Device-Related Thrombus After Left Atrial Appendage Closure: Incidence, Predictors, and Outcomes

Left atrial appendage occlusion in atrial fibrillation: shaping the future of stroke prevention

Atrial fibrillation (AF) is the most common cardiac arrhythmia, significantly increasing the risk of thromboembolic events, particularly ischemic stroke. The left atrial appendage (LAA) is the predominant site of thrombus formation in patients with AF, making it a crucial target for stroke prevention strategies. Left atrial appendage occlusion (LAAO) has emerged as an important therapeutic alternative to oral anticoagulation, particularly in patients with contraindications to long-term anticoagulant therapy. This review examines the role of LAAO in AF management, discussing current indications, patient selection, procedural techniques, and clinical outcomes. We also explore the latest evidence from major clinical trials and real-world studies, highlighting the efficacy and safety of LAAO compared to standard anticoagulation. Additionally, we consider the unresolved questions and the potential future directions for this intervention, including emerging technologies and the integration of LAAO into broader AF management protocols. Our review underscores the growing importance of LAAO in reducing thromboembolic risk in AF patients, particularly those unable to tolerate traditional anticoagulation, and offers insights into the ongoing evolution of this treatment modality in clinical practice.

Association Between Triglyceride-Glucose Index and Incomplete Device Endothelialization After Left Atrial Appendage Occlusion: A Retrospective Observational Study

BACKGROUND

The triglyceride-glucose (TyG) index, a biomarker for insulin resistance, has been shown to be associated with cardiovascular diseases. However, its association with delayed device endothelialization after left atrial appendage occlusion (LAAO) has not yet been explored.

METHODS

This retrospective study included 594 patients with non-valvular atrial fibrillation (NVAF) who underwent LAAO with the Watchman2.5 device at the Electrophysiology Center of Taizhou People's Hospital, Nanjing Medical University. Postoperative follow-up was performed at 3 months using Contrast-Enhanced Computed Tomography Angiography (CCTA). Patients were grouped based on quartiles of the TyG index. Logistic regression analysis and restricted cubic spline (RCS) regression models were used to evaluate the association between the TyG index and incomplete device endothelialization (IDE) postprocedure.

RESULTS

The TyG index was divided into four groups based on quartiles, with Group 1 (TyG index ≤ 8.17) serving as the reference. In Groups 3 (8.32 < TyG index ≤ 8.50) and 4 (TyG index > 8.50), the TyG index was identified as an independent risk factor for IDE postprocedure. The RCS model confirmed a significant linear relationship between the TyG index and IDE postprocedure. Furthermore, the association between the TyG index and IDE was consistent across different subgroups.

CONCLUSION

A higher TyG index was significantly associated with IDE after LAAO, suggesting that it could serve as a simple, cost-effective biomarker for predicting the risk of IDE in this population.

Optimal duration of anticoagulation after left atrial appendage closure: a systematic review and meta-analysis

BACKGROUND

Left atrial appendage closure (LAAC) has become the treatment of choice for stroke prevention in patients with nonvalvular atrial fibrillation who are at high risk of bleeding or with contraindications for anticoagulation. However, the optimal duration of anticoagulation after LAAC remains uncertain. The aim of this study was to evaluate the optimal duration of treatment with novel oral anticoagulants (NOACs) after LAAC.

METHOD

We searched the PubMed, Embase, Cochrane Library, and Web of Science databases for studies related to LAAC published from inception to 20 December 2023, and performed a meta-analysis comparing the efficacy and safety of 45-day and 3-month postoperative NOAC treatment using R4.3.1 software.

RESULTS

A total of 14 studies were included in this study, of which 4 were prospective cohort studies and 10 were retrospective cohort studies. The incidence of stroke or transient ischaemic attack (0.018 [95% CI: 0.007-0.033] in the 3-month group and 0.005 [95% CI: 0.001-0.011] in the 45-day group; P = 0.07) and the incidence of device-related thrombus (0.025 [95% CI: 0.002-0.065] in the 3-month group and 0.020 [ 95% CI: 0.007-0.037] in the 45-day group; P = 0.81) were not significantly different. However, the incidence of major bleeding was significantly greater in the 3-month group than in the 45-day group (0.033 [95% CI: 0.018-0.053] in the 3-month group and 0.003 [95% CI: 0.000-0.008] in the 45-day group; P < 0.01).

CONCLUSIONS

Compared with the 3-month scheme, 45 days of postoperative anticoagulation significantly reduced the risk of major bleeding in patients without compromising the efficacy of preventing stroke or transient ischaemic attack and device-related thrombus.

TRIAL REGISTRATION

Our meta-analysis was registered in the PROSPERO international database (CRD42024524661).

The safety and efficacy of left atrial appendage closure devices in patients with non-traumatic intracranial hemorrhage

INTRODUCTION

Anticoagulation in patients with atrial fibrillation and a history of intracranial hemorrhage (ICH) presents with challenges when balancing the risk of recurrent bleeding vs ischemic stroke. Left atrial appendage closure (LAAC) devices have shown promise as a minimally invasive method to prevent stroke without long-term anticoagulation. The goal of our study is to evaluate the efficacy of LAAC devices in patients with non-traumatic ICH and intraspinal hemorrhage which has not been well studied.

METHODS

A retrospective analysis on patients who had a history of atrial fibrillation and ICH/intraspinal hemorrhage was performed. The primary outcome was the development of new hemorrhage or ischemic stroke. Secondary outcomes included procedural complications and mortality.

RESULTS

103 patients were included with a mean follow-up time of 1341 ± 764 days. All patients had successful LAAC placement. 7 patients developed periprocedural complications including groin hematoma, stroke, and pericarditis. 43 had a peri-device leak of any size including 3 device related thrombus. 11 patients suffered a new ischemic stroke with an annualized incidence rate of 2.9 % and 6 suffered a recurrent hemorrhage with an annualized incidence rate of 1.6 %. Those who suffered a new stroke were more likely to have a history of prior stroke (p = 0.04) and had a larger peri-device leak (4.3 vs 2.7 mm, p = 0.04). There was no difference in patient characteristics in those who suffered an ICH.

CONCLUSION

LAAC devices appear to be a safe and effective alternative to anticoagulation in patients with a history of nontraumatic ICH or intraspinal hemorrhage.

Left atrial appendage occlusion in patients with cancer

Atrial fibrillation (AF) and malignancy share a complex relationship, significantly complicating patient management. Patients with cancer, particularly those with lung, gastrointestinal, genitourinary, and hematologic malignancies, are at increased risk of AF due to cancer-related hypercoagulability, proinflammatory cytokines, and treatment-related factors. This population faces unique thrombotic and bleeding risks, challenging standard management approaches. Anticoagulation is often complicated by drug-drug interactions with cancer therapies and heightened bleeding risks, including thrombocytopenia and coagulopathy. Left atrial appendage occlusion (LAAO) offers an alternative stroke prevention strategy for patients unable to tolerate long-term anticoagulation. By isolating the left atrial appendage, LAAO reduces thromboembolic risk while minimizing bleeding complications. Indications include patients with elevated stroke risk with contraindications to anticoagulation due to nonreversible causes, such as recurrent bleeding or significant drug interactions. Surgical LAAO may also be considered during cardiac surgery in patients with AF and high thromboembolic risk, with previous studies showing reduced risk of thromboembolic complications. Outcomes of LAAO in cancer patients are generally favorable, with studies showing comparable stroke rates, bleeding risks, and mortality to non-cancer populations. However, malignancy-specific complications, such as device-related thrombus, require further investigation. LAAO provides a promising option for stroke prevention in this complex population, but further research is needed to refine patient selection and optimize outcomes.

Reduced direct oral anticoagulant dose vs dual antiplatelet therapy after left atrial appendage closure in patients with nonvalvular atrial fibrillation: A systematic review and meta-analysis

BACKGROUND

Left atrial appendage closure (LAAC) is an alternative therapy for patients with nonvalvular atrial fibrillation who are not eligible for long-term oral anticoagulation. However, the optimal therapy after this procedure still is controversial, especially in a subgroup of patients with severe renal dysfunction.

OBJECTIVE

The purpose of this study was to evaluate the use of low-dose direct oral anticoagulation (l-DOAC) vs dual antiplatelet therapy (DAPT) after LAAC in patients with nonvalvular atrial fibrillation.

METHODS

We systematically searched PubMed, Embase and Cochrane. Outcomes were the incidence of device-related thrombus (DRT), major bleeding, stroke, cardiovascular mortality, all-cause mortality, thromboembolic events (DRT, ischemic stroke, transient ischemic attack, peripheral thromboembolism), and the composite outcome of thromboembolic events and major bleeding. Risk ratios (RRs) with 95% confidence intervals (CIs) were calculated using a random effects model. Review Manager 5.4.1 was used for statistical analyses. Heterogeneity was assessed with I2 statistics.

