorded 1 hour and 1 week after CV. RESULTS A total of 104 patients on sotalol and 104 on metoprolol were included; clinical characteristics between groups were comparable. One hour after CV, the QTc interval was significantly longer in sotalol-treated patients than in metoprolol-treated patients (465 ± 25 ms vs 423 ± 30 ms; P ≤ .0001). After 1 week, the QTc interval was reduced by -20.3 ± 24 ms in sotalol-treated patients (P ≤ .001); no such effect was seen in metoprolol-treated patients (-2.5 ± 18 ms; P = 0.28). The heart rate was stable during the week in both groups. In multivariate analysis of sotalol-treated patients, factors contributing to pronounced reduction in the QTc interval were longer QTc interval after CV and renal function. CONCLUSION The QTc interval is significantly reduced during the week after CV to sinus rhythm in sotalol-treated patients. This provides insight into the increased risk of proarrhythmias in the immediate time period after CV.
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Affiliation(s)
- Hanna Lenhoff
- Department of Clinical Science and Education, Division of Cardiology, Karolinska Institute, South Hospital, Stockholm, Sweden.
| | - Börje Darpö
- Statistik Georg Ferber GmbH, Riehen, Switzerland
| | - Georg Ferber
- Statistik Georg Ferber GmbH, Riehen, Switzerland
| | - Mårten Rosenqvist
- Department of Clinical Sciences, Karolinska Institute, Danderyd Hospital, Stockholm, Sweden
| | - Mats Frick
- Department of Clinical Science and Education, Division of Cardiology, Karolinska Institute, South Hospital, Stockholm, Sweden
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23
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Reiffel JA, Camm AJ, Belardinelli L, Zeng D, Karwatowska-Prokopczuk E, Olmsted A, Zareba W, Rosero S, Kowey P. The HARMONY Trial: Combined Ranolazine and Dronedarone in the Management of Paroxysmal Atrial Fibrillation: Mechanistic and Therapeutic Synergism. Circ Arrhythm Electrophysiol 2015; 8:1048-56. [PMID: 26226999 DOI: 10.1161/circep.115.002856] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 07/09/2015] [Indexed: 12/13/2022]
Abstract
BACKGROUND Atrial fibrillation (AF) requires arrhythmogenic changes in atrial ion channels/receptors and usually altered atrial structure. AF is commonly treated with antiarrhythmic drugs; the most effective block many ion channels/receptors. Modest efficacy, intolerance, and safety concerns limit current antiarrhythmic drugs. We hypothesized that combining agents with multiple anti-AF mechanisms at reduced individual drug doses might produce synergistic efficacy plus better tolerance/safety. METHODS AND RESULTS HARMONY tested midrange ranolazine (750 mg BID) combined with 2 reduced dronedarone doses (150 mg BID and 225 mg BID; chosen to reduce dronedarone's negative inotropic effect-see text below) over 12 weeks in 134 patients with paroxysmal AF and implanted pacemakers where AF burden (AFB) could be continuously assessed. Patients were randomized double-blind to placebo, ranolazine alone (750 mg BID), dronedarone alone (225 mg BID), or one of the combinations. Neither placebo nor either drugs alone significantly reduced AFB. Conversely, ranolazine 750 mg BID/dronedarone 225 mg BID reduced AFB by 59% versus placebo (P=0.008), whereas ranolazine 750 mg BID/dronedarone 150 mg BID reduced AFB by 43% (P=0.072). Both combinations were well tolerated. CONCLUSIONS HARMONY showed synergistic AFB reduction by moderate dose ranolazine plus reduced dose dronedarone, with good tolerance/safety, in the population enrolled. CLINICAL TRIAL REGISTRATION ClinicalTrials.gov; Unique identifier: NCT01522651.
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Affiliation(s)
- James A Reiffel
- From the Division of Cardiology, Department of Medicine, Columbia University, New York, NY (J.A.R.); Department of Cardiovascular Sciences, St Georges University of London, London, United Kingdom (A.J.C.); Cardiovascular Clinical Research, Gilead Sciences, Inc, Foster City, CA (L.B., D.Z., E.K.-P., A.O.); Division of Cardiology, Department of Medicine, University of Rochester Medical Center, NY (W.Z., S.R.); Lankenau Institute for Medical Research, Wynnewood, PA (P.K.); and Division of Cardiovascular Diseases, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (P.K.).
| | - A John Camm
- From the Division of Cardiology, Department of Medicine, Columbia University, New York, NY (J.A.R.); Department of Cardiovascular Sciences, St Georges University of London, London, United Kingdom (A.J.C.); Cardiovascular Clinical Research, Gilead Sciences, Inc, Foster City, CA (L.B., D.Z., E.K.-P., A.O.); Division of Cardiology, Department of Medicine, University of Rochester Medical Center, NY (W.Z., S.R.); Lankenau Institute for Medical Research, Wynnewood, PA (P.K.); and Division of Cardiovascular Diseases, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (P.K.)
