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Meta-analysis of dabigatran vs warfarin in patients undergoing catheter ablation for atrial fibrillation

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... However since warfarin still requires significant monitoring and long duration of onset, new oral anticoagulants (NOACs) have been introduced as alternatives (71). These NOACs, such as dabigatran and rivaroxaban act via direct inhibition of factor Xa or thrombin and have less drug interactions than warfarin (29,71,72). Studies have also demonstrated similar efficacy profiles for rivaroxaban, dabigatran and warfarin in patients undergoing catheter ablation (29,72). ...
... These NOACs, such as dabigatran and rivaroxaban act via direct inhibition of factor Xa or thrombin and have less drug interactions than warfarin (29,71,72). Studies have also demonstrated similar efficacy profiles for rivaroxaban, dabigatran and warfarin in patients undergoing catheter ablation (29,72). Ultimately, assessing the risk of stroke is essential for determining the treatment that will be most effective in improving outcomes and quality of life of patients with AF. ...
Article
Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia in modern clinical practice, with an estimated prevalence of 1.5–2%. The prevalence of AF is expected to double in the next decades, progressing with age and increasingly becoming a global medical challenge. The first-line treatment for AF is often medical treatment with either rate control or anti-arrhythmic agents for rhythm control, in addition to anti-coagulants such as warfarin for stroke prevention in patient at risk. Catheter ablation has emerged as an alternative for AF treatment, which involves myocardial tissue lesions to disrupt the underlying triggers and substrates for AF. Surgical approaches have also been developed for treatment of AF, particularly for patients requiring concomitant cardiac surgery or those refractory to medical and catheter ablation treatments. Since the introduction of the Cox-Maze III, this procedure has evolved into several modern variations, including the use of alternative energy sources (Cox-Maze IV) such as radiofrequency, cryo-energy and microwave, as well as minimally invasive thoracoscopic epicardial approaches. Another recently introduced technique is the hybrid ablation approach, where in a single setting both epicardial thoracoscopic ablation lesions and endocardial catheter ablation lesions are performed by the cardiothoracic surgeon and cardiologist. There remains controversy surrounding the optimal approach for AF ablation, energy sources, and lesion sets employed. The goal of this article is review the history, classifications, pathophysiology and current treatment options for AF.
... In line with uninterrupted warfarin, uninterrupted dabigatran and subsequently rivaroxaban have been compared with uninterrupted warfarin, each demonstrating comparable risk of embolic events with possibly decreased bleeding complications. [16][17][18][19][20][21][22][23][24][25][26] In a 2013 study involving 999 consecutive patients undergoing AF ablation, researchers compared those on uninterrupted warfarin to those on dabigatran 150 mg twice a day (with one to two doses withheld preablation), who were propensity matched to controls, and found no difference in thromboembolic or bleeding complications. 16 Similarly, in meta-analyses comparing the use of dabigatran to uninterrupted warfarin, similar rates of thromboembolic and bleeding were observed in the majority of cases. ...
... 16 Similarly, in meta-analyses comparing the use of dabigatran to uninterrupted warfarin, similar rates of thromboembolic and bleeding were observed in the majority of cases. [18][19][20] In 2014, a large, retrospective single-center analysis involving 1,745 patients with different preablation anticoagulation regimens showed overall very low major bleeding rates or thromboembolic rates when comparing the use of warfarin plus low-molecular-weight heparin bridging with aspirin, dabigatran with no bridging, and rivaroxaban with no bridging pre-AF ablation. All patients underwent preprocedural TEE. ...
