Peridevice Leak After Left Atrial Appendage Occlusion: Incidence, Mechanisms, Clinical Impact, and Management

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 anatomy: clinical implications for cardiac procedures

The Left Atrial Appendage (LAA) is the most common source of thrombi during atrial fibrillation (AF) leading to stroke. With the increasing prevalence of AF and the growing number of patients requiring LAA involved interventions like exclusion and ablation, understanding LAA's anatomical intricacies becomes paramount importance. This study aims to provide anatomical data regarding LAA in relation to these procedures. Total 50 formalin-fixed cadaveric hearts were examined and various morphological and morphometric parameters were noted. The Cauliflower shape LAA (36%) was most common followed by Chicken Wing (34%), Cactus (18%), and Windsock (12%) shapes. The LAA orifice had greater horizontal diameter compared to the vertical diameter and was oval in shape in 64% cases. Diverticular structures called divots/ pits were present surrounding the LAA orifice in 36% cases with high variation in number, size, and distance from orifice. They were most commonly present towards the septal side and posterior wall side around the LAA orifice. The circumflex artery was the closest structure to LAA orifice with less than 5 mm distance in 76% cases. Other structures present close to the LAA were the Left Superior Pulmonary Vein and Mitral Valve. According to shape, the Non-Chicken Wing morphology of the LAA was associated with close running left circumflex artery, high OI (Ovality Index) of the orifice, and greater presence of divots. The LAA anatomy is complex with high amount of variability making it difficult to perform successful procedures. Given data can help clinicians in better planning and execution of cardiac interventions involving the LAA.

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.

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.

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.

Pulmonary Ridge Coverage: a Two-edged Sword in Left Atrial Appendage Closure With LAmbre

BACKGROUND

The LAmbre occluder, available in 2 versions, allows for selective coverage of the pulmonary ridge (PR) during left atrial appendage closure (LAAC). In this study we evaluated the effects of PR coverage on imaging and clinical outcomes in patients undergoing LAAC.

METHODS

Imaging data and clinical events were retrospectively analyzed for patients with nonvalvular atrial fibrillation who successfully underwent LAAC using the LAmbre device at the First Affiliated Hospital of Wenzhou Medical University between October 2018 and May 2022. The primary composite endpoint was thromboembolic (TE) events and device-related thrombus (DRT).

RESULTS

In total, 259 patients were evaluated using transesophageal echocardiography (TEE) at median intervals of 52 days (short term) and 385 days (long term). Patients were divided into a PR-covered group (n = 109) and a PR-uncovered group (n = 150). PR-uncovered patients showed a trend toward higher DRT incidence (8 of 150 vs 1 of 109, P = 0.056, log-rank test). The primary composite endpoint of TE events and DRT was significantly lower in the PR-covered group (14.0% vs 6.4%, P = 0.046, log-rank test). Any peridevice leak (PDL) was more frequent in the PR-covered group during both short-term (45.9% vs 28.7%, P = 0.004) and long-term (49.5% vs 25.3%, P < 0.001) follow-up, but no differences were observed for significant PDLs (> 3 mm). PR coverage was identified as an independent predictor of any long-term PDL (odds ratio 3.19, 95% confidence interval 1.64-6.18, P < 0.001).

CONCLUSIONS

PR coverage during LAAC with the LAmbre device was associated with a reduced risk of the primary composite endpoint of TE events and DRT, albeit with an increased incidence of nonsignificant PDL (≤ 3 mm).

Short- and long-term outcomes of percutaneous left atrial appendage occlusion in cancer patients

Introduction and objectives

Percutaneous left atrial appendage occlusion (LAAO) is a viable option to mitigate bleeding and stroke risks in patients with atrial fibrillation (AF) who are not eligible for oral anticoagulation. Its safety and efficacy in cancer patients remain unclear due to their exclusion from trials. This study aimed to compare short- and long-term LAAO outcomes between cancer and non-cancer patients.