RESULTS

A total of 1015 participants from 2 randomized controlled trials and 3 nonrandomized cohorts were included. The incidence of DRT was significantly reduced with l-DOAC relative to DAPT (0.81% vs 5.08%, respectively; RR 0.37; 95% CI 0.15-0.94; P = .04; I2 = 0%). We also found the patients who used l-DOAC had a reduction in the composite outcomes of thromboembolic events and major bleeding (1.41% vs 11.13%; RR 0.14; 95% CI 0.05-0.36; P <.0001; I2 = 0%).

CONCLUSION

In this systematic review and meta-analysis, the use of l-DOACs in patients with nonvalvular atrial fibrillation who underwent LAAC reduces the occurrence of the DRT and composite outcomes of thromboembolic events and major bleeding.

Clinical and subclinical acute brain injury caused by invasive cardiovascular procedures

Over the past 50 years, the number and invasiveness of percutaneous cardiovascular procedures globally have increased substantially. However, cardiovascular interventions are inherently associated with a risk of acute brain injury, both periprocedurally and postprocedurally, which impairs medical outcomes and increases health-care costs. Current international clinical guidelines generally do not cover the area of acute brain injury related to cardiovascular invasive procedures. In this international Consensus Statement, we compile the available knowledge (including data on prevalence, pathophysiology, risk factors, clinical presentation and management) to formulate consensus recommendations on the prevention, diagnosis and treatment of acute brain injury caused by cardiovascular interventions. We also identify knowledge gaps and possible future directions in clinical research into acute brain injury related to cardiovascular interventions.

Current evidence and indications for left atrial appendage closure

Atrial fibrillation (AF) is the most common arrhythmia worldwide and its prevalence increases with age. The main and most severe complication of AF is ischemic stroke, yet an estimated 50 % of eligible patients cannot tolerate or are contraindicated to receive oral anticoagulation (OAC). In patients with AF, the left atrial appendage (LAA) is the main source of thrombus formation. Percutaneous LAA closure (LAAC) has emerged over the past two decades as a valuable alternative to OAC for reducing the risk of strokes and systemic embolisms in patients with AF who cannot tolerate long-term OAC. With newer generation devices such as the Watchman (Boston Scientific, Natick, MA, USA) and Amulet (Abbott, Abbott Park, IL, USA) gaining approval from the US Food and Drug Administration in recent years, the safety and efficacy of LAAC in specific populations intolerant to OAC have increased and more patients are being treated. This systematic review provides the indications for LAAC and the evidence for evaluating the use of the currently available device therapies. We also examine the current unsolved problems with patient selection and postprocedural antithrombotic regimens.

Percutaneous Left Atrial Appendage Closure: Supporting Evidence, Limitations and Future Directions

Percutaneous Left Atrial Appendage Occlusion (LAAO) has emerged as a promising intervention for stroke prevention in patients with atrial fibrillation who are contraindicated for long-term anticoagulation therapy. Despite its growing adoption, a comprehensive review of the LAAO procedure is essential to consolidate the supporting evidence, identify limitations, and outline future directions. This review aims to evaluate the efficacy and safety of LAAO, drawing on clinical trials and real-world studies to provide a balanced perspective. Additionally, we address the limitations of current research, including variability in patient selection, procedural techniques, and follow-up protocols. By highlighting gaps in the knowledge and areas for improvement, this review aims to guide future research efforts to optimize and expand the therapeutic potential of LAAO.

Three-Dimensional-Printed Models Reduce Adverse Events of Left Atrial Appendage Occlusion: A Systematic Review and Meta-Analysis

BACKGROUND AND AIMS

Left atrial appendage occlusion (LAAO) has an excellent safety profile but there is growing evidence of adverse long-term sequelae of peri-device leak and device-related thrombus. This study seeks to determine if guidance from 3D-printed models of left atrial appendages reduces the incidence of side effects.

METHODS

A systematic literature search was conducted in the following databases: Pubmed, Google Scholar, and Europe PMC. Cohort studies that directly compared outcomes using 3D-printed model simulations before undergoing LAAO versus using conventional imaging only among patients with nonvalvular atrial fibrillation, CHA2DS2-VASc scores ≥ 1, and relative or absolute contraindications to long-term anticoagulation were included. Clinical outcomes included incidence of peri-device leak, mismatch, and device-related thrombus. Meta-analysis was done using the random-effects model.

RESULTS

Only three cohort studies were eligible for meta-analysis with a mean follow-up period of 25 months. This included a total of 204 patients (mean age, 75 years). Using 3D printed models of left atrial appendage based on transesophageal echocardiogram and cardiac computed tomography had statistically significantly less incidence of peri-device leak (log OR -2.47; 95% CI: -3.70 to 1.24; p = 0.00), incidence of mismatch (log OR -1.61; 95% CI: -2.50 to 0.73; p = 0.00) and shorter procedural time (mean difference -24.86; 95% CI: -31.75 and -27.11; p = 0.00). Although the incidence of device-related thromboembolism was 49% less in the 3D printing-guided group, the difference was not statistically significant (p = 0.58).

CONCLUSION

Less incidence of peri-device leak and mismatch were observed with 3D printing-guided left atrial appendage occlusion. A highly powered randomized controlled trial may have to be done to confirm the findings.

Characterization and Clinical Outcomes of High-Risk Device-Related Thrombus in the Amulet IDE Trial

BACKGROUND

Characteristics of device-related thrombus (DRT) may differ between types of left atrial appendage occlusion devices, and the association of different DRT characteristics to clinical outcomes is largely unknown.

OBJECTIVES

The incidence, characteristics, and clinical outcomes through 5 years of high- and low-risk DRTs were assessed in the Amulet IDE trial (AMPLATZER Amulet Left Atrial Appendage Occluder [LAAO] Investigational Device Exemption [IDE] Trial).

METHODS

An independent core laboratory analyzed all available images at the required 45-day and 12-month visits, and clinical events were reported through 5 years' post-left atrial appendage occlusion.

RESULTS

Of the 1,788 patients with a successful device implant, DRT was observed in 3.3% (30 of 903) and 4.5% (40 of 885) of Amulet and Watchman 2.5 device patients throughout 12 months, respectively (P = 0.192). DRTs were successfully classified as high risk if pedunculated, mobile, >3 mm in thickness, or without continuation onto the left atrial wall. A significantly higher incidence of high-risk DRTs was observed on the Watchman 2.5 device (4.0% [35 of 885]) compared with the Amulet occluder (2.2% [20 of 903]) (P = 0.030). Most low-risk DRTs resolved (12 of 15), whereas high-risk DRTs remained mostly unresolved (34 of 55). Through 5 years, all clinical outcome rates were numerically higher in the high-risk DRT group compared with the low-risk DRT or no-DRT group; significance was observed in the composite of stroke, systemic embolism, or cardiovascular death (30.4% vs 19.9%; HR: 1.74; 95% CI: 1.03-2.92; P = 0.037) and cardiovascular death (26.4% vs 14.5%, HR: 2.09; 95% CI: 1.20-3.66; P = 0.009).

CONCLUSIONS

High-risk DRTs were observed in a higher number of Watchman 2.5 device patients compared with Amulet occluder patients. The composite of stroke, systemic embolism, or cardiovascular death occurred more often in patients with high-risk DRTs compared with those with low-risk DRTs or no DRTs. (AMPLATZER Amulet Left Atrial Appendage Occluder [LAAO] Investigational Device Exemption [Amulet IDE Trial]; NCT02879448).

Epicardial Ligation of the Left Atrial Appendage in Octogenarians: Safety and Long-Term Efficacy

Introduction: Due to the aging population, the number of elderly patients with atrial fibrillation and contraindications for anticoagulation due to bleeding complications is growing. After the epicardial ligation of the left atrial appendage (LAA), anticoagulation can be omitted. We present the single-center procedure data and long-term data of octogenarians being treated with LARIAT®. Method: Out of 145 patients eligible for the epicardial ligation of the LAA, 45 were older than 80 y and included in this analysis. After successful ligation, patients were screened at 6 weeks of follow-up (FUP), at 12 weeks and after 12 months for transesophageal echocardiography (TOE) and clinical events. During long-term FUP, TOE sessions and clinical events for embolic events and death were documented. Results: The procedure was successful in 93% of patients, with a mean CHA2DS2VASC score of 4.6 and HASBLED score of 3.7 and a mean age of 82 y. One major complication occurred, with the laceration of the LAA and surgical closure of the LAA with an Atriclip. The 6-week FUP data were available in 39 patients, with the detection of four leaks (1-3 mm, median 2 mm) and three thrombi; one thrombus occurred at the site of a leak. The 12-week FUP (in 26 patients) showed that three leaks were closed, one leak persisted and one new thrombus developed at the site of the leak. All thrombi were resolved. The 12-month FUP showed the persistent resolution of three thrombi; one thrombus recurred after the withdrawal of the anticoagulant, and no new gap or thrombus could be detected. The long-term FUP (mean 38 months) was documented in 30 patients, with no new gaps and no new thrombi; one patient suffered from a stroke, with a good long-term result of LAA closure in TOE (stroke rate 1%/y, absolute risk reduction of 4.4% to a stroke rate of 5.4% related to the score, relative CHA2DS2VASC risk reduction of 88%). Eleven patients died: four in the first year of ligation and seven during long-term FUP. Conclusions: The epicardial ligation of the LAA for stroke prevention in octogenarians is highly safe and effective. Early TOE FUP is crucial for the detection of thrombi and establishing an optimal anticoagulation regime. No late development of thrombi or gaps can be observed at up to 5 years.

