Left atrial appendage closure devices

Amplatzer amulet versus watchman device for percutaneous left atrial appendage closure: A systematic review and meta-analysis

BACKGROUND

The Amplatzer Amulet (AA) and Watchman devices (WD) are the 2 most frequently used devices for percutaneous LAA closure globally.

OBJECTIVE

To evaluate the safety and clinical outcomes associated with these 2 devices in patients undergoing percutaneous LAA closure.

METHOD

We systematically searched all electronic databases from inception until February 21, 2023. The primary endpoint was procedure related complications. Secondary endpoints were device related thrombus, stroke, cardiovascular mortality, peri device leak, systemic embolism, and all-cause mortality.

RESULTS

A total of 3 randomized clinical trials with 2150 patients were included in this meta-analysis. The mean age was 75 and 76 years in the Amplatzer group and in the Watchman group, respectively. The odds of procedure-related complications (OR, 1.80 [95% CI: 1.21-2.67], P < .001) were significantly higher among patients with AA compared to the WD. However, the odds of all-cause mortality (OR, 0.75 (95% CI: 0.49-1.16), P = .20), stroke (OR, 0.79 [95% CI: 0.47-1.34], P = .39), systemic/pulmonary embolism (OR, 1.34 [95% CI: 0.30-6.04], P = .70), and major bleeding (OR, 1.10 [95% CI: 0.83-1.48], P = .50) were comparable between the two devices. The odds of device related thrombus (OR, 0.72 [95% CI: 0.46-1.14], P = .17) was comparable between both the group of patients, however the incidence of peri device leak was significantly lower in AA group (OR, 0.41 [95% CI: 0.26-0.66], P < .001) compared with WD group of patients.

CONCLUSION

The AA was not superior to the Watchman device in terms of safety and efficacy. However, the Amulet occluder was associated with a higher incidence of procedure-related complications, and lower peri device leak.

Causes and predictors of immediate and short-term readmissions following percutaneous left atrial appendage closure procedure

INTRODUCTION

Percutaneous left atrial appendage device closure has been offered as an alternative to anticoagulation for high-risk patients with nonvalvular atrial fibrillation. Given the relative novelty of the procedure, we aimed to analyze the rates and causes of immediate (30 days) and short-term (90 days) readmission after the procedure.

METHODS

We performed a retrospective observational study using the Nationwide Readmissions Database for 2018. We studied 29 449 hospitalizations for percutaneous left atrial appendage (LAA) device closure.

RESULTS

In both the 30- and 90-day cohorts, the most common causes of readmissions were gastrointestinal bleeding (16.1% and 14.8%), heart failure exacerbation (11.1% and 11.6%), and atrial fibrillation (6.2% and 7.2%). Female sex, liver disease, chronic kidney disease, chronic pulmonary disease, presence of heart failure, human immunodeficiency virus/acquired immunodeficiency syndrome status, and diabetes mellitus were independently associated with higher odds of readmission in both cohorts.

CONCLUSION

Our study highlights the need for further deliberation on the choice and duration of anticoagulation periprocedurally after percutaneous LAA closure, especially among those with high bleeding risk. It also highlights the need for optimization of heart failure status periprocedurally to avoid readmissions for exacerbations.

Safety and efficacy of the Amplatzer amulet and watchman2.5 for left atrial appendage occlusion: a Systematic review and meta-analysis

BACKGROUND

Left atrial appendage occlusion (LAAO) is an alternative to oral anticoagulation (OAC) to decrease the risk of stroke in patients with nonvalvular atrial fibrillation (NVAF); however, certain complications remain a concern. Amplatzer Amulet and Watchman are the two most popular used devices for preventing stroke in patients with NVAF. We assessed the safety and efficacy of LAAO using the Amplatzer Amulet and Watchman.

METHODS

A meta-analysis was conducted to compare the safety and efficacy outcomes associated with the use of the Amplatzer Amulet and Watchman 2.5. The Newcastle-Ottawa Scale has been utilized to assess the quality of study.

RESULTS

The meta-analysis includes seven studies involving 2,926 patients (1,418 patients with an amulet and 1,508 with a Watchman 2.5). Generally, adverse event rates for both systems were minimal. No significant differences between the two devices were found in safety (pericardial effusion, device embolization, and cardiac tamponade) or efficacy outcomes (death, TIA, stroke, major/minor bleeding, device leak, and thromboembolic events).

