Left atrial appendage occlusion with the AMPLATZER Amulet device: an expert consensus step-by-step approach

Less major bleeding and higher hemoglobin after left atrial appendage closure in high-risk patients: Data from a long-term, longitudinal, two-center observational study

BACKGROUND

Left atrial appendage closure (LAAC) is a mechanical alternative for stroke prevention in patients at risk who cannot tolerate oral anticoagulation (OAC).

HYPOTHESIS

Our hypothesis was that the reduction of anticoagulation following LAAC results in a decrease of bleeding events and a rise in serum hemoglobin in a high-risk collective of patients with atrial fibrillation (AF).

METHODS

Bleeding events, use of erythrocyte concentrates, anticoagulation, embolic events, and serum hemoglobin levels before and following LAAC were compared over more than 4 years.

RESULTS

Seventy-five patients (CHA₂DS₂-VASc score 4.4 ± 1.7, HAS-BLED score 4.6 ± 1.1) were analyzed. Before LAAC (observation period 1.8 ± 1.8 years), 67 patients experienced 1.8 ± 1.4 bleeding events (0.9 ± 1.3 major) per year resulting in 0.7 ± 1.3 transfusions per year. After LAAC (2.6 ± 2.0 years), 26 patients (p < .0001 vs. before) had 0.6 ± 2.1 bleeding events (p < .0001), 0.2 ± 0.6 major bleedings (p < .0001) and received 0.6 ± 1.9 transfusions per year (p = .671). Fourteen patients had stroke before and 3 after LAAC (p = .008). Serum hemoglobin increased from initially 9.9 ± 3.0 to 11.9 ± 2.3 g/dL until the end of follow-up (p = .0005). Adverse embolic events did not differ before and after LAAC in our collective.

CONCLUSION

In this clinical relevant cohort of AF patients with high risk for stroke and intolerance to OAC, we show that LAAC was able to reduce the rate of stroke and bleeding events, which translated into a rising serum hemoglobin concentration.

Safety and Healthcare Resource Utilization in Patients Undergoing Left Atrial Appendage Closure-A Nationwide Analysis

Percutaneous left atrial appendage closure (LAAC) has emerged as a non-pharmacological alternative for stroke prevention in patients with atrial fibrillation (AF) not suitable for anticoagulation therapy. Real-world data on peri-procedural outcomes are limited. The aim of this study was to analyze outcomes of peri-procedural safety and healthcare resource utilization in 11,240 adult patients undergoing LAAC in the United States between 2016 and 2019. Primary outcomes (safety) were in-hospital ischemic stroke or systemic embolism (SE), pericardial effusion (PE), major bleeding, device embolization and mortality. Secondary outcomes (resource utilization) were adverse discharge disposition, hospital length of stay (LOS) and costs. Logistic and Poisson regression models were used to analyze outcomes by adjusting for 10 confounders. SE decreased by 97% between 2016 and 2019 [95% Confidence Interval (CI) 0-0.24] (p = 0.003), while a trend to lower numbers of other peri-procedural complications was determined. In-hospital mortality (0.14%) remained stable. Hospital LOS decreased by 17% (0.78-0.87, p < 0.001) and adverse discharge rate by 41% (95% CI 0.41-0.86, p = 0.005) between 2016 and 2019, while hospital costs did not significantly change (p = 0.2). Female patients had a higher risk of PE (OR 2.86 [95% CI 2.41-6.39]) and SE (OR 5.0 [95% CI 1.28-43.6]) while multi-morbid patients had higher risks of major bleeding (p < 0.001) and mortality (p = 0.031), longer hospital LOS (p < 0.001) and increased treatment costs (p = 0.073). Significant differences in all outcomes were observed between male and female patients across US regions. In conclusion, LAAC has become a safer and more efficient procedure. Significant sex differences existed across US regions. Careful considerations should be taken when performing LAAC in female and comorbid patients.

Regulation, approval, and access of spinal implants in low-middle-income countries: a narrative review and case study

INTRODUCTION

Spinal implants play a vital role in healthcare delivery, and regulations are necessary to ensure their quality, approval, access, and use. In this article, we examine the current state of regulation and approval procedures for medical devices in low- and middle-income countries (LMICs), emphasizing the situation in Tanzania.

AREAS COVERED

We conducted a systematic literature search and interviewed a local spine implant representative to investigate the approval, availability, and access of surgical and spinal implants in LMICs, particularly in Africa. Out of the 18 included articles, six referred to African regulations, with no mention of spinal implants. Our analysis revealed that LMICs face challenges in accessing implants due to affordability, poor supply chain, and lack of expertise for their application. However, surgeons have found alternative solutions, such as using lower-cost implants from Turkish manufacturers. The Tanzania Medical Devices and Drugs Authority oversees the local regulatory and approval process for implants.

EXPERT OPINION

Regulation and accessibility of spinal implants in LMICs, particularly in Africa, are limited and negatively impact patient care and best medical practice. Potential solutions include capacity building within and collaboration among regulatory organizations to improve regulatory processes and allocating financial resources to qualitative and quantitative implant access.

SCAI/HRS Expert Consensus Statement on Transcatheter Left Atrial Appendage Closure

Exclusion of the left atrial appendage to reduce thromboembolic risk related to atrial fibrillation was first performed surgically in 1949. Over the past 2 decades, the field of transcatheter endovascular left atrial appendage closure (LAAC) has rapidly expanded, with a myriad of devices approved or in clinical development. The number of LAAC procedures performed in the United States and worldwide has increased exponentially since the Food and Drug Administration approval of the WATCHMAN (Boston Scientific) device in 2015. The Society for Cardiovascular Angiography & Interventions (SCAI) has previously published statements in 2015 and 2016 providing societal overview of the technology and institutional and operator requirements for LAAC. Since then, results from several important clinical trials and registries have been published, technical expertise and clinical practice have matured over time, and the device and imaging technologies have evolved. Therefore, SCAI prioritized the development of an updated consensus statement to provide recommendations on contemporary, evidence-based best practices for transcatheter LAAC focusing on endovascular devices.