Left Atrial Appendage Closure: What Do We Know?

Atrial fibrillation (AF) is the most common arrhythmia in the United States and the most common cause of embolic cerebrovascular events, with the majority of these thrombi originating in the left atrial appendage. The left atrial appendage (LAA) has separate developmental, ultrastructural, and physiological characteristics from the left atrium. Although LAA anatomy is highly variable, it can be categorized into 4 types: cactus, cauliflower, chicken wing, and windsock. The cauliflower type is associated with higher stroke risk in patients with nonvalvular AF. Although the cornerstone of therapy to prevent embolic strokes from AF has been anticoagulation with thrombin inhibitors, a large group of patients are unable to tolerate anticoagulation due to bleeding. This has led to the development and advancement of multiple surgical and percutaneous LAA closure devices to prevent embolic cerebrovascular accidents without the need for anticoagulation. In this article, we discuss the outcomes of major studies that utilized surgical LAA occlusion and its effectiveness. Furthermore, we summarize nonsurgical methods of LAA closure and future directions regarding LAA closure.

State of the Art in Left Atrial Appendage Occlusion

Left atrial appendage occlusion (LAAO) has become an important therapeutic target for stroke prevention in patients with nonvalvular atrial fibrillation. Over the past 2 decades, several advancements in LAAO devices (percutaneous and surgical) have been made for stroke prevention and arrhythmia therapy. However, there are several unanswered questions regarding optimal patient selection, the preferred LAAO approach and device, the management of periprocedural and postprocedural complications, including pericardial effusion, device-related thrombus, and device leaks. This review focuses on fundamental foundational concepts in various aspects of the left atrial appendage and management strategies as they relate to current clinical needs.

Percutaneous left atrial appendage closure for stroke prevention: current challenges and future perspectives

Stroke accounts for significant morbidity and mortality worldwide. Accordingly, appropriate prevention is crucial to reduce the global burden of stroke. Percutaneous left atrial appendage closure (LAAC) is a viable approach for preventing cardioembolic stroke in patients with non-valvular atrial fibrillation who have a contraindication to long-term oral anticoagulation due to a non-reversible cause. In the last 2 decades, percutaneous LAAC has become a rapidly evolving field, with multiple devices approved or under clinical development. However, several issues remain, including limited high-quality evidence, late adverse events, and unclear post-procedural antithrombotic therapy. This review offers an up-to-date perspective on percutaneous LAAC, concentrating on current challenges and unmet needs.

Drop-shaped microgrooves guide unidirectional cell migration for enhanced endothelialization

Atrial fibrillation (AF) significantly increases the risk of ischemic stroke, and in non-valvular AF, 90% of stroke-causing thrombi arise from the left atrial appendage (LAA). Percutaneous LAA occlusion using an occluder is a crucial clinical intervention. However, occluder materials could provoke thrombi, termed device-related thrombosis (DRT), leading to treatment failure. Rapid endothelialization is essential to address the DRT but the occluder's large surface area and irregular cell migration on the surface impede this process. Here, we report a continuous drop-shaped microgroove, which has a drop-shaped unit structure similar to endothelial cells. The microgrooves polarize the cytoskeleton, guiding cell unidirectional migration within the grooves, and increase cell migration efficiency. We show that drop-shaped microgrooves accelerate wound healing in a rat model, and that occluder discs with drop-shaped microgrooves promote endothelialization in a canine model. Together, our results show that integrating microgrooves with medical devices is a promising approach for addressing DRT.

Comparison of prognosis and analysis of related risk factors among three different left atrial appendage occlusion procedures in patients with atrial fibrillation

Background

Left atrial appendage occlusion (LAAO) serves as an alternative to oral anticoagulation (OAC) for atrial fibrillation (AF) patients at high risk of bleeding. The aim of this study was to compare the peri-procedural safety, complete or incomplete occlusion, the incidence of the peri-device leak (PDL), and device-related thrombosis (DRT) among LAAO, cryoballoon ablation (CBA) combined with LAAO, and radiofrequency catheter ablation (RFCA) combined with LAAO and to explore the risk factors of PDL and incomplete occlusion.

Methods

382 patients with non-valvular AF who underwent either LAAO alone (n = 117), CBA combined with LAAO (n = 125), or RFCA combined with LAAO (n = 140) were included in the retrospective study. The study assessed peri-procedural complications and imaging results (3 months post-procedure). Multivariable logistic regression was employed to identify risk factors for incomplete occlusion and PDL.

Results

Peri-procedural complication rates were low among all groups, with 2.9% in the RFCA combined with the LAAO group. In contrast, the LAAO alone and CBA combined with LAAO groups reported no major complications (p = 0.347). At the 3-month follow-up, the incidence of DRT was 1.7% in the LAAO group, 2.4% in the CBA combined with the LAAO group, and 2.1% in the RFCA combined with the LAAO group (p = 0.930). Complete occlusion rates were comparable among the groups: 64.8% for CBA combined with LAAO, 62.4% for LAAO alone, and 60.7% for RFCA combined with LAAO (p = 0.794). PDL occurred in 33.3% of LAAO-alone patients, 34.4% of CBA combined with LAAO patients, and 38.6% of RFCA combined with LAAO patients (p = 0.644). Multivariable analysis identified persistent AF and serum creatinine (SCr) as independent predictors of PDL and incomplete occlusion.

Conclusion

Peri-procedural complications, complete occlusion, PDL, and DRT rates were similar across the three treatment strategies. Persistent AF and SCr were significant risk factors for incomplete occlusion and PDL. These findings highlight the importance of individualized treatment strategies based on patient-specific risk factors for optimizing outcomes.

Step-by-Step ICE-Guided Aspiration Thrombectomy: Gastrointestinal Bleeding Patient With Device-Related Thrombus on Watchman FLX

Objectives

Device-related thrombus (DRT) remains a significant complication in the field of left atrial appendage occlusion (LAAO). In patients who have difficulty tolerating long-term anticoagulation, treatment options are limited. We present a step-by-step intracardiac echocardiography (ICE)-guided AngioVac (AngioDynamics) challenging case in a 71-year-old woman with a gastrointestinal bleeding tendency and a highly mobile thrombus on a Watchman FLX device (Boston Scientific).

Key Steps

We obtained a 26-F DrySeal (Gore Medical) venous access, a 15-F extracorporeal membrane oxygenation cannula arterial access, and a 3-dimensional ICE access. We performed a challenging transseptal crossing using an Agilis medium curl catheter (Abbott) and an electrified Astato wire (Asahi Intecc Medical) as a result of a severely hypertrophic lipomatous septum. We snared the ICE catheter across the interatrial septum (IAS) with a 35-mm gooseneck snare in the inferior vena cava. We used a balloon-assisted technique to bring the F-18 AngioVac system across the IAS. The helicoptering technique with a J-wire assisted with suction of the DRT.

Potential Pitfalls

Currently, there are no data to support which post-LAAO antithrombotic regimen predicts DRT. For patients who are unable to tolerate long-term anticoagulation, treatment options are limited. To our knowledge, this is the first reported ICE-guided LAAO thrombus aspiration.

Take-Home Messages

ICE-guided aspiration thrombectomy of LAAO thrombus is feasible in high-risk patients who cannot tolerate long-term oral anticoagulation and to reduce the risk of clot embolization.

Design and Validation of a High-Fidelity Left Atrial Cardiac Simulator for the Study and Advancement of Left Atrial Appendage Occlusion

PURPOSE

Atrial fibrillation (AF) is the most common chronic cardiac arrhythmia that increases the risk of stroke, primarily due to thrombus formation in the left atrial appendage (LAA). Left atrial appendage occlusion (LAAO) devices offer an alternative to oral anticoagulation for stroke prevention. However, the complex and variable anatomy of the LAA presents significant challenges to device design and deployment. Current benchtop models fail to replicate both anatomical variability and physiological hemodynamics, limiting their utility. This study introduces a novel left atrial cardiac simulator that incorporates patient-derived LAA models within a benchtop circulatory flow loop, enabling high-fidelity LAAO device testing and development.

