Safety of percutaneous left atrial appendage closure: results from the Watchman Left Atrial Appendage System for Embolic Protection in Patients with AF (PROTECT AF) clinical trial and the Continued Access Registry

The WATCHMAN device for stroke prophylaxis in atrial fibrillation: an evolving niche

Atrial fibrillation is associated with a markedly increased risk of thromboembolic stroke. At present, lifelong antithrombotic therapy with warfarin or a novel oral anticoagulant is indicated for prophylaxis in the majority of patients. Left atrial appendage occlusion devices have been developed as an alternative to these agents, aiming to avoid issues around consistency of anticoagulation, bleeding risk, and drug-related side effects. The best evidence is available for Boston Scientific's WATCHMAN device. The safety and efficacy of WATCHMAN and other similar devices have been questioned, although the increasing body of evidence supports a role in selected settings. A recently updated randomized controlled trial of WATCHMAN (WATCHMAN Left Atrial Appendage System for Embolic PROTECTion in Patients with Atrial Fibrillation [PROTECT-AF]) demonstrates its noninferiority to warfarin and suggests an advantage in terms of functional outcome for patients, with superior net clinical benefit 6 to 9 months after starting treatment. The procedural risk associated with device implantation remains substantial, although improving device design and increasing operator experience means that this should decrease in the future. As the body of data and overall experience around WATCHMAN grow, it may come to be recognized as the best option in selected patients.

Modern treatment of atrial fibrillation

Atrial fibrillation (AF) is the most common type of arrhythmia and has a large global burden. In general, treatment of AF is based on medication and consists of rate and rhythm control together with anticoagulation. However, surgical treatment may be required in patients with AF combined with organic valvular heart diseases or who experience recurrence despite medication. In addition, surgical treatment plays a role in the treatment of lone AF. This article reviews the various surgical treatment options for AF.

Utilization and adverse outcomes of percutaneous left atrial appendage closure for stroke prevention in atrial fibrillation in the United States: influence of hospital volume

BACKGROUND

Safety data on percutaneous left atrial appendage closure arises from centers with considerable expertise in the procedure or from clinical trial, which might not be reproducible in clinical practice. We sought to estimate the frequency and predictors of adverse outcomes and costs of percutaneous left atrial appendage closure procedure in the US.

METHODS AND RESULTS

The data were obtained from the Nationwide Inpatient Sample from the years 2006 to 2010. The Nationwide Inpatient Sample is the largest all-payer inpatient data set in the US. Complications were calculated using patient safety indicators and International Classification of Diseases-Ninth Revision, Clinical Modification codes. Annual hospital volume was calculated using unique hospital identifiers. Weights provided by the Nationwide Inpatient Sample were used to generate national estimates. A total of 268 (weighted=1288) procedures were analyzed. The overall composite rate of mortality or any adverse event was 24.3% (65), with 3.4% patients required open cardiac surgery after procedure. Average length of stay was 4.61±1.05 days and cost of care was 26,024±34,651. Annual hospital procedural volume was significantly associated with reduced complications and mortality (every unit increase: odds ratio, 0.89; 95% confidence interval, 0.85-0.94; P<0.001), decrease in length of stay (every unit increase: hazard ratio, 0.95; 95% confidence interval, 0.92-0.98; P<0.001) and cost of care (every unit increase: hazard ratio, 0.96; 95% confidence interval, 0.93-0.98; P<0.001).

CONCLUSIONS

Our study demonstrates that the frequency of inhospital adverse outcomes associated with percutaneous left atrial appendage closure is higher in the real-world population than in clinical trials. We also demonstrate that higher annual hospital volume is associated with safer procedures, with lower length of stay and cost.

