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The implantation of an occluder in the left atrial appendage (LAA) is an emerging therapy for the treatment of patients suffering from atrial fibrillation and with a contraindication to oral anticoagulation. The LAA occluder (LAAO) provides a reduction of the potential risk of strokes by thromboembolism. Currently, only a few CE-approved devices are available on the market and the number of clinical trials is comparatively low. Furthermore, there is currently no standardized test method available for testing functionality of the occluder, especially for testing safe anchorage and permeability. Therefore, the aim of this study is to establish an in vitro test method to prove anchorage mechanism and permeability regarding thromboembolism of the LAAO under physiological conditions. A standardized technical and fully parameterized silicone model of a LAA, based on studies of different morphologies and sizes, was developed. The LAA model was mounted onto the left atrial chamber of a commercial pulse duplicator system to simulate physiological hemodynamic conditions. The test was performed using the Watchman device (Boston Scientific, USA; size: 31 mm). The inner implantation diameter of the LAA model was designed according to a target compression of 10% for the Watchman device in the implanted configuration. Furthermore, thrombus-like particles (n=150, d=1,7±0,05 mm) were added to represent the flushing of thrombi out of the LAA after device implantation. Within several cycles it was confirmed that no particles were washed out of the LAA model with the implanted occluder leading to a full protection against thromboembolism. It could also be shown that the occluder is firmly anchored in the LAA. Pressure measurements with sensors in the left atrium and in the LAA distal to the occluder could also show that the occluder has no influence on the pressure conditions in the LAA.

Left atrial appendage occlusion (LAAO) has emerged as a valid alternative to oral anticoagulation therapy for the prevention of systemic embolism in patients with non-valvular atrial fibrillation (NVAF). Microvesicles (MVs) are shed-membrane particles generated during various cellular types activation/apoptosis that carry out diverse biological effects. LAA has been suspected to be a potential source of MVs during AF, but the effects its occlusion on circulating MVs levels are unknown. N = 25 LAAO and n = 25 control patients who underwent coronary angiography were included. Blood samples were drawn before and 48 h after procedure for all. A third sample was collected 6 weeks after procedure in LAAO patients. In N = 10 extra patients, samples were collected from right atrium, LAA and pulmonary vein during LAAO procedure. Circulating AnnV + procoagulant, endothelial, platelets, red blood cells/RBC and leukocytes derived-MVs were measured using flow cytometry methods. In the LAAO group, AnnV+, platelets, RBC, and leukocytes MVs were significantly increased following intervention, whereas only AnnV + MVs levels significantly rose in controls. The 6-w analysis showed that RBC-MVs and AnnV + MVs levels were still significantly elevated compared to baseline values in LAAO patients. The in-site analysis revealed that leukocytes and CD62e + endothelial-MVs were significantly higher in left atrial appendage compared to pulmonary vein, suggesting a local increased production. No major adverse event was observed in any patient post procedural course. LAAO impacts circulating MVs and might create mild pro-coagulant status and potential erythrocytes activation due to the device healing during the first weeks following intervention. • LAAO intervention creates a transient increase in platelets and leukocytes microvesicles. • AnnV+ and erythrocytes microvesicles are durably increased following LAAO. • Coagulation status and erythrocytes activation are modified during the first weeks following LAAO. [ABSTRACT FROM AUTHOR]

