2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Patients With Atrial Fibrillation" provides recommendations to guide clinicians in the treatment of patients with atrial fibrillation.

METHODS

A comprehensive literature search was conducted from May 12, 2022, to November 3, 2022, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through November 2022, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Atrial fibrillation is the most sustained common arrhythmia, and its incidence and prevalence are increasing in the United States and globally. Recommendations from the "2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" and the "2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing atrial fibrillation and thromboembolic risk assessment, anticoagulation, left atrial appendage occlusion, atrial fibrillation catheter or surgical ablation, and risk factor modification and atrial fibrillation prevention have been developed.

2020 ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

This executive summary of the valvular heart disease guideline provides recommendations for clinicians to diagnose and manage valvular heart disease as well as supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from January 1, 2010, to March 1, 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, Cochrane, Agency for Healthcare Research and Quality Reports, and other selected database relevant to this guideline. Structure: Many recommendations from the earlier valvular heart disease guidelines have been updated with new evidence and provides newer options for diagnosis and treatment of valvular heart disease. This summary includes only the recommendations from the full guideline which focus on diagnostic work-up, the timing and choice of surgical and catheter interventions, and recommendations for medical therapy. The reader is referred to the full guideline for graphical flow charts, text, and tables with additional details about the rationale for and implementation of each recommendation, and the evidence tables detailing the data considered in developing these guidelines.

Treatment Complications of Atrial Fibrillation and Their Management

Atrial fibrillation (AF) is a rhythm disturbance defined by irregular, rapid electrical, and mechanical activation of the atria, which causes unsynchronized atrial contraction and promotes thromboembolism. AF is the most common sustained arrhythmia. Its prevalence and incidence are increasing due to aging and improved survival from acute heart diseases. This article is a review on AF management from both a surgical and catheter-based perspective. While both treatment approaches to AF have been shown to be successful in the management of AF, they are not without their own inherent complications. This article seeks to review some of these complications and help to guide treatment.

Efficacy and safety of rivaroxaban on the resolution of left atrial/left atrial appendage thrombus in nonvalvular atrial fibrillation patients

Data on LA/LAA thrombus resolution after rivaroxaban treatment has not been established. The aim of the present study was to compare the efficacy and safety on the resolution of LA/LAA thrombus between rivaroxaban and warfarin in nonvalvular atrial fibrillation (AF) patients. 80 AF patients with LA/LAA thrombus between January 2013 and June 2016 were randomized divided into warfarin group (n = 40) and rivaroxaban group (n = 40). Compared to warfarin group, thrombin time (TT; p < 0.0001), plasma prothrombin time (PT; p < 0.0001), and activated partial thromboplastin time (APTT; p = 0.0019) were significantly lower, and fibrinogen (FIB; p < 0.0001) was significantly higher in rivaroxaban group. TEE shown the average length (p < 0.0001), average width (p = 0.0008) and average area (p < 0.0001) of thrombus were significantly lower in rivaroxaban group compared to warfarin group after 6-week treatments. No major or fatal bleeding and ischemic stroke occurred in both two groups. The 20 mg dose Rivaroxaban is more effective than warfarin on the resolution of LA/LAA thrombus in nonvalvular AF patients especially after 6-week treatments. The results suggest that rivaroxaban is a potential option for the treatment of LA/LAA thrombus in patients with nonvalvular AF.

Metabolic benefits of rivaroxaban in non-valvular atrial fibrillation patients after radiofrequency catheter ablation

BACKGROUND AND OBJECTIVE

Rivaroxaban is a new oral anticoagulant for stroke prevention in patients with non-valvular atrial fibrillation (NVAF), which has less drug-food interaction than warfarin. We conducted this prospective randomized study to evaluate the metabolic benefits as well as the safety and efficacy with rivaroxaban versus warfarin in patients with NVAF following radiofrequency catheter ablation (RFCA).

METHODS

From April to July 2014, 60 patients with NVAF undergoing RFCA were prospectively enrolled in our study. Following RFCA, all patients were randomly assigned to receive rivaroxaban (Group R, n=30) or warfarin (Group W, n=30). Metabolic indices including serum total protein, albumin, globulin, and high-density lipoprotein (HDL) as well as bleeding, stroke, and systemic thromboembolism events were evaluated and compared during follow-up after 15, 30, 60, and 90 d of RFCA procedure.