[Proper use of apixaban: an outline for clinical practice]

Apixaban is a direct inhibitor of coagulation factor Xa. Superior efficacy over aspirin and antivitamin K has been shown in the prevention of stroke and systemic embolism during non-valvular atrial fibrillation with a more favorable safety profile, even though the risk of hemorrhage cannot be ignored, considering its mechanism of action. The recommended dose is 5mg twice daily which can be reduced to 2.5mg depending on the individual risk. Apixaban is also indicated for the treatment of venous thromboembolism but reimbursement has not yet been accepted in France for this indication. As with all direct oral anticoagulants, no routine biological monitoring is required, nevertheless their use may have an impact on all coagulation tests, eventually hampering interpretation. In particular clinical circumstances where a measure of anticoagulant efficacy is deemed necessary, specific assay of anti-Xa activity is appropriate, the result being expressed as concentration of the anticoagulant used. It is therefore necessary to state the name of the medicine for which the assay is requested. With these new anticoagulants, management of hemorrhagic events can be more difficult due to the lack of a specific antidote. Pro-hemostatic substances have exhibited efficacy in animal models but results are still insufficiently documented in clinical practice. Local or locoregional hemostasis measurements, when possible, are an essential factor in the treatment of hemorrhagic events.

Percutaneous left atrial appendage closure: procedural techniques and outcomes

Percutaneous left atrial appendage closure technology for stroke prevention in patients with atrial fibrillation has significantly advanced in the past 2 decades. Several devices are under clinical investigation, and a few have already received Conformité Européene (CE)-mark approval and are available in many countries. The WATCHMAN device (Boston Scientific, Natick, Massachusetts) has the most supportive data and is under evaluation by the U.S. Food and Drug Administration for warfarin-eligible patients. The Amplatzer Cardiac Plug (St. Jude Medical, Plymouth, Minnesota) has a large real-world experience over the past 5 years, and a randomized trial comparing Amplatzer Cardiac Plug with the WATCHMAN device is anticipated in the near future. The Lariat procedure (SentreHEART Inc., Redwood City, California) has also gained interest lately, but early studies were concerning for high rates of serious pericardial effusion and major bleeding. The current real-world experience predominantly involves patients who are not long-term anticoagulation candidates or who are perceived to have high bleeding risks. This pattern of practice is expected to change when the U.S. Food and Drug Administration approves the WATCHMAN device for warfarin-eligible patients. This paper reviews in depth the procedural techniques, safety, and outcomes of the current leading devices.

Left atrial appendage exclusion for atrial fibrillation

Percutaneous left atrial appendage (LAA) closure is being increasingly used as a treatment strategy to prevent stroke in patients with atrial fibrillation (AF) who have contraindications to anticoagulants. Several approaches and devices have been developed in the last few years, each with their own unique set of advantages and disadvantages. In this article, the published studies on surgical and percutaneous approaches to LAA closure are reviewed, focusing on stroke mechanisms in AF, LAA structure and function relevant to stroke prevention, practical differences in procedural approach, and clinical considerations surrounding management.

Paradoxical cardiac and cerebral arterial gas embolus during percutaneous lead extraction in a patient with a patent foramen ovale

A 42 year-old man presented for elective percutaneous lead extraction for pacemaker redundancy. The procedure was performed supine under general anaesthesia via the right femoral vein and was complicated by acute inferior ST elevation and hypotension. Urgent transoesophageal echocardiogram showed inferior left ventricular hypokinesis, right ventricular impairment, a patent foramen ovale and air in the left ventricle. Coronary angiography demonstrated normal coronary arteries, the ST changes resolved and the leads were subsequently removed intact. Post-operatively the patient displayed nystagmus, was managed with hyperbaric oxygen therapy, and had complete resolution of his symptoms. An MRI brain confirmed an acute left cerebellar infarction, and a diagnosis of paradoxical air embolus to the coronary and cerebral circulations was made. This case illustrates the risks associated with paradoxical embolism in patients with PFOs undertaking percutaneous lead extractions. It also highlights the need for further consideration into techniques to avoid this complication in all high-risk percutaneous procedures.

Early safety and efficacy of percutaneous left atrial appendage suture ligation: results from the U.S. transcatheter LAA ligation consortium

BACKGROUND

Transcatheter left atrial appendage (LAA) ligation may represent an alternative to oral anticoagulation for stroke prevention in atrial fibrillation.

