Dronedarone or amiodarone for rhythm control for atrial fibrillation: implications from the DIONYSOS study

Management of persistent AF involves rhythm or rate control strategies and thromboprophylaxis for cardioembolic events. Although amiodarone appears to be more effective than other current antiarrhythmics for a rhythm control approach in AF patients, many side effects limit its long-term use. Dronedarone is a new antiarrhythmic drug that may offer advantages for rhythm control, given its relative safety (although not in patients with decompensated heart failure), efficacy and tolerability. With regard to the latter, dronedarone has fewer adverse effects and is better tolerated than amiodarone. Nonetheless, in one head-to-head comparison of dronedarone and amiodarone, the latter drug was superior to dronedarone for maintenance of sinus rhythm post cardioversion, but dronedarone was safer and better tolerated, with useful benefit to decrease hospitalizations and thus healthcare costs. This provides clinicians (and patients) with a new option when choosing antiarrhythmic therapy.     

Dronedarone or amiodarone for rhythm control for atrial fibrillation: implications from the DIONYSOS study

Management of persistent AF involves rhythm or rate control strategies and thromboprophylaxis for cardioembolic events. Although amiodarone appears to be more effective than other current antiarrhythmics for a rhythm control approach in AF patients, many side effects limit its long-term use. Dronedarone is a new antiarrhythmic drug that may offer advantages for rhythm control, given its relative safety (although not in patients with decompensated heart failure), efficacy and tolerability. With regard to the latter, dronedarone has fewer adverse effects and is better tolerated than amiodarone. Nonetheless, in one head-to-head comparison of dronedarone and amiodarone, the latter drug was superior to dronedarone for maintenance of sinus rhythm post cardioversion, but dronedarone was safer and better tolerated, with useful benefit to decrease hospitalizations and thus healthcare costs. This provides clinicians (and patients) with a new option when choosing antiarrhythmic therapy.     

Atrial Ca2+ signaling in atrial fibrillation as an antiarrhythmic drug target

Atrial fibrillation (AF) is the most frequent arrhythmia and is associated with increased morbidity and mortality. Current drugs for AF treatment have moderate efficacy and increase the risk of life-threatening antiarrhythmias, making novel drug development crucial. Newer antiarrhythmic drugs like dronedarone and possibly vernakalant are efficient and may have less proarrhythmic potential. Emerging evidence suggests that abnormal intracellular Ca²⁺ signaling is the key contributor to focal firing, substrate evolution, and atrial remodeling during AF. Accordingly, identification of the underlying atrial Ca²⁺-handling abnormalities is expected to discover novel mechanistically based therapeutic targets. This article reviews the molecular mechanisms of altered Ca²⁺ signaling in AF and discusses the potential value of novel approaches targeting atrial Ca²⁺-handling abnormalities.     

Will warfarin soon be passé? New approaches to stroke prevention in atrial fibrillation

Atrial fibrillation (AF) is the most common cause for thromboembolic stroke. Oral anticoagulation with warfarin is still the most effective therapy in patients with AF, who are at an increased risk for stroke. Nevertheless, warfarin therapy has several limitations; therefore, new anticoagulants like warfarin analogs, thrombin inhibitors, or factor Xa inhibitors have been developed. Some of them are currently being tested in phase III trials in patients with AF. Furthermore, the pathophysiology of prothrombotic endocardial remodeling in fibrillating atria suggests that angiotensin II increases prothrombotic expression of vascular adhesion molecules at the atrial endocardium. Thus, novel anticoagulants or hybrid therapy with a combination of anticoagulants with inhibitors of endocardial remodelling like angiotensin II receptor blockers appear to be attractive future perspective approaches.     

Antiarrhythmic drugs for atrial fibrillation

INTRODUCTION: Atrial fibrillation (AF) is associated with increased mortality and morbidity. Although stroke prevention is the only way to improve prognosis, antiarrhythmic drugs (AADs) are of primary importance both in the conversion to sinus rhythm and in the long-term control of rhythm and rate. AREAS COVERED: We searched the Cochrane Library and Medline Database for articles published in English concerning efficacy and safety of AADs in AF. Particular attention was paid to the recently published European Society of Cardiology guidelines. This review provides an overview of the currently available drugs used in AF, with a particular emphasis on their comparative efficacy and safety in different kind of patients. Recent important findings, and advantages and disadvantages of recently approved drugs such as vernakalant and dronedarone, are also discussed. EXPERT OPINION: AADs remain fundamental in the acute and long-term management of AF, to control symptoms and to reduce the negative impact of the arrhythmia on QoL. The choice of a rate- over rhythm-control strategy should be individualized and based on accurate evaluation of patient medical history and symptoms. New agents will contribute to improve treatment efficacy together with the guarantee of better safety profiles.     

