Left Atrial Appendage Occlusion Devices Research Articles

Mechanical Performance of Two Left Atrial Appendage Occlusion Systems: In Vitro Comparison of Tug Force, Radial Force, Sealing and Deformation.

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.

Percutaneous Closure of Left Atrial Appendage significantly affects Lipidome Metabolism

Patients with non-valvular atrial fibrillation (AF) and a high risk for oral anticoagulation can be treated by percutaneous implantation of left atrial appendage occlusion devices (LAAC) to reduce the risk of cardio-embolic stroke. This study evaluates whether LAAC may influence lipid metabolism, which has never been investigated before. Patients with successful LAAC were included consecutively. Venous peripheral blood samples of patients were collected immediately before (T0, baseline) and 6 months after (T1, mid-term) LAAC. A targeted metabolomics approach based on electrospray ionization liquid chromatography–mass spectrometry (ESI-LC-MS/MS) and MS/MS measurements was performed. A total of 34 lipids revealed a significant change from baseline to mid-term follow-up after successful LAAC. Subgroup analysis revealed confounding influence by gender, age, diabetes mellitus type II, body mass index, left ventricular ejection fraction, creatinine and NT-proBNP. After multivariable adjustment within logistic regression models, these 34 lipids were still significantly altered after LAAC. Successful percutaneous LAAC may affect lipid metabolism and thereby may potentially affect pro-atherogenic and cardio-toxic effects.

Left Atrial Appendage Occlusion: What Are the Options and Where is the Evidence?

Left atrial appendage occlusion (LAAO) has emerged as an effective site-directed therapy in patients with nonvalvular atrial fibrillation (AF) for stroke prevention, who are ineligible for long-term oral anticoagulation. The objective of this study was to assess the safety, efficacy, and availability of LAAO devices by reviewing the literature and to review the development and effectiveness of LAAO by the transcatheter approach with plugging devices such as WATCHMAN™ (Boston Scientific, Natick, MA, USA); AMPLATZER™ Cardiac Plug and AMPLATZER™ Amulet™ (Abbott Laboratories, Chicago, IL, USA); and the LARIAT® Suture Delivery Device (SentreHEART, Redwood City, CA, USA), which features an entirely unique hybrid (endocardial and epicardial) approach in closing the left atrial appendage (LAA). The conducted literature review ultimately revealed a substantial body of literature supporting the safety and efficacy of various LAAO strategies, including endocardial, epicardial, and hybrid approaches, in AF patients who are not eligible for long-term oral anticoagulant use. Specifically, the most attractive population suitable for LAA closure appears to be patients at high risk for ischemic stroke with a longer life expectancy but a moderate-to-high bleeding risk with long-term oral anticoagulation. The benefit of LAA closure in reducing the incidence of stroke in patients with nonvalvular AF has been evolving gradually, and we are confident that this new field of percutaneous LAA closure will continue to emerge as a game-changer in the treatment of AF.

Transseptal Retrieval of Dislodged Left Atrial Appendage Occlusion Device From the Left Ventricle

An 80-year-old male patient with permanent atrial fibrillation, CHA2DS2VASc score of 6, and HAS-BLED score of 5 was referred for implantation of a left atrial appendage occlusion device (LAAO) because of gastrointestinal bleeding under oral anticoagulation. After implantation of a 28-mm AMPLATZER-

APPLICATION OF 3D ECHOCARDIOGRAPHY GUIDANCE FOR WATCHMAN DEVICE IMPLANTATION

The Watchman device is a left atrial appendage (LAA) occlusion device, which is an effective alternative to oral anticoagulants in the prevention of thrombus formation in patients with atrial fibrillation (AF). Industry guidelines recommend standard 2D transesophageal echocardiography (TEE) images

Left atrial appendage occlusion: consensus document of Association of Cardiovascular Interventions and Heart Rhythm Section of Polish Cardiac Society