OBJECTIVES

This study sought to assess the early safety and efficacy of transcatheter ligation of the LAA for stroke prevention in atrial fibrillation.

METHODS

This was a retrospective, multicenter study of consecutive patients undergoing LAA ligation with the Lariat device at 8 U.S. sites. The primary endpoint was procedural success, defined as device success (suture deployment and <5 mm leak by post-procedure transesophageal echocardiography), and no major complication at discharge (death, myocardial infarction, stroke, Bleeding Academic Research Consortium bleeding type 3 or greater, or cardiac surgery). Post-discharge management was per operator discretion.

RESULTS

A total of 154 patients were enrolled. Median CHADS2 score (congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, prior stroke, transient ischemic attack, or thromboembolism [doubled]) was 3 (interquartile range: 2 to 4). Device success was 94%, and procedural success was 86%. A major complication occurred in 15 patients (9.7%). There were 14 major bleeds (9.1%), driven by the need for transfusion (4.5%). Significant pericardial effusion occurred in 16 patients (10.4%). Follow-up was available in 134 patients at a median of 112 days (interquartile range: 50 to 270 days): Death, myocardial infarction, or stroke occurred in 4 patients (2.9%). Among 63 patients with acute closure and transesophageal echocardiography follow-up, there were 3 thrombi (4.8%) and 13 (20%) with residual leak.

CONCLUSIONS

In this initial multicenter experience of LAA ligation with the Lariat device, the rate of acute closure was high, but procedural success was limited by bleeding. A prospective randomized trial is required to adequately define clinical efficacy, optimal post-procedure medical therapy, and the effect of operator experience on procedural safety.

Cardiac CT and echocardiographic evaluation of peri-device flow after percutaneous left atrial appendage closure using the AMPLATZER cardiac plug device

OBJECTIVES

The aim of the study was to examine frequency, size, and localization of peri-device leaks after percutaneous left atrial appendage (LAA)-closure with the AMPLATZER-Cardiac-Plug (ACP) by using a multimodal imaging approach, i.e. combined cardiac-CT and TEE follow-up.

BACKGROUND

Catheter-based LAA-occlusion using ACP aims to reduce the risk of stroke in patients with atrial fibrillation. Detection of peri-device leaks after ACP implantation by TEE is challenging, the few available data are inconsistent and the frequency of LAA leaks after ACP implantation remains therefore unclear.

METHODS

Cardiac-CT using a multi-phase protocol and a second-generation dual-source-CT-system was performed in 24 patients with non-valvular atrial fibrillation starting 3 months after LAA-closure by ACP. Color Doppler multiplane TEE was used to evaluate peri-device flow.

RESULTS

Cardiac-CT follow-up detected any persistent LAA contrast filling in 62% of patients (n = 15), but leak-sizes were small (1.5 ± 1.4 mm). Peri-device leaks were almost exclusively localized at the posterior portion of the LAA-orifice (>90%). TEE follow-up revealed peri-device flow in 36% of patients (jet-sizes: ≤ 4 mm). ACP-lobe compression (>10%) and perpendicular ACP-lobe orientation to the LAA-neck axis, that was also dependent on LAA anatomy, were substantially more frequent in patients with complete LAA closure.

CONCLUSION

The present study evaluates for the first time peri-device flow after LAA closure by ACP using a combined cardiac-CT and TEE follow-up. Persistent LAA-perfusion was frequently detected, leak-sizes were small and were less frequent when lobe compression was >10% and lobe orientation was perpendicular to the LAA-neck axis, that was also related to the LAA anatomy. The clinical significance of these small leaks after LAA-closure using ACP needs to be further evaluated in future studies.

Left atrial appendage closure using the Amulet device: an initial experience with the second generation amplatzer cardiac plug

OBJECTIVES

Aim of this study was to demonstrate the feasibility, safety, and short-term outcome of left atrial appendage (LAA) closure with a new generation LAA closure device.

BACKGROUND

The Amulet device (AGA, St Jude Medical, Minneapolis, MN) is a new generation of the amplatzer cardiac plug (ACP), specifically designed for LAA closure. This new version is designed to facilitate the implantation process and minimize procedural or device-related complications.