Methods

Retrospective single centre study of 361 consecutive patients who underwent LAAO between april-2010 and december-2023 were included. Short-term outcomes included periprocedural complications, 30-day hospital readmission and mortality. Long-term outcomes included the composite of stroke, bleeding, and mortality and each component assessed separately.

Results

The study included 93 cancer patients (54 % active, 46 % in remission) and 268 non-cancer patients. Baseline characteristics were similar, including ischemic and bleeding risk profiles (CHA2DS2-VASc: 4.5 ± 1.4 vs. 4.4 ± 1.5; HAS-BLED: 3.3 ± 0.9 vs. 3.2 ± 0.9), previous stroke and total bleeding events. Short-term outcomes showed no significant differences in periprocedural complications (7 % vs. 6 %), 30-day readmission (2 % vs. 3 %), or 30-day mortality (0 % vs. 1.5 %). Over 32 months, there was no significant difference regarding the composite endpoint (p = 0.067), stroke (SHR 0.54; p = 0.25) or bleeding events (SHR 1.36; p = 0.35). LAAO was effective in terms of stroke reduction in cancer and non-cancer patients (p = 0.027 and p = 0.006, respectively). All-cause mortality rates were higher in cancer patients (p = 0.002), mainly due to cancer progression and infections.

Conclusions

LAAO procedure was safe and effective in both populations. Cancer patients experienced higher rates of all-cause mortality, with no differences in stroke and bleeding outcomes between groups.

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.

Left atrial appendage occlusion: trends in demographics and in-hospital outcomes-a German nationwide analysis

BACKGROUND

LAAO is an interventional, prophylactic treatment to prevent cardioembolic stroke in patients with non-valvular atrial fibrillation.

AIMS

The aim of this study was to assess gender differences and age-related in-hospital course of all patients undergoing left atrial appendage occlusion (LAAO) in Germany.

METHODS

The Research Data Center of the Federal Statistical Office accessed interrogation of its Diagnosis Related Groups (DRG) statistics database. In a retrospective observational manner, all German in-hospital cases from 2016 to 2022 with a coded LAAO procedure were analyzed.

RESULTS

LAAO was performed on a total of 40,435 patients, 39.2% of whom were female. The relative frequency of procedures in the German male population over the age of 60 was twice as high as in the German female population. The median age was 78 (IQR: 72-82) years. Compared to 28.3% in 2016, in 2022 40.1% of all patients were over 80 years of age (increased by 152%). Cases of patients over 85 years of age increased from 7.7 to 11.4% during the same time period. We found an in-hospital death rate for patients < 70, 70-75, 80-85 and > 85 years of age of 0.8, 1.0, 1.4 and 2.2% respectively. Further, we saw significantly higher MACE rates (< 75 years: 4%, 75-85 years: 5%, > 85 years: 7%) in patients with a higher age. Gender was not significantly associated with a higher rate of in-hospital mortality.

CONCLUSIONS

In Germany, LAAO is increasingly performed in older patients with a strong gender imbalance. Age was independently associated with higher in-hospital MACE and mortality rates. This data provides a further basis to balance risks and benefits of LAAO as a preventive procedure and highlights the need for further prospective studies.

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.

Reproducibility of cardiac computed tomography classifications of hypoattenuated thickening and peridevice leak following left atrial appendage closure

AIMS

To assess the reproducibility of interpreting hypoattenuated thickening (HAT) and peridevice leak (PDL) using cardiac computed tomography (CT) imaging following Watchman FLX left atrial appendage closure (LAAC).