RESULTS

Serum total protein, albumin, globulin, and HDL levels were all significantly elevated at each follow-up stage in Group R when compared to the baseline (P<0.05 respectively). In Group W, the metabolic indices decreased at first and then had an increasing trend. There were no deaths or thromboembolic complications in each group. The prevalence of total bleeding complications was similar between Group R and Group W (11/30, 36.7% vs. 10/30, 33.3%, P=0.79).

CONCLUSIONS

Patients with NVAF receiving rivaroxaban after RFCA procedures appear to benefit from a metabolic perspective compared with warfarin, providing practical clinical reference for the choice of the anticoagulant. Rivaroxaban seems to be as safe and effective in preventing thromboembolic events as warfarin for these patients.

Choosing a particular oral anticoagulant and dose for stroke prevention in individual patients with non-valvular atrial fibrillation: part 1

Patients with atrial fibrillation (AF) have a high risk of stroke and mortality, which can be considerably reduced by oral anticoagulants (OAC). Recently, four non-vitamin-K oral anticoagulants (NOACs) were compared with warfarin in large randomized trials for the prevention of stroke and systemic embolism. Today's clinician is faced with the difficult task of selecting a suitable OAC for a patient with a particular clinical profile or a particular pattern of risk factors and concomitant diseases. We reviewed analyses of subgroups of patients from trials of vitamin K antagonists vs. NOACs for stroke prevention in AF with the aim to identify patient groups who might benefit from a particular OAC more than from another. In the first of a two-part review, we discuss the choice of NOAC for stroke prevention in the following subgroups of patients with AF: (i) stable coronary artery disease or peripheral artery disease, including percutaneous coronary intervention with stenting and triple therapy; (ii) cardioversion, ablation and anti-arrhythmic drug therapy; (iii) mechanical valves and rheumatic valve disease, (iv) patients with time in therapeutic range of >70% on warfarin; (v) patients with a single stroke risk factor (CHA2DS2VASc score of 1 in males, 2 in females); and (vi) patients with a single first episode of paroxysmal AF. Although there are no major differences in terms of efficacy and safety between the NOACs for some clinical scenarios, in others we are able to suggest that particular drugs and/or doses be prioritized for anticoagulation.

How safe are NOACs compared with phenprocoumon after pulmonary vein isolation with the cryoballoon technique using purse-string suture closure?

INTRODUCTION

The aim of this observational study was to compare the postprocedural incidence of bleeding and thromboembolic complications associated with novel oral anticoagulants (NOACs) with that of interrupted and continuous phenprocoumon after pulmonary vein isolation (PVI) using a purse-string suture (PSS) closure of the puncture site.

METHODS AND RESULTS

Consecutive patients who had undergone PVI via cryoballoon ablation were divided into the following groups: (1) interrupted phenprocoumon with heparin bridging (n=101), (2) continuous phenprocoumon targeting an internationally normalized ratio>2 (n=70), and (3) NOACs without bridging that were restarted 2-4h after the procedure (n=185). Protamine was not administered after venous closure with PSS at the end of the procedure. The total complication rate was significantly lower in group 3 than in groups 1 and 2 (1.62% vs. 6.93% vs. 7.14%, p=0.04). The hospital costs were lower and the hospital stay length was significantly shorter (4484±3742 vs. 6082±4044 Euro vs. 4908±2925, p=0.03; 1.94±1.67 vs. 2.70±1.80 vs. 2.19±1.30days, p<0.01). No thromboembolic event occurred. Vascular complications were the most common complications noted (80%). The occurrence of any complication led to a significantly longer hospital stay (5 vs. 2days, p<0.01) and higher costs (10,052±6241 Euro vs. 4747±3447, p<0.01). The vascular complication rate after PSS was independent of intraprocedural heparin dosage and activated clotting time.

CONCLUSIONS

NOACs have a lower complication rate and appear to be safer in this setting than phenprocoumon. The hospital costs and hospital stay length after PVI was significantly reduced in patients treated with NOACs compared with phenprocoumon.