Endoluminal left atrial appendage occlusion is an emerging therapy to treat patients suffering from atrial fibrillation with contraindications against oral anticoagulation. Different occlusion devices have been introduced into the clinical setting while comparative studies between the devices are sparse. This in vitro study compares several endoluminal left atrial appendage occlusion systems regarding 2 mechanical properties: radial (RF) and tug force (TF). Seven different occluder systems of various sizes (24 in total) underwent testing throughout their recommended sizing range. RF was measured in a commercial RF tester. TF was assessed according to a recently published bench test. RF increased with compression of the devices: The LAmbre 2228 device exerted the highest RF (8.6 N) at maximum compression of 16 mm. The lowest RF of 0.1 N was exhibited by the 27 mm Occlutech occluder at minimal compression. The highest TFs were exerted by the WaveCrest devices at maximum compression with 4.6 and 3.6 N for the 22 mm and the 27 mm device, respectively. The lowest TFs were measured for the first‐generation Occlutech devices, particularly for the 24 mm device with 1.1 N at maximum compression and 0.4 N at minimum compression. A strong positive correlation was found between the number of hooks per millimeter circumference of an occluder and its tug force (r = 0.87, P < 0.01). The analysis revealed device stability to be more dependent on anchoring structures than on RF. The wide range of mechanical properties makes comparison of current LAA occluders difficult and emphasizes the need for standardized preclinical testing to prompt clinical compatibility. [ABSTRACT FROM AUTHOR]

This study sought to report the incidence, characteristics, and clinical impact of device-related thrombus (DRT) following left atrial appendage occlusion (LAAO) with the AMPLATZER Amulet device (Abbott, Plymouth, Minnesota). DRT is a potential serious complication of LAAO, but the incidence and clinical impact of DRTs in a real-world setting are not well characterized. A total of 1,088 patients were enrolled in a multicenter prospective study and followed for 1 year. All events were adjudicated by an independent committee, including the presence of DRT. Patients with DRT were reviewed for suboptimal device implantation and characterization of DRT formation. Multiple Cox regression was performed to identify predictors of DRT formation. Device implantation was successful in 1,078 (99%) patients, with 1-year follow-up completed in 96.3% of patients. A total of 18 DRTs occurred in 17 patients (1.7%/year), as a second DRT developed following complete resolution of an initial DRT in 1 patient. The left upper pulmonary vein ridge was not covered by the Amulet disc in 82% of DRT patients, indicating suboptimal implantation, with most thrombus developing in the untrabeculated area of the LAA ostium between the pulmonary vein ridge and the upper edge of the disc. Three (18%) DRT patients had an ischemic stroke, all within 3 months of DRT diagnosis. Patients with a DRT were at a greater risk for ischemic stroke or transient ischemic attack compared with non-DRT patients (hazard ratio: 5.27; 95% confidence interval: 1.58 to 17.55; p = 0.007). Larger LAA orifice width was a predictor of DRT formation (hazard ratio: 1.09; 95% confidence interval: 1.00 to 1.19; p = 0.04). Following LAAO with the AMPLATZER Amulet device, DRT was observed infrequently. Although the presence of DRT was associated with an increased rate of ischemic stroke or transient ischemic attack as compared with patients without DRT, the large majority of DRT patients (82%) did not experience any ischemic neurologic events. [ABSTRACT FROM AUTHOR]

Aim: Left atrial appendage occlusion (LAAO) is a technique for preventing thromboembolism in patients with atrial fibrillation and a high risk of irreversible bleeding. In some patients, a spontaneous iatrogenic transseptal leak (ITL) remains after LAAO. The aim of this study was to assess the correlation between ITL incidence and the results of cardiac function tests in patients who underwent LAAO.Methods and Results: LAOO was performed in 62 consecutive patients using the Amplatzer Amulet. Before and 3 months after LAA occlusion, the 6-min walking distance (6MWD) test was performed in all patients and oxygen consumption assessment (VO2max ) was performed in 32. All patients had transesophageal echocardiography before and 3 months after LAAO to assess ITL incidence. The patients were divided according to the presence and absence of ITL and the subgroup of patients with heart failure (HF) were further analyzed. In patients with HF and ITL, an increased VO2max (12.8 ± 5.2 vs 15.3 ± 4.7; P < 0.05) and 6MWD (350.1 ± 77.4 vs 414.3 ± 70.6; P < 0.05) was observed after the procedure comparing to the results before the procedure. The 6MWD was also significantly higher in the patients with transseptal leaks in comparison to those without (P < 0.0001).Conclusion: The presence of transseptal leaks after LAAO does not influence overall cardiac function test results. However, in patients with HF, there is an increase in oxygen consumption and 6MWD. These results indicate that ITLs in patients with HF decrease left atrial pressure, which is the key contributor to the symptoms of heart failure during physical activity. [ABSTRACT FROM AUTHOR]