METHODS AND RESULTS

In this multicentre retrospective reproducibility study, 100 anonymized post-LAAC cardiac CT scans were evaluated within the same cardiac phase by an experienced and a novice rater blinded to prior evaluations. All scans were evaluated twice by each rater, assessing overall HAT and PDL categories as well as specific associated findings based on suggested algorithms for post-LAAC interpretation. Inter- and intra-rater agreement and reliability were evaluated using absolute agreement, Cohen's kappa, and Kendall's tau for categorical variables, and mean difference, Bland-Altman plots, limits of agreement (lower and upper), and intra-class correlation coefficients (ICCs) for continuous variables. Within overall categories of both HAT and PDL, substantial agreement (kappa ≥0.61) and reliability (Kendall's tau-b ≥ 0.75) were observed. Specifically, identifying high-grade HAT (kappa ≥0.78) and distal patency (kappa ≥0.85) displayed the highest agreement within HAT and PDL interpretation. Meanwhile, measuring the height of the proximal screw hub cove represented the least reliable HAT assessment among both inter- and intra-rater comparisons (ICC < 0.75), while suspected leak mechanism represented the least reproducible PDL measure.

CONCLUSION

Despite only minimal training of one rater, overall high levels of inter- and intra-rater agreement and reliability were observed across the chosen algorithms for interpretation of HAT and PDL following Watchman FLX LAAC. The prognostic implications of the included variables are to be explored in future trials and registries.

Combined left atrial appendage occlusion and catheter ablation procedure for left atrial arrhythmias: A real-world, propensity-matched analysis

INTRODUCTION

Real-world studies comparing safety and efficacy of combined percutaneous left atrial appendage occlusion (LAAO) and catheter ablation (CA) to LAAO alone are limited.

METHODS

Patients from a large US hospital system undergoing combined LAAO and left-atrial CA from 8/2020 to 2/2024 were retrospectively analyzed and compared to a control group undergoing LAAO alone. Controls were identified using a 1:2 propensity score match based on LAAO device type (Watchman FLX vs. Amulet), CHA2D2-VASc and Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile international normalized ratio [INR], Elderly, Drugs/alcohol (HAS-BLED) scores and compared for safety, sealing performance and clinical outcomes at 6 months.

RESULTS

Patients were younger in the combined (n = 72) than in the control group (n = 144, 70.2 ± 7.3 vs. 76.7 ± 6.9 years, p < 0.001) but otherwise comparable with a mean CHA2D2-VASc score of 4.2 ± 1.1 and 4.4 ± 1.2 (p = 0.26) and HAS-BLED score of 2.2 ± 0.8 and 2.3 ± 0.7 (p = 0.34). Successful LAAO implantation rates were the same (95.8% vs. 95.8%, p = 0.99) with longer procedure times seen in the combined group (156.5 ± 53 vs. 56 ± 26 min, p < 0.001). Both major (1.4% vs. 2.1%, p = 0.72) and minor (27.8% vs. 19.4%, p = 0.17) in-hospital complications were similar between the combined and control group, respectively. At 45 days, presence of peri-device leak (18.3% vs. 30.4%, p = 0.07) and device related thrombosis (4.5% vs. 4.5%, p = 0.96) on transesophageal echocardiogram did not differ. Finally, all-cause mortality (0% vs. 1.4%, p = 0.99), thromboembolic (0% vs. 0%, p = 0.99) and bleeding (6.1% vs. 4.4%, p = 0.73) events during follow-up were comparable.

CONCLUSION

This large, real-world analysis indicates comparable safety and efficiency of combined LAAO and CA when compared with LAAO alone.

Transcatheter Structural Heart Disease Interventions and Concomitant Left Atrial Appendage Occlusion: A State of the Art Review

Atrial fibrillation (AF) is the most common arrhythmia in patients with valvular heart disease, and it can be associated with adverse patient outcomes. However, the need for anticoagulation to counterbalance AF-associated stroke risk may further lead to suboptimal outcomes via increasing bleeding events, especially in high-risk individuals. Because the vast majority of thrombi occur in the left atrial appendage, left atrial appendage occlusion (LAAO) is an established procedure for preventing ischemic stroke in patients with AF, while limiting anticoagulation-related bleeding events. Thus, the concept of combining an index procedure for structural heart disease (SHD) with LAAO seems promising for preventing future stroke events. A combined procedure has been described in aortic stenosis (transcatheter aortic valve implantation + LAAO), mitral regurgitation (transcatheter edge-to-edge repair + LAAO), and atrial septal defects (patent foramen ovale/atrial septal defect + LAAO). Evidence shows that a combined procedure can be safely performed in a "1-stop shop" fashion, without increased rates of procedural adverse events, with the potential to limit bleeding risk and provide prophylaxis against stroke events. This review analyses indications and clinical evidence regarding the safety and efficacy of combined SHD+LAAO procedures, while also providing insights into gaps in knowledge and future directions for the evolution of this field.