Article
In the past decade, certain patient groups have been observed to have a presumptive lower incidence of left atrial (LA)/LA appendage (LAA) thrombus, particularly those who have no or minimal comorbidities. This has led to the question of whether a preprocedural evaluation of the LA/LAA is necessary in every patient, or if it can be avoided in certain patient populations. The answer to this is further complicated by the possibility of newer anticoagulation approaches affecting the incidence of intracardiac thrombus, including uninterrupted warfarin therapy and uninterrupted novel oral anticoagulant (NOAC) therapy, both of which are becoming more common. In this study, we conducted a comprehensive review of the literature addressing these questions in an attempt to summarize current approaches to evaluating the LA/LAA prior to ablation in order to elucidate the strategies that are currently being employed, to determine which strategies are becoming more favorable for use, and to identify what topics can or should be targeted for future study. In addition, this paper seeks to address the following specific questions: is ruling out LA/LAA thrombus necessary in all patients prior to atrial fibrillation (AF) ablation? Are there any identifiable patient populations at reliably lower risk who could potentially avoid LA/LAA thrombus screening prior to AF ablation? What are the current strategies being employed by electrophysiologists in the published literature? What is the opinion of the current literature on warfarin and NOAC drugs as they pertain to the incidence of LA/LAA thrombus prior to AF ablation, and how does each fit into the current treatment strategies for the prevention of procedural thromboembolism? Finally, what is the future of preprocedural intracardiac thrombus evaluation prior to AF ablation, and what steps can be taken to ensure that the risk to the patient is minimized while improving laboratory efficiency and avoiding unnecessary costs?
... However, routine laboratory monitoring on international normalized ratio (INR) and inevitable dose adjustments, potential interactions with several drugs and food, presented significant inconvenience and challenge in managing patients taking warfarin on daily medical practice [1]. Dabigatran etexilate, a new direct thrombin inhibitor, has been shown to be non-inferior to warfarin in protecting patients with atrial fibrillation (AF) from suffering ischemic stroke and treating patients who are afflicted with systemic thromboembolism [2,3]. It is a potent, reversible and direct competitive inhibitor of thrombin which is administered orally as a prodrug (dabigatran etexilate) and is converted to active dabigatran following its digestion from the small intestinal mucosa [4][5][6]. ...
... Dabigatran as a promising alternative to warfarin is increasingly used given its convenience to use and its capability of overcoming the cumbersome precise monitoring of INR with warfarin use. It has served as an effective agent to minimize the risk of perioperative thromboembolism [2,7,18]. As described above, however, dabigatran-induced esophagitis and the upper gastrointestinal symptoms in these patients cannot be neglected. ...
... The incidence of cerebral thromboembolic events was low with these agents and not significantly different from uninterrupted VKAs, whereas major bleeding was significantly reduced with DOACs. 2,9,10 There is still shortage of real world clinical data have evaluating the uninterrupted rivaroxaban and apixaban individually in patients undergoing AF ablation [3][4][5] . Recently, ELIMINATE -AF study compared the safety and efficacy of edoxaban with warfarin in patients undergoing AF ablation with endpoints of death, stroke or major bleeding. ...
Article
Aim: Catheter ablation in patients with atrial fibrillation (AF)/atrial flutter carries a risk of thromboembolism and major bleeding. In light of recent prospective trial data on the safety and efficacy of uninterrupted edoxaban in patients undergoing AF/flutter ablation, real-world Data was aimed for validation. Methods: A total of 228 patients who underwent AF/atrial flutter ablation over 14 months at our centre were retrospectively analyzed. All patients received uninterrupted oral anticoagulation for at least 4 weeks prior to ablation and 3 months post-ablation. Both bleeding and thromboembolic events were assessed at 24 hours comparing patients on warfarin, rivaroxaban and edoxaban. Results: Mean age of patients were 68.5 +/- 8 years in the warfarin group ( N =86), 63.4 +/- 10.6 years; in the edoxaban group ( N =63) and 62.3 +/- 11.6 years in the rivaroxaban group ( N =79). CHADSVASc scores were 2.43 +/- 1.34, 1.68 +/- 1.34 and 1.64 +/- 1.38 respectively. The mean left atrial sizes were 42.7 +/- 6.8 mm, 42.0 +/- 6 mm and 41.1 +/- 6.5 mm respectively. The study endpoint was death, acute thromboembolism or major bleeding. There was 1 pericardial effusion (1.2%) in the warfarin group, 1 pericardial effusion and 1 transient ischaemic attack (2.5%) in the rivaroxaban group and 1 pericardial effusion needing drainage (1.6%) in the edoxaban group. There were no significant differences in the study endpoints between groups. Conclusion: This real-world study demonstrated no significant difference in safety and efficacy between uninterrupted edoxaban, warfarin and rivaroxaban in patients undergoing AF/flutter ablation.