The aim of this study was to establish in vitro bench-tests of left atrial appendage occlusion (LAAo) devices regarding tug force, radial force and sealing capacity. Two LAAo devices, namely the WATCHMAN™ and the Occlutech®, of three different sizes underwent testing in novel dedicated in vitro setups. Radial force was assessed in a commercial radial force tester. At baseline, tug force of the WATCHMAN™ was significantly higher when compared to Occlutech® for all devices. Repeated resheathing resulted in a reduction of device-diameter in the WATCHMAN™ devices of max. 7.9%, whereas diameters of Occlutech® occluders remained unchanged. Tug force was not significantly impacted by resheathing in both devices. At baseline, sealing capacity in a bench-test using silicone LAA-models did not differ between the devices. Resheathing lead to an in vitro loss of sealing capacity of the WATCHMAN™ devices, increasing with resheathing and resulting in a max. peridevice leak of 91.1 ± 7.9%. Radial force was higher for the Occlutech® devices and decreased for WATCHMAN™ occluders after resheathing. The WATCHMAN™ occluder series showed progressive deformation, increased peridevice leakage and decreased radial force after resheathing, presumably as a result of diameter reduction. Tug force of the WATCHMAN™ was not impaired by resheathing and was significantly higher than that of the Occlutech® device. [ABSTRACT FROM AUTHOR]

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Background Percutaneous mitral valve repair using MitraClip® (MC) is a well-established method for a subset of patients with severe mitral regurgitation (MR) and high risk for surgical intervention. Amplatzer® Cardiac Plug (ACP) occludes left atrial appendage and allows the discontinuation of oral anticoagulation and prevention of thromboembolic stroke. Due to the need for femoral and transseptal access in both procedures, a single approach could lead to minor risk of further complications and shorter cumulative intervention time. Methods We systematically analysed all four patients who underwent a combined procedure with MC and ACP in our heart-centre. All procedures were performed under fluoroscopic as well as echocardiographic guidance, and follow-up controls in a midterm period were carried out. Results In all patients (2 male/female; age 73–88 years), MC (1–2 Clips) and ACP (size 18-28 mm) were successfully implanted in one procedure (mean total time: 114 ± 17 min). At least moderate MR was achieved and two patients had no complications and therefore were discharged early. In a third patient, a dislocation of ACP occurred 2 h after the implantation. The oldest patient developed a respiratory insufficiency due to cardiac decompensation and further complications. Conclusion A combination of MC and ACP in a single procedure was feasible in this first case series of patients without a significant extension of procedure time. However, it might be important to select patients carefully. The location of optimal transseptal puncture may be challenging in regard to ACP placement, even in experienced hands and subsequent complications can occur. [ABSTRACT FROM AUTHOR]