METHODS

The device was implanted in 17 patients with nonvalvular atrial fibrillation (AF). Clinical data were obtained at baseline, during the procedure, at discharge, at 30 and 90 days.

RESULTS

All devices were implanted successfully. Device sizes ranged from 20 mm to 31 mm. A 12 French (Fr) or 14 Fr delivery sheath was used depending on the selected device size. Full and partial recapture was performed in 1 case and 3 cases, respectively. There was 1 procedure-related pericardial effusion successfully managed with pericardiocentesis. There was no device embolization. The mean length of stay was 2.1 ± 0.3 days. At 90 days, there were no deaths, strokes, systemic thromboembolism, or bleeding complications. There was no device-related thrombus or pericardial effusion at 90-day TEE. In 2 of the 17 patients minimal peridevice flow (smaller than 2 mm) was present.

CONCLUSIONS

The Amulet device, which has new novel features as compared with the first generation ACP, is a feasible option for LAA closure. From our initial experience, implantation of the Amulet is associated with high success rate and good short-term outcome.

Prospective randomized evaluation of the Watchman Left Atrial Appendage Closure device in patients with atrial fibrillation versus long-term warfarin therapy: the PREVAIL trial

BACKGROUND

In the PROTECT AF (Watchman Left Atrial Appendage Closure Technology for Embolic Protection in Patients With Atrial Fibrillation) trial that evaluated patients with nonvalvular atrial fibrillation (NVAF), left atrial appendage (LAA) occlusion was noninferior to warfarin for stroke prevention, but a periprocedural safety hazard was identified.

OBJECTIVES

The goal of this study was to assess the safety and efficacy of LAA occlusion for stroke prevention in patients with NVAF compared with long-term warfarin therapy.

METHODS

This randomized trial further assessed the efficacy and safety of the Watchman device. Patients with NVAF who had a CHADS2 (congestive heart failure, hypertension, age >75 years, diabetes mellitus, and previous stroke/transient ischemic attack) score ≥2 or 1 and another risk factor were eligible. Patients were randomly assigned (in a 2:1 ratio) to undergo LAA occlusion and subsequent discontinuation of warfarin (intervention group, n = 269) or receive chronic warfarin therapy (control group, n = 138). Two efficacy and 1 safety coprimary endpoints were assessed.

RESULTS

At 18 months, the rate of the first coprimary efficacy endpoint (composite of stroke, systemic embolism [SE], and cardiovascular/unexplained death) was 0.064 in the device group versus 0.063 in the control group (rate ratio 1.07 [95% credible interval (CrI): 0.57 to 1.89]) and did not achieve the prespecified criteria noninferiority (upper boundary of 95% CrI ≥1.75). The rate for the second coprimary efficacy endpoint (stroke or SE >7 days' postrandomization) was 0.0253 versus 0.0200 (risk difference 0.0053 [95% CrI: -0.0190 to 0.0273]), achieving noninferiority. Early safety events occurred in 2.2% of the Watchman arm, significantly lower than in PROTECT AF, satisfying the pre-specified safety performance goal. Using a broader, more inclusive definition of adverse effects, these still were lower in PREVAIL (Watchman LAA Closure Device in Patients With Atrial Fibrillation Versus Long Term Warfarin Therapy) trial than in PROTECT AF (4.2% vs. 8.7%; p = 0.004). Pericardial effusions requiring surgical repair decreased from 1.6% to 0.4% (p = 0.027), and those requiring pericardiocentesis decreased from 2.9% to 1.5% (p = 0.36), although the number of events was small.

CONCLUSIONS

In this trial, LAA occlusion was noninferior to warfarin for ischemic stroke prevention or SE >7 days' post-procedure. Although noninferiority was not achieved for overall efficacy, event rates were low and numerically comparable in both arms. Procedural safety has significantly improved. This trial provides additional data that LAA occlusion is a reasonable alternative to warfarin therapy for stroke prevention in patients with NVAF who do not have an absolute contraindication to short-term warfarin therapy.