... [2] In recent years, the safety and efficacy of catheter ablation for the treatment of symptomatic AF has been clinically verified and confirmed, especially for those patients who cannot tolerate antiarrhythmia drugs or have shown no efficacy after treatment with these drugs. [3] However, left atrial thrombus (LAT)/left atrial appendage thrombus (LAAT) is a contraindication for catheter ablation. Effective anticoagulation should be performed for at least 3 weeks before catheter ablation, and the presence of LAT and LAAT should be excluded before catheter ablation. ...
Article
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Rationale: Dabigatran is a direct thrombin inhibitor that is widely used to prevent the formation of thrombus formation. Amiodarone can increase the plasma concentration of dabigatran. CES1 (carboxylesterase 1) and ABCB1 (ATP-binding cassette subfamily B member 1) genetic polymorphisms associate with the pharmacokinetics of dabigatran. Patient concerns: A 62-year-old woman was admitted to the hospital due to chest tightness, fatigue, and discomfort despite long-term anticoagulation with dabigatran 110 mg twice daily for 6 months, with concomitant use of amiodarone. Diagnoses: Left atrial appendage thrombus formation with a history of atrial fibrillation. Interventions: The clinician changed dabigatran to warfarin. To explore the causes of insufficient anticoagulation using dabigatran in this patient, we examined the ABCB1 and CES1 genes. Results showed that she carried ABCB1 variant alleles with 3 heterozygote single nucleotide polymorphisms (SNPs: rs4148738, rs1045642, rs2032582) and CES1 variant alleles with 2 heterozygote SNPs (rs2244613, rs4580160). Outcomes: The left atrial appendage thrombus disappeared. Lessons: Multiple mutations in the ABCB1 and CES1 genes may influence the pharmacokinetics of dabigatran and could have contributed to the thrombus formation in the left atrial appendage.
... Two meta-analyses comparing outcomes between dabigatran versus warfarin in the setting of catheter ablation reported no differences in bleeding or thromboembolic events. 49,50 Both analyses highlighted the limitations of nonrandomized observational study designs and variable therapeutic protocols. Within that context, the Randomized Evaluation of Dabigatran Etexilate Compared to Warfarin in Pulmonary Vein Ablation: Assessment of an Uninterupted Periprocedural Anticoagulation Strategy (RE-CIR-CUIT) trial, a randomized, controlled open-label trial examined the safety of uninterrupted dabigatran (n = 317) versus warfarin (n = 318) in patients undergoing AF ablation. ...
Article
Full-text available
As direct oral anticoagulants (DOACs) have demonstrated favorable efficacy and safety outcomes compared with vitamin K antagonists for the treatment and prevention of venous thromboembolism and the prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation, their role in the management of anticoagulation during electrophysiological procedures continues to evolve. At present, guidelines are limited regarding specific recommendations for the use of DOACs in these clinical settings. Here we review available data regarding the risks and benefits associated with various periprocedural anticoagulation management approaches when patients receiving DOACs undergo electrophysiologic procedures including cardioversion, ablation, and device implantation. This discussion is intended to provide clinicians with an overview of available evidence and best practices to minimize the risk of both thromboembolic and bleeding events in the periprocedural setting.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.
... The endothelial lesion caused by the ablation energy may serve a significant role in activating the clotting cascade. In addition, the cardioversion or the restored contractility post-ablation may dislodge left atrial microthrombi (5,6). However, minimizing thromboembolic complications with periprocedural anticoagulation could potentially increase the risk of bleeding events. ...