| | - Luiz Belardinelli
- From the Division of Cardiology, Department of Medicine, Columbia University, New York, NY (J.A.R.); Department of Cardiovascular Sciences, St Georges University of London, London, United Kingdom (A.J.C.); Cardiovascular Clinical Research, Gilead Sciences, Inc, Foster City, CA (L.B., D.Z., E.K.-P., A.O.); Division of Cardiology, Department of Medicine, University of Rochester Medical Center, NY (W.Z., S.R.); Lankenau Institute for Medical Research, Wynnewood, PA (P.K.); and Division of Cardiovascular Diseases, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (P.K.)
| | - Dewan Zeng
- From the Division of Cardiology, Department of Medicine, Columbia University, New York, NY (J.A.R.); Department of Cardiovascular Sciences, St Georges University of London, London, United Kingdom (A.J.C.); Cardiovascular Clinical Research, Gilead Sciences, Inc, Foster City, CA (L.B., D.Z., E.K.-P., A.O.); Division of Cardiology, Department of Medicine, University of Rochester Medical Center, NY (W.Z., S.R.); Lankenau Institute for Medical Research, Wynnewood, PA (P.K.); and Division of Cardiovascular Diseases, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (P.K.)
| | - Ewa Karwatowska-Prokopczuk
- From the Division of Cardiology, Department of Medicine, Columbia University, New York, NY (J.A.R.); Department of Cardiovascular Sciences, St Georges University of London, London, United Kingdom (A.J.C.); Cardiovascular Clinical Research, Gilead Sciences, Inc, Foster City, CA (L.B., D.Z., E.K.-P., A.O.); Division of Cardiology, Department of Medicine, University of Rochester Medical Center, NY (W.Z., S.R.); Lankenau Institute for Medical Research, Wynnewood, PA (P.K.); and Division of Cardiovascular Diseases, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (P.K.)
| | - Ann Olmsted
- From the Division of Cardiology, Department of Medicine, Columbia University, New York, NY (J.A.R.); Department of Cardiovascular Sciences, St Georges University of London, London, United Kingdom (A.J.C.); Cardiovascular Clinical Research, Gilead Sciences, Inc, Foster City, CA (L.B., D.Z., E.K.-P., A.O.); Division of Cardiology, Department of Medicine, University of Rochester Medical Center, NY (W.Z., S.R.); Lankenau Institute for Medical Research, Wynnewood, PA (P.K.); and Division of Cardiovascular Diseases, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (P.K.)
| | - Wojciech Zareba
- From the Division of Cardiology, Department of Medicine, Columbia University, New York, NY (J.A.R.); Department of Cardiovascular Sciences, St Georges University of London, London, United Kingdom (A.J.C.); Cardiovascular Clinical Research, Gilead Sciences, Inc, Foster City, CA (L.B., D.Z., E.K.-P., A.O.); Division of Cardiology, Department of Medicine, University of Rochester Medical Center, NY (W.Z., S.R.); Lankenau Institute for Medical Research, Wynnewood, PA (P.K.); and Division of Cardiovascular Diseases, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (P.K.)
| | - Spencer Rosero
- From the Division of Cardiology, Department of Medicine, Columbia University, New York, NY (J.A.R.); Department of Cardiovascular Sciences, St Georges University of London, London, United Kingdom (A.J.C.); Cardiovascular Clinical Research, Gilead Sciences, Inc, Foster City, CA (L.B., D.Z., E.K.-P., A.O.); Division of Cardiology, Department of Medicine, University of Rochester Medical Center, NY (W.Z., S.R.); Lankenau Institute for Medical Research, Wynnewood, PA (P.K.); and Division of Cardiovascular Diseases, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (P.K.)
| | - Peter Kowey
- From the Division of Cardiology, Department of Medicine, Columbia University, New York, NY (J.A.R.); Department of Cardiovascular Sciences, St Georges University of London, London, United Kingdom (A.J.C.); Cardiovascular Clinical Research, Gilead Sciences, Inc, Foster City, CA (L.B., D.Z., E.K.-P., A.O.); Division of Cardiology, Department of Medicine, University of Rochester Medical Center, NY (W.Z., S.R.); Lankenau Institute for Medical Research, Wynnewood, PA (P.K.); and Division of Cardiovascular Diseases, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (P.K.)
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Bhatt HV, Fischer GW. Atrial Fibrillation: Pathophysiology and Therapeutic Options. J Cardiothorac Vasc Anesth 2015; 29:1333-40. [PMID: 26384632 DOI: 10.1053/j.jvca.2015.05.058] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Indexed: 11/11/2022]
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Kudenchuk PJ. New approaches to managing nonvalvular atrial fibrillation: what are the thromboembolic implications? J Thromb Thrombolysis 2015; 39:345-52. [DOI: 10.1007/s11239-015-1181-y] [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: 10/24/2022]
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Bhatty S, Saliaris AP. Atrial fibrillation ablation in the era of cryoballoon and force-sensing catheters: freeze or burn? CURRENT TREATMENT OPTIONS IN CARDIOVASCULAR MEDICINE 2015; 17:374. [PMID: 25791081 DOI: 10.1007/s11936-015-0374-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OPINION STATEMENT Atrial fibrillation can adversely affect the quality of life for many patients. Though antiarrhythmic drug therapy remains an option for the treatment of atrial fibrillation, the drugs are associated with numerous side effects. Atrial fibrillation ablation has been shown to be as efficacious as antiarrhythmic drug therapy. The field of atrial fibrillation ablations has evolved over time from utilizing radiofrequency energy to using cryoenergy. Newer technologies are being developed with efforts to improve outcomes in patients undergoing atrial fibrillation ablations. This article will highlight two such technologies: cryoballoon ablation catheters and contact force-sensing catheters. These novel catheters appear to be further revolutionizing this young field in electrophysiology.