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.

Incidence and temporal evolution of delayed peridevice leak after left atrial appendage closure

BACKGROUND

Peridevice leak (PDL) after left atrial appendage closure (LAAC) portends adverse outcomes.

OBJECTIVE

The purpose of this study was to assess the incidence, predictors, clinical implications, and temporal evolution of PDL after LAAC.

METHODS

This single-center retrospective study included all patients who underwent LAAC with Watchman FLX and had no PDL detected at the time of implantation. The primary end point was the incidence of new PDL at initial imaging. The composite secondary end point included continued oral anticoagulation after initial imaging, device-related thrombus, stroke or transient ischemic attack, major bleeding, and need for PDL closure at longest follow-up. Temporal evolution of PDL was assessed in patients with available surveillance imaging.

RESULTS

Of the 355 patients who completed imaging at 47 days (interquartile range [IQR] 44-50 days), 139 (39%) had new PDL with a mean leak size of 3.2 ± 1.4 mm (median 3.0 mm; IQR 2.0-4.0 mm; range 1.0-9.0 mm). Multiple deployment attempts and larger device size were positive predictors of PDL, while increased contrast volume administration was a negative predictor of PDL. The composite secondary end point occurred in 42 (30%) patients with PDL and 33 (15%) patients without PDL (P < .001). Of the 139 patients with PDL, 43 (31%) had surveillance imaging where the leak size regressed from 3.7 ± 1.8 mm at 46 days (IQR 44-51 days) to 1.7 ± 2.0 mm at 189 days (IQR 158-285 days) (P < .001). The leak size regressed in 33 (77%), remained stable in 4 (9%), and progressed in 6 (14%) cases.

CONCLUSION

Despite design improvements, LAAC with Watchman FLX demonstrates a significant incidence of PDL with meaningful clinical implications. Regardless of initial size, most leaks regressed over time.

Impact of occluder device configurations in in-silico left atrial hemodynamics for the analysis of device-related thrombus

Left atrial appendage occlusion devices (LAAO) are a feasible alternative for non-valvular atrial fibrillation (AF) patients at high risk of thromboembolic stroke and contraindication to antithrombotic therapies. However, optimal LAAO device configurations (i.e., size, type, location) remain unstandardized due to the large anatomical variability of the left atrial appendage (LAA) morphology, leading to a 4-6% incidence of device-related thrombus (DRT). In-silico simulations have the potential to assess DRT risk and identify the key factors, such as suboptimal device positioning. This work presents fluid simulation results computed on 20 patient-specific left atrial geometries, analysing different commercially available LAAO occluders, including plug-type and pacifier-type devices. In addition, we explored two distinct device positions: 1) the real post-LAAO intervention configuration derived from follow-up imaging; and 2) one covering the pulmonary ridge if it was not achieved during the implantation (13 out of 20). In total, 33 different configurations were analysed. In-silico indices indicating high risk of DRT (e.g., low blood flow velocities and flow complexity around the device) were combined with particle deposition analysis based on a discrete phase model. The obtained results revealed that covering the pulmonary ridge with the LAAO device may be one of the key factors to prevent DRT, resulting in higher velocities and reduced flow recirculations (e.g., mean velocities of 0.183 ± 0.12 m/s and 0.236 ± 0.16 m/s for uncovered versus covered positions in DRT patients). Moreover, disk-based devices exhibited enhanced adaptability to various LAA morphologies and, generally, demonstrated a lower risk of abnormal events after LAAO implantation.

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.

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.