Article
The purpose of the present study was to compare the efficacy and safety of dabigatran and interrupted warfarin with low-molecular-weight heparin bridging in non-valvular atrial fibrillation (AF) catheter ablation. Previously, there has been concerns that bridging therapy increases bleeding events without the benefit of stroke prevention. It has been suggested that bridging therapy should be considered only for patients at high-risk of thrombosis. Nevertheless, bridging therapy in AF patients with a low CHADS2 score may be safe and effective. The authors performed a prospective, observational study that included consecutive 240 patients undergoing AF ablation in P.R. China. A total of 139 patients received 110 mg dabigatran twice daily and 101 patients took dose-adjusted warfarin that had been bridged with low-molecular-weight heparin. The mean patient age was 55.48 years with 72.1% being men and 74.2% having paroxysmal AF. One thromboembolic complication occurred in the dabigatran group compared to none in the warfarin group. Both the groups presented a similar major bleeding rate, total bleeding rate, and bleeding and thromboembolic complications. In patients undergoing AF ablation, the risk of bleeding or thromboembolic complications was similar for both dabigatran and interrupted warfarin with bridging therapy. Bridging therapy appeared to be safe and effective for the low-risk population.
... A recent meta-analysis that included 17 (1 randomised control trial, 11 retrospective observational and 5 prospective observational) studies of AF ablation (2714 patients on dabigatran and 4436 patients on warfarin) illustrated that there was no significant difference between the incidence of thrombo-embolic or bleeding complications between the two treatment arms [16]. There was significant heterogeneity in the peri-procedural dosing protocols for dabigatran used in AF ablation. ...
Article
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Left atrial ablation strategies are being increasingly performed as a Class 1 therapeutic indication for drug refractory paroxysmal atrial fibrillation (AF). Traditionally AF ablation has been performed with patients on uninterrupted warfarin therapy, however over the last few years, novel oral anticoagulants (NOACs) have emerged as attractive alternatives to warfarin in order to reduce stroke risk due to AF. NOACs are therefore increasingly being used instead of warfarin in the management of AF. There is also mounting evidence mainly in the form of small randomised studies and meta-analysis that have demonstrated that the use of NOACs for AF ablation is efficacious, safe and convenient. However the peri-procedural dosing protocols used in various studies especially in terms of whether NOAC use is interrupted or uninterrupted during AF ablation, have significant inter-operator and inter-institution variability. Currently there is also a lack of randomised controlled trials to validate the data obtained from meta-analyses. There is also evidence that use of NOACs may increase the requirement of unfractionated heparin during the procedure. This review article shall examine the currently available evidence-base, appraise the gaps in the current evidence and also underscore the need for larger randomised clinical trials in this rapidly developing field.
Article
As overall prevalence of atrial fibrillation (AF) continues to rise, the number of patients who undergo ablation, or electrical/chemical cardioversion, to restore normal sinus rhythm continues to increase as well. As direct oral anticoagulants (DOACs) have continued to be incorporated into clinical practice for long‐term anticoagulation for AF, experience with how best to manage use of DOACs during electrophysiologic procedures is evolving. This review is intended to provide health care providers with a summary of current evidence regarding the use of DOACs during cardioversion and catheter ablation and provide key considerations for their use during such electrophysiologic procedures. PubMed and Medline were searched from inception through June 2018 for studies in humans comparing DOACs alone or against vitamin K antagonists (VKAs) in adult patients (>18 years) who underwent cardioversion or AF catheter ablation using the following key words: “rivaroxaban,” “dabigatran,” “apixaban,” “edoxaban,” “non–vitamin K antagonists,” “direct or new oral anticoagulants,” “warfarin,” “vitamin K antagonists,” “cardioversion”, “ablation of atrial fibrillation,” “uninterrupted,” and “catheter ablation.” Four retrospective studies and three prospective trials comparing DOACs with VKA in patients undergoing cardioversion and three prospective studies in patients undergoing catheter ablation for AF were identified. Observational data and meta‐analyses were also critically reviewed. Prospective trials to date suggest similar efficacy and safety with using DOACs in the setting of cardioversion and AF ablation compared to traditional therapy with VKA, with or without bridging. Injectable anticoagulant overlap can be avoided in patients receiving DOACs in the setting of cardioversion for AF. Minimal interruption in anticoagulation may be only necessary for AF ablation in those with highest bleeding risk, such as in renal dysfunction and where drug‐drug interactions may increase risk for anticoagulant accumulation. Periprocedural advantages of DOACs include convenience, rapid and predictable onset of effect, improved patient satisfaction, and potential for reduced costs. This article is protected by copyright. All rights reserved.