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Affiliation(s)
- Shaun Bhatty
- University of Maryland Medical Center, 22 South Greene Street, Baltimore, MD, 21201, USA,
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Gibson JK, Yue Y, Bronson J, Palmer C, Numann R. Human stem cell-derived cardiomyocytes detect drug-mediated changes in action potentials and ion currents. J Pharmacol Toxicol Methods 2014; 70:255-67. [DOI: 10.1016/j.vascn.2014.09.005] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 09/02/2014] [Accepted: 09/04/2014] [Indexed: 10/24/2022]
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Atrial fibrillation in a large population with Brugada electrocardiographic pattern: prevalence, management, and correlation with prognosis. Heart Rhythm 2014; 11:259-65. [PMID: 24513919 DOI: 10.1016/j.hrthm.2013.10.043] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Indexed: 01/08/2023]
Abstract
BACKGROUND A high prevalence of atrial fibrillation/atrial flutter (AF/AFl) has been reported in small series of Brugada patients, with discordant data. OBJECTIVE The purpose of this study was to analyze, in a large population of Brugada patients, the prevalence of AF/AFl, its correlation with prognosis, and the efficacy of hydroquinidine (HQ) treatment. METHODS Among 560 patients with Brugada type 1 ECG (BrECG), 48 (9%) had AF/AFl. Three groups were considered: 23 patients with BrECG pattern recognized before AF/AFl (group 1); 25 patients first diagnosed with AF/AFl in whom Class IC antiarrhythmic drugs administered for cardioversion/prophylaxis unmasked BrECG (group 2); and 512 patients without AF/AFl (group 3). Recurrence of AF/AFl and occurrence of ventricular arrhythmias were evaluated at follow-up. RESULTS Mean age was 47 ± 15 years, 59 ± 11 years, and 44 ± 14 years in groups 1, 2, and 3, respectively. Seven subjects (32%) in group 1 had syncope/aborted sudden death, 1 (4%) in group 2, and 122 (24%) in group 3. Ventricular arrhythmia occurred in three patients in group 1, none in group 2, and 10 in group 3 at median follow-up of 51, 68, and 41 months, respectively. Nine patients in group 1 and nine in group 2 received HQ for AF/AFl prophylaxis; on therapy, none had AF/AFl recurrence. CONCLUSION Prevalence of AF/AFl in Brugada patients is higher than in the general population of the same age. Patients in group 1 are younger than those in group 2 and have a worse prognosis compared to both groups 2 and 3. HQ therapy has proved useful and safe in patients with AF/AFl and BrECG.
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Abstract
In a normal human life span, the heart beats about 2 to 3 billion times. Under diseased conditions, a heart may lose its normal rhythm and degenerate suddenly into much faster and irregular rhythms, called arrhythmias, which may lead to sudden death. The transition from a normal rhythm to an arrhythmia is a transition from regular electrical wave conduction to irregular or turbulent wave conduction in the heart, and thus this medical problem is also a problem of physics and mathematics. In the last century, clinical, experimental, and theoretical studies have shown that dynamical theories play fundamental roles in understanding the mechanisms of the genesis of the normal heart rhythm as well as lethal arrhythmias. In this article, we summarize in detail the nonlinear and stochastic dynamics occurring in the heart and their links to normal cardiac functions and arrhythmias, providing a holistic view through integrating dynamics from the molecular (microscopic) scale, to the organelle (mesoscopic) scale, to the cellular, tissue, and organ (macroscopic) scales. We discuss what existing problems and challenges are waiting to be solved and how multi-scale mathematical modeling and nonlinear dynamics may be helpful for solving these problems.