Long-term cardiac computed tomography follow-up after left atrial appendage occlusion

BACKGROUND

Left atrial appendage occlusion (LAAO) is performed increasingly, but long-term follow-up imaging data are lacking.

AIMS

The aim of this study was to evaluate the safety and durability of the Amplatzer Amulet device >4 years after LAAO.

METHODS

This was a prospective observational cohort study including 52 patients implanted with the Amplatzer Amulet device at Aarhus University Hospital, Denmark. A >4-year follow-up cardiac computed tomography (CT) scan after LAAO was performed and compared with the results from the 2-month and 12-month scans. The primary outcome was left atrial appendage (LAA) sealing based on distal LAA contrast patency and peridevice leakage (PDL), stratified into complete occlusion (grade 0 [G0]) and grade 1-3 leakage (G1-3), respectively. Secondary outcomes were low- and high-grade hypoattenuated thickening (HAT), device-related thrombosis (DRT) and device durability.

RESULTS

The median (interquartile range [IQR]) follow-up time from LAAO to the latest CT scan was 5.8 years (4.5; 6.3). At 2-month (n=52), 12-month (n=27) and >4-year CT follow-ups (n=52), rates of both complete occlusion (33%, 37%, 35%) and G2 leaks (52%, 52%, 48%) remained stable. Rates of G1 leaks varied (14%, 4%, 6%) and G3 leaks rose (2%, 7%, 12%) from earliest to latest follow-up. The median left atrial (LA) volume increased from 127 mL (96; 176) to 144 mL (108; 182) and 147 mL (107; 193). No DRT was found. The structural device integrity was preserved.

CONCLUSIONS

This study indicates a stable LAA sealing status throughout the follow-up period, emphasising the importance of the procedural result in avoiding PDL. Few patients displayed PDL progression, which might partly be related to LA remodelling with increasing volume. The long-term device durability appears excellent. Larger studies are warranted to confirm these findings.

Computed tomography-based device-sizing in Amplatzer Amulet left atrial appendage occlusion

BACKGROUND

Amplatzer Amulet is a frequently used device for left atrial appendage occlusion (LAAO). The current sizing protocol is based on the maximum diameter of the left atrial appendage (LAA) landing zone. However, mean, perimeter-, or area-derived diameter might be more accurate measures for device sizing.

METHODS

Retrospective analysis of 150 consecutive patients undergoing LAAO is guided by pre-procedural cardiac CT. A total of 117 patients were included; 7 were excluded due to renal failure and 26 due to closure with the sandwich technique. The maximum, mean, area-, and perimeter-derived diameters of the landing zone were derived from pre-procedural cardiac CT scans, and their accuracy to predict the implanted device size was investigated. The predicted device size was determined based on the currently recommended sizing algorithm. Peri-device leak (PDL) was assessed (grade 1-3) along with the underlying mechanism.

RESULTS

Device-sizing accuracy was superior for mean, area-, and perimeter derived diameters compared with the maximal diameter, especially for eccentric landing zones. Mean difference between predicted and actually implanted device size was 0.08 mm (± 2.77), 0.30 mm (± 2.40), - 0.39 mm (± 2.43), and - 2.55 mm (± 2.57) across mean, area-derived, perimeter-derived, and maximal diameter, respectively. Grade 3 peri-device leak was seen in 8.5% of implants without a significant association to the eccentricity of the landing zone. The leading mechanism for PDL was device malalignment.

CONCLUSION

Our results indicate mean, area-, and perimeter-derived diameters of the device landing zone to perform similar and superior in device-sizing accuracy compared with the maximum diameter.

Impact of left atrial appendage orifice diameter on the safety and efficacy of left atrial appendage closure using the LAmbre device

BACKGROUND

The diameter and shape of the left atrial appendage (LAA) orifices may influence occluder selection and the outcomes of left atrial appendage closure (LAAC) procedure. This study aimed to evaluate the impact of LAA orifice diameter on the safety and efficacy of LAAC using the LAmbre device.

