Over 1-year efficacy and safety of left atrial appendage occlusion versus novel oral anticoagulants for stroke prevention in atrial fibrillation: A systematic review and meta-analysis of randomized controlled trials and observational studies

Clinical Outcomes of Left Atrial Appendage Occlusion Versus Switch of Direct Oral Antcoagulant in Atrial Fibrillation: A Territory-Wide Retrospective Analysis

Background Left atrial appendage occlusion (LAAO) has emerged as an alternative to oral anticoagulation therapy for stroke prevention in atrial fibrillation, but data comparing LAAO with direct oral anticoagulant (DOAC) are sparse. Methods and Results This cohort study compared LAAO (with or without prior anticoagulation) with a switch of one DOAC to another DOAC by 1:2 propensity score matching. The primary outcome was a composite of all-cause mortality, ischemic stroke, and major bleeding. A total of 2350 patients (874 in the LAAO group and 1476 in the DOAC switch group) were included. After a mean follow-up of 1052±694 days, the primary outcome developed in 215 (24.6%) patients in the LAAO group and in 335 (22.7%) patients in the DOAC switch group (hazard ratio [HR], 0.94 [95% CI, 0.80-1.12]; P=0.516). The LAAO group had a lower all-cause mortality (HR, 0.49 [95% CI, 0.39-0.60]; P<0.001) and cardiovascular mortality (HR, 0.49 [95% CI, 0.32-0.73]; P<0.001) but similar risk of ischemic stroke (HR, 0.83 [95% CI, 0.63-1.10]; P=0.194). The major bleeding risk was similar overall (HR, 1.18 [95% CI, 0.94-1.48], P=0.150) but was lower in the LAAO group after 6 months (HR, 0.71 [95% CI, 0.51-0.97]; P=0.032). Conclusions LAAO conferred a similar risk of composite outcome of all-cause mortality, ischemic stroke, and major bleeding, as compared with DOAC switch. The risks of all-cause mortality and cardiovascular mortality were lower with LAAO.

Left Atrial Appendage Occlusion-A Choice or a Last Resort? How to Approach the Patient

Left atrial appendage (LAA) occlusion is emerging as a viable alternative to oral anticoagulation in high-risk patients with atrial fibrillation. However, there remains limited evidence for this approach, especially in certain subgroups, and therefore patient selection is an important aspect of treatment. Here, the authors present arguments for LAA occlusion as either a last resort versus patient choice by evaluating contemporary studies on this topic and discuss practical steps in the approach of patients who may be suitable for LAA occlusion. Overall, an individualized and multidisciplinary team approach should be adopted in patients who are being considered for LAA occlusion.

Sex Differences in Periprocedural and Long-Term Outcomes Following Transcatheter Left Atrial Appendage Occlusion: A Systematic Review and Meta-Analysis

BACKGROUND

Atrial fibrillation (AF) is among the most common arrhythmias associated with an increased risk of cardioembolic phenomena, including stroke. Percutaneous left atrial appendage occlusion (LAAO) has proven beneficial in reducing stroke and mortality in patients with atrial fibrillation who have contraindications to anticoagulation. However, the sex differences in outcomes following LAAO have not been studied systematically.

METHODS

Electronic databases PUBMED, Embase, and Web of Science were systematically searched until March 2022 for studies evaluating patient outcomes following LAAO for AF. The primary outcomes of interest were the risks of periprocedural stroke, major bleeding, pericardial complications, and all-cause mortality. Secondary outcomes included stroke risks, major bleeding, device-related thrombus, cardiovascular and all-cause mortality on long-term follow-up. A random-effects model meta-analysis was conducted, and heterogeneity was assessed using the I-squared test.