METHODS

A rigid, patient-derived left atrium (LA) model was 3D printed from segmented MRI data and modified to accommodate attachment of patient-specific LAA models. A library of LAA geometries was fabricated using silicone casting techniques to replicate the mechanical properties of native tissue. The LA-LAA model was integrated into a circulatory flow loop equipped with a pulsatile pump, pressure sensors, and flow probes, allowing real-time hemodynamic analysis. System tunability was demonstrated by varying heart rate, stroke volume, resistance, and compliance to simulate physiological and pathological conditions.

RESULTS

The simulator accurately replicated LA pressure and flow waveforms, closely approximating physiological conditions. Changes in heart rate, stroke volume, and compliance effectively modulated LAP and LA inflow before and after LAAO. Distinct pressure and flow waveforms were observed with different LAA geometries. Hemodynamic analysis revealed increased left atrial pulse pressure after occlusion, with the greatest increase occurring after complete exclusion of the LAA. The simulator facilitated the evaluation of LAAO device performance, including metrics such as seal and PDL, and served as an effective training tool for iterative device deployment and recapture with visual and imaging-guided feedback.

CONCLUSIONS

The left atrial cardiac simulator offers a highly tunable and realistic platform for testing and developing LAAO devices. It also serves as an effective procedural training tool, allowing for the simulation of patient-specific anatomical and hemodynamic conditions. By enabling these advanced simulations, the simulator enhances pre-procedural planning, device sizing, and placement. This innovation represents a significant step toward advancing personalized medicine in atrial fibrillation management and improving LAAO outcomes.

WATCHMAN versus LACbes® device for percutaneous left atrial appendage closure: a single-center, propensity-matched study

BACKGROUND

Different left atrial appendage closure (LAAC) devices have been introduced into the clinical setting. A new dual-seal mechanism LACbes® occluder with isogenous barbs for LAAC has been designed to facilitate easier delivery and improve safety. The purpose of this study is to compare the clinical outcomes of the WATCHMAN with those of the LACbes® device for LAAC.

METHODS

Consecutive patients with atrial fibrillation (AF) who had undergone LAAC performed using a WATCHMAN or LACbes® device from June 2016 to February 2022 were included. The primary efficacy endpoint included ischemic stroke, cardiovascular/unexplained death and device-related thrombus, while the primary safety endpoint included major peri-procedural complications and major bleeding events during clinical follow-ups. 1:1 propensity score matching (PSM) was performed.

RESULTS

After PSM, 184 patients were included in each group. The mean CHA2DS2-VASc score was 3.1 ± 1.5 (LACbes®) vs. 3.1 ± 1.4 (WATCHMAN), and the HAS-BLED score was 2.7 ± 1.1 vs. 2.7 ± 1.0. At a mean follow-up of 2.5 ± 1.5 vs. 2.4 ± 0.9 years, the defined three endpoints were comparable between the two groups. The occurrence of all-cause stroke was lower in 5/452 (1.8%) with LACbes® vs. 16/433 (3.7%) with WATCHMAN occluders (HR, 0.40, 95% confidence interval (CI), 0.18-0.89, P = 0.023), and the incidence of any bleeding was higher in the WATCHMAN group (41/433, 9.5% vs. 8/452, 1.8%; HR, 0.19, 95% CI, 0.11-0.33).

CONCLUSION

The LACbes® occluder exhibited comparable safety and efficacy of stroke prevention for AF when compared with the WATCHMAN device.

Clinical effectiveness and safety comparison between direct oral anticoagulants and warfarin for nonvalvular atrial fibrillation patients following percutaneous left atrial appendage closure operation intervention: a prospective observational study

The main objective of this study was to investigate the optimal post-left atrial appendage closure (LAAC) anticoagulation strategy, focusing on minimizing device-related thrombosis (DRT) and thromboembolism (TE) events without increasing bleeding risk. After successful LAAC, consecutive participants were treated with 45-day anticoagulants (rivaroxaban 15 mg daily, dabigatran 110 mg twice a day, and warfarin). The efficacy endpoints included DRT, TE, and hospital readmissions due to cardiac caused, while safety endpoints encompassed bleeding events, monitored over a 12-month follow-up period. The incidence of DRT was relatively lower in the rivaroxaban group compared to both the dabigatran and warfarin groups (rivaroxaban vs. dabigatran: HR = 0.504, 95% CI 0.208-1.223, log-rank P = 0.101; rivaroxaban vs. warfarin: HR = 0.468, 95% CI 0.167-1.316, log-rank P = 0.093). The median [interquartile range] length and width of DRT in the rivaroxaban group were 1.92 [1.68-2.15] mm and 1.49 [1.28-1.76] mm, both significantly lower than those in the dabigatran (length = 2.15 [1.99-2.25] mm, P = 0.036; width = 1.60 [1.54-1.85] mm, P = 0.035) and warfarin groups (length = 2.26 [2.11-2.44] mm, P = 0.006; width = 1.74 [1.54-1.85] mm, P = 0.006). Kaplan-Meier survival analysis indicated that procedural bleeding was more common in the warfarin group. The 12-month incidence of TE was significantly lower in the rivaroxaban group compared to the dabigatran (HR = 0.466, 95% CI 0.221-0.984, log-rank P = 0.029) and warfarin groups (HR = 0.456, 95% CI 0.188-0.966, log-rank P = 0.042). Long-term antithrombotic therapy with reduced dose of rivaroxaban significantly reduced the risk of DRT and composite endpoints without increasing bleeding events, compared to warfarin and dabigatran, for patients following LAAC.

Left Atrial Appendage Occlusion: Expanding Indications and New Developments

Percutaneous left atrial appendage occlusion (LAAO) is recommended in several major international society guidelines as a viable alternative to therapeutic anticoagulation for the prevention of ischemic stroke in patients with nonvalvular atrial fibrillation or flutter. Recent innovations in device development have improved the safety and procedural success of LAAO, further fueling enthusiasm for expanding its indications beyond patients with high-bleeding risk from oral anticoagulation use. It is the aim of this review to provide historical context in addition to recent updates and upcoming developments and provide practical suggestions on how best to care for patients who are candidates for LAAO in contemporary practice. Recent data comparing the safety and efficacy of post-LAAO antiplatelet vs. antithrombotic therapy will be highlighted, with specific recommendations regarding which patients are best suited for each strategy. We will also address the safety and practical considerations provided by emerging trials on concomitant LAAO during other structural heart interventions such as transcatheter aortic valve replacement and mitral valve interventions, as well as electrophysiology procedures including catheter ablation for atrial fibrillation and pacemaker implantation. Practical considerations for the use of transesophageal echocardiography or intracardiac echocardiography for procedural guidance will also be discussed. As the evidence supporting LAAO continues to evolve, this review will serve as a primer on the recent and upcoming advances in device technology and management strategies positioned to further push LAAO forward into the future.

An International Consensus Practical Guide on Left Atrial Appendage Closure for the Non-implanting Physician: Executive Summary

Many patients with atrial fibrillation (AF) who are in need of stroke prevention are not treated with oral anticoagulation or discontinue treatment shortly after its initiation. Despite the availability of direct oral anticoagulants (DOACs), such undertreatment has improved somewhat but is still evident. This is due to continued risks of bleeding events or ischemic strokes while on DOAC, poor treatment compliance, or aversion to anticoagulant therapy. Because of significant improvements in procedural safety over the years left atrial appendage closure (LAAC), using a catheter-based, device implantation approach, is increasingly favored for the prevention of thromboembolic events in AF patients who cannot have long-term oral anticoagulation. This article is an executive summary of a practical guide recently published by an international expert consensus group, which introduces the LAAC devices and briefly explains the implantation technique. The indications and device follow-up are more comprehensively described. This practical guide, aligned with published guideline/guidance, is aimed at those non-implanting physicians who may need to refer patients for consideration of LAAC.

Transfabric Leaks After Percutaneous Left Atrial Appendage Occlusion Procedures with the WATCHMAN FLX Device

Background

Cardiac computed tomography imaging with contrast is being used increasingly to image left atrial appendage occlusion (LAAO) devices. Contrast flow across a device, also known as a transfabric leak (TFL), may indicate a lack of complete LAAO-device endothelialization. The data on the rate, predictors, and clinical events associated with TFL are limited.

Methods

All patients who underwent an LAAO-device implantation with a WATCHMAN FLX device and received a postimplantation computed tomography scan were included in this single-centre retrospective cohort study. Patients were classified as either having or not having a TFL, according to 3 currently proposed definitions of TFL. Clinical and procedural differences between the 2 groups were determined. An exploratory univariate logistic regression model to evaluate predictors of TFL was constructed.

Results

A total of 56 individuals were included in the cohort. The rate of TFL varied from 27% to 52%, depending on the radiographic definition employed. No clinically important patient or procedural characteristics were noted between the groups with vs without TFL. No predictors of TFL were identified. Six deaths and one stroke occurred during a median follow-up period of 673 days.