METHODS

A total of 133 patients with nonvalvular atrial fibrillation (AF) who underwent LAAC with the LAmbre device between June 2018 and June 2020 were included in this study. The patients were categorized into two groups based on the maximal diameter of the LAA orifice: the large LAA group (n = 45) with a maximal orifice diameter of ≥31 mm, and the normal LAA group (n = 88) with a maximal orifice diameter of <31 mm. The study assessed periprocedural characteristics and long-term clinical follow-up.

RESULTS

Successful implantation of the LAmbre device was observed in all patients. The incidence of periprocedural peridevice leakage (PDL) was significantly higher in the large LAA group (P < 0.001), while the incidence of acute pericardial effusion (PE) during the procedure was comparable between the two groups (P = 1.000). After a mean follow-up period of 4.8 ± 1.7 years, three patients in the large LAA group developed delayed PE, while no patients in the normal LAA group did (P = 0.037). Additionally, a larger LAA maximal orifice diameter was associated with a higher prevalence of PDL (P = 0.001) and PE (including both acute and delayed PE) (P = 0.027). The optimal cutoff value of the LAA maximal orifice diameter for predicting PDL and PE after LAAC with the LAmbre device was determined to be 30 mm.

CONCLUSION

The findings suggest that the LAmbre device is a safe and feasible option for occluding the LAA, regardless of its orifice diameter. However, it is important to note that a larger LAA orifice diameter may increase the risk of PDL and delayed PE.

Cardiac computed tomography angiography for assessment of endothelial insufficiency of left atrial appendage disc-like occluder

INTRODUCTION

This study was performed to explore the diagnostic value of cardiac computed tomography angiography (CCTA) for endothelial insufficiency (EIS) of a left atrial appendage (LAA) disc-like occluder.

METHODS

Fifty-nine patients with nonvalvular atrial fibrillation who underwent placement of an LAA disc-like occluder (LAmbre; Lifetech Scientific) in our hospital were retrospectively analyzed. Patients who were found to have contrast agent entering the LAA at the 3-month postoperative CCTA examination underwent Hounsfield unit (HU) measurement of the LAA and construction of a three-dimensional (3D) model of the device for preliminary discernment between peri-device leakage (PDL) and EIS. These patients were then further examined by transesophageal echocardiography (TEE) to check for concordance with the computed tomography (CT) findings. According to the CT and TEE results, all patients were divided into the PDL group, total endothelialization group, and EIS group. The endothelial conditions and other implantation-related results were also tracked at the 6-month follow-up.

RESULTS

All 59 patients underwent successful implantation of the LAmbre LAA closure device with no severe adverse events during the procedure. Thirty-five patients were found to have contrast agent entering the LAA at the 3-month postoperative CCTA follow-up. Based on the CT HU measurement and the 3D construction analysis results, these 35 patients were divided into the PDL group (19 patients) and the EIS group (16 patients). In the PDL group, the contrast agent infiltrated from the shoulder along the periphery of the occluder on two-dimensional (2D) CT images, and the 3D model showed a gap between the LAA and the device cover. However, the CCTA images of the other 16 patients in the EIS group showed that the contrast agent in the occluder on the 2D CTA images and 3D construction model confirmed the absence of a gap between the LAA and the device cover. TEE confirmed all of the CT results. The 6-month follow-up results showed that 14 of 19 patients in the EIS group achieved total endothelialization, whereas this number in the PDL group was only five of 19 patients.

CONCLUSION

CCTA can replace TEE for examination of the endothelialization status, and patients with EIS have a higher chance of endothelialization than patients with PDL.

Device-Related Thrombus After Left Atrial Appendage Occlusion: Clinical Impact, Predictors, Classification, and Management

Despite the unprecedented advances in the left atrial appendage occlusion field, device-related thrombus (DRT) remains an unresolved issue with the therapy. This paper aims to provide a state-of-the-art review of the literature on the incidence, clinical impact, predictors and management of DRT and propose a novel classification of DRT and hypoattenuated thickening.