Experience of left atrial appendage closure performed under conscious sedation

Background

Percutaneous left atrial appendage closure is typically performed with transesophageal echocardiography guidance under general anesthesia. This study was performed to investigate the safety, feasibility, procedural characteristics, and outcomes of performing this procedure under conscious sedation without an anesthetist’s support.

Methods

Eleven patients (6 men; mean age 64.6 ± 10.4 years) with atrial fibrillation (median CHA2DS2VASc score 3) underwent transesophageal echocardiography-guided left atrial appendage occlusion under conscious sedation.

Results

All patients had successful procedures. Procedural duration and fluoroscopic times were 93.8 ± 25.3 and 16.2 ± 6.5 min, respectively. The doses of midazolam and fentanyl required were 5.4 ± 1.8 mg and 54.5 ± 27 µg, respectively. No complications arose from conscious sedation. Watchman (mean size 29 ± 5 mm) and Amplatzer Cardiac Plug (mean size 24 ± 4 mm) devices were implanted in 5 and 6 patients, respectively. One patient had device displacement due to over-compression on day one, and underwent successful percutaneous retrieval without any long-term sequelae. Warfarin was stopped in all patients after day 45, with transesophageal echocardiography showing optimal device position without a significant jet flow. In a mean follow-up of 12.1 ± 10.1 months, no thromboembolic complications were observed.

Conclusions

Percutaneous left atrial appendage occlusion can be performed safely and effectively under conscious sedation. This approach will significantly reduce the complexity and costs of this increasingly performed procedure.

Anatomical classification of left atrial appendages in specimens applicable to CT imaging techniques for implantation of amplatzer cardiac plug

BACKGROUND

Certain anatomical characteristics of the left atrial appendage (LAA) are associated with complexity in the implantation of occluder devices.

OBJECTIVE

The aim was to define characteristics measurable by three-dimensional imaging that would predict complexities both in the implantation procedure and the selection of the appropriate device size.

METHODS

An anatomical study was performed of 50 postmortem hearts, of which 15 had a history of atrial fibrillation, and of 30 consecutive patients undergoing LAA occlusion with the Amplatzer cardiac plug (ACP). The specimens were classified according to variables that can be visualized using computerized tomography (CT). The CT scans of 30 consecutive patients were classified according to the level of the LAA ostium, the left lateral ridge (LLR), the LAA limbus and distance from LAA to the mitral annulus before undergoing LAA occlusion, and the results were correlated.

RESULTS

Three types of LAA orifice were defined: type I, with a usually higher, anterior LAA ostium, a short, flattened and wide LLR and almost nonexistent limbus; type II, presenting a long, pointed and narrow LLR, and a longer, more defined limbus; type III, with a lower LAA ostium, close to the left atrium floor and the mitral annulus, a marked separation from the left pulmonary vein orifices and a limbus of intermediate length.

CONCLUSION

LAA with lower ostia are more difficult to occlude. Types II and III have very prominent LLRs with longer limbi, which may increase the difficulty of inserting the guide and making measurements for selection of the right ACP size.

Watchman Device: Left Atrial Appendage Closure For Stroke Prophylaxis In Atrial Fibrillation

A concerning proportion of patients with atrial fibrillation (AF) with indications for oral anticoagulation (OAC) discontinue OAC or are never prescribed OAC therapy and many AF patients with the highest risk for embolic events off OAC also have the greatest risk for hemorrhagic complications on OACs. Medium-term efficacy and safety data provide evidence that the WATCHMAN device, the most studied device and the only one with randomized and medium-term follow-up data, may be a viable alternative to chronic warfarin therapy in nonvalvular AF patients. In addition to presenting key data pertaining to LAA closure techniques including the WATCHMAN device, this review will discuss crucial WATCHMAN implantation technical points.