CONCLUSIONS

The data suggest LAAO is a safe procedure, regardless of which device was used. LAAO devices generally have low complication rates. Outcomes were comparable between the two groups with no significant differences in their safety or efficacy. This article is protected by copyright. All rights reserved.

Large Device-Related Thrombus Detected following Symptoms of Transient Ischemic Attack

As an independent risk factor for stroke, atrial fibrillation has been shown to be associated with a fivefold increase in the cause of embolic stroke in comparison to healthy individuals without atrial fibrillation. This risk may be compounded by other factors; however, the main probable cause of stroke leading from atrial fibrillation is thrombus formation in the left atrial appendage. In patients for whom anticoagulation is contraindicated, left atrial appendage occlusion has become a leading alternative option for therapeutic prevention of thromboembolism and stroke in patients with this condition. Unfortunately, these devices (particularly the WATCHMAN) have been associated with a 3-6% incidence of intracardiac thrombus development postimplantation. Some risk factors for the development of device-related thrombus are high platelet count, permanent atrial fibrillation, resistance to clopidogrel, and prior transient ischemic attack or stroke. Despite following an anticoagulant regimen, thrombus formation was reported in 5.6% of participants of a randomized clinical trial, and further analysis showed that some of these patients continued to develop either ischemic stroke or thromboembolism five years later as compared to patients without initial thrombus development. We present a case of an elderly male with prior history of stroke and transient ischemic attack who developed a large device-related thrombus five months following WATCHMAN FLX™ implantation. Currently, there are no specific recommendations on the management of this rare complication; however, we discuss possible consideration of initially prolonging anticoagulation therapy following implantation for high-risk individuals, as there is an increased possibility for thrombus formation in this population. Management options should continue to be studied for therapeutic benefit in streamlining postprocedural therapy and improve future outcomes in the use of left atrial appendage occlusion devices, as well as continual thrombus prevention.

Demonstration of proof-of-concept of StrokeShield system for complete closure and occlusion of the left atrial appendage for non-valvular atrial fibrillation therapy

In the US, the most significant morbidity and mortality associated with non-valvular atrial fibrillation (NVAF) is embolic stroke, with 90% of thrombus originating from the left atrial appendage (LAA). Anticoagulation is the preferred treatment for the prevention of stroke in NVAF patients, but clinical studies have demonstrated high levels of non-compliance and increased risk of bleeding or ineligibility for anticoagulation therapy, especially in the elderly population where the incidence of NVAF is highest. Alternatively, stroke may be preventing using clinically approved surgical and catheter-based devices to exclude or occlude the LAA, but these devices continue to be plagued by peri-device leaks and thrombus formation because of residual volume. To overcome these limitations, Cor Habere (Louisville, KY) and the University of Louisville are developing a LAA closure device (StrokeShield) that completely occludes and collapses the LAA to minimize the risk of stroke. The StrokeShield device is a collapsible occluder (nitinol reinforced membrane) that completely covers the LAA orifice with an expandable conical coil anchor that attaches to the myocardium. The device is designed for catheter-based delivery and expands to completely occlude the LAA orifice and collapse the LAA. The primary advantages of the StrokeShield system are a completely sealed LAA (no peri-device flow or residual space) and smooth endothelialized connection to the left atrial wall with minimal risk of cardiac bleeding and tamponade. We tested proof-of-concept of a prototype StrokeShield device in acute (n = 2) and chronic 60-day (n = 2) healthy canine models. Acute results demonstrated that the conical coil securely attached to the myocardium (5N pull-out force) and the Nitinol umbrella fully deployed and covered the LAA ostium. Results from the chronic implants demonstrated long-term feasibility of device placement with no procedural or device-related intra- or post-operative complications, secure placement and correct positioning of the device with no device migration. The device successfully occluded the LAA ostium and collapsed the LAA with no interference with the mitral valve, circumflex coronary artery, or pulmonary veins. Necropsy demonstrated no gross signs of thrombus or end-organ damage and the device was encapsulated in the LAA. Histology demonstrated mature neointima covering the device with expected foreign body inflammatory response. These early positive results will help to guide the iterative design process for the continued development of the StrokeShield system.