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Affiliation(s)
- Zhilin Qu
- Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA
- Correspondence to: Zhilin Qu, PhD, Department of Medicine, Division of Cardiology, David Geffen School of Medicine at UCLA, A2-237 CHS, 650 Charles E. Young Drive South, Los Angeles, CA 90095, Tel: 310-794-6050, Fax: 310-206-9133,
| | - Gang Hu
- Department of Physics, Beijing Normal University, Beijing 100875, China
| | - Alan Garfinkel
- Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA
- Department of Integrative Biology and Physiology, University of California, Los Angeles, California 90095, USA
| | - James N. Weiss
- Department of Medicine (Cardiology), David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA
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Wasmer K, Breithardt G, Eckardt L. The young patient with asymptomatic atrial fibrillation: what is the evidence to leave the arrhythmia untreated? Eur Heart J 2014; 35:1439-47. [DOI: 10.1093/eurheartj/ehu113] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Desai AM, Cavanaugh TM, Desai VCA, Heaton PC, Kelton CML. Trends in the outpatient treatment of atrial fibrillation in the USA from 2001 to 2010. Pharmacoepidemiol Drug Saf 2014; 23:539-47. [DOI: 10.1002/pds.3605] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 01/29/2014] [Accepted: 02/03/2014] [Indexed: 01/29/2023]
Affiliation(s)
- Amarsinh M. Desai
- James L. Winkle College of Pharmacy; University of Cincinnati Academic Health Center; Cincinnati OH 45267 USA
| | - Teresa M. Cavanaugh
- James L. Winkle College of Pharmacy; University of Cincinnati Academic Health Center; Cincinnati OH 45267 USA
| | - Vibha C. A. Desai
- James L. Winkle College of Pharmacy; University of Cincinnati Academic Health Center; Cincinnati OH 45267 USA
| | - Pamela C. Heaton
- James L. Winkle College of Pharmacy; University of Cincinnati Academic Health Center; Cincinnati OH 45267 USA
| | - Christina M. L. Kelton
- James L. Winkle College of Pharmacy; University of Cincinnati Academic Health Center; Cincinnati OH 45267 USA
- Carl H. Lindner College of Business; University of Cincinnati; Cincinnati OH 45221 USA
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Motonaga KS, Khairy P, Dubin AM. Electrophysiologic Therapeutics in Heart Failure in Adult Congenital Heart Disease. Heart Fail Clin 2014; 10:69-89. [DOI: 10.1016/j.hfc.2013.09.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Long-term prognostic value of dysglycemia and ischemic vascular disease beyond abnormal troponin levels in patients presenting acute atrial fibrillation. Crit Pathw Cardiol 2013; 12:14-23. [PMID: 23411603 DOI: 10.1097/hpc.0b013e31827f120b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Prognostication beyond troponin levels in patients with acute atrial fibrillation (AF) is still unclear. METHODS One-month and 1-year outcomes in 1091 patients with acute AF were analyzed. Primary endpoints were stroke or the composite of acute coronary syndrome, revascularization, and death. RESULTS In the short term, troponin (odds ratio (OR) 15, 95% confidence interval (CI), 3.4-67.9, P < 0.001) and known ischemic heart disease (OR 5.83, 95% CI, 1.3-26.2, P = 0.021) were predictors of the composite endpoint, with multivariate analysis. No variables linked with stroke. In the long term, metabolic syndrome (OR 4.7, 95% CI, 1.2-18.3, P = 0.024) and age (OR 1.1, 95% CI, 1.0-1.1, P = 0.009) were predictors of stroke; metabolic syndrome (OR 4.3, 95% CI, 1.6-11.0, P = 0.003), known ischemic heart disease (OR 3.3, 95% CI, 1.7-6.4, P = 0.001), persistence of AF after the first-line approach (OR 2.2, 95% CI, 1.2-4.3, P = 0.018), and age (OR 1.0, 95% CI, 1.0-1.1, P = 0.025), but not troponin so were of the composite endpoint. In the short term, increased discriminative values in prognostication of the composite endpoint were observed with C-statistic when troponin was compared with dysglycemia (P = 0.032). No variables did better than others in the prognostication of stroke. In the long term, increased discriminative values in the prognostication of stroke were observed with C-statistic when age was compared with troponin (P = 0.020), ischemic heart disease (P = 0.025), and persistence of AF after the first-line approach (P = 0.049); so was for CHADS2 score ≥1 versus vascular disease (P = 0.038). CONCLUSIONS In patients with acute AF, abnormal troponin levels add prognostic value to clinical parameters in the short term; dysglycemia and known vascular disease in the long term.
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Abstract
Bradyarrhythmias and tachyarrhythmias are common in elderly patients as a result of aging and acquired cardiac disease. Antiarrhythmic drugs are effective in elderly patients for the management of supraventricular and ventricular arrhythmias; however, dosing of drugs must be performed with care because of age-related changes in drug pharmacokinetics, the presence of concomitant disease, and frequent drug-drug interactions. Despite the large number of antiarrhythmic drugs having different electrophysiologic actions, as described in this article, only the β-blockers have been shown to be effective in reducing mortality and to lack proarrhythmic actions.