Left atrial appendage (LAA) occlusion devices have the potential to influence the clinical approach to stroke prevention in patients with atrial fibrillation. A number of percutaneous techniques have been proposed, including various intracardiac plugs and also external ligation. Several devices have been already used in Poland. One of them has been evaluated in randomised controlled trials compared with the current standard of care. Others are less well studied but quite commonly used in Eu-rope. It is anticipated that the use of LAA occlusion technologies in clinical practice will expand. This Consensus Document prepared jointly by Association of Cardiovascular Interventions (AISN) and Heart Rhythm Section (HRS) of Polish Cardiac Society seeks to highlight the critical issues surrounding LAA occlusion therapies and to facilitate the alignment of multiple interests, including those of primary care physicians, general cardiologists and procedural specialists (electrophysiologists and interventional cardiologists) but also other medical professionals. The article summarises current evidence and provides spe-cific recommendations on organisation and conduct of LAA therapy in patients with atrial fibrillation in Poland and defines also operator and institutional requirements fundamental to the establishment of successful LAA occlusion programmme.

Caught in The Act: A Case of Newly Developed Thrombus Jailed Within the Left Atrial Appendage by a Watchman Device

An 81-year-old female with a CHA2DS2-VASc score of 6 was admitted to this institution for elective insertion of a left atrial appendage occlusion device (Watchman device). The procedure was successful, with a 21-mm Watchman device inserted into the left atrial appendage after trans-septal puncture under fluoroscopic and transoesophageal echocardiographic (TOE) guidance. The device was stable with tug testing, and imaging revealed adequate device compression. The intraprocedural TOE showed Type IV appendage function with a peak appendage velocity of 40 cm/second, and no spontaneous echocardiographic contrast or thrombus. Day 1 transthoracic echocardiography (TTE) was unremarkable. The patient was discharged on protocol aspirin and clopidogrel for 6 months. One-month postoperatively the patient underwent TTE and TOE studies, which showed a 0.8 x 1 cm newly formed thrombus in the left atrial appendage trapped by the Watchman device. The patient had no neurological symptoms on follow-up. Device-related thrombus can occur on the atrial side, necessitating additional antithrombotic therapy in 3% of cases. It is believed that this is the first Australian case report of thrombus trapped within a Watchman device. The thrombus was unlikely to be clinically relevant, as the device was preventing any thromboembolic events in this high-risk patient. Longer term studies are needed to determine the best antiplatelet and anticoagulant regime to prevent any postprocedure thrombus formation.

Left Atrial Appendages Occlusion: Current Status and Prospective.

Stroke continues to be a major cause of morbidity and mortality in atrial fibrillation (AF) patients. Oral anticoagulation (OAC) provides protection against stroke and peripheral embolization in AF but significant proportion of patients could not be started on anticoagulation because of bleeding complications. Left atrial appendage harbors clot in about 90% of nonvalvular AF. The advent of left atrial appendage occlusion (LAAO) techniques has provided these patients with alternative to OAC for stroke prophylaxis. Multiple LAAO devices are currently available with Watchman and Amulet being the most commonly used in clinical practice. Randomized studies are available for Watchman device only. Data on Amplatzer Cardiac Plug, Amulet and Lariat devices are limited by the paucity of randomized data. Long-term data on different LAAO techniques are showing promising results. Device related thrombosis continues to be a serious complication associated with LAAO. Future studies should look into comparative effectiveness between different LAAO techniques, optimal patient selection, risk of complications, and anticoagulant treatment after LAAO. This article aims to provide current available evidence on efficacy and safety of different LAAO devices and future prospective.

Percutaneous left atrial appendage occlusion in atrial fibrillation patients with a contraindication to oral anticoagulation: a focused review.

Stroke is the most feared complication of atrial fibrillation (AF). Although oral anticoagulation with non-vitamin K antagonist and non-vitamin K antagonist oral anticoagulants (NOACs) have been established to significantly reduce risk of stroke, real-world use of these agents are often suboptimal due to concerns for adverse events including bleeding from both patients and clinicians. Particularly in patients with previous serious bleeding, oral anticoagulation may be contraindicated. Left atrial appendage occlusion (LAAO), mechanically targeting the source of most of the thrombi in AF, holds an immense potential as an alternative to OAC in management of stroke prophylaxis. In this focused review, we describe the available evidence of various LAAO devices, detailing data regarding their use in patients with a contraindication for oral anticoagulation. Although some questions of safety and appropriate use of these new devices in patients who cannot tolerate anticoagulation remain, LAAO devices offer a significant step forward in the management of patients with AF, including those patients who may not be able to be prescribed OAC at all. Future studies involving patients fully contraindicated to OAC are warranted in the era of LAAO devices for stroke risk reduction.