The Strengths and Weaknesses of the LAA Covering Disc Occluders-Conceptually and in Practice

Endocardial left atrial appendage (LAA) occluders with a covering disc encompass a wide range of devices that share the common feature of a distal anchoring "body" and proximal covering "disc" design. This unique design feature has potential advantages in certain complex LAA anatomies and challenging clinical scenarios. The current review article summarizes the different features of established and novel devices, preprocedural imaging updates, intraprocedural technical considerations, and postprocedural follow-up issues specific to this category of LAA occluders.

SCAI/HRS expert consensus statement on transcatheter left atrial appendage closure

Exclusion of the left atrial appendage to reduce thromboembolic risk related to atrial fibrillation was first performed surgically in 1949. Over the past 2 decades, the field of transcatheter endovascular left atrial appendage closure (LAAC) has rapidly expanded, with a myriad of devices approved or in clinical development. The number of LAAC procedures performed in the United States and worldwide has increased exponentially since the Food and Drug Administration approval of the WATCHMAN (Boston Scientific) device in 2015. The Society for Cardiovascular Angiography & Interventions (SCAI) has previously published statements in 2015 and 2016 providing societal overview of the technology and institutional and operator requirements for LAAC. Since then, results from several important clinical trials and registries have been published, technical expertise and clinical practice have matured over time, and the device and imaging technologies have evolved. Therefore, SCAI prioritized the development of an updated consensus statement to provide recommendations on contemporary, evidence-based best practices for transcatheter LAAC focusing on endovascular devices.

Looking for optimal antithrombotic strategy after transcatheter left atrial appendage occlusion: a real-world comparison of different antiplatelet regimens

BACKGROUND

Transcatheter left atrial appendage occlusion (LAAO) has emerged as an effective procedure for the prevention of thromboembolic events in non-valvular atrial fibrillation (AF) patients with contraindications to oral anticoagulation. After the procedure, different antithrombotic regimens have been used, in order to prevent device-related thrombus and trying to minimize bleedings. The search for the optimal antithrombotic strategy is still ongoing. We sought to assess efficacy and safety of different antiplatelet therapy (APT) regimens.

METHODS

We enrolled non-randomized consecutive patients who underwent LAAO at the University Hospital of Parma between 2010 and 2021. Three study groups were identified according to post-procedural APT: long (>1, ≤12 months)-dual APT (DAPT), short (≤ 1 month)-DAPT, lifelong single APT (SAPT). The choice of the APT was left to multidisciplinary team evaluation. The incidence of the primary outcome, a composite of any ischemic or hemorrhagic event, was assessed at follow-up.

RESULTS

We enrolled a total of 130 patients. Technical success was achieved in 123 (94.6%) patients. After LAAO, 39 [31.7%] patients were discharged on short-DAPT, 35 [28.5%] on long-DAPT and 49 [39.8%] on SAPT. After a median follow-up of 32 months, short-DAPT group had a significantly lower occurrence of the primary outcome (3 [7.7%] vs. 7 [20.0%] in long-DAPT vs. 14 [28.6%] in SAPT, p = 0.049], mainly driven by a lower occurrence of the bleeding endpoint (0 vs. 4 [11.4%] in long-DAPT vs. 9 [18.4%] in SAPT, p = 0.020). Finally, comparison of the Kaplan-Meier curves showed that short-DAPT group had a higher primary endpoint-free survival [p = 0.015] compared to the other groups.

CONCLUSION

Post-procedural short-DAPT strategy was associated with better outcomes, mainly driven by reduction of major bleedings.

Left atrial appendage closure for stroke prevention in nonvalvular atrial fibrillation: A current overview

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice and its prevalence increases with age. AF causes palpitations, heart failure, and cardiogenic embolism. Of them, the most critical and fatal complication is a cardio-embolic event. Oral anticoagulation plays a central role in reducing stroke risk in AF patients. Recently, when oral anticoagulation is considered in patients with non-valvular AF who are eligible for direct oral coagulations, they are preferred to vitamin K antagonist based on accumulating evidence. Although many patients can tolerate oral anticoagulation, there is a subset of patients who cannot tolerate long-term oral anticoagulation. Such a subset has a higher bleeding risk as indicated by the HAS-BLED score under oral anticoagulation. This subset of patients requires effective and safe non-pharmacological alternative therapies for stroke prevention. One of the promising non-pharmacological therapies is left atrial appendage closure. Three randomized controlled trials demonstrated non-inferiority of percutaneous left atrial appendage closure using WATCHMAN family to oral anticoagulation (Boston Scientific, Marlborough, MA, USA). WATCHMAN FLX, which was innovated following WATCHMAN 2.5, was associated with fewer safety events and a higher success rate of effective appendage closure. Nevertheless, several unsolved issues remain, including device-related thrombosis, post-treatment antithrombotic therapy, and peri-device leakage. Left atrial appendage closure for patients with non-valvular AF may be an alternative therapy to avoid cardiac embolism for high bleeding risk patients with contraindications to long-term oral anticoagulation therapy.