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Conti A, Canuti E, Mariannini Y, Viviani G, Poggioni C, Boni V, Pini R, Vanni S, Padeletti L, Gensini GF. Clinical management of atrial fibrillation: early interventions, observation, and structured follow-up reduce hospitalizations. Am J Emerg Med 2012; 30:1962-9. [DOI: 10.1016/j.ajem.2012.04.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 03/08/2012] [Accepted: 04/17/2012] [Indexed: 12/19/2022] Open
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Shteinshnaider M, Almoznino-Sarafian D, Alon I, Tzur I, Berman S, Cohen N, Gorelik O. Atrial Fibrillation at an Internal Medicine Ward: Clinical and Prognostic Implications. J Atr Fibrillation 2012; 5:343. [PMID: 28496740 DOI: 10.4022/jafib.343] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 11/17/2012] [Accepted: 01/04/2012] [Indexed: 01/01/2023]
Abstract
Background: Little is known about atrial fibrillation (AF) appearing during hospitalization in an Internal Medicine ward. Purpose: We aimed to investigate characteristics and prognostic significance of in-hospital onset AF. Methods: We studied 249 consecutive unselected patients admitted to this medical department with paroxysmal or persistent AF (out-of-hospital group) or AF developed during hospitalization (in-hospital group). Demographic, clinical, laboratory, electrocardiographic and echocardiographic data and all-cause mortality following discharge were recorded and compared between the groups Results: Diabetes mellitus (p=0.05), renal dysfunction (p<0.001), chronic lung disease (p=0.03) and history of stroke (p=0.01) were found more common in the in-hospital group (56 patients), compared to the out-of-hospital group (193 patients). Patients from the in-hospital group were more likely to have recurrent episodes of AF during hospitalization (p=0.002), were more frequently treated with amiodarone (p<0.001), discharged in sinus rhythm (p=0.04) and with medications for rhythm control (p=0.04). Time from onset to termination of AF (p<0.001) and hospital stay (p<0.001) were longer in the in-hospital group. On a median of 39-months follow-up, survival rate was lower in the in-hospital vs. out-of-hospital group (69.6% vs. 81.3%, p=0.025). Older age was significantly associated with shorter survival in the in-hospital group [odds ratio (OR)=1.87, 95% confidence interval (CI) 1.15-3.03, p=0.009]. In the out-of-hospital group, advanced age (OR=2.17, 95%CI 1.51-3.10, p<0.001), no prior AF episode (OR=3.41, 95%CI 1.56-7.46, p=0.002), diabetes mellitus (OR=2.22, 95%CI 1.12-4.39, p=0.006) and renal dysfunction (OR=2.44, 95%CI 1.10-5.38, p=0.049) were significantly associated with shorter survival. Conclusion: Patients developing in-hospital AF differed from subjects hospitalized for AF with respect to the severity of the clinical profile and prognosis.
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Affiliation(s)
| | | | | | | | - Sylvia Berman
- Research & Development Division and Department of Nephrology, Assaf Harofeh Medical Center (affiliated to Sackler School of Medicine, Tel Aviv University), Zerifin, Israel
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Abstract
Flecainide is a class Ic antiarrhythmic agent that has an important role as part of rhythm control strategies in patients with atrial fibrillation (AF). Early clinical data on the use of flecainide showed an increase in arrhythmias and mortality compared with placebo in patients with a previous myocardial infarction and asymptomatic or mildly symptomatic ventricular arrhythmias. These findings only apply to a specific group of patients with left ventricular dysfunction and ischaemic heart disease, but had a negative impact on the use of class Ic antiarrhythmics across all indications and patient groups. The aim of this review was to evaluate the available safety data for flecainide in the literature and to assess its current use in patients with AF. Current European guidelines now recommend the use of flecainide in carefully selected groups of patients with AF who do not have structural heart disease. This includes for the cardioversion of recent-onset AF, pretreatment prior to direct current cardioversion, out-of-hospital acute oral therapy ('pill-in-the-pocket' approach) and for the ongoing maintenance of sinus rhythm. Potential cardiac adverse effects of flecainide include proarrhythmia, conduction abnormalities and negative inotropic effects. Dizziness is the most frequent non-cardiac side effect, followed by blurred vision and difficulty focusing; these are almost all mild, transient and tolerable. Data from recent clinical trials in patients with supraventricular arrhythmias suggest that flecainide has a good tolerability profile in groups of appropriately selected patients. Caution is required when using flecainide in patients with renal dysfunction, and there are a number of drug interactions, but these are well documented and manageable. Overall, flecainide is a good choice for the pharmacological management of AF. It has a good safety record and low incidence of adverse effects, rare end-organ toxicity and a low risk of ventricular proarrhythmia. To ensure that the benefits of treatment outweigh any potential risks, careful patient selection and monitoring is required.
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Affiliation(s)
- Juan Tamargo
- Department of Pharmacology, School of Medicine, Universidad Complutense, Madrid, Spain.
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Bapat A, Nguyen TP, Lee JH, Sovari AA, Fishbein MC, Weiss JN, Karagueuzian HS. Enhanced sensitivity of aged fibrotic hearts to angiotensin II- and hypokalemia-induced early afterdepolarization-mediated ventricular arrhythmias. Am J Physiol Heart Circ Physiol 2012; 302:H2331-40. [PMID: 22467308 DOI: 10.1152/ajpheart.00094.2012] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Unlike young hearts, aged hearts are highly susceptible to early afterdepolarization (EAD)-mediated ventricular fibrillation (VF). This differential may result from age-related structural remodeling (fibrosis) or electrical remodeling of ventricular myocytes or both. We used optical mapping and microelectrode recordings in Langendorff-perfused hearts and patch-clamp recordings in isolated ventricular myocytes from aged (24-26 mo) and young (3-4 mo) rats to assess susceptibility to EADs and VF during either oxidative stress with ANG II (2 μM) or ionic stress with hypokalemia (2.7 mM). ANG II caused EAD-mediated VF in 16 of 19 aged hearts (83%) after 32 ± 7 min but in 0 of 9 young hearts (0%). ANG II-mediated VF was suppressed with KN-93 (Ca(2+)/calmodulin-dependent kinase inhibitor) and the reducing agent N-acetylcysteine. Hypokalemia caused EAD-mediated VF in 11 of 11 aged hearts (100%) after 7.4 ± 0.4 min. In 14 young hearts, however, VF did not occur in 6 hearts (43%) or was delayed in onset (31 ± 22 min, P < 0.05) in 8 hearts (57%). In patch-clamped myocytes, ANG II and hypokalemia (n = 6) induced EADs and triggered activity in both age groups (P = not significant) at a cycle length of >0.5 s. When myocytes of either age group were coupled to a virtual fibroblast using the dynamic patch-clamp technique, EADs arose in both groups at a cycle length of <0.5 s. Aged ventricles had significantly greater fibrosis and reduced connexin43 gap junction density compared with young hearts. The lack of differential age-related sensitivity at the single cell level in EAD susceptibility indicates that increased ventricular fibrosis in the aged heart plays a key role in increasing vulnerability to VF induced by oxidative and ionic stress.