Article
Oral anticoagulation (OAC) has been the cornerstone for the prevention of thromboembolic complications in patients with atrial fibrillation (AF) at significant risk of stroke. Catheter ablation is an established efficacious technique for the treatment of AF. Ameliorating the risk of stroke or transient ischaemic attack (TIA) in patients with AF undergoing ablation requires meticulous planning of pharmacotherapy. The advent of non-vitamin K oral anticoagulants (NOACs) has broadened the therapeutic scope, representing a viable alternative to traditional vitamin K antagonists (VKA) in non-valvular AF. Potential advantages of NOACs include greater pharmacokinetic predictability, at least comparable efficacy as compared to VKA and a superior haemorrhagic complication profile. However, robust evidence for the safety and efficacy of periprocedural NOAC use for AF ablation remains uncertain with a non-uniform clinical approach between and within institutions. The following review will summarise the current and emerging evidence on periprocedural management of NOACs in patients undergoing catheter ablation of AF. An overview of NOAC pharmacology will provide a foundation for the review of reversal agents in the context of catheter ablation of AF. The purpose of the review is to outline key studies and identify key areas for further critical research with the ultimate aim of developing evidence-based guidelines for optimal care.
Article
Scope: Introduction: Stroke can be a life-threatening complication of atrial fibrillation (AF) catheter ablation. Uninterrupted warfarin treatment contributes to minimizing the risk of stroke complications. Scope: Methods and results: This was a prospective, open-label, randomized, multicenter study assessing the safety and efficacy of apixaban for the prevention of cerebral thromboembolism complicating AF catheter ablation. Two hundred patients with drug-resistant AF were equally assigned to take either apixaban (5 mg or 2.5 mg twice daily) or warfarin (target international normalized ratio, 2 to 3) for at least 1 month before AF ablation. Neither drug regimen was interrupted throughout the operative period. Diffusion-weighted magnetic resonance imaging was performed for all patients to detect silent cerebral infarction (SCI) after the ablation. Primary outcomes were defined as the occurrence of stroke, transient ischemic attack, SCI, or major bleeding that required intervention. The secondary outcome was minor bleeding. The groups did not statistically differ in patients' backgrounds or procedural parameters. During AF ablation, the apixaban group required administration of more heparin to maintain an activated clotting time > 300 seconds than the warfarin group (apixaban, 14000 ± 4000 units; warfarin, 9000 ± 3000 units). Three primary outcome events occurred in each group (apixaban, 2 SCI and 1 major bleed; warfarin, 3 SCI, p = 1.00), and 3 and 4 secondary outcome events occurred in the apixaban and warfarin groups (p = 0.70), respectively. Scope: Conclusion: Apixaban has similar safety and effectiveness to warfarin for the prevention of cerebral thromboembolism during the periprocedural period of AF ablation. This article is protected by copyright. All rights reserved.