Perioperative management of patients on direct oral anticoagulants

Direct oral anticoagulants (DOACs) have been licensed worldwide for several years for various indications. Each year, 10-15% of patients on oral anticoagulants will undergo an invasive procedure and expert groups have issued several guidelines on perioperative management in such situations. The perioperative guidelines have undergone numerous updates as clinical experience of emergency management has increased and perioperative studies including measurement of residual anticoagulant levels have been published. The high inter-patient variability of DOAC plasma levels has challenged the traditional recommendation that perioperative DOAC interruption should be based only on the elimination half-life of DOACs, especially before invasive procedures carrying a high risk of bleeding. Furthermore, recent publications have highlighted the potential danger of heparin bridging use when DOACs are stopped before an invasive procedure. As antidotes are progressively becoming available to manage severe bleeding or urgent procedures in patients on DOACs, accurate laboratory tests have become the standard to guide their administration and their actions need to be well understood by clinicians. This review aims to provide a systematic approach to managing patients on DOACs, based on recent updates of various perioperative guidance, and highlighting the advantages and limits of recommendations based on pharmacokinetic properties and laboratory tests.

Atrial fibrillation: review of current treatment strategies

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.

Early Experience of Novel Oral Anticoagulants in Catheter Ablation for Atrial Fibrillation: Efficacy and Safety Comparison to Warfarin

PURPOSE

Compared with warfarin, novel oral anticoagulants (NOACs) are convenient to use, although they require a blanking period immediately before radiofrequency catheter ablation for atrial fibrillation (AF). We compared NOACs and uninterrupted warfarin in the peri-procedural period of AF ablation.

MATERIALS AND METHODS

We compared 141 patients treated with peri-procedural NOACs (72% men; 58 ± 11 years old; 71% with paroxysmal AF) and 281 age-, sex-, AF type-, and history of stroke-matched patients treated with uninterrupted warfarin. NOACs were stopped 24 hours before the procedure and restarted on the same procedure day after hemostasis was achieved.

RESULTS

We found no difference in the CHA₂DS₂-VASc (p=0.376) and HAS-BLED scores (p=0.175) between the groups. The preprocedural anticoagulation duration was significantly shorter in the NOAC group (76.3 ± 110.7 days) than in the warfarin group (274.7 ± 582.7 days, p<0.001). The intra-procedural total heparin requirement was higher (p<0.001), although mean activated clotting time was shorter (350.0 ± 25.0 s vs. 367.4 ± 42.9 s, p<0.001), in the NOAC group than in the warfarin group. There was no significant difference in thromboembolic events (1.4% vs. 0%, p=0.111) or major bleeding (1.4% vs. 3.9%, p=0.235) between the NOAC and warfarin groups. Minor stroke occurred in two cases within 10 hours of the procedure (underlying CHA₂DS₂-VASc scores 0 and 1) in the NOAC group.

CONCLUSION

Pre-procedural anticoagulation duration was shorter and intra-procedural heparin requirement was higher with NOAC than with uninterrupted warfarin during AF ablation. Although the peri-procedural thromboembolism and bleeding incidences did not differ, minor stroke occurred in two cases in the NOAC group.

Apixaban, Rivaroxaban, and Dabigatran in Patients Undergoing Atrial Fibrillation Ablation

INTRODUCTION

Data on the novel oral anticoagulants (NOACS) during catheter ablation (CA) of atrial fibrillation (AF) are still limited. This study evaluated the periprocedural major complications (MC) of CA of AF, and compared Apixaban, Dabigatran, and Rivaroxaban with continuous phenoprocoumon.

METHODS AND RESULTS

A total of 444 patients (mean age = 65.1 ± 9.4 years; 283 [64%] male) with paroxysmal (n = 180 [41%]), persistent (n = 256 [58%]), or longstanding-persistent AF were enrolled. CA was performed in all patients using radiofrequency energy in conjunction with a 3D-mapping system. MCs were defined according to the current guidelines. Continuous phenprocoumon-therapy was administered in 120/444 (27%) patients (group 1) and 324/444 (73%) patients were treated with NOACs (group 2; Dabigatran: n = 51 [15.7%]; Rivaroxaban: n = 193 [59.6%]; Apixaban: n = 80 [24.7%]). Procedure times were comparable between groups 1 and 2 (128.2 ± 39.7 minutes vs. 129.7 ± 51.2 minutes; P = 0.77). CHA2 DS2-Vasc (3.0 [2.0, 4.0)] vs. 2.0 [1.0, 3.0]; P < 0.01) and HASBLED scores (2.0 [2.0, 2.5] vs. 2.0 [1.0, 2.0]; P = 0.002) were higher in group 1 patients. The incidence of MCs in the overall group was 8/444 (2%) and was equally distributed between groups 1 and 2 (2/120 [2%] vs. 6/324 [2%], P = 0.90). The incidence of MCs was comparable between the three different NOACs. There were no significant differences between patients with and without MCs with regard to age, CHA2 DS2-Vasc-score or HASBLED-score.