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Affiliation(s)
- Aneesh Bapat
- Translational Arrhythmia Research Section, University of California-Los Angeles Cardiovascular Research Laboratory, USA
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Bash LD, Buono JL, Davies GM, Martin A, Fahrbach K, Phatak H, Avetisyan R, Mwamburi M. Systematic Review and Meta-analysis of the Efficacy of Cardioversion by Vernakalant and Comparators in Patients with Atrial Fibrillation. Cardiovasc Drugs Ther 2012; 26:167-79. [DOI: 10.1007/s10557-012-6374-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Trigo P, Fischer GW. Managing atrial fibrillation in the elderly: critical appraisal of dronedarone. Clin Interv Aging 2012; 7:1-13. [PMID: 22291468 PMCID: PMC3267401 DOI: 10.2147/cia.s16677] [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] [Indexed: 12/01/2022] Open
Abstract
Atrial fibrillation is the most commonly seen arrhythmia in the geriatric population and is associated with increased cardiovascular morbidity and mortality. Treatment of the elderly with atrial fibrillation remains challenging for physicians, because this unique subpopulation is characterized by multiple comorbidities requiring chronic use of numerous medications, which can potentially lead to severe drug interactions. Furthermore, age-related changes in the cardiovascular system as well as other physiological changes result in altered drug pharmacokinetics. Dronedarone is a new drug recently approved for the treatment of arrhythmias, such as atrial fibrillation and/or atrial flutter. Dronedarone is a benzofuran amiodarone analog which lacks the iodine moiety and contains a methane sulfonyl group that decreases its lipophilicity. These differences in chemical structure are responsible for making dronedarone less toxic than amiodarone which, in turn, results in fewer side effects. Adverse events for dronedarone include gastrointestinal side effects and rash. No dosage adjustments are required for patients with renal impairment. However, the use of dronedarone is contraindicated in the presence of severe hepatic dysfunction.
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Affiliation(s)
- Paula Trigo
- Department of Anesthesiology, Mount Sinai School of Medicine, New York, NY, USA
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Curtis AB. Update on the clinical management of atrial fibrillation: guidelines and beyond. Postgrad Med 2012; 123:7-20. [PMID: 22104450 DOI: 10.3810/pgm.2011.11.2491] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In clinical practice, atrial fibrillation (AF) is the most commonly encountered arrhythmia. With the aging of the US population, the number of patients with AF that physicians encounter will increase. Atrial fibrillation management involves a combination of rate- and rhythm-control strategies with thromboprophylaxis, a complicated endeavor given side effect profiles of treatments, patient comorbidities, and anticoagulation treatment requirements. Early treatment discontinuation and poor compliance with anticoagulation treatment are frequent and result in increased mortality, a 5-fold increased risk of ischemic stroke, decreased health-related quality of life, and decreased exercise capacity. In 2006, the American College of Cardiology/American Heart Association/European Society of Cardiology (ACC/AHA/ESC) provided guidelines for the management of patients with AF. Recently, the ACC Foundation, AHA, and Heart Rhythm Society released updates to these guidelines (January and February 2011). This article aims to assist physicians in improving the management of patients with AF by focusing on the main components of therapy as reflected in the guidelines, and by providing an update on new US Food and Drug Administration-approved treatments.
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Manocha P, Bavikati V, Langberg J, Lloyd MS. Coronary artery disease potentiates response to dofetilide for rhythm control of atrial fibrillation. Pacing Clin Electrophysiol 2011; 35:170-3. [PMID: 22017595 DOI: 10.1111/j.1540-8159.2011.03245.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Dofetilide, a class III antiarrhythmic, is one of the few alternatives to amiodarone in patients with atrial fibrillation (AF) and heart failure or coronary artery disease (CAD). While amiodarone has been extensively studied, little is known about predictors of response to dofetilide. We sought to identify clinical parameters associated with dofetilide success in a large cohort of patients with AF. METHODS/RESULTS A total of 287 patients with AF started on dofetilide between 2001 and 2008 were included. Dofetilide was deemed "completely effective" if the patient remained on dofetilide at follow-up and had no recurrences of AF clinically or by electrocardiogram. Dofetilide efficacy was analyzed in relation to clinical variables relevant to AF and AF recurrence. After a follow-up of 10.2 ± 7.7 months, 54.7% of the patients remained on dofetilide and it was completely effective in 26.8%. The discontinuation rate during initial hospitalization was 13.3% from excessive QT prolongation and one patient with torsades de pointes (successfully treated). A history of CAD was the only univariate predictor of efficacy (odds ratio [OR] 2.27, 95% confidence interval [CI] 1.29-4.01, P < 0.05). CAD remained the only significant factor associated with efficacy of dofetilide in a multivariate regression model (OR 2.01, 95% CI 1.11-3.70, P < 0.05, n = 270). The overall efficacy of dofetilide in patients with CAD was 41.1%, compared to 23.5% in those without CAD (P < 0.05). CONCLUSIONS In this large cohort of patients with AF, underlying coronary disease was significantly associated with dofetilide success. This finding may have utility for clinical decisions regarding initiation of dofetilide.