Conclusions

TFLs occur commonly post-LAAO procedures, suggesting that complete endothelialization of LAAO devices in humans may not be similar to that reported in animal models. Additional study into the best imaging approach to identify TFLs, and clinical events associated with TFLs, is necessary to clarify the significance of TFLs.

Comparative Endothelialization of the Watchman Plug Device and LACBES Pacifier Occluder after Left Atrial Appendage Closure

Background

For patients with nonvalvular atrial fibrillation (NVAF), left atrial appendage closure (LAAC) is an alternative to oral anticoagulants (OACs). However, incomplete device endothelialization (IDE) after LAAC has been linked to device-related thrombus (DRT) and subsequent thromboembolic events. Here, the differences in device endothelialization between the Watchman plug device and the LACBES pacifier occluder after implantation were investigated.

Methods

Of 201 consecutive patients with indications for LAAC, 101 received a Watchman 2.5 device, and 100 received a LACBES occluder. IDE was defined as a residual flow of contrast agent inside the left atrial appendage (LAA) on cardiac computed tomography angiography (CCTA) without peri-device leak (PDL) at the 3-month and 6-month follow-ups.

Results

There were no significant differences in DRT or PDL incidence between the two groups. However, the IDE rate in the absence of PDL was higher in the LACBES group than in the Watchman group at 3 months (42.4% versus 25.8%; p = 0.025) and at the 6-month follow-up (24.7% versus 11.2%; p = 0.028) as determined by CCTA.

Conclusions

Our findings indicated that the LACBES occluder took longer to complete endothelialization than the Watchman device after successful LAAC therapy. CCTA is a reliable imaging method for assessing the sealing of LAAC devices and confirming complete device endothelialization.

Association between preprocedural thromboembolic and bleeding events under oral anticoagulation therapy and mid-term outcomes after percutaneous left atrial appendage closure

Currently, no consensus has been established on the most effective antithrombotic therapy to prevent thromboembolic and bleeding events in patients undergoing percutaneous left atrial appendage closure (LAAC) with preprocedural thromboembolic or bleeding events under oral anticoagulation (OAC) therapy. We retrospectively investigated the incidence of device-related thrombosis (DRT), thromboembolic events, and bleeding events in patients who underwent LAAC from September 2019 to October 2022. After categorizing patients into three groups based on preprocedural thromboembolic or bleeding events under OAC therapy, we compared the incidence of DRT and prognosis according to the postprocedural antithrombotic therapy. In patients who received the conventional antithrombotic therapy (OAC with and without single antiplatelet therapy for 45 days after LAAC and dual-antiplatelet therapy from 45 days to 6 months followed by single antiplatelet therapy), preprocedural thromboembolic events despite OAC were independently associated with DRT or postprocedural thromboembolic events at the 3 year follow-up (hazard ratio [HR] 4.55; 95% confidence interval [CI] 1.32-15.6; P = 0.016), whereas preprocedural bleeding events were independently associated with postprocedural bleeding events (HR 8.01, 95% CI 1.45-58.3; P = 0.036). Continuation of OAC for 12 months among patients who developed preprocedural thromboembolic events during OAC significantly decreased the incidence of DRT or postoperative thromboembolic events (P = 0.002) with no increase in the bleeding events (P = 0.522). Preprocedural thromboembolic and bleeding events can predict adverse events after LAAC with the conventional antiplatelet-based antithrombotic therapy. Patients who develop thromboembolic events under continuous OAC may benefit from continuous OAC for 1 year after LAAC.

Cerebral Embolic Protection: Is There a Benefit for Left Atrial and Mitral Valve Procedures?

PURPOSE OF REVIEW

This review aims to highlight the current evidence on the use of cerebral embolic protection devices (CEPD) in left atrial and transcatheter mitral valve procedures. It also aims to summarize the antithrombotic management of patients undergoing such procedures.

RECENT FINDINGS

Ischemic stroke is one of the most devastating complications of structural heart procedures. The manifestation of periprocedural stroke can range from asymptomatic and detectable only through brain imaging to major stroke with neurological deficits. CEP devices were initially developed to mitigate the risk of stroke associated with transcatheter aortic valve replacement (TAVR). However, the efficacy of such devices during different cardiac interventions is yet to be fully demonstrated, especially in left atrial appendage closure (LAAO), and mitral valve interventions. Few studies demonstrated that the risk of periprocedural strokes after LAAO and mitral valve interventions is not negligible and is highest during the periprocedural period and then falls. The majority of patients undergoing those procedures have cerebral ischemic injuries detected on diffusion-weighted magnetic resonance imaging (DW-MRI). Moreover, a reasonable number of those patients had debris embolization on the filters of the CEPD. Pharmacological therapy with antithrombotic agents before, during, or after structural heart interventions is crucial and should be tailored to each patient's risk of bleeding and ischemia. Close monitoring that includes a full neurological assessment and frequent follow-up visits with cardiac echocardiography are important. The risk of periprocedural stroke in left atrial and transcatheter mitral valve procedures is not negligible. Pharmacological therapy with antithrombotic agents before, during, or after structural heart interventions is important to mitigate the risk of stroke, especially the long-term risk. More prospective studies are needed to assess the efficacy of CEPD in such procedures.

Advancements in 3D Transoesophageal Echocardiography (TOE) and Computed Tomography (CT) for Stroke Prevention in Left Atrial Appendage Occlusion Interventions

Left atrial appendage occlusion (LAAO) has emerged as a highly effective alternative to oral anticoagulation for stroke prevention in patients with non-valvular atrial fibrillation. Precise pre-procedural planning and meticulous post-procedural follow-up are essential for achieving successful LAAO outcomes. This review explores the latest advancements in three-dimensional (3D) transoesophageal echocardiography (TOE) and computed tomography (CT) imaging modalities, which have considerably improved the planning, intra-procedural guidance, and follow-up processes for LAAO interventions. Innovations in 3D TOE and CT imaging have transformed the approach to LAAO by providing a more detailed and accurate assessment of the left atrial appendage, enabling clinicians to acquire comprehensive anatomical and morphological information, crucial for optimising device selection and positioning, thus reducing the risk of complications and enhancing the overall safety and efficacy of the procedure. Post-procedurally, CT and TOE imaging are invaluable in the monitoring of patients, ensuring that the device is correctly positioned and functioning as intended. Early detection of any complications (e.g., device-related thrombus and peri-device leaks) can help to risk-stratify patient at increased risk of stroke and initiate timely interventions, thereby improving long-term outcomes for patients.

Zero-contrast left atrial appendage closure, a feasible alternative for patients with a high risk of contrast-induced nephropathy: Systematic literature review and meta-analysis

BACKGROUND

Left atrial appendage closure (LAAC) is an alternative to reduce thrombotic risk in patients with nonvalvular atrial fibrillation. This procedure conventionally requires the use of a contrast agent. A significant proportion of patients who undergo this procedure have chronic kidney disease, with a high risk of contrast-induced nephropathy.

OBJECTIVE

We aimed to systematically review existing literature regarding the feasibility and safety of a zero-contrast LAAC technique.

METHODS

We searched the MEDLINE/PubMed, Embase, and Cochrane Central Register of Controlled Trials databases for studies comparing a zero-contrast LAAC technique with conventional LAAC up to April 2024. From each study, we extracted baseline characteristics, feasibility, and safety outcomes. A random model meta-analysis was used to compare outcomes between groups.

RESULTS

Five studies reporting data from 367 patients were included. A 100% successful implantation rate was reported in all the zero-contrast groups. The mean number of recaptures reached no significant difference between the groups (mean difference, -0.15; CI, -0.67 to 0.37; I2 = 0%; P = .58). The zero-contrast group had a significantly shorter fluoroscopy time (mean difference, -4.03; CI, -7.72 to -0.34; I2 = 67%; P = .03). Complications related to the procedure, peridevice leak, and device-associated thrombus rates were not significantly different between the groups.

CONCLUSION

Zero-contrast LAAC is a feasible alternative. The success and complication rates are consistent with those of conventional LAAC. Aside from the inherent benefit of zero-contrast exposure, this technique allows a reduction in fluoroscopy time.