Left atrial appendage exclusion for prevention of stroke in atrial fibrillation: review of minimally invasive approaches

Stroke prevention is of vital importance in the management of atrial fibrillation (AF), though the proven strategy of systemic anticoagulation for thromboembolic prophylaxis is underutilized for a variety of reasons. The left atrial appendage (LAA) has long been suspected as the principal source of arterial emboli, particularly in nonvalvular AF, and a variety of techniques for its exclusion from the circulation have been developed. This review highlights the history of the LAA as a target of intervention, and the parallel advances in three minimally invasive strategies for its exclusion: percutaneous occlusion of the LAA orifice from within the left atrium, closed-chest ligation via a percutaneous pericardial approach, and minimally invasive thoracoscopic surgery. While further study is necessary, available evidence suggests that effective LAA exclusion is becoming a viable alternative to anticoagulation for stroke prevention in nonvalvular AF.

Filling the gap: interventional occlusion of incompletely ligated left atrial appendages

AIMS

Patients undergoing heart surgery and with history of atrial fibrillation are often treated with intraoperative left atrial appendage (LAA) ligation. Incomplete LAA ligation is often described and can be associated with thrombo-embolic complications. To describe a case series of percutaneous LAA occlusion in patients previously treated with surgical LAA ligation.

METHODS AND RESULTS

Over 179 patients treated with implantation of an LAA-occluder system at our centre, 3 (1.6%) were previously treated with a surgical LAA suture exclusion (2 males, age 74 ± 3 years). Patients 1 and 3 presented a 'hammerhead' LAA morphology with an open neck and were successfully treated with an AGA Cardiac Plug (ACP-St Jude Medical) Device. Patient 2 had a conic monolobar LAA with a small neck, and the occlusion could be performed using a Watchman (Boston Scientific) device. After discharge on dual antiplatelet therapy, all the patients could be switched to single aspirin (ASA) therapy after a 6-week transoesophageal echocardiography control.

CONCLUSION

Left atrial appendage occlusion in patient with incomplete surgical ligation using percutaneous LAA occluder devices appears to be feasible, and studies including a larger number of patients are needed.

Mechanical closure devices for atrial fibrillation

Atrial fibrillation (AF) is the most commonly sustained arrhythmia and is a major cause of stroke and systemic embolism. Chronic oral anticoagulation reduces this risk, but at the cost of increased bleeding. In addition, a substantial proportion of AF patients who are at moderate-to-high risk for stroke are undertreated due to real or perceived contraindications. The major source of thromboembolism in AF appears to be the left atrial appendage (LAA). Therefore, device closure of the LAA represents a mechanical approach to stroke prevention in AF patients. In this review, we describe the rationale for device closure of the LAA, summarize the current dataset for LAA closure devices, and set forth a framework to help guide patient selection for device therapy.

Surgical left atrial appendage occlusion during cardiac surgery for patients with atrial fibrillation: a meta-analysis

OBJECTIVES

Concomitant left atrial appendage occlusion (LAAO) during surgical ablation has emerged as a potential treatment strategy to reduce stroke and perioperative mortality in patients with atrial fibrillation (AF). The present meta-analysis aims to assess current evidence on the efficacy and safety between LAAO and LAA preservation cohorts for patients undergoing cardiac surgery.

METHODS

Electronic searches were performed using six electronic databases from their inception to November 2013, identifying all relevant comparative randomized and observational studies comparing LAAO with non-LAAO in AF patients undergoing cardiac surgery. Data were extracted and analysed according to predefined endpoints including mortality, stroke, postoperative AF and reoperation for bleeding.

RESULTS

Seven relevant studies identified for qualitative and quantitative analyses, including 3653 patients undergoing LAAO (n = 1716) versus non-LAAO (n = 1937). Stroke incidence was significantly reduced in the LAAO occlusion group at the 30-day follow-up [0.95 vs 1.9%; odds ratio (OR) 0.46; P = 0.005] and the latest follow-up (1.4 vs 4.1%; OR 0.48; P = 0.01), compared with the non-LAAO group. Incidence of all-cause mortality was significantly decreased with LAAO (1.9 vs 5%; OR 0.38; P = 0.0003), while postoperative AF and reoperation for bleeding was comparable.