Challenges and Treatment for Stroke Prophylaxis in Patients with Atrial Fibrillation in Mexico: A Review

Atrial fibrillation (AF) is associated with an increased risk of stroke. AF-related strokes cause greater disability and mortality than those in patients without AF, and are associated with a significant clinical and economic burden in Mexico. Antithrombotic therapy reduces stroke risk in patients with AF and is recommended for all patients except those classified as having a low stroke risk. However, its use is suboptimal all around the world; one study showed that only 4 % of Mexican patients with AF who presented with ischemic stroke were in the therapeutic range for anticoagulation. Vitamin K antagonists (VKAs) such as warfarin or acenocoumarin have long been the only oral anticoagulants for stroke prevention in AF. Although effective, VKAs have disadvantages, including the need for regular coagulation monitoring and dose adjustment. Interactions with numerous common medications and foods contribute to the risk of serious bleeding and thrombotic events in VKA-treated patients. Thus novel oral anticoagulants (NOACs), more properly called direct oral anticoagulants (DOACs), such as dabigatran etexilate, rivaroxaban, apixaban, and edoxaban (not available in Mexico), have been developed. These offer the convenience of fixed-dose treatment without the need for monitoring, and have few drug or food interactions. Pivotal phase III trials have demonstrated that these agents are at least as effective as warfarin in preventing stroke and are associated with a reduced risk of intracranial hemorrhage. With apixaban approved in Mexico in April 2013, clinicians now have the choice of three novel DOACs as alternatives to warfarin. However, it is yet to be established which of these agents should be the first choice, and treatment decisions are likely to depend on the individual patient’s characteristics.     

Oral IIa and Xa inhibitors for prevention of stroke in atrial fibrillation: clinical studies and regulatory considerations

Atrial fibrillation (AF), the most common, clinically significant, cardiac arrhythmia affects 1% of the general population and has important hemodynamic and thromboembolic complications that contribute to elevated morbidity and mortality. AF increases the overall risk of stroke five-fold, accounting for approximately 15% of all strokes and is associated with particularly severe stroke. For the last 50 years, long-term anticoagulation with vitamin K antagonists has been the most effective therapy for preventing stroke and systemic embolism in patients with AF and other risk factors, but their use has a lot of limitations and drawbacks (frequent monitoring and dose adjustment, food and drug interactions, delayed onset of action etc). Nowadays, new oral anticoagulants have emerged that seem to overcome those limitations. Direct thrombin inhibitor dabigatran and factor Xa inhibitors rivaroxaban and apixaban have proven, in large, multicenter, randomized, phase III, clinical studies, to be at least as efficient as warfarin in stroke prevention in patients with AF. RELY and ROCKET AF trials have contributed to market approval of dabigatran and rivaroxaban, respectively and made them available to clinical practice. Another factor Xa inhibitor, edoxaban, is under evaluation in an ongoing phase III clinical trial and others such as AZD0837, betrixaban and darexaban are still in safety and tolerability phase II studies. The oral anticoagulation landscape is changing rapidly and these new agents seem to be very promising. However future post-marketing studies and registries will help clarify their efficacy and safety.     

Non-Antiarrhythmic Drugs to Prevent Atrial Fibrillation

Atrial fibrillation (AF) is the most frequent arrhythmia found in clinical practice. The majority of patients with AF are still candidates for antiarrhythmic drug treatment, not only for acute reversion to sinus rhythm but also for long-term treatment to prevent recurrences of AF. Currently available antiarrhythmic drugs, however, are unable to provide complete efficacy in all patients, and present problematic risks of proarrhythmia. The progressively increasing prevalence of AF supports the need to develop improved therapeutic approaches for the clinical management of arrhythmia. Accordingly, new treatment techniques aimed at suppressing the origin of the arrhythmogenic foci have been developed in the last decade. However, ablative treatments are only available for selected patients. Because of these factors, and also because primary prevention of AF should be our goal, the introduction of non-antiarrhythmic agents that could prevent both new-onset AF and recurrences of AF may eventually improve patient outcomes and reduce the incidence of this epidemic disease. The potential clinical value of these non-antiarrhythmic options is currently under active investigation. There is now clinical and experimental evidence that many drugs may have beneficial effects in preventing AF through several possible mechanisms. Non-antiarrhythmic drugs, such as ACE inhibitors and angiotensin receptor blockers, HMG-CoA reductase inhibitors (statins), corticosteroids, and N-3 polyunsaturated fatty acids may have a positive effect in patients with AF or in preventing AF in patients at risk.     