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Affiliation(s)
- Pankaj Manocha
- Department of Cardiac Electrophysiology, Emory University Hospital, Atlanta, Georgia 30322, USA
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Conti A, Canuti E, Mariannini Y, Zanobetti M, Innocenti F, Paladini B, Pepe G, Padeletti L, Gensini GF. Aggressive approach and outcome in patients presenting atrial fibrillation and hypertension. Int J Cardiol 2011; 166:50-4. [PMID: 21985755 DOI: 10.1016/j.ijcard.2011.09.074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Accepted: 09/17/2011] [Indexed: 11/16/2022]
Abstract
AIM Aggressive approach in patients presenting atrial fibrillation (AF) and hypertension could result in improving rhythm control and reducing admission. METHODS Out of 3475 patients presenting AF, those with hypertension (n=1739, 52%) underwent standard (n=591, group 1, years 2004-2005) or aggressive pharmacological and electrical approach (n=1148, group 2, years 2006-2009). Overall, in 1071 patients AF duration was less than 48 h. Primary endpoint was rhythm conversion; secondary endpoints were modalities of rhythm conversion and reduction of admissions. RESULTS At univariate and multivariate analyses, AF lasting less than 48 h, absence of comorbidities and younger age were independent predictors of sinus rhythm; conversely, lack of sinus rhythm, older age, AF lasting more than 48 h and comorbidities were independent predictors of hospitalization. Overall, 55% of patients achieved sinus rhythm in group 1 versus 62% in group 2 (p=0.018). Interestingly, in patients with AF lasting less than 48 h, 89% achieved sinus rhythm, more likely by class 1C than by class III antiarrhythmic drugs (p<0.001). Overall reduction of admission accounts for 60%; 50% of patients need admission in group 1 versus 29% in group 2 (p<0.001). CONCLUSIONS Aggressive pharmacological and electrical approach in patients presenting AF and hypertension significantly improved rhythm conversion overall up to 62%. Patients with AF lasting less than 48 h eventually achieved sinus rhythm up to 89%, mostly by class IC antiarrhythmic drugs. Admissions eventually reduced up to 60%.
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Affiliation(s)
- Alberto Conti
- Emergency Medicine, Department of Medical and Surgical Critical Care, University of Florence and Careggi University Hospital, Florence, Italy.
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Saliba W, Wazni OM. Sinus rhythm restoration and treatment success: insight from recent clinical trials. Clin Cardiol 2011; 34:12-22. [PMID: 21259273 DOI: 10.1002/clc.20826] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Atrial fibrillation (AF) is a common supraventricular tachyarrhythmia with substantial morbidity and mortality. This review briefly describes the mechanisms of AF development and progression, including electrical, structural, and contractile remodeling. In addition, the potential benefits of achieving and maintaining sinus rhythm are discussed. For example, rhythm control has been associated with improvements in left ventricular function, AF symptoms, exercise tolerance, the ability to perform activities of daily living, and quality of life. More recently, dronedarone, a noniodinated benzofuran derivative approved for use in the treatment of AF, was shown to significantly improve clinical outcomes including cardiovascular hospitalizations and death from any cause in A Placebo-Controlled, Double-Blind, Parallel Arm Trial to Assess the Efficacy of Dronedarone 400 mg bid for the Prevention of Cardiovascular Hospitalization or Death From Any Cause in Patients With Atrial Fibrillation/Atrial Flutter (ATHENA). The review concludes with an examination of AF treatment options and expectations. Evidence suggests that the complete absence of AF recurrence is not always achievable; however, complete restoration of sinus rhythm may not be necessary for patients to achieve clinically meaningful benefits. Copyright © 2011 Wiley Periodicals, Inc. The editorial assistance provided for this manuscript was funded by Sanofi-Aventis. The authors were fully responsible for all content and editorial decision, and received no financial support or other form of compensation related to the development of the paper. The authors have no other funding, financial relationships, or conflicts of interest to disclose.
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Affiliation(s)
- Walid Saliba
- Department of Cardiovascular Medicine, Cleveland Clinic Foundation, Cleveland, Ohio, USA.