CONCLUSIONS

The major complication rate between all three NOACs currently available and continuous phenprocoumon during AF ablation seem to be comparable. Complication rates were similar between patients treated with the three different available NOACs.

Bleeding risks with novel oral anticoagulants during catheter ablation of atrial fibrillation: a systematic review and network meta-analysis

BACKGROUND

Comprehensive comparisons of safety (measured by bleeding risk) between multiple novel oral anticoagulants (NOACs and warfarin) in the peri-procedural period of catheter ablation (CA) for atrial fibrillation (AF) are rare.

METHODS AND RESULTS

MEDLINE, EMBASE, and COCHRANE LIBRARY were searched up to February 2015 by two reviewers independently. Predefined inclusion criteria identified 24 studies which were included in the analysis. Data were extracted by two researchers, and a network meta-analysis was conducted in R with R2WinBugS package, within Bayesian framework. Pooled odds ratios (OR) and 95% confidence intervals (CI) were summarized to evaluate the bleeding risks of three novel anticoagulants (dabigatran, rivaroxaban, apixaban) in AF patients undergoing catheter ablation (CA). With respect to total bleeding risk, no significant difference was observed between dabigatran, rivaroxaban, apixaban, and vitamin K antagonists (VKAs) by mixed-treatment comparison. The similar results were seen in the direct comparison. While dabigatran was associated with a lower rate of minor bleeding in comparison to VKAs (OR = 0.67 with 95%CI 0.49-0.93).

CONCLUSIONS

Risks of bleeding with dabigatran, rivaroxaban, apixaban, and VKAs were similar in peri-procedural period of CA for AF.

New oral anticoagulants in patients undergoing atrial flutter radiofrequency catheter ablation: an observational study

AIM

Atrial flutter (AFL) ablation requires optimal periprocedural anticoagulation in order to minimize thromboembolic events/bleeding risk. This study describes the characteristics of patients receiving new oral anticoagulants before AFL ablation and assesses complications.

METHODS

This multicenter, retrospective study reports ischemic and hemorrhagic predischarge, postprocedural complications.

RESULTS

We evaluated 60 patients (62.3% male; mean age: 69.2 ± 9.7 years; CHA2DS2-VASc score: 2.44 ± 1.46, HAS-BLED score: 1.14 ± 0.7). Twenty-one (35.0%) and 23 patients (38.3%) received twice-daily dabigatran 110 or 150 mg; 16 patients (26.6%) received once-daily rivaroxaban (15 mg [n = 5] or 20 mg [n = 11]). Four cases of postprocedural minor bleeding were reported.

CONCLUSION

This is the first study assessing new oral anticoagulants for periprocedural anticoagulation, specifically in patients undergoing AFL ablation. No major bleeding was reported. Further prospective investigation is warranted.

Periprocedural Management of New Oral Anticoagulants in Atrial Fibrillation Ablation

BACKGROUND

Patients who undergo catheter ablation for atrial fibrillation (AF) are at increased risk of developing thromboembolic and bleeding complications periprocedurally. Many patients are now on newer oral anticoagulants (NOACs), but data regarding their safety and efficacy during AF ablation are limited.

METHODS AND RESULTS

This article reviews the literature in PubMed from 1998 to 2014 and includes clinical trials and meta-analysis that analyzed the safety and efficacy of NOACs during AF catheter ablation. Dabigatran seems to be as effective and safe as warfarin, although most data are from single-center studies, with small samples and very low overall bleeding and thromboembolic complications. Periprocedural anticoagulation protocols also vary greatly between studies. Some recent meta-analysis has shown that warfarin could still be a safer and more effective alternative. There are fewer studies with rivaroxaban in AF ablation, and there have been no meta-analysis yet comparing rivaroxaban to warfarin or dabigatran. There seems to be no significant differences in safety or efficacy of rivaroxaban compared to warfarin. Interestingly, there are no available data for apixaban in AF ablation yet.