Left Atrial Appendage Closure With Catheter Ablation vs. Ablation Alone on Outcomes of Atrial Fibrillation in Heart Failure With Reduced Ejection Fraction: A Propensity Score-Matched Analysis

Background Combining left atrial appendage closure with catheter ablation (LAACCA) has been proposed as a potential approach to improving outcomes by simultaneously addressing arrhythmia and reducing stroke risk. This study compares the in-hospital outcomes of LAACCA vs. catheter ablation (CA) alone for atrial fibrillation (AFib) in patients with heart failure with reduced ejection fraction (HFrEF). Methods We analyzed adult hospitalizations with HFrEF and AFib who underwent LAACCA or CA alone from the 2016-2020 nationwide inpatient sample using validated ICD-10 codes. Propensity score matching, accounting for patient-, hospital-, and procedure-level covariates, illness severity, and baseline risk of mortality, was used to alleviate bias in nonrandomized treatment assignments. The primary endpoints included all-cause in-hospital mortality, hospital stay, and hospitalization costs. Secondary endpoints included postprocedural complication rates. Prolonged hospitalization was defined as hospital stay in the top decile of hospital stay in each cohort. All statistical analyses in the study were based on weighted hospital data. Results About 233,865 HFrEF patients were hospitalized for AFib. Approximately 27,945 (11.9%) underwent LAACCA, while 205,920 (88.1%) underwent CA only. The cohort comprised mostly males (151,077; 64.6%) (mean age: 67.4; SD: 4.3). The propensity score-matched cohort comprised 18,195 LAACCAs and 18,195 CAs; all covariate imbalances were alleviated. LAACCA was associated with a higher rate of prolonged hospital stay (7.6 vs 5.6 days; P<0.001), a higher mortality rate (209 (1.1%) vs. 160 (0.9%); P=0.011), and higher mean hospital costs ($289,960 vs. $183,932; P<0.001) compared with CA alone. LAACCA was associated with a higher incidence of acute myocardial ischemia (528 (2.9%) vs. 455 (2.5%); P=0.013), complete atrioventricular block (1,200 (6.6%) vs. 892 (4.9%); P=0.004), need for implantable device therapy (1,510 (8.3%) vs. 1,348 (7.4%); P=0.017), pneumothorax (328 (1.8%) vs. 91 (0.5%); P<0.0001), hemothorax (200 (1.1%) vs. 127 (0.7%); P<0.0001), pneumonia (983 (5.4%) vs. 546 (3.0%); P<0.0001), vascular access complications (346 (1.9%) vs. 255 (1.4%); P=0.046), and septicemia (309 (1.7%) vs. 182 (1.0%); P<0.001). CA was associated with a greater incidence of cardiac tamponade (237 (1.3%) vs. 382 (2.1%); P=0.010) and femoral artery pseudoaneurysm (364 (0.2%) vs. 91 (0.5%); P<0.001). Conclusion LAACCA was correlated with higher mortality odds compared to CA alone for atrial fibrillation in HFrEF.

Predictors of Device-Related Thrombus After Left Atrial Appendage Occlusion: TED-F2 Score

Background

Left atrial appendage (LAA) occlusion (LAAO) is performed to prevent LAA thrombus in patients with atrial fibrillation (AF). The risk of device-related thrombus (DRT) on the atrial side of the LAAO device is approximately 4%. Identifying patients at high risk of DRT would enable closer surveillance and more-aggressive anticoagulation to prevent post-LAAO DRT-related stroke.

Methods

From the LAAO registry at The University of Kansas Medical Center, we identified patients who developed DRT. We chose 3 unmatched controls per DRT case from LAAO recipients without DRT. Predictor variables were obtained from transesophageal echocardiogram reports and/or images, transthoracic echocardiogram reports, and chart review. Implant depth was measured from the limbus of the left atrial ridge to the centre of the atrial aspect of the LAAO device, on a 45° transesophageal echocardiogram view.

Results

We identified 26 patients with DRT (aged 77.7 ± 9.7 years; 34.6% female) and selected 78 unmatched controls without DRT. Univariate predictors of DRT, comprising a novel TED-F2 score, included history of venous Thromboembolism (23.1% vs 5.1%, P = 0.01), an LAA Emptying velocity ≤ 20 cm/s (45.8% vs 18.9%, P = 0.01), an implant Depth > 2 cm (34.6% vs 12.8%, P = 0.02), and presence of AF rhythm at time of device implantation (50.0 % vs 11.5%, P = 0.0001). A TED-F2 score of ≥ 3 was very strongly associated with DRT-odds ratio 12.5 (95% confidence interval, 3.8-41.1, P < 0.0001).

Conclusions

We propose a novel risk score to predict development of DRT after LAAO, comprising history of venous Thromboembolism, LAA Emptying velocity ≤ 20 cm/s, implant Depth > 2 cm (1 point each), and an AF rhythm at implantation (2 points). A TED-F2 risk score of ≥ 3 identified patients who are at greatly elevated risk of developing DRT.

Impact of left atrial appendage occlusion device position on potential determinants of device-related thrombus: a patient-specific in silico study

BACKGROUND

Device-related thrombus (DRT) after left atrial appendage occlusion (LAAO) is potentially linked to adverse events. Although clinical reports suggest an effect of the device type and position on the DRT risk, in-depth studies of its mechanistic basis are needed. This in silico study aimed to assess the impact of the position of non-pacifier (Watchman) and pacifier (Amulet) LAAO devices on surrogate markers of DRT risk.

METHODS

The LAAO devices were modeled with precise geometry and virtually implanted in different positions into a patient-specific left atrium. Using computational fluid dynamics, the following values were quantified: residual blood, wall shear stress (WSS) and endothelial cell activation potential (ECAP).

RESULTS

In comparison to an ostium-fitted device position, deep implantation led to more residual blood, lower average WSS and higher ECAP surrounding the device, especially on the device's atrial surface and the surrounding tissue, suggesting increased risk for potential thrombus. For the non-pacifier device, an off-axis device orientation resulted in even more residual blood, higher ECAP and similar average WSS as compared to an ostium-fitted device position. Overall, the pacifier device showed less residual blood, higher average WSS and lower ECAP, compared to the non-pacifier device.

CONCLUSIONS

In this in silico study, both LAAO device type and implant position showed an impact on potential markers of DRT in terms of blood stasis, platelet adhesion and endothelial dysfunction. Our results present a mechanistic basis for clinically observed risk factors of DRT and the proposed in silico model may aid in the optimization of device development and procedural aspects.

Warfarin Therapy and Percutaneous Left Atrial Appendage Closure for a Patient with Atrial Fibrillation and Antithrombin-III Deficiency

Some patients develop ischemic stroke despite taking direct oral anticoagulants because of the presence of other risk factors such as coagulopathies. A 65-year-old male patient with non-valvular atrial fibrillation (NVAF) taking rivaroxaban was diagnosed as having embolic stroke and antithrombin-III (AT-III) deficiency. Echocardiography revealed a thrombus in the left atrial appendage (LAA). He was prescribed warfarin, and after resolution of the thrombus, we successfully performed percutaneous LAA closure (LAAC), with no subsequent recurrence or device-related thrombosis. Warfarin and LAAC may be feasible for NVAF patients with AT-III deficiency.

Catheter ablation for atrial fibrillation in patients with prior left atrial appendage occlusion device

BACKGROUND

The safety and efficacy of CA for AF and left-sided atrial arrhythmias (AA) in patients with left atrial appendage occlusion (LAAO) devices are lacking.

METHODS

This is a single-center retrospective registry that included all patients with prior LAAO who underwent catheter ablation for AF or left-sided atrial arrhythmia from January 2020-January 2023. The primary outcomes were procedure-related complications, device-related complications, AA recurrence, and stroke.

RESULTS

A total of 30 patients with prior LAAO were included in the analysis (mean age 75.1 ± 7.1 years old, 50% male, mean CHA2DS2-VASc score 4 ± 1.6, 46.7% paroxysmal AF, 73.3% had prior AF ablation, mean time to ablation 475 ± 365 days). 93.3% (n = 28) and 6.6% (n = 2) patients had ablation for AF (46.7% paroxysmal, 36.7% persistent, 10% long-standing persistent) and left-sided atrial tachycardia, respectively. 16.7% (n = 5) patients underwent ablation along the left atrial appendage ostium, and 3.3% (n = 1) underwent Vein of Marshall alcohol ablation. There were 3 (10%) peri-procedural complications (1 access hematoma and two pericardial effusions requiring intervention-none related to left atrial appendage ostium or alcohol ablation). During the mean follow-up of 440 ± 379 days, 40% (n = 12) patients had AA recurrence (91.6% AF, 8.3% atrial tachycardia), of which five patients needed repeat ablation, and two patients were readmitted for heart failure. There was no stroke or any device-related complications, including new peri-device leaks or device-related thrombosis in patients who had follow-up imaging studies (n = 11, 36.7%).

CONCLUSION

Catheter ablation for AF (including VoM alcohol ablation) in patients with prior LAAO devices is feasible and safe with favorable outcomes.

Late-onset left atrial appendage occlusion device-related thrombus attributed to mitral bioprosthetic stenosis: a case report

Background

Left atrial appendage occlusion (LAAO) is an alternative to anticoagulation for stroke prevention in select patients with atrial fibrillation (AF). In this study, we describe the case of a patient with delayed device-related thrombus (DRT) at 13 months post-LAAO in a setting of atrial stasis due to a worsening mitral bioprosthetic stenosis.