Résumé La fibrillation atriale (FA) est le trouble du rythme le plus fréquent touchant l'adulte âgé et est associée à une augmentation du risque de décès, d'accident ischémique cérébral (AIC), d'insuffisance cardiaque ainsi qu'à une réduction de la qualité de la vie. La charge de cette pathologie sur le patient, les soignants, et donc le retentissement sociétal, est importante. La FA est une maladie chronique augmentant de façon significative le coût de la prise en charge qui peut être lié aux modalités initiales de prise en charge, au traitement des complications, ainsi qu'à la baisse d'activité professionnelle. Cependant, le coût exact de la prise en charge de cette complication, terme évolutif des cardiopathies, est difficile à définir. De nouvelles approches de traitement interventionnel de la FA sont donc proposées, qu'il s'agisse d'une ablation par cathéter ou de l'occlusion de l'auricule gauche afin de réduire le risque thromboembolique chez les patients ayant une contre-indication au traitement anticoagulant, qui réduit de façon significative le risque thromboembolique. Ces approches invasives sont cependant coûteuses. Cet article discute le coût de la prise en charge conventionnelle de la FA, contrôle du rythme vs contrôle de la fréquence cardiaque, ainsi que le coût de la prise en charge invasive, ablation vs traitement antiarythmique, occlusion vs traitement anticoagulant, et discutera en particulier les données comparatives évaluant le rapport coût/efficacité de ces différentes approches médicamenteuses ou interventionnelles souvent complémentaires et évolutives dans le temps. Atrial fibrillation (AF) is the most common arrhythmia encountered in adult and elderly population and is associated with increased risk of death, stroke, heart failure and reduced quality of life. It places an enormous burden on the patients, caregivers and the society at large. As a chronic illness, AF accrues significant costs related to clinical presentation, complications and loss of productivity. The exact economic burden of AF is difficult to define. Novel invasive approaches to AF aim to cure some patients (through catheter ablation) and/or induce a significant reduction in AF burden in others or to prevent complications such as thrombo-embolic events, but are very expensive (LAA occlusion, repeated catheter ablation). This review will address the cost of conventional (rhythm versus rate control) and invasive strategies in AF (ablation versus antiarrhythmic drugs, LAA occlusion) care and will review the evidence on the comparative cost effectiveness of these approaches. [ABSTRACT FROM AUTHOR]

Introduction: Atrial fibrillation (AF) is the most common clinically relevant arrhythmia and it is strongly associated with stroke. Left atrial appendage (LAA) is considered to be the most often source of thrombotic material. In recent decades a number surgical, percutaneous and hybrid approaches for LAA occlusion have been described revealing very different level of success and showing a variety of challenges associated with this matter. We present the first Polish experience with the stand-alone totally thoracoscopic LAA exclusion using novel clipping system. Material and methods: Four patients (one male) in mean age of 74 (± 13) years with long-standing persistent and chronic AF were admitted for totally thoracoscopic LAA exclusion. All patients had significant comorbidities and the history of the oral anticoagulation intolerance or suboptimal/unstable level (CHA2DS2-VASC > 5, HAS_BLED > 3). Three procedures were performed through totally thoracoscopic access. In one patient due to massive adhesions in the left pleura we performed minithoracotomy in fourth left intercostal space. In two months follow-up we observed no mortality, no strokes and no bleedings. Results: In all patient total exclusion of LAA with no residual remnant was confirmed. The "skin-to-skin" procedural time took on average 40, minimum 20 minutes. Patients were extubated directly or within two hours after procedure. All patients were discharged early in a good condition. Conclusions: Our initial first experience with the novel totally thoracoscopic clipping system for stand-alone LAA exclusion is very promising showing very high efficacy and good safety profile. [ABSTRACT FROM AUTHOR]

Non-Surgical Left Atrial Appendage Closure for Stroke Prevention in Atrial Fibrillation. The most feared complication associated with atrial fibrillation (AF) is stroke, the risk of which increases with advanced age. Because of its complex anatomy and diminished blood flow during AF, the left atrial appendage (LAA) has been a common site of left atrial thrombi and presumed source of thromboembolism. Systemic anticoagulation to treat what may be largely a localized phenomenon is associated with significant complications. Newer anticoagulation agents hold great promise in facilitating dosing and eliminating drug and food interactions, but do not eliminate bleeding risk. These challenges have led to interest in mechanical exclusion of the LAA as a means of preventing thromboembolism in AF. Although surgery permits greater visualization and management of complications, the potential morbidity has limited adoption in often-frail elderly patients. In this paper, we review the current state of percutaneous left atrial exclusion for stroke prevention in AF, and the strengths and limitations of each of these strategies. The nonsurgical approaches to excluding the LAA from the central circulation can be divided into 3 broad categories: transseptally placed devices, percutaneous epicardial approach, and hybrid approaches. The availability of several approaches will allow physician selection of the optimal approach for a given patient based on clinical, physiological, and anatomical considerations. LAA exclusion stands to become an increasingly attractive option for patients with nonvalvular AF because it can be offered to elderly AF patients, and eliminates the long-term cumulative bleeding risks and adherence challenge of anticoagulants. (J Cardiovasc Electrophysiol, Vol. 22, pp. 1179-1180, October 2011) [ABSTRACT FROM AUTHOR]