Pharmacological approaches in the treatment of atrial fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and is associated with substantial cardiovascular morbidity and mortality. The arrhythmia can be initiated and/or maintained by rapidly firing foci, single- and multiple-circuit reentry. Once initiated, AF alters atrial electrical and structural properties (atrial remodeling) in a way that promotes its own maintenance and recurrence and may alter the response to antiarrhythmic drugs. Thus, initial episodes of paroxysmal (self-terminating) AF lengthens to the point where the arrhythmia becomes persistent (requires cardioversion to restore sinus rhythm) and permanent. AF usually requires a trigger for initiation and a favorable electrophysiological and/or anatomical substrate for maintenance. The substrate includes both cardiovascular (coronary artery disease, valvular heart disease, heart failure, hypertension, dilated cardiomyopathy) and non cardiovascular diseases (thyrotoxicosis, pulmonary diseases). Accordingly, the initial step in patients with AF requires a careful assessment of symptoms and identification of underlying reversible triggers and potentially modifiable underlying structural substrate and treat them aggressively. In contrast to other cardiac arrhythmias, antiarrhythmic drugs (ADs) are the mainstay of therapy. Long-term treatment of AF is directed to restore and maintain the sinus rhythm with class I and III ADs (rhythm-control) or to allow AF to persist and ensure that the ventricular rate is controlled (rate-control) with atrioventricular nodal blocking drugs (digoxin, beta-blockers, verapamil, diltiazem) and prevent thromboembolic complications with anticoagulants. However, the long-term efficacy of ADs for preventing AF recurrence is far from ideal, because of limited efficacy (AF recurs in at least one-half of the patients) and potential side effects, particularly proarrhythmia. Thus, the choice of the appropriate AD will depend on the temporal pattern of the arrhythmia, the presence of associated diseases, easy of administration and adverse effects profile, particularly the risk of proarrhythmia. The recent finding that angiotensin converting enzyme inhibitors and beta-blockers reduce the incidence of AF in patients post myocardial infarction with left ventricular dysfunction confirmed the importance of targeting the underlying arrhythmogenic substrate. This review focuses on the mechanisms underlying AF and the mechanism of action and the efficacy and safety profile of the ADs used in the treatment of atrial fibrillation. The advantages and disadvantages of rhythm and rate control, the role pill in a pocket concept and the role of the new ADs are dicussed.     

Dronedarone as a new treatment option for atrial fibrillation patients: pharmacokinetics,pharmacodynamics and clinical practice

Importance of the field: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, affecting 1 – 2% of the population. Despite several developments in antithrombotic, antiatherosclerotic and device-based cardiac therapies, few noteworthy antiarrhythmic drugs have been developed.

Areas covered in this review: Dronedarone, a modified analogue of amiodarone, has the pharmacological ability of blocking multiple ion channels. This overview summarizes the pharmacokinetic and pharmacodynamic properties of dronedarone, evaluates its potential application to daily clinical cardiology practice according to the evidence provided by clinical trials, and provides a future clinical perspective for the use of this drug.

What the reader will gain: The readers will gain an understanding of the findings of recent trials performed with dronedarone, which will provide important information for this relatively new antiarrhythmic drug, used for the treatment of atrial fibrillation.

Take home message: Dronedarone provides a reasonable efficacy and safety profile. Recent clinical trials indicate that dronedarone may support maintenance of sinus rhythm, decrease hospitalizations and reduce healthcare costs even in AF patients with structural heart disease but without severe or unstable cardiac failure.     