Thrombosis on a left atrial appendage occluder device

: A huge thrombus, developing after percutaneous left atrial appendage occlusion, has been successfully treated with dabigatran and aspirin as combination therapy.Although novel oral anticoagulants alone may be effective in thrombus dissolution, the association of an antiplatelet drug may safely enhance this process.

Available transvenous occluder designs and implantation techniques

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.

Printed MDCT 3D models for prediction of left atrial appendage (LAA) occluder device size: a feasibility study.

Transoesophageal echocardiography (TEE) and multidetector computed tomography (MDCT) currently serve as imaging modalities for left atrial appendage (LAA) occlusion preprocedural planning. We assessed the feasibility of MDCT-based models to predict the correct size of device for LAA occlusion procedures. Patients planned for LAA occlusion underwent MDCT before implantation, which was used for creating and printing 3D LAA models. Three cardiologists evaluated the 3D models and predicted the correct size of the device by manual manipulation. These predictions were compared with the actual device implanted during the procedure. Twenty-nine patients were included in this study. AMPLATZER and WATCHMAN devices were deployed in 12 and 17 patients, respectively. Two procedures were aborted due to failure of occlusion; all three physicians predicted it. There was good correlation between the 3D models and the inserted device for AMPLATZER devices with a concordance correlation coefficient of 0.778 (p=0.001) and poor agreement for WATCHMAN devices - concordance correlation coefficient of 0.315 (p=0.203). Agreement among the three physicians for AMPLATZER and WATCHMAN devices was excellent, with a calculated average intra-class correlation of 0.915 and 0.816, respectively. We found LAA printed 3D models to be accurate for prediction of LAA occluder device size for the AMPLATZER device but not for the WATCHMAN device.

Percutaneous Closure of Left Atrial Appendage affects Mid-Term Release of MR-proANP

The left atrial appendage (LAA) represents both a predisposing source of thrombus formation and of neuro-humoral haemostasis. This study aims to evaluate changes of biomarker expression before and after successful percutaneous closure of the LAA. Patients with atrial fibrillation and contraindication for oral anticoagulant therapy were enrolled. Blood samples were taken within 24 hours before (T1) and at least 6 months (mid-term) (T2) after successful implantation of LAA occlusion devices. Blood levels of high sensitivity troponin I and T (hsTnI, hsTnT), aminoterminal pro-brain natriuretic peptide (NT-proBNP) and mid-regional pro-atrial natriuretic peptide (MR-proANP) were evaluated at both time points. A total of 42 patients with successful percutaneous LAA closure were included. Median mid-term follow-up was of 183 days. HsTnT, hsTnI and NT-proBNP did not show any significant differences over time. Serum levels of MR-proANP increased significantly between immediate pre-intervention (T1: median = 245.7 pmol/l, IQR 155.8–361.3 pmol/l) and at mid-term follow-up (T2: median = 254 pmol/l, IQR 183.4–396.4 pmol/l) (p = 0.037). These results indicate, that percutaneous LAA closure affects neuro-humoral haemostasis by increasing MR-proANP serum levels at mid-term follow-up.

Pardon the Interruption: An Interrupted Inferior Vena Cava Discovered During Attempted Implantation of a Left Atrial Appendage Occlusion Device

A 76-year-old woman with paroxysmal atrial fibrillation (CHA2DS2-VASc score 4) and recurrent nose and gastrointestinal bleeds was referred for a Watchman left atrial appendage closure device (Boston Scientific, Natick, Massachusetts) implantation. Transthoracic echocardiography showed a mildly

Incidence, Characteristics, and Clinical Course of Device-Related Thrombus AfterWatchman Left Atrial Appendage Occlusion Device Implantation in Atrial Fibrillation Patients.