Case summary

A 69-year-old woman with a history of rheumatic mitral stenosis and regurgitation post-bioprosthetic mitral valve replacement (6 years prior) and paroxysmal AF was referred for percutaneous LAAO due to recurrent severe gastrointestinal bleeding while on anticoagulation. She underwent an uncomplicated LAAO, for which a 35 mm Watchman Flx device was used. Peri-procedural transoesophageal echocardiogram (TEE) at the time of implant showed thickened and calcified mitral bioprosthetic leaflets and a mild mitral stenosis. Her 45-day post-LAAO TEE showed a mild mitral stenosis and no peri-device leak or DRT. At 12 months, the patient had worsening exertional dyspnoea and pedal oedema. Her 12-month transthoracic echocardiogram (TTE) showed a moderate mitral stenosis and LAAO remained free of DRT. Her symptoms were deemed secondary from a worsening mitral valve stenosis. Mitral valve-in-valve (MViV) replacement was planned because the patient was deemed a prohibitive risk for a redo surgical replacement. Transthoracic echocardiogram on the day of MViV showed a large thrombus on the LAAO device. MViV was postponed. After the patient completed 45 days of anticoagulation with warfarin, a repeat TTE was performed, which showed a resolution of DRT. Transcatheter MViV was performed successfully.

Discussion

This case demonstrates that increased stasis and left atrial dysfunction from prosthetic mitral stenosis can be a risk factor for late DRT after successful LAAO. The use of a LAAO occlusion device in the presence of a mitral bioprosthesis requires more frequent echocardiographic monitoring to assess both the function of the prosthesis and a delayed formation of thrombus. More studies need to be conducted to assess the safety of percutaneous LAAO devices in those with mitral bioprosthesis.

Incidental Complication From a Left Atrial Appendage Device

This case report describes a diagnosis of extracardiac mural thrombus and pulmonary emboli resulting from a left atrial appendage device in a patient with atrial fibrillation.

Timely Transesophageal Echocardiography After Left Atrial Appendage Occlusion May Avoid Delayed Detection of Device-Related Thrombus

•Timely follow-up is critical in reducing the risk for device-related complications. •Studies are needed on the efficacy of DAPT after LAAO in high-risk patients. •Serial TEE is crucial for evaluating device-related complications. •Findings on TEE may be used to guide post-LAAO care.

Outcomes With the WATCHMAN FLX in Everyday Clinical Practice From the NCDR Left Atrial Appendage Occlusion Registry

BACKGROUND

PINNACLE FLX (Protection Against Embolism for Nonvalvular AF Patients: Investigational Device Evaluation of the WATCHMAN FLX LAA Closure Technology) demonstrated improved outcomes and low incidence of adverse events with the WATCHMAN FLX device in a controlled setting. The National Cardiovascular Disease Registry's Left Atrial Appendage Occlusion Registry was utilized to assess the safety and effectiveness of WATCHMAN FLX in contemporary clinical practice in the United States.

METHODS

The WATCHMAN FLX Device Surveillance Post Approval Analysis Plan used data from the Left Atrial Appendage Occlusion registry to identify patients undergoing WATCHMAN FLX implantation between August 2020 and September 2022. The key safety end point was defined as all-cause death, ischemic stroke, systemic embolism, or device or procedure-related events requiring open cardiac surgery or major endovascular intervention between device implantation and hospital discharge. Major adverse events were reported at hospital discharge, 45 days, and 1 year.

RESULTS

Among 97 185 patients in the Left Atrial Appendage Occlusion registry undergoing WATCHMAN FLX, successful implantation occurred in 97.5% (n=94 784) of patients. The key safety end point occurred in 0.45% of patients. At 45 days post-procedure, all-cause death occurred in 0.81% patients, ischemic stroke in 0.23%, major bleeding in 3.1%, pericardial effusion requiring intervention in 0.50%, device-related thrombus in 0.44%, and device embolism in 0.04% patients. No peri-device leak was observed in 83.1% of patients at 45 days. At 1 year, the rate of all-cause death was 8.2%, the rate of any stroke was 1.5% (ischemic stroke, 1.2%), and major bleeding occurred in 6.4% of patients.

CONCLUSIONS

In a large contemporary cohort of patients with the WATCHMAN FLX device, the rates of implant success and clinical outcomes through 1 year were comparable with the PINNACLE FLX study, demonstrating that favorable outcomes achieved in the pivotal approval study can be replicated in routine clinical practice.

Left Atrial Appendage Closure: A Single-Center Experience in a Population With a High Prevalence of End-Stage Renal Disease

Background Left atrial appendage closure (LAAC) has emerged as an alternative approach for mitigating thrombotic risk in nonvalvular atrial fibrillation patients. However, existing registries often lack representation of the Hispanic population, motivating this study to elucidate the demographic, clinical, and procedural characteristics, specifically among Hispanic patients undergoing this procedure. Methods Adult patients who underwent percutaneous LAAC between June 2017 and July 2022 at a high-complexity hospital in Bogotá, COL, were included. Baseline and procedural characteristics are reported. For patients with available follow-up data, major bleeding, thromboembolic events, and cardiovascular mortality were assessed. A subgroup analysis was conducted for patients with end-stage renal disease on dialysis. Results We included 33 patients. Follow-up data were available for 27 patients, with a mean follow-up period of 12.4 months. The median age of the cohort was 70 years (SD 9), with 58% being women. The median CHADS2 and HAS-BLED scores were 3 points (IQR 2 to 4) and 4 points (IQR 3 to 4), respectively. The 90-day cardiovascular mortality rate was 3.7%, whereas cardioembolic episodes and major bleeding events were reported at rates of 10.8 and 14.4 per 100 patient years, respectively. The long-term outcomes of patients on dialysis were comparable to those of nondialysis patients. Conclusions Our study reinforces existing evidence supporting the safety of LAAC, particularly in a multimorbid patient population with elevated bleeding and thrombotic risks. In this high-risk cohort, LAAC emerges as a feasible alternative for reducing thromboembolic risk. Notably, patients on dialysis demonstrated comparable long-term outcomes, suggesting the procedure's viability in this subgroup as well.

Left atrial appendage closure for stroke prevention in atrial fibrillation: current status and perspectives

Atrial fibrillation (AF) is associated with an increased risk of stroke and systemic embolism, and the left atrial appendage (LAA) has been identified as a principal source of thromboembolism in these patients. While oral anticoagulation is the current standard of care, LAA closure (LAAC) emerges as an alternative or complementary treatment approach to reduce the risk of stroke or systemic embolism in patients with AF. Moderate-sized randomized clinical studies have provided data for the efficacy and safety of catheter-based LAAC, largely compared with vitamin K antagonists. LAA device iterations, advances in pre- and peri-procedural imaging, and implantation techniques continue to increase the efficacy and safety of LAAC. More data about efficacy and safety of LAAC have been collected, and several randomized clinical trials are currently underway to compare LAAC with best medical care (including non-vitamin K antagonist oral anticoagulants) in different clinical settings. Surgical LAAC in patients with AF undergoing cardiac surgery reduced the risk of stroke on background of anticoagulation therapy in the LAAOS III study. In this review, we describe the rapidly evolving field of LAAC and discuss recent clinical data, ongoing studies, open questions, and current limitations of LAAC.

A comparison of simplified or conventional antithrombotic regimens after left atrial appendage closure in patients at high bleeding risk: the PLATEBRISK study

BACKGROUND

Antithrombotic treatment (ATT) post-left atrial appendage occlusion (LAAO) remains controversial. Furthermore, most of the patients undergoing LAAO are at a very high bleeding risk.

AIMS

This study aimed to compare a simplified versus conventional ATT after LAAO in very high bleeding risk patients.

METHODS

This is a multicentre, retrospective study including very high bleeding risk patients, according to the Bleeding Academic Research Consortium (BARC) definition, who underwent LAAO. These included patients at >4% risk of BARC 3 to 5 bleeding or >1% risk of intracranial bleeding after the procedure. Two groups were established based on the discharge ATT. The simplified group included single antiplatelet treatment or no treatment, and the conventional group comprised dual antiplatelet treatment or anticoagulation (combined or not with antiplatelet therapy).

RESULTS

A total of 1,135 patients were included. The mean CHA2DS2-VASc and HAS-BLED scores were 4.5±1.5 and 3.7±1.0, respectively. There were no differences in the composite endpoint (death, stroke, transient ischaemic attack, device-related thrombus or major bleeding) between the 2 groups (hazard ratio [HR] 0.81, 95% confidence interval [CI]: 0.59-1.11; p=0.188). Although the rate of major bleeding during the first year was numerically lower in the simplified group, it did not reach statistical significance (HR 0.67, 95% CI: 0.41-1.10; p=0.104). Nonetheless, patients with previous major bleeding presented a significantly lower rate of major bleeding when using the simplified treatment (HR 0.61, 95% CI: 0.36-0.99; p=0.049).

CONCLUSIONS

In patients with very high bleeding risk, a simplified ATT after LAAO seems to be as effective as conventional protocols. Furthermore, patients with a history of major bleeding experienced a lower risk of major bleeding with the simplified ATT.