Dronedarone. atrial fibrillation: too many questions about long-term adverse effects

In patients with atrial fibrillation, a betablocker is generally used initially to prevent recurrence or to slow the heart rate. Amiodarone is a last resort, mainly because of its numerous adverse effects. Dronedarone, chemically similar to amiodarone,was recently authorised for this indication in the European Union. In a double-blind trial versus amiodarone in 504 patients, the failure rate was significantly higher with dronedarone (75.1% versus 58.8%). Two placebo-controlled trials in heart failure patients yielded conflicting results. Dronedarone was associated with a statistically significant increase in mortality in a trial in 627 symptomatic patients free of arrhythmias. However, there was no statistically significant difference in a trial including 4630 patients with atrial fibrillation and a lower risk of cardiovascular events. There are no comparative trials versus other antiarrhythmic drugs or heart-rate-lowering agents, including betablockers and calcium channel blockers. Like other antiarrhythmic drugs, dronedarone also has arrhythmogenic effects, including bradycardia and QT prolongation. Other adverse effects include diarrhoea, nausea and vomiting, and cutaneous disorders. Transient elevation of creatinine levels is also frequent, and cases of renal failure have been reported. In the trial versus amiodarone, dronedarone had a different pattern of short-term adverse effects, including more gastrointestinal disorders but less frequent thyroid disorders, neurological disorders, hypersensitivity reactions, hypertension, and QT prolongation. Little is known of potential long-term adverse effects, especially pulmonary fibrosis. In practice, dronedarone is better tolerated but less effective than amiodarone in the short term.When antiarrhythmic drug therapy is needed, it is better to continue to use a betablocker or, as a last resort, amiodarone, a drug with better-documented adverse effects, especially during long-term treatment.     

Antiarrhythmic drugs for atrial fibrillation

Introduction: Atrial fibrillation (AF) is associated with increased mortality and morbidity. Although stroke prevention is the only way to improve prognosis, antiarrhythmic drugs (AADs) are of primary importance both in the conversion to sinus rhythm and in the long-term control of rhythm and rate.

Areas covered: We searched the Cochrane Library and Medline Database for articles published in English concerning efficacy and safety of AADs in AF. Particular attention was paid to the recently published European Society of Cardiology guidelines. This review provides an overview of the currently available drugs used in AF, with a particular emphasis on their comparative efficacy and safety in different kind of patients. Recent important findings, and advantages and disadvantages of recently approved drugs such as vernakalant and dronedarone, are also discussed.

Expert opinion: AADs remain fundamental in the acute and long-term management of AF, to control symptoms and to reduce the negative impact of the arrhythmia on QoL. The choice of a rate- over rhythm-control strategy should be individualized and based on accurate evaluation of patient medical history and symptoms. New agents will contribute to improve treatment efficacy together with the guarantee of better safety profiles.     

Dronedarone and the Incidence of Stroke in Patients with Paroxysmal or Persistent Atrial Fibrillation

Background

Stroke is the most feared complication of atrial fibrillation (AF). Dronedarone is an antiarrhythmic drug with multichannel-blocking properties. Recently, a post hoc analysis of a large randomized trial has suggested a reduction of stroke risk in patients with paroxysmal or persistent AF receiving dronedarone.

Objective

We performed a systematic review and meta-analysis on the effect of dronedarone on the occurrence of stroke or transient ischemic attack (TIA) in patients with paroxysmal or persistent AF.

Methods

We searched PubMed, EMBASE, and ISI Web of Knowledge as well as abstracts of major conferences for randomized trials comparing dronedarone with placebo in patients with paroxysmal or persistent AF. The endpoint was the occurrence of stroke or TIA during follow-up. Fixed effect risk differences (RDs) were calculated with the Mantel-Haenszel method. We also performed random effects analysis with the DerSimonian Laird method.

Results

Four trials were included in the analysis; a total of 5967 patients were analyzed, 3183 receiving dronedarone 400 mg twice daily and 2784 receiving placebo. 160 strokes or TIAs were reported in the four trials: 67 in the dronedarone group (2.1%) and 93 in the placebo group (3.3%). In the fixed effect model, patients in the dronedarone group had a significantly lower risk for the occurrence of stroke or TIA during follow-up compared with patients in the placebo group. The RD of the incidence of stroke or TIA in all trials between patients randomized to dronedarone and those randomized to placebo was ?0.0094 (95% confidence interval [CI] ?0.0178, ?0.0011; p = 0.027). The ATHENA trial had by far the highest statistical weight (79.5%). There was no evidence of heterogeneity (χ² = 2.41, p = 0.300). In the random effects model, the statistical weight of the ATHENA trial was much lower (45.1%) and the RD for stroke or TIA between the dronedarone and the placebo groups did not reach statistical significance (RD ?0.0064, 95% CI ?0.0144, 0.0016; p = 0.120).