This study investigated characteristics and clinical impact of device-related thrombus formation after Watchman device implantation in atrial fibrillation (AF) patients. Left atrial appendage occlusion using the Watchman device is an effective alternative to anticoagulation for stroke prevention in AF patients. However, device-related thrombus formation remains an important concern after Watchman implantation. From 2006 to 2014, 119 consecutive AF patients underwent Watchman implantation. Transesophageal echocardiographic (TEE) follow-up was scheduled at 45 days, at 6 months, and at 12 months after the procedure. The incidence, characteristics, and clinical course of device-related thrombus formation detected by TEE were assessed. Follow-up TEE identified thrombus formation on the Watchman device in 4 patients (3.4%). The prevalence of chronic AF was 100% in patients with thrombus, which was higher than that for patients without thrombus (40.0%). Deployed device size was numerically larger in patients with thrombus (29.3 ± 3.8 mm vs. 25.7 ± 3.2 mm, respectively). All patients with thrombus discontinued any of the anticoagulant/antiplatelet therapy which was required under the study protocol. After restarting or continuing warfarin and aspirin therapy, complete resolution of the thrombus was achieved in all patients at subsequent follow-up TEE. Warfarin therapy was discontinued within 6 months for all cases, and there was no thrombus recurrence. The mean follow-up duration was 1,456 ± 546 days, with no death, stroke, or systemic embolization events in patients with thrombus. AF burden, device size, and anticoagulant/antiplatelet regimens can be associated with device-related thrombus after Watchman device implantation. Short-term warfarin therapy was effective, and the clinical outcomeswere favorable.

Anesthetic Management of Patients Undergoing Percutaneous Endocardial and Epicardial Left Atrial Appendage Occlusion.

Atrial fibrillation is the most common cardiac arrhythmia in adults affecting almost 6 million adults in the United States. The 2 most common comorbidities associated with atrial fibrillation are heart failure and thromboembolic events. Heart failure symptoms may be treated with rate control, antiarrhythmic medications or by catheter ablation. Unfortunately, despite optimal medical management, thromboembolic events still occur. Recently, there has been a great deal of interest and innovation in finding an alternative to chronic anticoagulation. Several percutaneous left atrial appendage occlusion devices have been developed over recent years, some of which have proven to be noninferior to anticoagulation in preventing strokes in atrial fibrillation patients. The 2 most widely used left atrial appendage occlusion devices are the WATCHMAN (Atritech Inc, Plymouth, MN, USA) and the LARIAT (SentreHEART, Palo Alto, CA, USA) devices. After a detailed description of the procedures, the anesthetic considerations of each procedure and management of specific adverse events are discussed within this review.

P282Utility of intracardiac ultrasound for guiding deployment of left atrial appendage occlusion devices for left atrial thrombus prevention

P282Utility of intracardiac ultrasound for guiding deployment of left atrial appendage occlusion devices for left atrial thrombus prevention

Who Should Be Referred for Left Atrial Appendage Occlusion Therapy?

Atrial fibrillation (AF) is the most common cardiac arrhythmia affecting approximately 7 million individuals in USA. It is one of the most significant arrhythmias, which accounts for a majority of embolic strokes, especially in elderly individuals. Although oral anti-coagulation is beneficial in lowering the risk of stroke, 1 in 10 patients have a contra-indication to warfarin therapy. Among patients who do tolerate either warfarin or novel oral anticoagulant (NOAC), major or recurrent bleeding, intracranial bleeds, etc. often lead to interruption of anti-coagulation. Previous studies have reported that >90% of cardioemboli in non-valvular atrial fibrillation (NVAF) originate in the left atrial appendage. Left atrial appendage occlusion (LAAO) is currently covered by the Centers for Medicare & Medicaid Services (CMS) as an alternative for stroke prevention in patients with an elevated stroke risk (CHADS2 ≥2 or CHA2DS2-VASc score ≥3) who have appropriate rational for avoiding long-term oral anticoagulation following a shared-decision making process. In this review, we discuss the currently available LAAO devices and more importantly, appropriate patient selection for this strategy.