CONCLUSIONS

While acknowledging the limitations and inadequate statistical power of the available evidence, this study suggests LAAO as a promising strategy for stroke reduction perioperatively and at the short-term follow-up without a significant increase in complications. Larger randomized studies in the future are required, with clearer surgical and anticoagulation protocols and adequate long-term follow-up, to validate the clinical efficacy of LAAO versus non-LAAO groups.

Latest advances in transseptal structural heart interventions-Percutaneous Mitral Valve Repair and Left Atrial Appendage Occlusion

Recent advances in structural heart intervention have produced increasing demand for transseptal access, which was first introduced as a diagnostic tool to directly measure left atrial pressure. Transseptal access allows safe and adequate approach to the left atrium and surrounding structures. Percutaneous transcatheter mitral valve repair using the MitraClip device is a safe and less invasive treatment for selected patients with significant mitral regurgitation, who are at high risk for surgery. This is an echocardiographic- and fluoroscopic-guided procedure requiring accurate transseptal access of the left atrium and clipping of the mitral leaflets at the precise location of their malcoaptation. Percutaneous transcatheter closure of the left atrial appendage is another novel procedure that requires transseptal access of the left atrium, followed by closure or ligation of the left atrial appendage. This catheter-based therapy has been shown to be a safe and effective alternative to long-term anticoagulant therapy for the prevention of stroke in patients with atrial fibrillation. In this article, we systematically review these novel structural heart interventions.

Left atrial appendage closure in patients with atrial fibrillation in whom warfarin is contra-indicated: initial South African experience

Atrial fibrillation is a common cause of cardiac embolic events, especially stroke. Oral anticoagulation therapy is used to reduce these events. Many patients however are unable to take such therapy. Percutaneous occlusion of the left atrial appendage (the source of 90% of these emboli) is an option in these patients. Presented here are the first 12 patients to have this procedure done in South Africa.

Preserving Cognitive Function in Patients with Atrial Fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide and is associated with significant morbidity and mortality. Its prevalence increases with increasing age, and is one of the leading causes of thromboembolism, including ischemic stroke. The prevalence of cognitive dysfunction also increases with increasing age. Although several studies have shown a strong correlation between AF and cognitive dysfunction in patients with and without overt stroke, a direct causative link has yet to be established. Rhythm vs rate control and anticoagulation regimens have been extensively investigated, particularly with the introduction of the novel anticoagulants. With catheter ablation becoming more prevalent for the management of AF and the ongoing development of various new energy sources and catheters, an additional thromboembolism risk is introduced. As cognitive dysfunction decreases the patient's ability to self-care and manage a complex disease such as AF, this increases the burden to our healthcare system. Therefore as the prevalence of AF increases in the general population, it becomes more imperative that we strive to optimize our methods to preserve cognitive function. This review gives an overview of the current evidence behind the association of AF with cognitive dysfunction, and discusses the most up-to-date medical and procedural treatment strategies available for decreasing thromboembolism associated with AF and its treatment, which may lead to preserving cognitive function.

Complications From Left Atrial Appendage Exclusion Devices

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and has been identified as an independent risk factor for stroke. Prevention of thromboembolic events has been based on oral anticoagulation (OAC) using Vitamin K antagonists (VKA). However, long-term OAC medication is limited by an increased bleeding risk and a low patient compliance. Relying on the observation that the majority of cardiac thrombi originate from the left atrial appendage (LAA) different devices aiming for LAA closure have been proposed. This review will discuss contemporary LAA closure devices with special emphasis on procedure related complications.

Left atrial appendage closure devices

Atrial fibrillation (AF) increases the risk for thromboembolic stroke five-fold. The left atrial appendage (LAA) has been shown to be the main source of thrombus formation in the majority of strokes associated with AF. Oral anticoagulation with warfarin and novel anticoagulants remains the standard of care; however, it has several limitations, including bleeding and poor compliance. Occlusion of the LAA has been shown to be an alternative therapeutic approach to drug therapy. The purpose of this article is to review the different techniques and devices that have emerged for the purpose of occluding this structure, with a particular emphasis on the efficacy and safety studies published to date in the medical literature.