DISCUSSION

There are no consensus guidelines regarding the use of NOACs during AF ablation. Dabigatran and rivaroxaban seem as safe and effective as warfarin, although larger studies with standardized protocols are needed, as available studies may be underpowered to detect small differences in bleeding and thromboembolic rates.

Meta-analysis of risk of stroke and thrombo-embolism with rivaroxaban versus vitamin K antagonists in ablation and cardioversion of atrial fibrillation

BACKGROUND

Anticoagulation in cardioversion and ablation of atrial fibrillation is imperative for reducing thrombo-embolic events. Ample information is available about the use of warfarin and vitamin K antagonists (VKA) but few trials examine safety and efficacy of rivaroxaban in these procedures. We aim to explore the hypothesis that rivaroxaban causes equal thrombo-embolic and bleeding events when used in atrial fibrillation patients undergoing ablation or cardioversion compared to VKA.

METHODS

We searched the online databases as well as conference abstracts till December 2014 for studies comparing rivaroxaban with VKA in atrial fibrillation patients undergoing catheter ablation or cardioversion. We report events as Odds ratio using random effects model except when event rates were less than 1% we used Peto Odds Ratio.

RESULTS

A total of 8872 atrial fibrillation patients in 15 studies undergoing either catheter ablation or cardioversion were included in this analysis. There were significantly lower stroke events with rivaroxaban compared with VKA (Peto Odds Ratio (POR) 0.33, 95% confidence interval (CI) [0.11, 0.95]; P=0.04), and significantly less thrombo-embolic events with rivaroxaban compared with VKA (POR 0.46, 95% CI [0.21, 0.97]; P=0.04). Major and minor bleeding were equal with rivaroxaban versus VKA (Odds Ratio (OR) 0.92, 95% CI [0.62, 1.36]; P=0.68) and (OR 0.81,95% CI [0.58, 1.11]; P=0.19) respectively.

CONCLUSION

The use of rivaroxaban in ablation and cardioversion of atrial fibrillation may be associated with decreased risk of stroke and thromboembolism with equal bleeding risk compared to VKA.

Practical issues in the management of novel oral anticoagulants-cardioversion and ablation

Recent research and publication of various landmark trials have led to the approval and subsequent use of novel oral anticoagulants (NOACs) in clinical practice. The use of these newer agents for anticoagulation offers several benefits such as greater specificity, relatively rapid onset and offset of action and a predictable pharmacological profile as compared to warfarin. With the increasing use of these agents, several key issues ranging from appropriate selection to management of complications and considerations for concurrent procedures (cardioversion and catheter ablation) have also emerged. The timing of interruption of anticoagulants prior to catheter ablation and re-initiation after the procedure to minimize the peri-procedural thromboembolism risk without increasing the bleeding risk is of key relevance in electrophysiology practice. The use of NOACs in patients undergoing catheter ablation and cardioversion also requires special considerations based on the pharmacological properties of the individual agent and the presence of comorbidities such as renal and or hepatic impairment. In this review we aim to discuss the practical considerations with the use of NOACs in the setting of cardioversion and catheter ablation based on the currently available data.

Safety of Novel Oral Anticoagulants Compared With Uninterrupted Warfarin for Catheter Ablation of Atrial Fibrillation