Stroke prevention of thoracoscopic left atrial appendage clipping in patients with non-valvular atrial fibrillation at high risk of stroke and bleeding: study protocol for a non-randomised controlled clinical trial

INTRODUCTION

Non-valvular atrial fibrillation (NVAF) is a high-risk factor for ischaemic stroke. The 2016 European Society of Cardiology Atrial Fibrillation Management guidelines recommend oral anticoagulants (OACs) to prevent stroke in men with CHA₂DS₂-VASc scores ≥2 and women ≥3. However, in patients with a high risk of stroke and a high risk of bleeding (HAS-BLED (Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile international normalized ratio, Elderly (> 65 years), Drugs/alcohol concomitantly) score≥3), OAC had a higher risk of bleeding. Left atrial appendage closure (LAAC) is non-inferior to OAC as a means of preventing stroke in several studies. As a minimally invasive intervention to prevent stroke, transthoracic LAAC (TS-LAAC) has a high successful closure rate, but there is a lack of literature reports directly comparing it with OAC. Our research compares TS-LAAC with novel oral anticoagulants (NOACs) and provides an appropriate programme for stroke prevention in a specific population.

METHODS AND ANALYSIS

This is a non-randomised controlled trial study protocol, and we will conduct this study from April 2022 to April 2025. The study included 186 patients with confirmed NVAF, 93 of whom completed thoracoscopic LAAC, and the control group treated with NOACs. The primary outcome was the incidence of stroke and systemic embolism, as well as the composite endpoint events (stroke, systemic embolism, myocardial infarction, bleeding, cardiovascular death, etc). Secondary outcomes were ischaemic stroke, haemorrhagic stroke, any bleeding events, death from cardiovascular causes, death from all causes, residual root rate in the surgery group, device-related thrombosis in the surgery group, changes in blood pressure, cardiac chamber size changes, etc. Each subject completed at least 1 year of follow-up.

ETHICS AND DISSEMINATION

The study has been approved by the Medical Ethics Committee of Beijing Tiantan Hospital, Capital Medical University, China (approval number: KY2022-013-02). The results from this study will be disseminated through manuscript publications and national/international conferences.

TRIAL REGISTRATION NUMBER

ChiCTR2200058109.

The Strengths and Weaknesses of the LAA Covering Disc Occluders-Conceptually and in Practice

Endocardial left atrial appendage (LAA) occluders with a covering disc encompass a wide range of devices that share the common feature of a distal anchoring "body" and proximal covering "disc" design. This unique design feature has potential advantages in certain complex LAA anatomies and challenging clinical scenarios. The current review article summarizes the different features of established and novel devices, preprocedural imaging updates, intraprocedural technical considerations, and postprocedural follow-up issues specific to this category of LAA occluders.

Long-term outcomes of percutaneous left atrial appendage closure for the prevention of stroke in patients with atrial fibrillation: Asia-Pacific experience

BACKGROUND/PURPOSE

In patients with non-valvular atrial fibrillation (NVAF), the left atrial appendage occluder (LAAO) is an alternative treatment for stroke prevention. However, the long-term outcomes in Asia was generally unknown.

METHODS AND RESULTS

This was a retrospective longitudinal study and a total of 124 patients with contraindications to oral anticoagulants or stroke despite under anticoagulants had been enrolled since 2013. Primary efficacy was defined as any type of stroke/systemic embolization and adverse event as any procedure or anti-thrombotic related complications. Twelve patients were excluded due to thrombus in the LAA or oversize LAA. Watchman was successfully implanted in 55 patients (98%) and ACP/Amulet also 55 patients (98%). During follow-up, the ischemic stroke rate was 1.9 in the Watchman and 1.4 per 100 patient-year in the ACP/Amulet group. There were 2 Watchman patients experiencing intracranial hemorrhage. Device-related thrombus (DRT) was noted in 3 patients (2.7%).There was no patient with peri-device lead ≧5 mm. In those patients receiving only local anesthesia, the follow-up echocardiography showed no significant peri-device leak, malposition of LAAO and DRT.

CONCLUSION

This long-term follow-up study shows that percutaneous closure of LAA is a safe and technically feasible procedure with satisfactory outcomes in Asia. The procedure success rate, efficacy and adverse event were similar to those reported in the Caucasian populations.

Comparison between Amulet and Watchman left atrial appendage closure devices: A real-world, single center experience

Background

Data reporting a head-to-head comparison between Amulet and Watchman devices are scarce. The aim of this study was to compare the Watchman™ versus Amulet™ left atrial appendage closure (LAAC) devices in a consecutive, industry-independent registry.

Methods

Patients who underwent LAAC using Watchman or Amulet devices from January 2014 to December 2019 at the University Heart Center Lübeck, Lübeck, Germany were included in the present analysis. Primary endpoints included periprocedural complications (in-hospital death, pericardial tamponade, device embolization, stroke, major bleeding and vascular access complications), and complications during long-term follow-up (ischemic stroke, hemorrhagic stroke, thromboembolism, device thrombus, bleeding and death).

Results

After matching the patients for age (±5 years), gender, CHA2DS2Vasc score (±1) and HASBLED score (±1), each of the Watchman and the Amulet groups included 113 patients. Patients in the Amulet group had significantly more periprocedural complications (2.7% vs 10.6%, p = 0.029; respectively) and more major bleeding complications (0% vs 5.3%, p = 0.029; respectively). During long-term follow-up, the rate of events was comparable between the Watchman and Amulet groups (18.3% versus 20.8%, p = 0.729; respectively).

Conclusion

Amulet LAAC device was associated with increased periprocedural complications as compared to Watchman LAAC device. On long-term follow-up, both devices showed comparable efficacy and safety.