RESULTS

Sixteen studies were included in the final analysis encompassing 111,775 patients, out of which 45,441 (40.7 %) were women. Women had a significantly higher risk of peri-procedural complications including all-cause mortality [relative risk (RR), 95 % confidence intervals (CI); RR 1.94, 95 % CI 1.40-2.69], stroke [RR 1.85, 95 % CI 1.29-2.67], major bleeding [RR 1.63, 95 % CI 1.08-2.44], and pericardial events [RR 1.80, 95 % CI 1.58-2.05]. However, there were no statistically significant differences between sexes in terms of risk of stroke, major bleeding, device-related thrombus, cardiovascular and all-cause mortality on long-term follow-up.

CONCLUSION

Among patients undergoing LAAO implantation, women were at higher risk of periprocedural complications than men. This risk was not significant on long-term follow-up.

Heart Team for Left Appendage Occlusion without the Use of Antithrombotic Therapy: The Epicardial Perspective

BACKGROUND

Left atrial appendage occlusion is an increasingly proposed treatment for patients with atrial fibrillation and poor tolerance to anticoagulants. All endovascular devices require antithrombotic therapy. Anatomical and clinical variables predisposing to device-related thrombosis, as well as post-procedural peri-device leaks, could mandate the continuation or reintroduction of aggressive antithrombotic treatment. Because of the absence of foreign material inside the heart, epicardial appendage closure possibly does not necessitate antithrombotic therapy, but data of large series are missing.

METHODS

Multidisciplinary team evaluation for standalone totally thoracoscopic epicardial appendage closure was done in 180 consecutive patients with atrial fibrillation and poor tolerance to antithrombotic therapy. One hundred and fifty-two patients consented (male 66.1%, mean age 76.1 ± 7.4, CHA2DS2VASc mean 5.3 ± 1.6, HASBLED mean 3.8 ± 1.1). Indications were cerebral hemorrhage (48%), gastro-intestinal bleeding (33.3%), and other bleeding (20.7%). No antithrombotic therapy was prescribed from the day of surgery to the latest follow up.

RESULTS

Procedural success was 98.7%. At a mean follow up of 38.2 ± 18.8 months, cardioembolic and bleeding events were 1.3% and 0.6%, respectively. Among patients with a history of blood transfusions (41.1%), none needed further transfusions or treatment post procedure.

CONCLUSION

Epicardial appendage occlusion without any antithrombotic therapy appears to be safe and effective. This strategy could be advised when minimization of bleeding risk concomitant to stroke prevention is needed.

Outcomes of cardiac surgery with left atrial appendage occlusion versus no Occlusion, direct oral Anticoagulants, and vitamin K Antagonists: A systematic review with Meta-analysis

Surgical left atrial appendage occlusion (LAAO) is being used increasingly in the setting of atrial fibrillation but has been associated with procedural complications. This systematic review and meta-analysis compared the outcomes of surgical LAAO with those of no LAAO and the use of direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs) using the PRISMA guidelines. A literature search was undertaken for relevant studies published between January 1, 2003, and August 15, 2021. Primary clinical outcomes were all-cause mortality, embolic events, and stroke. Secondary clinical outcomes included major adverse cardiac events (MACE), postoperative atrial fibrillation, postoperative complications, reoperation for bleeding, and major bleeding. There was a statistically significant 34% reduction in incidence of embolic events (odds ratio [OR] 0.66, 95% confidence interval [CI] 0.57–0.77, p < 0.001) and a significant 42% reduction in risk of MACE (OR 0.58, 95% CI 0.38–0.88, p = 0.01) in patients who underwent LAAO.Surgical LAAO has the potential to reduce embolic events and MACE in patients undergoing cardiac surgery for atrial fibrillation. However, complete replacement of DOACs and warfarin therapy with surgical LAAO is unlikely despite its non-inferiority in terms of minimizing all-cause mortality, embolic events, MACE, major bleeding, and stroke in patients on oral anticoagulation therapies.