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Background Dabigatran etexilate, a new thrombin inhibitor, has been shown to be comparable to warfarin in patients with atrial fibrillation (AF). However, there is a limited body of evidence on the efficacy and safety of using dabigatran among patients undergoing AF catheter ablation. Objective A random effects meta-analysis was performed of controlled trials comparing dabigatran and warfarin in paroxysmal/persistent AF patients undergoing catheter ablation. Methods Data sources included Medline, Embase, and Cochrane (from inception to April 2013). Three independent reviewers selected studies comparing warfarin to dabigatran. Descriptive and quantitative information was extracted from each selected study, regarding periprocedural all cause mortality, thromboembolic events and major bleeding, as well as modalities of periprocedural anticoagulation bridging. Results After a detailed screening of 228 search results, 14 studies were identified enrolling a total of 4782 patients (1823 treated with dabigatran and 2959 with warfarin). No deaths were reported. No significant differences were found between patients treated with dabigatran and warfarin as regards thromboembolic events (0.55% dabigatran vs 0.17% warfarin; risk ratios (RR)=1.78, 95% CI 0.66 to 4.80; p=0.26) and major bleeding (1.48% dabigatran vs 1.35% warfarin; RR=1.07, 95% CI 0.51 to 2.26; p=0.86). No difference was found between the 110 mg twice daily and 150 mg twice daily dabigatran dosages concerning major bleeding (0% vs 1.62%, respectively; RR=0.19, 95% CI 0.01 to 3.18; p=0.25) and thromboembolism (0% vs 0.40%, respectively; RR=0.72, 95% CI 0.04 to 12.98; p=0.82). Conclusions In the specific setting of AF catheter ablation, this first pooled analysis suggests that patients treated with dabigatran have a similar incidence of thromboembolic events and major bleeding compared to warfarin, with low event rates overall.
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Aims Experiences with novel oral anticoagulants (NOACs) early after atrial fibrillation (AF) catheter ablation are limited and show controversial results. We aimed to assess the longer-term safety, efficacy, and acceptance of NOACs in a large real-world cohort of patients presenting for AF catheter ablation. Methods and results From July 2010 until June 2012, 259 patients undergoing AF catheter ablation were prospectively included. Novel oral anticoagulants were given for at least 3 months post-ablation. Clinical outcome (stroke, thromboembolic events, major bleeding), adverse effects, and drug adherence were assessed at discharge and follow-up. On admission patients were presented with a variety of anticoagulants including 54 patients (21%) already on NOACs prior ablation. After ablation 38% of patients received dabigatran 110 mg, 56% 150 mg, and 6% received rivaroxaban 20 mg. There were four periprocedural thromboembolic and major bleeding complications (1.5%), all in patients without NOACs prior ablation (two on warfarin and two on heparin). During long-term follow-up [311 (199; 418) days] no stroke, systemic embolism, or major haemorrhage could be observed. Uneventful electrical cardioversions and reablation procedures were performed in 27 and 12 patients on dabigatran, respectively. Novel oral anticoagulants were prematurely stopped or switched to another anticoagulant due to side effects or at the preference of the treating general practitioner in 9 and 10 patients, respectively. Conclusion In this prospective observational study, anticoagulation with NOACs following AF catheter ablation was safe and effective at long-term follow-up. Fast onset of action makes NOACs especially attractive in patients without effective anticoagulation on admission and in patients following periprocedural complications.