Low Dose of Direct Oral Anticoagulants after Left Atrial Appendage Occlusion

The optimal antithrombotic strategy following left atrial appendage occlusion (LAAO) is not yet clearly established. Low-dose non-vitamin K antagonist oral anticoagulants (NOAC) might represent a valid alternative, but data regarding their usage is scarce. The aim of this study was to examine the efficacy and safety of low-dose NOAC compared to single (SAPT) or dual antiplatelet therapies (DAPT) after LAAO. We included consecutive patients with non-valvular atrial fibrillation who underwent LAAO and received low-dose apixaban, SAPT, or DAPT at discharge. The primary objective of this study included an efficacy endpoint (thromboembolic events and device related thrombosis (DRT)) and a safety endpoint (incidence of major bleeding) within the first three months after LAAO. A total of 139 patients were included. This group involved SAPT in 26 (18%), DAPT in 73 (53%), and apixaban in 40 (29%) patients. Follow-up at three-months showed no significant differences in the primary efficacy endpoint (2 (8%) SAPT, 3 (4%) DAPT and 0 (0%) apixaban; p value = 0.25). In contrast, the primary safety endpoint occurred more frequently in DAPT patients (7 (10%) DAPT, 0 (0%), SAPT and 0 with apixaban; p value = 0.03). Combining both efficacy and safety outcomes, low dose apixaban had a lower rate of events (2 (8%) with SAPT, 9 (12%) with DAPT and 0 (0%) with apixaban; p = 0.046). Low-dose apixaban after LAAO may be a valid alternative to DAPT and SAPT as depicted by the reduction in the occurrence of major bleedings and combined DRT/major bleedings respectively. Randomized data will be necessary to validate this strategy.

Comparative data on left atrial appendage occlusion efficacy and clinical outcomes by age group in the Amplatzer™ Amulet™ Occluder Observational Study

AIMS

Left atrial appendage occlusion (LAAO) may be considered for patients with non-valvular atrial fibrillation (NVAF) and a relative/formal contraindication to anticoagulation. This study aimed to summarize the impact of aging on LAAO outcomes at short and long-term follow-up.

METHODS AND RESULTS

We compared subjects aged <70, ≥70 and <80, and ≥80 years old in the prospective, multicentre Amplatzer™ Amulet™ Occluder Observational Study (Abbott, Plymouth, MN, USA). Serious adverse events (SAEs) were reported from implant through a 2-year post-LAAO visit and adjudicated by an independent clinical events committee. Overall, 1088 subjects were prospectively enrolled. There were 265 subjects (24.4%) <70 years old, 491 subjects (45.1%) ≥70 and <80 years old, and 332 subjects (30.5%) ≥80 years old, with the majority (≥80%) being contraindicated to anticoagulation. As expected, CHA2DS2-VASc and HAS-BLED Scores increased with age. Implant success was high (≥98.5%) across all groups, and the proportion of subjects with a procedure- or device-related SAE was similar between groups. At follow-up, the observed ischaemic stroke rate was not significantly different between groups, and corresponding risk reductions were 62, 56, and 85% when compared with predicted rates for subjects <70, ≥70 and <80, and ≥80 years old, respectively. Major bleeding and mortality rates increased with age, while the incidence of device-related thrombus tended to increase with age.

CONCLUSIONS

Despite the increased risk for ischaemic stroke with increasing age in AF patients, LAAO reduced the risk for ischaemic stroke compared with the predicted rate across all age groups without differences in procedural SAEs.

Gender difference in left atrial appendage occlusion outcomes: Results from the Amplatzer™ Amulet™ Observational Study

Background

Percutaneous LAAO represents an alternative for stroke prevention in patients not tolerating anticoagulation. While women are at higher risk of complications during percutaneous coronary or valvular interventions, the impact of gender on LAAO outcomes is not well characterized. The current study assessed potential gender-related differences in procedural and long-term outcomes following left atrial appendage occlusion (LAAO).

Methods

1088 AF patients were enrolled in the prospective, multicenter, Amplatzer™ Amulet™ Observational Study and followed for 2 years with scheduled adverse event assessments. The prespecified primary outcome was ischemic stroke, systemic embolism or cardiovascular (CV) death at 2 years. We also compared the rate of procedural success, device-related thrombus (DRT) and major bleeding between genders.

Results

702 men and 386 women underwent LAAO. Implant successwas high, and similar between men and women (98.9 vs 99.5%, p = 0.58). Similarly, no difference was observed in the primary outcome (12.0 vs 12.5%, p = 0.82). Compared to the CHA₂DS₂-VASc predicted rate, we observed a numerically greater absolute risk reduction of ischemic stroke in women (from 7.6 to 2.1%/year) than men (from 6.2 to 2.2%/year). DRT through 2 years was similar between groups (1.6%, p = 0.96). We found no significant gender difference in terms of periprocedural or long-term (7.1 vs 7.6%/year) major bleeding.

Conclusions

In this large group of patients undergoing LAAO using the Amplatzer™ Amulet™ device we found no significant gender difference in terms of procedural or long-term clinical outcomes. Similarly to oral anticoagulation, device-based LAA occlusion renders AF-related stroke risk similar in women and men.

Clinical trial registration

Clinicaltrials.gov Identifier: NCT02447081.

https://clinicaltrials.gov/ct2/show/NCT02447081.

Current practice and future prospects in left atrial appendage occlusion

The thromboembolic complications of Atrial fibrillation (AF) remain a major problem in contemporary clinical practice. Despite advances and developments in anticoagulation strategies, therapy is complicated by the high risk of bleeding complications and need for meticulous medication compliance. Over the past few decades, the left atrial appendage has emerged as a promising therapeutic target to prevent thromboembolic events while mitigating bleeding complications and compliance issues. Emerging data indicates that it is a safe, effective and feasible alternative to systemic anticoagulation in patients with non-valvular AF. A number of devices have been developed for endocardial or epicardial based isolation of the left atrial appendage. Increasing experience has improved overall procedural safety and ease while simultaneously reducing device related complication rates. Furthermore, increasing recognition of the non-mechanical advantages of this procedure has led to further interest in its utility for further indications beyond the prevention of thromboembolic complications. In this review, we present a comprehensive overview of the evolution of left atrial appendage occlusion, commercially available devices and the role of this modality in the current management of AF. We also provide a brief outline of the landmark trials supporting this approach as well as the ongoing research and future prospects of left atrial appendage occlusion.