A stroke attack in the brainstem area as a serious complication of atrial fibrillation (AF) in a 51 year old woman with known paroxysmal AF (CHADS² score 3) was treated with LAA occlusion procedure after the complication of arterial bleeding secondary to anticoagulation therapy. LAA closure device embolisation was developed following the LAA occlusion procedure. The device was located and removed successfully from the systemic circulation.

Patients with atrial fibrillation are at increased risk of stroke, and the addition of a single risk factor indicates a need for prophylaxis with warfarin or a non-VKA oral anticoagulant. Left atrial appendage occlusion is a potential alternative if long-term anticoagulation is contraindicated. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 pandemic is having a major impact on healthcare systems worldwide. Several months after the COVID-19 outbreak, waiting lists of non-urgent structural heart (SH) interventions continue to increase. Limitations in terms of ICU beds and anesthesiology represent a major limitation to conduct non-urgent SH interventions and are a valid reason to move towards less invasive approaches. The field of left atrial appendage occlusion (LAAO) reflects this challenging situation perfectly. The aim of this paper is to describe the possibilities for pre-procedural LAA assessment, performance of the LAAO procedure and post-procedural surveillance in these challenging times., (Published on behalf of the European Society of Cardiology. © The Author(s) 2020.)

Preoperative assessment with computed tomography (CT) is critical before transcatheter interventions for structural heart disease. CT provides information for device selection, device sizing, and vascular access approach. The interpreting radiologist must have knowledge of appropriate CT protocols, how and where to obtain the important measurements, and know additional imaging characteristics that are important to describe for optimal support of the interventionalist. CT is the modality of choice for pre-operative evaluation in patients undergoing transcatheter aortic valve replacement and left atrial appendage occlusion, and is also useful before transcatheter mitral valve replacement, which is an ongoing area of research., Competing Interests: Disclosure The authors have nothing to disclose., (Copyright © 2020 Elsevier Inc. All rights reserved.)

In this article, most of the present or available in the near future left atrial appendage (LAA) occlusion devices are discussed in terms of structure of the devices and principle technique for implantation. Thus, the Watchman™ device from Boston, the Amulet™ device from Abbot, the Lambre™ device from Lifetech, the Occlutech® device from Occlutech®, and the WaveCrest® device from Biosense Webster (former Coherex) are discussed. The systems differ in terms of the concept of occlusion. Several devices consist of only one part (Watchman™ and Occlutech®) that is implanted in the body, ending up in the orifice of the LAA. Others like the Amulet™ or Lambre™ device have an additional disc covering the orifice of the LAA from the left atrial side. The distal anchoring system is implanted first in the body of the LAA; thereafter, the disc is placed upon the orifice. With the WaveCrest® device, covering of the orifice is performed as the first step followed by rolling in the anchoring system to fix the device to the body of the LAA.

ABSTRACT:A stroke attack in the brainstem area as a serious complication of atrial fibrillation (AF) in a 51 year old woman with known paroxysmal AF (CHADS2score 3) was treated with LAA occlusion procedure after the complication of arterial bleeding secondary to anticoagulation therapy. LAA closure deviceembolisation was developed following the LAA occlusion procedure. The device was located and removed successfully from the systemic circulation. [ABSTRACT FROM AUTHOR]

A stroke attack in the brainstem area as a serious complication of atrial fibrillation (AF) in a 51 year old woman with known paroxysmal AF (CHADS(2) score 3) was treated with LAA occlusion procedure after the complication of arterial bleeding secondary to anticoagulation therapy. LAA closure device embolisation was developed following the LAA occlusion procedure. The device was located and removed successfully from the systemic circulation.