Limitations

First, stroke was not a prespecified outcome measure in the included trials. Second, we did not analyze trials studying patients with permanent AF; very recent data show an adverse outcome in patients with permanent AF receiving dronedarone.

Conclusions

The meta-analysis indicates a reduced risk of stroke or TIA in patients with paroxysmal or persistent AF receiving dronedarone. These findings are largely due to the results of the ATHENA trial. Further research on this topic is necessary.     

Evaluation and management of atrial fibrillation

Atrial fibrillation (AF) is the most common clinically encountered arrhythmia affecting 0.4% of the general population. Its prevalence increases with age, affecting more than 6% of people over 80 years of age. The annual risk of ischemic stroke in patients with lone AF is approximately 1.3%. This annual risk increases up to 10% -12% in patients with a prior stroke or transient ischemic attack. Randomized clinical trials (RCT) comparing adjusted-dose oral anticoagulation and placebo showed a risk reduction of 61% (95% CI 47% to 71%). The absolute risk reduction for stroke with oral anticoagulants is about 3% per year. Aspirin has been shown in meta-analyses to have on average a 20-25% relative risk reduction, and is inferior to oral anticoagulants. In high risk patients with AF warfarin is a class I ACC/AHA indication unless there is a contraindication for anticoagulation. Unfortunately, this therapy requires frequent monitoring with blood samples and the interaction with food and several medications makes its use difficult and sometimes unreliable. It requires strict patient compliance and its use is also linked to potentially serious bleeding complications. In clinical practice, less than 60% of patients who do not have contraindications to oral anticoagulation are actually receiving them. Additionally, of those that receive oral anticoagulation, less than 50% are consistently within therapeutic targets. As such, the "real world" efficacy of a strategy towards prescribing oral anticoagulants is likely significantly lower than that demonstrated in clinical trials. As such, the need to discover other methods of anticoagulation with oral bioavailability, predictable pharmacokinetics, and minimal interactions with diet and other pharmacological agents is imperative. Low molecular weight heparin has a more predictable bioavailability and a longer half-life, but its subcutaneous mode of administration and long-term risks, in particular, osteoporosis makes the chronic use of this medication non-feasible. Antiplatelet agents such as clopidogrel have proven efficacy and superiority compared to aspirin to prevent systemic vascular events in at-risk patient populations, but currently they do not play an important role in the prevention of AF related thromboembolic events. The ACTIVE study is a randomized trial comparing the combination of clopidogrel and aspirin therapy to oral anticoagulation with warfarin in patients with AF, and was unfortunately terminated prematurely by the data safety and monitoring board because of increased events in the antiplatelet arm. Direct thrombin inhibitors, such as ximelagatran, may be as effective as warfarin for stroke-risk reduction in patients with AF. No anticoagulation monitoring is needed and it has excellent bioavailability, with a twice-daily oral dose. Elevation of liver enzymes was an initial concern regarding the use of this new drug, which is not available for general use. Ongoing pharmacological research and future clinical trials may one day leave the "warfarin days" behind. Unfortunately, the new therapies that are being tested seem to be at least several years away from being available on a widespread basis. In this review, we discuss the underlying pathophysiology of AF and stroke. We also provide a comprehensive discussion regarding various available therapies to treat AF.     

Pharmacologic targets for atrial fibrillation

Despite advances in treatment, atrial fibrillation (AF) remains the most common arrhythmia in humans. Antiarrhythmic drug therapy continues to be a cornerstone of AF treatment, even in light of emerging non-pharmacologic therapies. Conventional antiarrhythmic drugs target cardiac ion channels and are often associated with modest AF suppression and the risk of ventricular proarrhythmia. Ongoing drug development has focused on targeting atrial-specific ion channels as well as novel non-ionic targets. Targeting non-ionic mechanisms may also provide new drugs directed towards the underlying mechanisms responsible for AF and possibly greater antiarrhythmic potency. Agents that act against these new targets may offer improved safety and efficacy in AF treatment.     