The use of cardiac computed tomography angiography in the assessment of percutaneous left atrial appendage closure - Review and experts recommendations endorsed by the Société française d'imagerie cardiaque et vasculaire diagnostique et interventionnelle

Atrial fibrillation is the most common cause of arrhythmia which is responsible for over 15% of ischemic strokes, most of these being secondary to migration of a left atrial appendage (LAA) thrombus. In patient with contraindication to anticoagulant therapy, percutaneous closure system placement may be indicated. Cardiac computed tomography (CT) angiography plays a central role in the initial assessment as well as in the follow-up. The purpose of the pre-implantation cardiac CT angiography is to evaluate the anatomy of the LAA in order to select the most suitable prosthesis and check for any contraindication to device implantation. Image analysis is divided into four steps that include analysis of the approach; search for a thrombus in the LAA; investigation of the anatomy of the LAA (morphology of the LAA, dimensions of the LAA and choice of device) and cardiac and thoracic assessments. Follow-up involves CT examination to check for correct placement of the device and to detect any complications. On the basis of the results of currently available published research, a panel of experts has issued recommendations regarding cardiac CT angiography prior to percutaneous LAA closure device placement, which were further endorsed by the Société française d'imagerie cardiaque et vasculaire diagnostique et interventionnelle (SFICV).

Feasibility and safety of left atrial appendage occlusion guided by procedural fluoroscopy only: A pilot study

BACKGROUND

Left atrial appendage occlusion (LAAO) is usually performed via the guidance of procedural transesophageal echocardiography (TEE) companied by general anesthesia (GA).

OBJECTIVE

To investigate the feasibility and safety of LAAO guided by procedural fluoroscopy only.

METHODS

The patients eligible for LAAO were enrolled into the current study and received implantation of either Watchman device or LAmbre device. The procedure was carried out with procedural fluoroscopy only and no companied GA; the position, shape, and leakage of the device were assessed by contrast angiography. TEE was performed after 3-month follow-up to evaluate the thrombosis, and leakage of device.

RESULTS

Ninety-seven patients with atrial fibrillation (AF) with either Watchman device (n = 49) or LAmbre device (n = 48) were consecutively enrolled. Watchman device group was of lower CHA₂ DS₂ -VASc and HAS-BLED scores compared with LAmbre device groups (p < .05); the two groups had similar distributions of other baseline characteristics (p > .05), including procedural success rate (98.0% vs. 97.9%), mean procedure time, mean fluoroscopy time, total radiation dose, contrast medium dose, percentage of peri-device leakage. Pericardial effusions requiring intervention occurred in two of the Watchman group. TEE follow-up found no patient with residual leakage ≥5 mm at 3 months and no device related thrombosis (DRT). During the 22.0 ± 11.1 months follow-up, two patients experienced ischemic stroke.

CONCLUSIONS

LAAO with the procedural imaging of fluoroscopy only exhibited the promising results of efficacy and safety. A prospective randomized multicenter study would be required to verify the observations in this study.

Left atrial appendage occlusion in chicken-wing anatomies: Imaging assessment, procedural, and clinical outcomes of the "sandwich technique"

OBJECTIVES

To describe imaging assessment, procedural and follow-up outcome of patients undergoing left atrial appendage (LAA) occlusion (LAAO) using a "sandwich" technique.

BACKGROUND

The presence of a LAA with chicken wing morphology constitutes a challenge that sometimes requires specific occlusion strategies like the "sandwich" technique. However, procedural and follow-up data focusing on this implanting strategy is scarce.

METHODS

This multicenter study collected individual data from eight centers between 2012 and 2019. Consecutive patients with chicken-wing LAAs defined as an early (<20 mm from the ostium) and severe bend (>90°) who underwent LAAO with Amplatzer devices and using the "sandwich" technique were included in the analysis.

RESULTS

Overall, 190 subjects were enrolled in the study. Procedures were done with the Amulet device (85%) and the Amplatzer Cardiac Plug (15%). Successful implantation was achieved in 99.5% with ≤1 partial recapture in 80% of cases. Single (46.2%) and dual antiplatelet therapy (39.4%) were the most used antithrombotic therapies after LAAO. In-hospital major adverse events rate was 1.5% with no deaths. One patient (0.5%) had cardiac tamponade requiring percutaneous drainage. With a mean follow-up of 19.6 ± 14.8 months, the mortality and stroke rates were 7.7%/year and 2.5%/year, respectively. Follow-up transesophageal echocardiography (TEE) at 2-3 months showed device-related thrombosis in 2.8% and peri-device leak ≥3 mm in 1.2% of patients.

CONCLUSIONS

In a large series of patients with chicken wing LAA anatomies undergoing LAAO, the use of the "sandwich" technique was feasible and safe. Preprocedural imaging was a key-factor to determine specific measurements.

Impact of individual stroke risk on outcome after Amplatzer left atrial appendage closure in patients with atrial fibrillation

OBJECTIVES

To investigate periprocedural and long-term outcome of left atrial appendage closure (LAAC) using Amplatzer occluders with respect to individual pre-procedural stroke risk.

BACKGROUND

LAAC is a proven strategy for prevention from stroke and bleeding in patients with nonvalvular atrial fibrillation not amenable to oral anticoagulation. Whether individual pre-procedural stroke risk may affect procedural and long-term clinical outcome after LAAC is unclear.

METHODS

Multicenter study of consecutive patients who underwent Amplatzer-LAAC. Using pre-procedural CHADS₂ score, outcomes were compared between a low (0-2 points) and a high stroke risk group (3-6 points).