Percutaneous left atrial appendage occlusion for stroke prevention in atrial fibrillation: an update

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia encountered in clinical practice. One of its most devastating complications is the development of thromboembolism leading to fatal or disabling stroke. Oral anticoagulation (OAC, warfarin) is the standard treatment for stroke prevention in patients with AF with an increased stroke risk. However, there are several obstacles to long-term OAC therapy, including the risk of serious bleeding, several drug–drug interactions and the need for frequent blood testing. Although newer oral anticoagulants have been developed, these drugs also face issues of major bleeding and non-compliance. Therefore, alternative treatment options for stroke prevention in patients with AF with a high stroke risk are needed. Percutaneous left atrial appendage (LAA) occlusion is an evolving therapy, which should be taken into consideration in those patients with non-valvular AF with a high stroke risk and contraindications for OAC. This article aims to discuss the rationale for LAA closure, the available LAA occlusion devices and their clinical evidence until now. Moreover, we discuss the importance of proper patient selection, the role of various imaging techniques and the need for a more tailored postprocedural antithrombotic therapy.

Left Atrial Appendage Closure Devices For Stroke Prevention

Cardioembolic stroke is a major cause of morbidity and mortality in patients with atrial fibrillation (AF). The left atrial appendage (LAA) is the prominent source of clot formation. While systemic anticoagulation is the current standard of care, anticoagulants carry many contraindications and possible complications. Techniques for elimination of the LAA are in various stages of development and early clinical use. In the coming years, accumulating data will help guide the management of AF patients at risk of bleeding as well as potentially become first-line therapy to reduce the risk of thromboembolic stroke. The purpose of this article is to review current endovascular and epicardial catheter-based LAA occlusion devices and the clinical data supporting their use.

Anticoagulation in atrial fibrillation

Atrial fibrillation increases the risk of stroke, which is a leading cause of death and disability worldwide. The use of oral anticoagulation in patients with atrial fibrillation at moderate or high risk of stroke, estimated by established criteria, improves outcomes. However, to ensure that the benefits exceed the risks of bleeding, appropriate patient selection is essential. Vitamin K antagonism has been the mainstay of treatment; however, newer drugs with novel mechanisms are also available. These novel oral anticoagulants (direct thrombin inhibitors and factor Xa inhibitors) obviate many of warfarin's shortcomings, and they have demonstrated safety and efficacy in large randomized trials of patients with non-valvular atrial fibrillation. However, the management of patients taking warfarin or novel agents remains a clinical challenge. There are several important considerations when selecting anticoagulant therapy for patients with atrial fibrillation. This review will discuss the rationale for anticoagulation in patients with atrial fibrillation; risk stratification for treatment; available agents; the appropriate implementation of these agents; and additional, specific clinical considerations for treatment.

Clinical Results with Percutaneous Left Atrial Appendage Occlusion

Closure of the left atrial appendage (LAA) in patients with non-valvular atrial fibrillation is associated with reduction in embolic events. There is an initial hazard associated with closure methodologies; once successful closure is achieved, the results appear to be superior to those of anticoagulation. The evidence base is largely limited to the safety and efficacy of LAA occlusion in patients who are candidates for anticoagulation as well, and the risk/benefit ratio of competing closure technologies has not been determined. LAA occlusion plus antiplatelet therapy seems to have an acceptable therapeutic and safety profile.

Prevention and Management of Complications of Left Atrial Appendage Closure Devices

Atrial fibrillation is associated with an ongoing risk of thromboembolic stroke and systemic embolism due to stasis and thrombus formation within the left atrial appendage (LAA). Transcatheter occlusion or ligation of the LAA represents a potential paradigm shift in the management of stroke prevention in at-risk patients with atrial fibrillation. This review summarizes the types and rates of procedural complications that have been observed with LAA occlusion and ligation; describes strategies that can be implemented to minimize these complications; and discusses management approaches that may limit the impact of these complications on long-term morbidity.