Pharmacologic targets for atrial fibrillation

Despite advances in treatment, atrial fibrillation (AF) remains the most common arrhythmia in humans. Antiarrhythmic drug therapy continues to be a cornerstone of AF treatment, even in light of emerging non-pharmacologic therapies. Conventional antiarrhythmic drugs target cardiac ion channels and are often associated with modest AF suppression and the risk of ventricular proarrhythmia. Ongoing drug development has focused on targeting atrial-specific ion channels as well as novel non-ionic targets. Targeting non-ionic mechanisms may also provide new drugs directed towards the underlying mechanisms responsible for AF and possibly greater antiarrhythmic potency. Agents that act against these new targets may offer improved safety and efficacy in AF treatment.     

New and emerging anticoagulant therapy for atrial fibrillation and acute coronary syndrome

Abstract Thrombosis is an underlying cause of many cardiovascular disorders, and generation of thrombi in the arterial circulation can lead to unstable angina, myocardial infarction, or ischemic stroke. Antithrombotic therapy is widely used, with proven benefit to prevent ischemic stroke and thromboembolic events in patients with atrial fibrillation (AF) or to prevent further ischemic complications in patients with acute coronary syndrome (ACS). Traditional anticoagulants (including unfractionated heparin, low-molecular-weight heparin, and warfarin) and antiplatelet agents (including aspirin, clopidogrel, and prasugrel) are typically used for these indications. Limitations to their use include variable pharmacokinetic and pharmacodynamic profiles, inability to inhibit fibrin-bound thrombin, risk of heparin-induced thrombocytopenia, delayed onset of action, numerous drug interactions, need for substantial laboratory monitoring and dosage titrations, hyporesponsiveness or resistance, hypersensitivity, adverse events, and bleeding. To overcome some of the limitations of traditional agents, new antithrombotic agents under development are highly selective for specific coagulation factors blocking the synthesis of thrombin. Clinicians must have an understanding of the new anticoagulants to aid in the selection of appropriate therapies for patients. We describe the most relevant phases II and III clinical trials that evaluated several recent emerging anticoagulant drugs for use in patients with AF or ACS. The advantages of many new agents include predictable pharmaco-dynamic response and pharmacokinetic parameters, allowing for fixed oral dosing with no need for laboratory monitoring. For patients with AF, dabigatran is already approved for the prevention of stroke and systemic embolism, rivaroxaban appears to be an effective alternative to warfarin in high-risk patients, and apixaban may also be an effective alternative to aspirin in patients unable to take warfarin. Otamixaban shows promise as an intravenous alternative for patients with ACS in the acute care setting. Likewise, rivaroxaban, dabigatran, and darexaban with or without dual antiplatelet therapy may be beneficial for secondary prevention of ischemic events in patients with ACS.     

新型口服抗凝药物用于房颤患者抗凝治疗的研究进展

房颤是临床常见且严重的心律失常之一,脑卒中是房颤最常见和危险的并发症,口服抗凝药物是防治并发症的关键手段。新型口服抗凝药的研发克服了华法林治疗窗窄、需要长期监测INR的弊端,但也有许多临床试验在证明新型口服抗凝药疗效的同时,验证和发现了出血、肝损伤等不良反应。现将新型口服抗凝药物用于房颤患者抗凝治疗的研究进展做一综述。     

Dofetilide: a new drug to control cardiac arrhythmia

Atrial fibrillation (AF) is the most common cardiac arrhythmia. Mortality, and especially morbidity caused by AF, are major and growing health problems in the western world. AF is strongly associated with arterial hypertension, congestive heart failure, valvular heart disease, ischaemic heart disease, and with prevalence increasing with age. A variety of drugs have been used to terminate or prevent AF but, as many antiarrhythmic agents have the potential life-threatening pro-arrhythmia, safety problems remain. Dofetilide (Tikosyn, Pfizer), a new Vaughan Williams class III antiarrhythmic agent, has been developed and approved for the treatment of AF. In contrast to most antiarrhythmic agents, the development programme included two safety studies in high-risk patients. Dofetilide is effective and safe when an elaborate procedure for dosing is implemented. Along with amiodarone and betablockers, dofetilide is the only antiarrhythmic drug, which is recommended by guidelines for the treatment of AF in a wide range of patients.     

心房颤动抗栓药物治疗进展

心房颤动(房颤)是导致卒中和外周栓塞的重要独立预测因素,华法林抗凝治疗可降低卒中率,但目前华法林临床应用不足。正在研究或已经上市的新型抗栓药物包括达比加群酯、利伐沙班和阿派沙班等可能革命性的改变这一现状。