Safety and effectiveness of left atrial appendage closure in atrial fibrillation patients with different types of heart failure

BACKGROUND

Both atrial fibrillation (AF) and heart failure (HF) are common cardiovascular diseases. If the two exist together, the risk of stroke, hospitalization for HF and all-cause death is increased. Currently, research on left atrial appendage closure (LAAC) in patients with AF and HF is limited and controversial. This study was designed to investigate the safety and effectiveness of LAAC in AF patients with different types of HF.

METHODS

Patients with non-valvular atrial fibrillation (NVAF) and HF who underwent LAAC in the First Affiliated Hospital of Army Medical University from August 2014 to July 2021 were enrolled. According to left ventricular ejection fraction (LVEF), the study divided into HF with reduced ejection fraction (LVEF < 50%, HFrEF) group and HF with preserved ejection fraction (LVEF ≥ 50%, HFpEF) group. The data we collected from patients included: gender, age, comorbid diseases, CHA2DS2-VASc score, HAS-BLED score, NT-proBNP level, residual shunt, cardiac catheterization results, occluder size, postoperative medication regimen, transthoracic echocardiography (TTE) results and transesophageal echocardiography (TEE) results, etc. Patients were followed up for stroke, bleeding, device related thrombus (DRT), pericardial tamponade, hospitalization for HF, and all-cause death within 2 years after surgery. Statistical methods were used to compare the differences in clinical outcome of LAAC in AF patients with different types of HF.

RESULTS

Overall, 288 NVAF patients with HF were enrolled in this study, including 142 males and 146 females. There were 74 patients in the HFrEF group and 214 patients in the HFpEF group. All patients successfully underwent LAAC. The CHA2DS2-VASc score and HAS-BLED score of HFrEF group were lower than those of HFpEF group. A total of 288 LAAC devices were implanted. The average diameter of the occluders was 27.2 ± 3.5 mm in the HFrEF group and 26.8 ± 3.3 mm in the HFpEF group, and there was no statistical difference between the two groups (P = 0.470). Also, there was no statistically significant difference in the occurrence of residual shunts between the two groups as detected by TEE after surgery (P = 0.341). LVEF was significantly higher in HFrEF group at 3 days, 3 months and 1 year after operation than before (P < 0.001). At 45-60 days after surgery, we found DRT in 9 patients and there were 4 patients (5.4%) in HFrEF group and 5 patients (2.3%) in HFpEF group, with no significant difference between the two groups (P = 0.357). One patient with DRT had stroke. The incidence of stroke was 11.1% in patients with DRT and 0.7% in patients without DRT (P = 0.670). There was one case of postoperative pericardial tamponade, which was improved by pericardiocentesis at 24 h after surgery in the HFpEF group, and there was no significant difference between the two groups (P = 1.000). During a mean follow-up period of 49.7 ± 22.4 months, there were no significant differences in the incidence of stroke, bleeding, DRT and HF exacerbation between the two groups. We found a statistical difference in the improvement of HF between HFrEF group and HFpEF group (P < 0.05).

CONCLUSIONS

LAAC is safe and effective in AF patients with different types of HF. The improvement of cardiac function after LAAC is more pronounced in HFrEF group than in HFpEF group.

Position Statement on Cardiac Computed Tomography Following Left Atrial Appendage Occlusion

Left atrial appendage occlusion (LAAO) is rapidly growing as valid stroke prevention therapy in atrial fibrillation. Cardiac imaging plays an instrumental role in preprocedural planning, procedural execution, and postprocedural follow-up. Recently, cardiac computed tomography (CCT) has made significant advancements, resulting in increasing use both preprocedurally and in outpatient follow-up. It provides a noninvasive, high-resolution alternative to the current standard, transesophageal echocardiography, and may display advantages in both the detection and characterization of device-specific complications, such as peridevice leak and device-related thrombosis. The implementation of CCT in the follow-up after LAAO has identified new findings such as hypoattenuated thickening on the atrial device surface and left atrial appendage contrast patency, which are not readily assessable on transesophageal echocardiography. Currently, there is a lack of standardization for acquisition and interpretation of images and consensus on definitions of essential findings on CCT in the postprocedural phase. This paper intends to provide a practical and standardized approach to both acquisition and interpretation of CCT after LAAO based on a comprehensive review of the literature and expert consensus among European and North American interventional and imaging specialists.

Watchman vs. Amulet for Left Atrial Appendage Closure: Current Evidence and Future Perspectives

Left atrial appendage closure (LAAC) is a crucial intervention for stroke prevention in patients with non-valvular atrial fibrillation who are unsuitable for long-term anticoagulation. Amulet and Watchman are the most implanted devices worldwide for performing LAAC, and the aim of this review is to provide a comprehensive comparison focusing on their efficacy, safety, and short- and long-term outcomes. The Watchman device, the first to gain FDA approval, has been extensively studied and demonstrates significant reductions in stroke and systemic embolism rates. The Amulet device, a newer alternative, promises enhanced design features for more efficient appendage sealing. Current data highlight that both devices offer similar efficacy and safety for LAAC. While the two devices differ in terms of intraprocedural complication rates, they offer similar short- to long-term outcomes in terms of peri-device leaks, device-related thrombosis, and mortality. Both devices are indicated for patients who are unable to tolerate OAC, given their similar risk and safety profiles. Newer clinical studies are directed at establishing the efficacy of both devices as the primary method for stroke prevention in AF as an alternative to OAC.

Thoracoscopic Left Atrial Appendage Occlusion with the AtriClip PRO2: An Experience of 144 Patients

AIM

To report the clinical outcomes of thoracoscopic left atrial appendage occlusion (LAAO) with the AtriClip PRO2 device (Atricure Inc, Mason, OH, USA). Stroke risk reduction with LAAO in patients with atrial fibrillation is now well-established. Many surgical and percutaneous techniques have been used, with varying rates of success. The percutaneous devices have had issues with procedural complications and peridevice flow. Thoracoscopic AtriClip offers an epicardial linear closure of the appendage at its ostium. This study sought to evaluate its safety and efficacy in achieving complete LAA closure.

METHOD

This is a prospective series of thoracoscopic AtriClip PRO2 as a standalone procedure or a thoracoscopic AtriClip deployed as an adjunct to minimal access cardiac and thoracic surgery. Study ethical approval was granted by the hospital Human Research Ethics Committee.

RESULTS

In total, 144 thoracoscopic AtriClip procedures were conducted by a single surgeon from 2017 to 2022, 56 standalone and 88 concomitant. There was no mortality or major morbidities. A 100% success in complete LAA closure was observed, with 87% complete follow-up imaging. For patients that underwent standalone AtriClip after cessation of anticoagulation, no thromboembolic phenomena were seen in the 180 patient-years of follow-up.

CONCLUSIONS

This study demonstrates that thoracoscopic placement of AtriClip is safe and effective in achieving consistent and complete LAAO. Future randomised trials will be useful to compare outcomes with percutaneous devices.

Transition from WATCHMAN generation-2.5 device to WATCHMAN FLX device for percutaneous left atrial appendage closure: Incidence and predictors of device-related thrombosis and short- to mid-term outcomes

BACKGROUND

Patients with nonvalvular atrial fibrillation (AF) not suitable for long-term anticoagulant therapy undergo percutaneous left atrial appendage closure (LAAC) using the WATCHMAN device. The safety and efficacy of WATCHMAN-FLX (WM-FLX) compared with WATCHMAN-2.5 (WM-2.5), particularly in Asian populations, is unknown.

METHODS

We evaluated the background, procedure, and clinical outcomes of 199 patients who underwent LAAC between September 2019 and December 2022 and compared WM-2.5 (72 patients) with WM-FLX (127 patients).

RESULTS

The mean age was 76 years, with 128 men, and 100 had nonparoxysmal AF (non-PAF). The mean CHA2DS2-VASc, and HAS-BLED were 5.1, and 3.2 points, respectively. WM-FLX group demonstrated a shorter procedure time than WM-2.5 group (50 vs. 42 min, p = 0.001). The WM-FLX group demonstrated no procedural-related acute cardiac tamponade, which was significantly low (5.6% vs. 0%, p = 0.02), and a significantly higher rate of complete seal at 45-day (63% vs. 80%, p = 0.04). WM-FLX group had a significantly higher cumulative 1-year incidence of device-related thrombosis (DRT) than WM-2.5 group (3.4% vs. 7.0%, Log-rank p = 0.01). Univariate analysis identified two DRT risk factors in the WM-FLX group: non-PAF (odds ratio [OR] 7.72; 95% confidence interval [CI] 1.20-48.7; p = 0.04), and 35-mm device (OR 5.13; 95% CI 1.31-19.8; p = 0.02).

CONCLUSIONS

WM-FLX significantly improved the procedural quality and safety of LAAC. However, DRT remains an important issue even in the novel LAAC device, being a hazard for patients with high DRT risk, such as having non-PAF and using 35-mm devices.