Meta-Analysis Comparing WatchmanTM and Amplatzer Devices for Stroke Prevention in Atrial Fibrillation

Background: For patients with atrial fibrillation who are at high risk for bleeding or who cannot tolerate oral anticoagulation, left atrial appendage (LAA) closure represents an alternative therapy for reducing risk for thromboembolic events. Objectives: To compare the efficacy and safety of the Amplatzer and Watchman^TM LAA closure devices. Methods: A meta-analysis was performed of studies comparing the safety and efficacy outcomes of the two devices. The Newcastle-Ottawa Scale was used to appraise study quality. Results: Six studies encompassing 614 patients were included in the meta-analysis. Overall event rates were low for both devices. No significant differences between the devices were found in safety outcomes (i.e., pericardial effusion, cardiac tamponade, device embolization, air embolism, and vascular complications) or in the rates of all-cause mortality, cardiac death, stroke/transient ischemic attack, or device-related thrombosis. The total bleeding rate was significantly lower in the Watchman^TM group (Log OR = -0.90; 95% CI = -1.76 to -0.04; p = 0.04), yet no significant differences was found when the bleeding rate was categorized into major and minor bleeding. Total peridevice leakage rate and insignificant peridevice leakage rate were significantly higher in the Watchman^TM group (Log OR = 1.32; 95% CI = 0.76 to 1.87; p < 0.01 and Log OR = 1.11; 95% CI = 0.50 to 1.72; p < 0.01, respectively). However, significant peridevice leakages were similar in both the devices. Conclusions: The LAA closure devices had low complication rates and low event rates. Efficacy and safety were similar between the systems, except for a higher percentage of insignificant peridevice leakages in the Watchman^TM group. A randomized controlled trial comparing both devices is underway, which may provide more insight on the safety and efficacy outcomes comparison of the devices.

Initial experience of percutaneous left atrial appendage closure using the LAmbre device for thromboembolic prevention

AIMS

Stroke due to atrial fibrillation has been associated with a high risk of disability and mortality. Percutaneous left atrial appendage (LAA) closure has been established as an alternative strategy for stroke prevention in patients not eligible for oral anticoagulation. The LAmbre is a novel occluder, specifically designed for LAA closure adaptive to various LAA anatomies. The aim of this study was to demonstrate feasibility and initial experience in a nonprescreened patient cohort for LAA occlusion using the novel LAmbre occluder.

METHODS

The device was implanted in 11 patients with nonvalvular atrial fibrillation. Follow-up included transesophageal echocardiography and an outpatient visit at 6 weeks and 6 months after implantation.

RESULTS

All devices were implanted successfully. Device sizes ranged from 16/22 to 22/34 mm. Patients' mean CHA2DS2-VASc and HAS-BLED scores were 3.3 ± 1.0 and 3.2 ± 1.0, respectively. Two out of 11 patients had previously been rejected for Watchman occluder implantation by reasons of too small LAA. At 6 weeks and 6 months, there were no deaths, strokes, systemic thromboembolism or severe bleeding complications. There was no device-related thrombus or pericardial effusion seen with transesophageal echocardiography. In one out of 11 patients, a minimal peridevice flow (less than 5 mm) was present at 6-week follow-up.

CONCLUSION

The LAmbre occluder is a novel LAA-closure device with features that provide many options for LAA-closure to physicians, particularly in patients with challenging anatomies. From our initial experience, implantation is associated with a good success rate and clinical outcome.

Complete Obliteration of the Left Atrial Appendage: An Analysis of Epicardial Excision and Novel Pericardial Patch Exclusion

OBJECTIVE

Conventional epicardial excision is believed to be the most effective method of surgically obliterating the left atrial appendage (LAA), although incomplete resection and residual LAA volume may undermine its effectiveness. We sought to compare the impact of conventional epicardial excision with a novel LAA pericardial patch exclusion on residual LAA volume.

METHODS

We performed LAA obliteration using pericardial patch exclusion, followed by conventional epicardial excision, in 27 cadaveric hearts. After each procedure, residual LAA volume was measured by two different techniques and compared with baseline volume. There was no difference in baseline LAA volume between each procedure.

RESULTS

Procedural success was achieved in all hearts. Conventional epicardial excision left a residual LAA volume of 0.95 mL (24%), as compared with pericardial patch exclusion, which left a residual volume of 0.17 mL (4%, P = 0.0001). Further analysis of fixed and fresh hearts showed that reduction of LAA volume was more pronounced in the fresh hearts, suggesting effectiveness in live patients. Neither technique resulted in any significant change in the endocardial shape of the LAA orifice or injury to the circumflex artery.

CONCLUSIONS

Conventional epicardial excision of the LAA results in significantly more residual LAA volume, which may have important implications in persistent stroke risk. Pericardial patch exclusion seems to achieve near-total elimination of the LAA and may be a superior surgical option.