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The new anticoagulants dabigatran and rivaroxaban can be responsible for haemorrhagic complications. As for any anticoagulant, bleeding management is challenging. We aimed to test the effect of all putative haemostatic agents on the anticoagulant activity of these new drugs using thrombin generation tests. In an ex vivo study, 10 healthy white male subjects were randomised to receive rivaroxaban (20 mg) or dabigatran (150 mg) in one oral administration. After a two weeks washout period, they received the other anticoagulant. Venous blood samples were collected just before drug administration (H0) and 2 hours thereafter. Reversal of anticoagulation was tested in vitro using prothrombin complex concentrate (PCC), rFVIIa or FEIBA® at various concentrations. Rivaroxaban affects quantitative and kinetic parameters, including the endogenous thrombin potential (ETP-AUC and more pronouncedly the thrombin peak), the lag-time and time to peak. PCC strongly corrected ETP-AUC, whereas rFVIIa only modified the kinetic parameters. FEIBA corrected all parameters. Dabigatran specially affects the kinetics of thrombin generation with prolonged lag-time and time to peak. Although PCC increased ETP-AUC, only rFVIIa and FEIBA corrected the altered lag-time. For both anticoagulants, lower doses of FEIBA, corresponding to a quarter to half the dose usually used, have potential reversal profile of interest. In conclusion, some non-specific reversal agents appear to be able to reverse the anticoagulant activity of rivaroxaban or dabigatran. However, clinical evaluation is needed regarding haemorrhagic situations, and a meticulous risk-benefit evaluation regarding their use in this context is required.
Article
With the rapidly growing literature across the surgical disciplines, there is a corresponding need to critically appraise and summarize the currently available evidence so they can be applied appropriately to patient care. The interpretation of systematic reviews is particularly challenging in cases where few robust clinical trials have been performed to address a particular question. However, risk of bias can be minimized and potentially useful conclusions can be drawn if strict review methodology is adhered to, including an exhaustive literature search, quality appraisal of primary studies, appropriate statistical methodology, assessment of confidence in estimates and risk of bias. Therefore, the following article aims to: (I) summarize to the important features of a thorough and rigorous systematic review or meta-analysis for the surgical literature; (II) highlight several underused statistical approaches which may yield further interesting insights compared to conventional pair-wise data synthesis techniques; and (III) propose a guide for thorough analysis and presentation of results.
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Atrial fibrillation (AF) is an increasingly prevalent condition in the ageing population, with significantly associated morbidity and mortality. Surgical and catheter ablative strategies both aim to reduce mortality and morbidity through freedom from AF. This review consolidates all currently available comparative data to evaluate these two interventions. A systematic search was conducted across MEDLINE, PubMed, Embase, Cochrane Central Register of Controlled Trials and the Cochrane Database of Systematic Reviews from January 2000 until August 2013. All studies were critically appraised and only those directly comparing surgical and catheter ablation were included. Seven studies were deemed suitable for analysis according to the inclusion criteria. Freedom from AF was significantly higher in the surgical ablation group versus the catheter ablation group at 6-month, 12-month and study endpoint follow-up periods. Subgroup analysis demonstrated similar trends, with higher freedom from AF in the surgical ablation group for paroxysmal AF patients. The incidence of pacemaker implantation was higher, while no difference in stroke or cardiac tamponade was demonstrated for the surgical versus catheter ablation groups. Current evidence suggests that epicardial ablative strategies are associated with higher freedom from AF, higher pacemaker implantation rates and comparable neurological complications and cardiac tamponade incidence to catheter ablative treatment. Other complications and risks were poorly reported, which warrants further randomized controlled trials (RCTs) of adequate power and follow-up duration.
Article
Observational data suggest that performing radiofrequency catheter ablation of atrial fibrillation (AF) under therapeutic warfarin (continuous warfarin [CW]) may reduce the periprocedural risk of complications, such as thromboembolic events, compared to warfarin discontinuation (DW) with periprocedural bridging with heparin. We systematically reviewed the available evidence on the impact of CW compared with DW on periprocedural complications of AF catheter ablation. We searched major Web databases for studies on radiofrequency catheter ablation of AF under CW versus DW with periprocedural bridging with heparin. Data on periprocedural complications were extracted. We identified 9 studies (1 large case series indirectly compared with the latest Worldwide Survey). A total of 27,402 patients were included in the analysis (6400 undergoing ablation with CW). CW was associated with a striking decrease of thromboembolic complications (OR, 0.10; 95% CI, 0.05-0.23; P<0.001) and minor bleeding complications (OR, 0.38; 95% CI, 0.21-0.71; P=0.002) compared with DW. CW also did not increase the risk of major bleeding (OR, 0.67; 95% CI, 0.31-1.43; P=0.30), including cardiac tamponade (OR, 0.69; 95% CI, 0.19-2.47; P=0.57). There is highly consistent evidence from observational studies that a CW strategy during radiofrequency catheter ablation of AF reduces the risk of thromboembolic complications without increasing the risk of bleeding.