Background: The novel oral anticoagulants (NOACs) are used for stroke prevention in atrial fibrillation (AF), but their safety and efficacy in the periablation period are not well established. Additionally, no standard procedure for managing periprocedural and intraprocedural anticoagulation has been established. Objective: To evaluate the frequency of hemorrhagic and thrombotic events as well as periprocedural management strategies of NOACs compared with warfarin as anticoagulation therapy for AF ablation. Methods: This was a retrospective cohort study from a prospective AF ablation registry maintained at a large, academic medical center. Results: A total of 374 cases (173 warfarin, 123 dabigatran, 61 rivaroxaban, and 17 apixaban) were included in the analysis. The overall hemorrhagic/thrombotic event rate was 14.2 % (major hemorrhage 2.7%, minor hemorrhage 11.2%, thrombotic stroke 0.5%). The frequency of minor hemorrhage was significantly higher with warfarin compared with dabigatran (15% vs 5.7%, P = 0.012). The average heparin dose required to reach the goal activated clotting time (ACT) was 5600 units for warfarin, 12 900 units for dabigatran ( P < 0.001), 15 100 units for rivaroxaban ( P < 0.001), and 14 700 units for apixaban ( P < 0.001). The average time in minutes to reach the goal ACT was significantly longer, compared with warfarin, for dabigatran (57 vs 28, P < 0.001), rivaroxaban (63 vs 28, P < 0.001), and apixaban (72 vs 28, P < 0.001). Conclusions: Compared with warfarin, periprocedural anticoagulation with dabigatran resulted in fewer minor hemorrhages and total adverse events after AF ablation. Patients anticoagulated with NOACs required larger doses of heparin and took longer to reach the goal ACT compared with patients anticoagulated with warfarin.

Warfarin versus dabigatran etexilate: an assessment of efficacy and safety in patients with atrial fibrillation

INTRODUCTION

Oral anticoagulation is the mainstay for stroke and thromboembolic event prevention in patients with atrial fibrillation (AF). Given limitations of warfarin therapy, non-vitamin K oral anticoagulants have been developed including direct thrombin inhibitors (i.e., dabigatran etexilate). Dabigatran etexilate has been tested thoroughly in terms of efficacy and safety in clinical trials and studies, involving 'real-world' cohorts. In this review, currently available evidence in patients with non-valvular AF is discussed.

AREAS COVERED

The pharmacology, efficacy and safety, and current aspects of use of dabigatran etexilate in patients with non-valvular AF are reviewed in a comparative manner to warfarin both for chronic anticoagulation and in different clinical settings.

EXPERT OPINION

Dabigatran etexilate appeared to have several pharmacokinetic and pharmacodynamic advantages over warfarin, as well as a favorable efficacy and safety profile being at least noninferior and often superior to warfarin in patients with non-valvular AF. The latter was shown in the clinical trials, meta-analyses and studies with 'real-world' data. Currently ongoing trials will expand the body of evidence on warfarin and will aid decision making in currently controversial areas. Important limitations of dabigatran etexilate include contraindications for its use in patients with prosthetic heart valves and end-stage chronic kidney disease.

A clinician's perspective: novel oral anticoagulants to reduce the risk of stroke in nonvalvular atrial fibrillation--full speed ahead or proceed with caution?

Over the past few years, three novel oral anticoagulants, dabigatran, rivaroxaban, and apixaban, have been approved in the USA and Europe to reduce the risk of stroke or systemic embolism in patients with nonvalvular atrial fibrillation, and the results of a Phase III trial for a fourth novel oral anticoagulant, edoxaban, have recently been published. The aim of this review is to examine this indication from a clinician's perspective, highlighting efficacy and safety results from the major trials with these novel oral agents. Clinical issues regarding bleeding, monitoring, and reversal are discussed, along with requirements to consider when interrupting treatment with a novel oral anticoagulant for the purpose of transitioning to another anticoagulant and prior to cardioversion, ablation, percutaneous coronary intervention, or emergency surgery. The cost-effectiveness of each of the approved novel oral anticoagulants is reviewed, and the author provides recommendations for selecting appropriate patients for these agents.

Meta-analysis of efficacy and safety of rivaroxaban compared with warfarin or dabigatran in patients undergoing catheter ablation for atrial fibrillation