RESULTS

Five hundred consecutive patients (73.9 ± 10.1 years) who underwent Amplatzer-LAAC. Two hundred and forty eight had preprocedural CHADS₂ score ≤ 2 points (low-risk group) and the remaining 252 patients had 3-6 points (high-risk group). Periprocedural complication rates (6.0% vs. 5.6%, p = .85), procedural success (LAAC without major periprocedural or device-related complications or major para-device leaks: 89.4% vs. 87.9%, p = .74), and 30-day-mortality (2.4% vs. 2.6%, p = .77) were comparable. After 1,346 patient-years (PY), the long-term composite efficacy endpoint (stroke, systemic embolism, cardiovascular, and unexplained death) was reached in 23/653 (3.5/100 PY) versus 52/693 (7.5/100 PY); HR = 2.13; 95%-CI, 1.28-3.65, p = .002) with stroke rates 67% and 68% lower than anticipated by preprocedural CHADS₂ score. Combined safety endpoint (major periprocedural complications and major, life-threatening or fatal bleedings) occurred in 22/653 (3.4/100 PY) versus 28/693 (4.0/100 PY); HR = 1.20; 95%-CI, 0.66-2.20, p = .52).

CONCLUSIONS

Compared with patients at low risk of stroke, LAAC with Amplatzer devices is associated with similar safety and efficacy in high-risk patients in our study.

Device-Related Thrombus After Left Atrial Appendage Closure: Data on Thrombus Characteristics, Treatment Strategies, and Clinical Outcomes From the EUROC-DRT-Registry

[Figure: see text].

Percutaneous Left Atrial Appendage Occlusion: An Emerging Option in Patients with Atrial Fibrillation at High Risk of Bleeding

Atrial fibrillation (AF) is a common cardiac arrhythmia with an estimated prevalence of 1% in the general population. It is associated with an increased risk of ischemic stroke, silent cerebral ischemia, and cognitive impairment. Due to the blood flow stasis and morphology, thrombus formation occurs mainly in the left atrial appendage (LAA), particularly in the setting of nonvalvular AF (NVAF). Previous studies have shown that >90% of emboli related to NVAF originate from the LAA, thus prevention of systemic cardioembolism is indicated. According to the current guidelines, anticoagulant therapy with direct oral anticoagulants (DOACs) or vitamin K antagonists (VKAs), represents the standard of care in AF patients, in order to prevent ischemic stroke and peripheral embolization. Although these drugs are widely used and DOACs have shown, compared to VKAs, non-inferiority for stroke prevention with significantly fewer bleeding complications, some issues remain a matter of debate, including contraindications, side effects, and adherence. An increasing number of patients, indeed, because of high bleeding risk or after experiencing life-threatening bleedings, must take anticoagulants with extreme caution if not contraindicated. While surgical closure or exclusion of LAA has been historically used in patients with AF with contradictory results, in the recent years, a novel procedure has emerged to prevent the cardioembolic stroke in these patients: The percutaneous left atrial appendage occlusion (LAAO). Different devices have been developed in recent years, though not all of them are approved in Europe and some are still under clinical investigation. Currently available devices have shown a significant decrease in bleeding risk while maintaining efficacy in preventing thromboembolism. The procedure can be performed percutaneously through the femoral vein access, under general anesthesia. A transseptal puncture is required to access left atrium and is guided by transesophageal echocardiography (TEE). Evidence from the current literature indicates that percutaneous LAAO represents a safe alternative for those patients with contraindications for long-term oral anticoagulation. This review summarizes scientific evidences regarding LAAO for stroke prevention including clinical indications and an adequate patient selection.

Evidence and uncertainties in the management of atrial fibrillation in older persons

INTRODUCTION

Atrial fibrillation (AF) is the most common cardiac sustained arrhythmia, whose incidence and prevalence increase with age, representing a significant burden for health services in western countries. Older people contribute to the vast majority of patients affected from AF.

EVIDENCE ACQUISITION

Although oral anticoagulant therapy represents the cornerstone for the prevention of ischemic stroke and its disabling consequences, several other interventions - including left atrial appendage occlusion (LAAO), catheter ablation (CA) of AF, and rhythm control strategy (RCS) - have proved to be potentially effective in reducing the incidence of AF-associated clinical complications. Scientific literature focused on the three items will be discussed.

EVIDENCE SYNTHESIS

Practical treatment of older AF patients is presented, including approach and management of patients with geriatric syndromes, selection of the most appropriate individualized drug treatment, clinical indications and potential clinical benefit of LAAO and CA in selected older AF patients.

CONCLUSIONS

Older people carry the greatest burden of AF in real world practice. Within a shared decision making process, the patient centered approach need to be put in the context of a comprehensive assessment, in order to gain maximal net clinical benefit and avoid futility or harm.

Pulmonary ridge coverage and device-related thrombosis after left atrial appendage occlusion

AIMS

The aim of this study was to evaluate the impact of pulmonary ridge (PR) coverage on both clinical and imaging follow-up outcomes in patients undergoing left atrial appendage occlusion (LAAO).

METHODS AND RESULTS

The study included consecutive patients with non-valvular atrial fibrillation who underwent LAAO with disc and lobe devices. Patients were classified into two groups according to the PR coverage. A total of 147 patients were included. Among these, the PR was covered in 109 (74%) and uncovered in 38 (26%). Successful implantation was achieved in 98.6%. No differences in procedural outcomes were observed between the groups. The rate of procedural major adverse events was 3% (only major bleedings and/or vascular access complications). No device embolisation, cardiac tamponade or in-hospital mortality was observed. After a mean follow-up of 1.77±2.2 years, the annualised ischaemic stroke and major bleeding rate was 1.3%/year and 6.5%/year, respectively, without differences between groups. At follow-up, patients with a covered PR presented a lower incidence of device-related thrombosis (DRT) (1%) than those with an uncovered PR (27%); p<0.001. In multivariable analysis, the presence of PR coverage emerged as an independent predictor of DRT.