Rehearsal simulation to determine the size of device for left atrial appendage occlusion using patient-specific 3D-printed phantoms

Left atrial appendage (LAA) occlusion (LAAO) is used to close the finger-like extension from the left atrium with occlusion devices to block the source of thrombosis. However, selection of the devices size is not easy due to various anatomical changes. The purpose of this study is patient-specific, computed tomography angiography (CTA)-based, three-dimensionally (3D) printed LAAO phantoms were applied pre-procedure to determine the size. Ten patients were enrolled prospectively in March 2019 and December 2020. The cardiac structure appearing in CTA was first segmented, and the left atrium and related structures in the LAAO procedure were modeled. The phantoms were fabricated using two methods of fused deposition modeling (FDM) and stereolithography (SLA) 3D printers with thermoplastic polyurethane (TPU) and flexible resin materials and evaluated by comparing their physical and material properties. The 3D-printed phantoms were directly used to confirm the shape of LAA, and to predict the device size for LAAO. In summary, the shore A hardness of TPU of FDM was about 80–85 shore A, and that of flexible resin of SLA was about 50–70 shore A. The measurement error between the STL model and 3D printing phantoms were 0.45 ± 0.37 mm (Bland–Altman, limits of agreement from − 1.8 to 1.6 mm). At the rehearsal, the estimations of device sizes were the exact same with those in the actual procedures of all 10 patients. In conclusion, simulation with a 3D-printed left atrium phantom could be used to predict the LAAO insertion device size accurately before the procedure.

Left Atrial Appendage Occlusion-A Choice or a Last Resort? How to Approach the Patient

Left atrial appendage (LAA) occlusion is emerging as a viable alternative to oral anticoagulation in high-risk patients with atrial fibrillation. However, there remains limited evidence for this approach, especially in certain subgroups, and therefore patient selection is an important aspect of treatment. Here, the authors present arguments for LAA occlusion as either a last resort versus patient choice by evaluating contemporary studies on this topic and discuss practical steps in the approach of patients who may be suitable for LAA occlusion. Overall, an individualized and multidisciplinary team approach should be adopted in patients who are being considered for LAA occlusion.

2019 Chinese expert consensus statement on left atrial appendage closure in patients with atrial fibrillation

The left atrial appendage closure (LAAC), the efficacy and safety of which has been proved by a number of randomized controlled trials and registries, is recommended by several guidelines to prevent stroke in high‐risk patients with non‐valvular atrial fibrillation. However, current guidelines only discuss the indications and contraindications of LAAC, as an emerging technology, there still lacks comprehensive recommendations involved with LAAC, including devices, image assessment modality, identification and treatment of complications, perioperative medication, and postoperative management. Therefore, the Chinese Society of Cardiology (CSC) of Chinese Medical Association (CMA) and the Editorial Board of Chinese Journal of Cardiology jointly issued the expert consensus statement on LAAC in the prevention of stroke in patients with atrial fibrillation after comprehensive discussion by experts with different backgrounds. This consensus provided three levels of recommendations to guide and standardize the clinical application of LAAC based on existing evidence and clinical practice experience, including appropriate (more potential benefits or fewer harms), uncertain (somehow reasonable but need more evidence), and inappropriate (unlikely to benefit, or have more complications).

Latest outcomes of transcatheter left atrial appendage closure devices and direct oral anticoagulant therapy in patients with atrial fibrillation over the past 5 years: a systematic review and meta-analysis