Article
Radiofrequency left atrial catheter ablation has become a routine procedure for treatment of atrial fibrillation. The aim of this study was to assess with preprocedural and postprocedural cerebral magnetic resonance imaging the thromboembolic risk, either silent or clinically manifest, in the context of atrial fibrillation ablation. The secondary end point was the identification of clinical or procedural parameters that correlate with cerebral embolism. A total of 232 consecutive patients with paroxysmal or persistent atrial fibrillation who were candidates for radiofrequency left atrial catheter ablation were included in the study. Pulmonary vein isolation or pulmonary vein isolation plus linear lesions plus atrial defragmentation with the use of irrigated-tip ablation catheters was performed. All of the patients underwent preprocedural and postablation cerebral magnetic resonance imaging. A periprocedural symptomatic cerebrovascular accident occurred in 1 patient (0.4). Postprocedural cerebral magnetic resonance imaging was positive for new embolic lesions in 33 patients (14). No clinical parameters such as age, hypertension, diabetes mellitus, previous history of stroke, type of atrial fibrillation, and preablation antithrombotic treatment showed significant correlation with ischemic cerebral embolism. Procedural parameters such as activated clotting time value and, in particular, electric or pharmacological cardioversion to sinus rhythm correlated with an increased incidence of cerebral embolism. Cardioversion was also associated with an increased risk of 2.75 (95 confidence interval, 1.29 to 5.89; P=0.009). Radiofrequency left atrial catheter ablation carries a low risk of symptomatic cerebral ischemia but is associated with a substantial risk of silent cerebral ischemia detected on magnetic resonance imaging. Independent risk factors for cerebral thromboembolism are the level of activated clotting time and, in particular, the electric or pharmacological cardioversion to sinus rhythm during the procedure.
Article
The aim of this multicenter study was to evaluate the safety of discontinuing oral anticoagulation therapy (OAT) after apparently successful pulmonary vein isolation. Atrial fibrillation (AF) is associated with an increased risk of thromboembolic events (TE) and often requires OAT. Pulmonary vein isolation is considered an effective treatment for AF. We studied 3,355 patients, of whom 2,692 (79% male, mean age 57 +/- 11 years) discontinued OAT 3 to 6 months after ablation (Off-OAT group) and 663 (70% male, mean age 59 +/- 11 years) remained on OAT after this period (On-OAT group). CHADS(2) (congestive heart failure, hypertension, age [75 years and older], diabetes mellitus, and a history of stroke or transient ischemic attack) risk scores of 1 and > or =2 were recorded in 723 (27%) and 347 (13%) Off-OAT group patients and in 261 (39%) and 247 (37%) On-OAT group patients, respectively. During follow-up (mean 28 +/- 13 months vs. 24 +/- 15 months), 2 (0.07%) Off-OAT group patients and 3 (0.45%) On-OAT group patients had an ischemic stroke (p = 0.06). No other thromboembolic events occurred. No Off-OAT group patient with a CHADS(2) risk score of > or =2 had an ischemic stroke. A major hemorrhage was observed in 1 (0.04%) Off-OAT group patient and 13 (2%) On-OAT group patients (p < 0.0001). In this nonrandomized study, the risk-benefit ratio favored the suspension of OAT after successful AF ablation even in patients at moderate-high risk of TE. This conclusion needs to be confirmed by future large randomized trials.
Article
Catheter ablation has evolved as an effective treatment modality in patients with AF. In this review, the rationale and outcomes of ablation strategies targeting various mechanisms of AF based on our current understanding are discussed. Likely mechanisms responsible for the therapeutic effects of these approaches are reviewed.