CONCLUSIONS

Pulmonary ridge coverage was associated with a lower incidence of DRT after LAAO. Procedural and follow-up clinical outcomes did not differ between covered PR and uncovered PR patients.

Why Follow-up Examinations After Left Atrial Appendage Closure Are Important: Detection of Complications During Follow-up and How to Deal with Them

PURPOSE OF REVIEW

Device-related thrombus (DRT) formation and incomplete left atrial appendage closure (LAAC) are the two major complications that can occur after LAAC and can potentially limit the success of such a procedure. This review discusses the incidence, clinical and/or prognostic significance, detection methods, treatment options, and potential strategies to prevent these complications.

RECENT FINDINGS

It has recently been proven that the presence of a DRT represents an independent predictor for ischemic stroke after LAAC. Continued need for anticoagulation due to incomplete LAAC is clinically relevant to the patient. The appearances of a DRT or an incompletely closed LAA after a LAAC procedure are not rare complications. Due to the clinical and/or prognostic significance of these complications, it is important to detect them in a timely manner during follow-up by using the appropriate diagnostic imaging techniques. Since a DRT is associated with an increased risk of stroke, the therapy should be aggressive. In the case of incomplete LAA closure, an additional closure device may be used to complete occlusion and avoid lifelong anticoagulation therapy.

Left atrial appendage occlusion with the Amulet device: to tug or not to tug?

PURPOSE

Left atrial appendage occlusion (LAAO) involves a "tug test," in which implanters pull on the device delivery cable to ensure stable occluder placement. The aim of this study was to evaluate the recommendation to perform the tug test, by comparing forces exerted on the device during deployment and subsequent tug test. A secondary objective was to simulate forces experienced on left atrial appendage tissue by placement of a 20-mm device.

METHODS

The AMPLATZER™ Amulet™ device was used for occlusion. A force transducer recorded forces in the delivery cable during deployment and tug test in 23 patients. Four patients were excluded due to improper transducer placement or technical errors in data collection. For a 20-mm device, the force imparted on the circumferential contact with left atrial appendage wall tissue was simulated in a computational model, using the measured externally applied forces as inputs.

RESULTS

For devices < 25-mm in diameter, disc deployment force (mean ± standard deviation) was 1.72 ± 0.43 N, and tug force was 1.01 ± 0.59 N. For devices ≥ 25 mm in diameter, disc deployment force was 2.96 ± 0.57 N, and tug force was 1.04 ± 0.24 N. The increase in disc deployment force compared with tug test force was statistically significant for small devices (< 25 mm; p = 0.049) and large devices (≥ 25 mm; p < 0.001).

CONCLUSIONS

Increased force applied on the AMPLATZER™ Amulet™ device during disc deployment compared with during tug test was statistically significant, suggesting that the tug test is redundant in most cases for checking device stability.

Impact of left atrial appendage closure on circulating microvesicles levels: The MICROPLUG study

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Left atrial appendage occlusion with the Amplatzer Amulet: update on device sizing

PURPOSE

The present paper analyzes the role of different imaging modalities for left atrial appendage (LAA) assessment and the recommended specific measurements to improve device selection with regard to the Amulet device.

BACKGROUND

Morphological LAA assessment is one of the pivotal factors to achieve proper LAA sealing and potentially reduce the risk of complications by minimizing manipulation inside the appendage.

METHODS

Eight experienced physicians in LAAO were asked to contribute in the preparation of a device sizing consensus manuscript after comprehensive assessment of previous published data on LAA imaging/measurement.

RESULTS

LAA morphology is often complex and requires more detailed spatial resolution and 3-dimensional assessments to reduce the risk of mis-sizing. Traditionally, upsizing of devices based upon the largest measured LAA diameters have been used. However, this may lead to oversizing in markedly elliptical appendages. Thus, when 3D imaging modalities are available, utilizing the LAA mean diameters might be a better alternative. Operators should also note the systematic biases in differences in measurements obtained with different imaging modalities, with CT giving the largest measurements, followed by 3D-TEE, and then 2D-TEE and angiography. In fact, for 2D imaging techniques (2D-TEE and angiography), LAA diameters tend to be underestimated, and therefore, LAA largest diameters seem to be still the best option for device sizing. Some specific anatomies such as proximal chicken-wing or conic LAAs may require different measurements and implantations to achieve implant success.

CONCLUSIONS

In conclusion, LAA mean diameters might be a better alternative to largest diameters when 3D imaging modalities are available.

Left Atrial Appendage Closure: Technical Considerations of Endocardial Closure

Left atrial appendage closure (LAAC) is a safe and effective therapy for the prevention of stroke in patients with nonvalvular atrial fibrillation and high bleeding risk with oral anticoagulants. Multimodality imaging with transesophageal echocardiography and computed tomography angiography to define the anatomy and its implications on endocardial exclusion is becoming increasingly important. The only LAAC device currently approved for clinical use in the United States is the WATCHMAN device. Systematic assessment of the transseptal crossing site, left atrial appendage anatomy, adequate device size selection, and device postdeployment evaluation is essential for the safety and efficacy of the procedure.

Anatomic Considerations for Epicardial and Endocardial Left Atrial Appendage Closure

Left atrial appendage closure is an increasingly used means of achieving thromboprophylaxis in atrial fibrillation, particularly in patients with contraindications to anticoagulation. Left atrial appendage anatomy is highly variable, and preprocedural imaging is critical to choosing the correct device and approach for left atrial appendage closure. This article reviews the common endocardial and epicardial closure systems, including anatomic considerations, advantages and disadvantages, as well as complications to be avoided.