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Rhythm control strategies and the role of antiarrhythmic drugs in the management of atrial fibrillation: focus on clinical outcomes. J Gen Intern Med 2011; 26:531-7. [PMID: 21108047 PMCID: PMC3077493 DOI: 10.1007/s11606-010-1574-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2010] [Revised: 09/13/2010] [Accepted: 10/20/2010] [Indexed: 10/18/2022]
Abstract
Atrial fibrillation (AF) is a common disorder that significantly impacts the lives of affected patients. The restoration of sinus rhythm may prevent AF progression and reduce the occurrence of negative sequelae; however, available antiarrhythmic drugs (AADs) have largely failed to demonstrate significant benefit relative to rate control with respect to morbidity and mortality outcomes. The review commentary will address current knowledge regarding the pathologic mechanisms of AF, current trials that investigate rate and rhythm strategies, and future therapies that may change treatment approaches based on preliminary evidence suggesting a more favorable safety profile. The observed outcomes are likely a reflection of the limited efficacy plus poor safety and tolerability of available AADS. However, data from patients who attained and maintained sinus rhythm in a number of clinical studies demonstrate that the achievement of normal sinus rhythm can indeed reduce AF-associated morbidity and mortality. Furthermore, the results of trials designed to assess specific morbidity and mortality outcomes such as cardiovascular death hospitalization suggest that the development of safer AF therapies, whether pharmacologic or nonpharmacologic, can potentially improve clinical outcomes.
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Fuster V, Rydén LE, Cannom DS, Crijns HJ, Curtis AB, Ellenbogen KA, Halperin JL, Kay GN, Le Huezey JY, Lowe JE, Olsson SB, Prystowsky EN, Tamargo JL, Wann LS. 2011 ACCF/AHA/HRS Focused Updates Incorporated Into the ACC/AHA/ESC 2006 Guidelines for the Management of Patients With Atrial Fibrillation. Circulation 2011; 123:e269-367. [PMID: 21382897 DOI: 10.1161/cir.0b013e318214876d] [Citation(s) in RCA: 592] [Impact Index Per Article: 45.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Bunch TJ, Crandall BG, Weiss JP, May HT, Bair TL, Osborn JS, Anderson JL, Muhlestein JB, Horne BD, Lappe DL, Day JD. Patients Treated with Catheter Ablation for Atrial Fibrillation Have Long-Term Rates of Death, Stroke, and Dementia Similar to Patients Without Atrial Fibrillation. J Cardiovasc Electrophysiol 2011; 22:839-45. [PMID: 21410581 DOI: 10.1111/j.1540-8167.2011.02035.x] [Citation(s) in RCA: 293] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- T Jared Bunch
- Intermountain Heart Rhythm Specialists Department of Cardiology, Intermountain Medical Center, Murray, Utah 84107, USA.
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48
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Fuster V, Rydén LE, Cannom DS, Crijns HJ, Curtis AB, Ellenbogen KA, Halperin JL, Kay GN, Le Huezey JY, Lowe JE, Olsson SB, Prystowsky EN, Tamargo JL, Wann LS. 2011 ACCF/AHA/HRS Focused Updates Incorporated Into the ACC/AHA/ESC 2006 Guidelines for the Management of Patients With Atrial Fibrillation. J Am Coll Cardiol 2011; 57:e101-98. [PMID: 21392637 DOI: 10.1016/j.jacc.2010.09.013] [Citation(s) in RCA: 543] [Impact Index Per Article: 41.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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49
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Abstract
Dronedarone, an amiodarone analog, was developed to be a safer alternative to amiodarone. Dronedarone is useful in suppressing atrial fibrillation/flutter and controlling the ventricular response. Dronedarone reduced cardiovascular hospitalization in the ATHENA trial (A placebo-controlled, double-blind, parallel arm Trial to assess the efficacy of dronedarone 400 mg bid for the prevention of cardiovascular Hospitalization or death from any cause in patiENts with Atrial fibrillation/atrial flutter). This paper reviews the results of ATHENA, including subsequent sub-analyses of the trial. These results raise the hypothesis that many of the benefits noted from this trial may be secondary to more than the antiarrhythmic properties of dronedarone. Future studies will clarify the mechanisms of this beneficial effect.
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Affiliation(s)
- Gerald V Naccarelli
- Heart and Vascular Institute, Penn State University College of Medicine, Hershey, PA, USA.
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50
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Qu Z. Chaos in the genesis and maintenance of cardiac arrhythmias. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2010; 105:247-57. [PMID: 21078337 DOI: 10.1016/j.pbiomolbio.2010.11.001] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Revised: 07/04/2010] [Accepted: 11/05/2010] [Indexed: 11/18/2022]
Abstract
Dynamical chaos, an irregular behavior of deterministic systems, has been widely shown in nature. It also has been demonstrated in cardiac myocytes in many studies, including rapid pacing-induced irregular beat-to-beat action potential alterations and slow pacing-induced irregular early afterdepolarizations, etc. Here we review the roles of chaos in the genesis of cardiac arrhythmias, the transition to ventricular fibrillation, and the spontaneous termination of fibrillation, based on evidence from computer simulation of mathematical models and experiments of animal models.
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Affiliation(s)
- Zhilin Qu
- Department of Medicine (Cardiology), David Geffen School of Medicine at University of California, 650 Charles E. Young Drive South, Los Angeles, CA 90095, USA.
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