Catheter Ablation of Ventricular Tachycardia in Patients With MitraClip Device: Preliminary Findings.

Patients with mitral regurgitation are increasingly treated by percutaneous implantation of a MitraClip device (Abbott Park, IL, USA). We investigate the feasibility and safety of the transmitral catheter route for catheter ablation of ventricular tachycardia (VT) in these patients. The mitral valve with the MitraClip in situ was crossed under transesophageal 3-dimensional echocardiographic and fluoroscopic guidance using a steerable sheath for ablation of the left ventricle. Five patients (all males, median age 74.0 ± 16.0 years) who had previously a MitraClip implanted were referred for catheter ablation of VT. The left ventricular ejection fraction was 29.0% ± 24.0%. One patient had both an atrial septal defect and a left atrial appendage occluder device in addition to a MitraClip. The duration between MitraClip implantation and ablation was 1019.0 ± 783.0 days. After transseptal puncture, ablation catheter was successfully steered through the mitral valve with the use of fluoroscopy. A complete high-density map of the substrate in sinus rhythm could be obtained in all patients using multipolar mapping catheters. In 1 patient, mapping was carried out using a mini-basket catheter. Procedural endpoints, noninducibility of all VTs, and abolition of all late potentials were achieved in all patients. Procedure time was 255.0 ± 52.5 minute, fluoroscopy time was 23.0 ± 7.3, and the radiation dose was 61.0 ± 37.5 Gycm2 . No mitral insufficiency or worsening of regurgitation was documented after the procedure. This is the first report demonstrating the feasibility and safety of VT ablation in patients with a MitraClip device using the anterograde transmitral catheter route.

Efficacy and Safety of the WATCHMAN Left Atrial Appendage System for Stroke Prevention in Chinese Patients with Nonvalvular Atrial Fibrillation: A Single-center, Prospective, Observational Study.

Background:In patients with nonvalvular atrial fibrillation (NVAF), embolic stroke is thought to be associated with left atrial appendage (LAA) thrombi. The WATCHMAN LAA Occlusion Device has been shown to be noninferior to conventional oral anticoagulation with warfarin for stroke prevention in patients with NVAF. This study aimed to evaluate the procedural feasibility, safety and 12-month outcomes of the WATCHMAN LAA Occlusion Device in NVAF patients with high risk for stroke in China.Methods:The clinical data of 106 NVAF patients, who were consecutively underwent LAA closure with the WATCHMAN Device between April 2014 and May 2015, were collected. Patients were followed up at 1, 3, 6, and 12 months after discharge. A transesophageal echocardiograph was performed at 45 days after implantation and repeated in case of an unexpected event during the follow-up period.Results:This study included 106 NVAF patients with a mean age of 64.2 ± 8.6 years (ranging from 50 to 88 years), and the mean CHA2DS2-VASc score of all patients was 3.6 ± 1.6 (ranging from 2 to 9). Among those 106 NVAF patients, 100 (94.3%) patients were implanted with the device successfully. The procedural success rate was 94.3% (100/106), and the occlusion rate was 100.0% (100/100). There were one tamponade, one ischemic stroke, and eight minor pericardial effusions during hospitalization. During 12-month follow-up period, two patients developed a thrombus layer on the device that resolved with additional anticoagulation: one with visible device-thrombus experienced transient ischemic stroke, and one had a hemorrhagic stroke. There were no deaths in this study. The overall survival rate was 100.0%, and nonmajor adverse event rate was 95.0% (95/100). In this study, the expected annual rate of ischemic stroke risk in these patients according to the CHA2DS2-VASc score was 4.0%, while the observed ischemic stroke rate was 2.0% per year.Conclusions:LAA closure with the WATCHMAN Device was feasible, efficient, and safe for NVAF to prevent the accidence of stroke in Chinese patients. During the 12-month follow-up period, the observed ischemic stroke rate (2.0% per year) in our study was lower than the predicted annual stroke risk (4.0%) using the CHA2DS2-VASc score.