Left Atrial Appendage Closure: Prevention and Management of Periprocedural and Postprocedural Complications

Left atrial appendage closure (LAAC) is noninferior to oral vitamin K antagonist therapy for the reduction of nonvalvular atrial fibrillation-related stroke risk. Currently, the procedure is most widely accepted in patients who cannot tolerate oral anticoagulants. This patient population is generally comorbid, making any reduction in procedural complications paramount. LAAC has important complications described in the periprocedural and postprocedural periods. The prevention and management of complications regarding vascular access, transseptal puncture, pericardial effusion, device embolization, stroke, air embolusperidevice leak, device-related thrombus and device erosion/ late pericardial effusion are discussed.

Intracardiac Versus Transesophageal Echocardiographic Guidance for Left Atrial Appendage Occlusion: The LAAO Italian Multicenter Registry

OBJECTIVES

This study sought to evaluate the feasibility, safety, and efficacy of intracardiac echocardiography (ICE)-guided versus transesophageal echocardiography (TEE)-guided left atrial appendage occlusion (LAAO) by the use of Amplatzer Cardiac Plug or Amulet devices included in a large Italian registry.

BACKGROUND

TEE is widely used for LAAO procedure guidance. ICE may be a potential alternative imaging modality in LAAO.

METHODS

Data from 604 LAAO procedures performed in 16 Italian centers were reviewed. ICE-guided LAAO was performed in 187 patients, whereas TEE was used in 417 patients. Procedural success was defined as LAAO without occurrence of pericardial tamponade, stroke, systemic embolism with end organ damage, major bleeding, and device embolization. Stroke, transient ischemic attack, major bleeding, overall and cardiovascular death were analyzed.

RESULTS

CHA₂DS₂-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism, vascular disease, age 65 to 74 years, sex category) and HAS-BLED (hypertension, abnormal renal and liver function, stroke, bleeding, labile international normalized ratio, elderly, drugs or alcohol) scores were similar between the ICE and TEE groups. TEE implied lower procedural (delta 12 min) and fluoroscopy time (delta 5 min) when compared with ICE. Procedural success was similarly high (≥94%) between the TEE and ICE groups with a complication rate of 6.5% for TEE versus 4.2% for ICE (odds ratio: 1.468; 95% confidence interval: 0.681 to 3.166; p = 0.327). At median follow-up of 451 days (interquartile range: 162 to 899 days), the rate of cerebral ischemic events was similar between TEE-guided and ICE-guided procedures.

CONCLUSIONS

ICE-guided LAAO by means of Amplatzer devices may represent a second alternative imaging modality after an appropriate learning curve and bearing in mind that pre-procedural computed tomography imaging is mandatory. When comparing ICE with TEE, TEE remains the gold standard.

Prevalence of extra-appendage thrombosis in non-valvular atrial fibrillation and atrial flutter in patients undergoing cardioversion: a large transoesophageal echo study

AIMS

The aim of our study was to evaluate the prevalence of left atrial cavity and appendage thrombosis in patients undergoing cardioversion for non-valvular atrial tachyarrhythmias. In persistent atrial tachyarrhythmias, 90% of thromboses are reported to be located inside the left atrial appendage. This prevalence refers to old studies and meta-analysis in a mixed population of valvular and non-valvular atrial fibrillation. Left atrial cavity thrombosis in non-valvular atrial fibrillation has not been investigated recently in large-scale studies.

METHODS AND RESULTS

A total of 1,420 consecutive adult patients with paroxysmal or persistent atrial tachyarrhythmias, candidates to cardioversion, who opted for a transoesophageal echocardiography-guided strategy, were enrolled in the study. Mitral stenosis, rheumatic valve disease and mechanical prostheses were excluded. In total there were 91 thrombi in 87 patients with a prevalence of 6.13% (87/1,420). Patients with left atrial thrombosis had predisposing clinical and echo characteristics (heart failure, lower ventricular function and higher atrial volume). Except for one case in which the thrombus was located in the left atrial cavity (0.07%), and three in the right appendage, all thromboses were detected in the left atrial appendage.

CONCLUSIONS

Extra-appendage thrombosis is a very rare finding in non-valvular persistent and paroxysmal atrial tachyarrhythmias and, when present, a left appendage thrombus is usually concomitant.

Left Atrial Appendage Occlusion: The Current Device Landscape and Future Perspectives

Since the first percutaneous left atrial appendage occlusion (LAAO), many studies have shown the safety and efficacy of this technique to prevent embolic strokes in nonvavular atrial fibrillation. The design, characteristics, and clinical data of the most frequently used devices for LAAO are reviewed, including the Amplatzer cardiac plug and Amulet (Abbott Vascular), the Watchman (Boston Scientific), and the LARIAT device (SentreHEART). Similarly, newer closer devices, such as Ultraseal (Cardia), LAmbre (Lifetech), and Coherex WaveCrest (Johnson & Johnson), are also discussed. Finally, new technologies still in the stage of preclinical study or in the initial clinical experience are also reviewed.

Anatomy and Physiologic Roles of the Left Atrial Appendage: Implications for Endocardial and Epicardial Device Closure

The left atrial appendage has been implicated as a major nidus for thrombus formation, particularly in atrial fibrillation. This discovery has prompted substantial interest in the development of left atrial appendage exclusion devices aimed at decreasing systemic thromboembolism risk. Its deceptively simple appearance belies the remarkable complexity that characterizes its anatomy and physiology. We highlight the key anatomic features and variations of the left atrial appendage as well as its relationships with surrounding structures. We also summarize crucial anatomic factors that should be taken into account by the interventional cardiologist when planning for or performing left atrial appendage exclusion procedures.