Left atrial appendage closure (LAAC) are emerging treatment for patients with atrial fibrillation (AF). However, data on the safety, efficacy, and medications for LAAC devices in patients with AF are lacking. We aimed to investigate the incidence of all-cause mortality, stroke, and major bleeding in AF patients with LAAC devices and DOACs. Moreover, we aimed to investigate the incidence rate of device-related thrombus (DRT) and the medications used in the management of AF patients with LAAC devices to gain insights into achieving better outcome. Based on a literature search using PubMed, EMBASE, Cochrane Library, and Web of Science databases between January 2015 and December 2020, eight LAAC device studies that used WATCHMAN and Amulet, and three DOAC studies that used rivaroxaban, with a total of 24,055 AF patients (LAAC devices, n = 2855; DOAC, n = 21,200), were included. A random-effects model was used to incorporate heterogeneity among studies. The pooled incidence of events per person-years were as follows: all-cause mortality, 0.06 (95% confidence interval [CI] 0.02-0.10) for WATCHMAN, 0.04 (95% CI 0.00-0.14) for Amulet, and 0.03 (95% CI 0.01-0.04) for rivaroxaban; stroke; 0.02 (95% CI 0.00-0.04) for WATCHMAN, 0 for Amulet, and 0.01 (95% CI 0.01-0.02) for rivaroxaban; major bleeding, 0.04 (95% CI 0.02-0.06) for WATCHMAN, 0.02 (95% CI 0.00-0.06) for Amulet, and 0.02 (95% CI 0.01-0.03) for rivaroxaban. The incidence rate of DRT was 2.3%, and complications were reported in 9%. The incidence of all-cause mortality, stroke, and major bleeding were similar between LAAC devices and DOACs. The rate of complications was acceptable, and those of DRT were lower than the average incidence reported in previous studies. However, further follow-up is needed. Concomitant anticoagulant and antiplatelet therapies should be further evaluated to find the optimal regimen for AF patients with LAAC devices.

Clinical Outcomes Associated With Left Atrial Appendage Occlusion Versus Direct Oral Anticoagulation in Atrial Fibrillation

OBJECTIVES

This study sought to investigate clinical outcomes associated with left atrial appendage occlusion (LAAO) versus direct oral anticoagulants (DOACs) in patients with high-risk atrial fibrillation (AF).

BACKGROUND

LAAO has been shown to be noninferior to warfarin for stroke prevention in AF. However, anticoagulation with DOACs is now preferred over warfarin as thromboprophylaxis in AF.

METHODS

Patients with AF enrolled in the Amulet Observational Registry (n = 1,088) who had successful LAAO with the Amplatzer Amulet device (n = 1,078) were compared with a propensity score-matched control cohort of incident AF patients (n = 1,184) treated by DOACs identified from Danish national patient registries. Propensity score matching was based on the covariates of the CHA₂DS₂-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism, vascular disease, age 65-74 years, sex category) and HAS-BLED (hypertension, abnormal renal or liver function, stroke, bleeding, labile international normalized ratio, elderly, drugs or alcohol) scores for predicting stroke and bleeding. The primary outcome was a composite of ischemic stroke, major bleeding (Bleeding Academic Research Consortium ≥3), or all-cause mortality, and follow-up was 2 years.

RESULTS

AF patients treated with LAAO had a significantly lower risk of the primary composite outcome as compared with patients treated with DOACs (hazard ratio [HR]: 0.57; 95% confidence interval [CI]: 0.49 to 0.67). Total events and event rates per 100 patient-years were (LAAO vs. DOACs) 256 vs. 461 and 14.5 vs. 25.7, respectively. The risk of ischemic stroke was comparable between groups (HR: 1.11; 95% CI: 0.71 to 1.75), while risk of major bleeding (HR: 0.62; 95% CI: 0.49 to 0.79) and all-cause mortality (HR: 0.53; 95% CI: 0.43 to 0.64) were significantly lower in patients treated with LAAO.

CONCLUSIONS

Among high-risk AF patients, LAAO in comparison with DOACs may have similar stroke prevention efficacy but lower risk of major bleeding and mortality.