Several studies have been conducted to study the efficacy and safety of rivaroxaban in the atrial fibrillation periprocedural ablation period with similar rates of thromboembolism and major bleeding risks compared with warfarin or dabigatran. We sought to systematically review this evidence using pooled data from multiple studies. Studies comparing rivaroxaban with warfarin or dabigatran in patients undergoing catheter ablation for atrial fibrillation were identified through electronic literature searches of MEDLINE, EMBASE, clinicaltrials.gov, and the Cochrane library up to March 2014. Study-specific risk ratios (RRs) were calculated and combined using a random-effects model meta-analysis. In an analysis involving 3,575 patients, thromboembolism (composite of stroke, transient ischemic attack, and systemic and pulmonary emboli) occurred in 3 of 789 patients (0.4%) in the rivaroxaban group and 10 of 2,786 patients (0.4%) in the warfarin group (RR 0.71, 95% CI 0.26 to 1.96, I(2) = 0%, p = 0.51). Major hemorrhage occurred in 9 of 749 patients (1.2%) in the rivaroxaban group and 22 of 975 patients (2.3%) in the warfarin group (RR 0.49, 95% CI 0.24 to 1.02, I(2) = 0%, p = 0.06). Furthermore, direct efficacy and safety comparisons between rivaroxaban and dabigatran showed nonsignificant differences in rates of thromboembolism (0.5% vs 0.4%, respectively, RR 1.12, 95% CI 0.25 to 4.99, I(2) = 0%, p = 0.88) and major bleeding (1.0% vs 1.6%, respectively, RR = 0.71, 95% CI 0.16 to 3.15, I(2) = 22%, p = 0.66). In conclusion, our study suggests that patients treated with rivaroxaban during periprocedural catheter ablation have similar rates of thromboembolic events and major hemorrhage. Similar results were seen in direct comparisons between dabigatran and rivaroxaban.

Safety of Continuous Periprocedural Rivaroxaban for Patients Undergoing Left Atrial Catheter Ablation Procedures

Background—

This study aimed to evaluate the safety of continuous periprocedural rivaroxaban administration during left atrial radiofrequency ablation (RFA) in comparison with uninterrupted oral vitamin K antagonist administration. Data about the use of rivaroxaban in the setting of left atrial RFA procedures are lacking.

Methods and Results—

The study cohort included 544 patients (mean age, 63±10 years) who underwent left atrial RFA procedures between February 2012 and May 2013. All patients (n=272) receiving uninterrupted periprocedural rivaroxaban 15 or 20 mg/d before the procedure (rivaroxaban) were matched by age, sex, and type of rhythm disorder with an equal number of patients managed with uninterrupted vitamin K antagonist phenprocoumon (international normalized ratio, 2–3). During RFA, heparin was given intravenously to maintain an activated clotting time at 270 to 300 s. The safety end point was a composite of bleeding, thromboembolic events, and death. There were no thromboembolic complications and no deaths in either group. The prevalence of major bleeding complications was similar in both groups (1 tamponade in RivG and 1 groin hematoma requiring transfusion in phenprocoumon). Minor bleeding complications occurred equally in both groups (20 of 272; 7% in the rivaroxaban versus 33 of 272, 12% in the phenprocoumon; P =0.08). In multivariable analyses, female sex was associated with a greater risk of complications (odds ratio, 1.96; 95% confidence interval, 1.10–3.49).

Conclusions—

In patients undergoing left atrial RFA, continuous periprocedural rivaroxaban use seems to be as safe as uninterrupted periprocedural phenprocoumon administration.

Catheter ablation of atrial fibrillation: an update

Catheter ablation of atrial fibrillation (AF) is now an important therapeutic modality for patients with AF. There is considerable evidence available from several prospective randomized trials demonstrating that catheter ablation of AF is superior to antiarrhythmic drug therapy in controlling AF and that AF ablation improves quality of life substantially. This is especially true for patients with paroxysmal AF without other severe comorbidities. Catheter ablation is indicated for treatment of patients with symptomatic AF in whom one or more attempts at class 1 or 3 antiarrhythmic drug therapy have failed. Although current guidelines state that is appropriate to perform catheter ablation as a first-line therapy in selected patients, in our clinical practice this is rare. This reflects a number of important realities concerning the field of AF ablation. Catheter ablation of AF is a challenging and complex procedure, which is not free of the risk of potentially life-threatening complications, such as an atrio-oesophageal fistula, stroke, and cardiac tamponade. Although these major complications are rare and their rate is falling, they must be considered by both patients and physicians. The progress made and the new developments on the horizon in the field of AF catheter ablation are remarkable. When radiofrequency catheter ablation was first introduced in the late 1980s, few would have predicted that catheter ablation of AF would emerge as the most commonly performed ablation procedure in most major hospitals.