Percutaneous Left Atrial Appendage Occlusion: An Emerging Option in Patients with Atrial Fibrillation at High Risk of Bleeding

Atrial fibrillation (AF) is a common cardiac arrhythmia with an estimated prevalence of 1% in the general population. It is associated with an increased risk of ischemic stroke, silent cerebral ischemia, and cognitive impairment. Due to the blood flow stasis and morphology, thrombus formation occurs mainly in the left atrial appendage (LAA), particularly in the setting of nonvalvular AF (NVAF). Previous studies have shown that >90% of emboli related to NVAF originate from the LAA, thus prevention of systemic cardioembolism is indicated. According to the current guidelines, anticoagulant therapy with direct oral anticoagulants (DOACs) or vitamin K antagonists (VKAs), represents the standard of care in AF patients, in order to prevent ischemic stroke and peripheral embolization. Although these drugs are widely used and DOACs have shown, compared to VKAs, non-inferiority for stroke prevention with significantly fewer bleeding complications, some issues remain a matter of debate, including contraindications, side effects, and adherence. An increasing number of patients, indeed, because of high bleeding risk or after experiencing life-threatening bleedings, must take anticoagulants with extreme caution if not contraindicated. While surgical closure or exclusion of LAA has been historically used in patients with AF with contradictory results, in the recent years, a novel procedure has emerged to prevent the cardioembolic stroke in these patients: The percutaneous left atrial appendage occlusion (LAAO). Different devices have been developed in recent years, though not all of them are approved in Europe and some are still under clinical investigation. Currently available devices have shown a significant decrease in bleeding risk while maintaining efficacy in preventing thromboembolism. The procedure can be performed percutaneously through the femoral vein access, under general anesthesia. A transseptal puncture is required to access left atrium and is guided by transesophageal echocardiography (TEE). Evidence from the current literature indicates that percutaneous LAAO represents a safe alternative for those patients with contraindications for long-term oral anticoagulation. This review summarizes scientific evidences regarding LAAO for stroke prevention including clinical indications and an adequate patient selection.

Percutaneous left atrial appendage occlusion for stroke prevention in patients with atrial fibrillation

Patients with atrial fibrillation (AF) have a fivefold higher risk of stroke than persons in sinus rhythm. Effective stroke prevention is achieved with oral anticoagulants such as vitamin K antagonists or nonvitamin K oral anticoagulants. An alternative for stroke prevention in patients with AF is the closure of the left atrial appendage (LAA) with a percutaneously applied closure system. The two large randomized studies PROTECT-AF and PREVAIL failed to show superiority of LAA closure over anticoagulation in patients with AF. Meta-analyses of studies and registries, however, suggest that LAA closure has particular advantages with regard to the reduction of severe bleeding complications. Currently, several prospective randomized studies are being conducted in different patient populations to evaluate the benefit of LAA closure in comparison to standard of care. Currently, LAA closure is recommended in patients after intracranial hemorrhage, with advanced renal failure, after severe gastrointestinal bleeding, in patients with a high risk of recurrent ischemic stroke and elderly patients with high risk of bleeding and falling.

Left Atrial Appendage Occlusion in the Management of Stroke in Patients With Atrial Fibrillation

Atrial fibrillation (AF) is associated with a substantially higher risk of thromboembolism, particularly stroke events, resulting in significant morbidity and mortality. Oral anticoagulation (OAC), while effective in reducing embolic events in AF patients, is associated with an increased bleeding risk. Thus, not all patients with AF are candidates for OAC and some are only candidates for OAC in the short term. Of the available nonpharmacologic strategies for the management of AF, left atrial appendage occlusion (LAAO) has emerged as a potential approach for reducing the risk of systemic thromboembolism in AF patients eligible for OAC. LAAO can be achieved either surgically or percutaneously using an epicardial, endocardial, or a combined approach. Although available data are limited, currently available LAAO devices, and those being developed, have shown promise in reducing bleeding risk in AF patients because of the reduced overall need for anticoagulation, while maintaining efficacy in preventing thromboembolism. The optimal device will reduce both embolic and hemorrhagic strokes, and other bleeds, with a high implant success rate and a low complication rate. Until that time, anticoagulation remains the gold standard that these devices strive to surpass, and thus LAAO devices are currently indicated in patients with relative contraindication to OAC therapy.

[Recent and upcoming randomized trials for left atrial appendage occlusion : Need for a definite assessment of the situation]

Atrial fibrillation (AF) is the most common arrhythmia affecting more than 1.6 million patients in Germany. Based on demographic developments, an the number is expected to increase. Embolic strokes in AF patients are particularly severe, and individualized new oral anticoagulant (NOAC) therapy reduces the incidence of stroke in these patients by approximately 70%. Besides vitamin K antagonists, the NOACs rivaroxaban, dabigatran, apixaban, and edoxaban have been introduced into clinical practice; however, major bleeding still occurs at a rate of 2-3% per year. Moreover, randomized studies and real-life registries suggest that >20% of patients with AF and an indication for anticoagulation cannot tolerate chronic oral anticoagulant therapy. Therefore, an alternative method for stroke prevention in AF patients has been developed, i. e., catheter-based exclusion of the left atrial appendage (LAA), a location that is prone for thrombus formation in these patients. The randomized trials of catheter-based LAA occlusion have compared this interventional therapy with vitamin K antagonists. In the future, however, LAA exclusion needs to be compared with NOAC therapy. Moreover, percutaneous LAA exclusion in clinical practice is mostly offered to patients ineligible for long-term oral anticoagulation or with high bleeding risk. However, no controlled, randomized trial data exist for this patient population. These data are needed for appropriate clinical judgment and optimal clinical management. Ongoing studies and scientific questions that are important to define the future for catheter-based LAA closure are discussed in this review.

Left atrial appendage closure in patients with intracranial haemorrhage and atrial fibrillation

INTRODUCTION

The use of oral anticoagulants in patients with a history of atrial fibrillation (AF) and intracranial haemorrhage (ICH) is controversial on account of the risk of haemorrhagic stroke recurrence. This study presents our experience regarding the safety and efficacy of percutaneous left atrial appendage closure (LAAC), an alternative to anticoagulation in these patients.

METHODS

We conducted a retrospective, single-centre, observational study. LAAC was performed in patients with a history of ICH and non-valvular AF. Risk of ischaemic and haemorrhagic events was estimated using the CHA2DS2-VASc and HAS-BLED scales. We recorded periprocedural complications, IHC recurrence, cerebral/systemic embolism, mortality and use of antithrombotic drugs following the procedure.

RESULTS

LAAC was performed in 9 patients (7 men, 2 women) using the AMPLATZER Amulet device in 7 cases and the AMPLATZER Cardiac Plug device in 2. Mean age was 72.7±8.2 years. Time between ICH and LAAC was less than one month in 5 patients and more than one month in 4 patients. Median CHA2DS2-VASc score was 4 (interquartile range of 2.5). Median HAS-BLED score was 3 (interquartile range of 0). No periprocedural complications were recorded. All patients received single anti-platelet therapy (clopidogrel in 5 patients, aspirin in 4) after the procedure; 5 patients received this treatment for 6 months and 4 received it indefinitely. No ischaemic or haemorrhagic events were recorded during follow-up (mean duration of 15 months).

CONCLUSIONS

In our series, LAAC was found to be safe and effective in patients with a history of ICH who required anticoagulation due to AF.

Managing the Left Atrial Appendage in Atrial Fibrillation: Current State of the Art

BACKGROUND

Patients with atrial fibrillation are at increased risk for thromboembolic stroke originating predominantly in the left atrial appendage. To reduce the risk, the standard of care is anticoagulation. In addition, several devices for exclusion of the left atrial appendage have been developed.

METHODS

PubMed was searched for articles relevant to left atrial appendage management. The resulting articles were reviewed as were relevant articles in their bibliographies. Relevant journals were manually searched for sources.

RESULTS

Devices are being used for left atrial appendage exclusion by percutaneous and surgical approaches. Their indications, limitations, and outcomes are reviewed.

CONCLUSIONS

Excision and exclusion of the left atrial appendage is safe and as effective as medical management of atrial fibrillation for stroke prevention. The choice of treatment should be made based on patients' anatomy, history, and preference informed by an appropriate left atrial appendage management team.