Safety and Efficacy of Left Atrial Appendage Closure with the Amplatzer Cardiac Plug in Very High Stroke and Bleeding Risk Patients with Non-Valvular Atrial Fibrillation

Percutaneous left atrial appendage closure in patients with gastrointestinal bleeding associated with oral anticoagulants

INTRODUCTION

Percutaneous left atrial appendage closure (LAAC) has shown non-inferiority compared to oral anticoagulation (OAC) in preventing atrial fibrillation (AF)-related stroke. The objective of this study was to assess whether LAAC reduces the incidence of gastrointestinal bleeding (GIB) and/or chronic anaemia associated with OAC, as well as the consumption of healthcare resources.

MATERIALS AND METHODS

Prospective, single-center study from 2016 to 2022, LAAC was performed. Clinical, analytical and healthcare resource consumption data were collected (endoscopies, blood transfusions, hospital admissions) prior and 6 months after LAAC.

RESULTS

43 patients were included, with an average age of 77.6 years. LAAC indication was upper, low and obscure GIB in 7 (16%), 8 (19%) and 28 patients (65%) respectively. GIB source was intestinal angiodysplasias in 27 patients (63%), occult origin in 12 (28%), and others (antral vascular ectasia, portal hypertension gastropathy, etc.) in 4 patients (9%). The mean number of packed red blood cells per patient before LAAC was (mean ± SD) 7.29 ± 5 vs 0.42 ± 1.3 (p < 0.001); endoscopic procedures were 4.34 ± 2.85 vs 0.27 ± 0.76 (p < 0.001); and hospitalizations 2.67 ± 2.14 vs 0.03 ± 0.17 (p < 0.001), with a hospital stay of 21.5 ± 17.3 vs 0.09 ± 0.5 days (p < 0.001) at 6 months post-intervention. Haemoglobin value increased from 8.1 ± 1.2g/dl to 12.4 ± 2.2g/dl (p < 0.001) at 6 months. No thromboembolic events were registered during a median follow-up of 16.6 months (range 6-65).

CONCLUSIONS

LAAC could be a safe and effective alternative to OAC in patients with non-valvular AF presenting significant, recurrent or potentially unresolvable GIB. This intervention also leads to important savings in the consumption of healthcare resources.

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.

Meta-analysis of postoperative antithrombotic therapy after left atrial appendage occlusion

Objective

This meta-analysis explored the safety and effectiveness of different anticoagulant regimens after left atrial appendage occlusion (LAAO).

Methods

Databases, such as PubMed, MEDLINE, EMBASE, Web of Science, and Cochrane Library, were searched to identify eligible studies according to the inclusion criteria. The incidences of events, including device-related thrombus (DRT) formation, stroke, systemic thromboembolism, bleeding, cardiovascular mortality, and all-cause mortality, were analyzed using R version 3.2.3.

Results

The screening retrieved 32 studies, including 36 study groups and 4,474 patients. The incidence of outcomes after LAAO was calculated via meta-analysis. In the subgroup analysis, the rates of DRT formation, cardiovascular mortality, and all-cause mortality were significantly different among different antithrombotic methods. Single antiplatelet therapy was associated with the highest rate of adverse events, followed by dual antiplatelet therapy (DAPT). Vitamin K antagonists (VKAs) and new oral anticoagulants (NOACs) carried lower rates of adverse events.

Conclusions

Anticoagulant therapy had better safety and efficacy than antiplatelet therapy. Thus, for patients with nonabsolute anticoagulant contraindications, anticoagulant therapy rather than DAPT should be actively selected. NOACs displayed potential for further development, and these treatments might represent alternatives to VKAs in the future.

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.

Short-Term Antiplatelet Versus Anticoagulant Therapy After Left Atrial Appendage Occlusion: A Systematic Review and Meta-Analysis

OBJECTIVES

The aim of this study was to compare bleeding, thromboembolic, device-related thrombus (DRT), and all-cause mortality events between patients treated with short-term oral anticoagulation (OAC) and those treated with short-term antiplatelet therapy (APT) following left atrial appendage occlusion (LAAO).

BACKGROUND

Short-term OAC is recommended for patients following LAAO. However, in practice many patients receive APT rather than OAC because of excessive bleeding risk. However, the safety and efficacy of APT compared with OAC have been debated.

METHODS

A search was conducted of databases for studies comparing OAC with APT following LAAO. The outcomes of interest were all-cause stroke, major bleeding, DRT, and all-cause mortality. Noncomparative studies were pooled into a single study to generate comparisons of the studies' outcomes. Effects measure were pooled using the random-effect model.

RESULTS

A total of 83 studies with 12,326 patients (APT, n = 7,900; OAC, n = 4,151) were included. Mean CHA2DS2-VASc and HAS-BLED scores were 4.1 ± 1.6 and 3.0 ± 1.3, respectively. There were no significance differences between the APT and OAC groups with regard to stroke (risk ratio [RR]: 1.04; 95% confidence interval [CI]: 0.54 to 1.98; p = 0.91; I2 = 31%), major bleeding (RR: 1.12; 95% CI: 0.68 to 1.84; p = 0.65; I2 = 53%), DRT (RR: 1.33; 95% CI: 0.74 to 2.39; p = 0.33; I2 = 36%), and all-cause mortality (RR: 1.29; 95% CI: 0.40 to 4.09; p = 0.18; I2 = 36%). These findings persisted in multiple secondary analyses: 1) excluding studies that reported no events; 2) including comparative studies only; 3) excluding patients who were treated with single APT; and 4) removing one study at a time to assess the effect of each study on the overall effect size. There was also no difference in the studies' endpoints among patients who received different LAAO devices.

CONCLUSIONS

In a meta-analysis of observational data, there were no differences in the occurrence of stroke, major bleeding DRT, and all-cause mortality in patients treated with short-term OAC or APT following LAAO.

Percutaneous Left Atrial Appendage Closure: is there a Role in Valvular Atrial Fibrillation

Atrial fibrillation, a chronic and highly morbid cardiovascular condition which affects over 33 million people worldwide, can be broadly categorized as valvular vs non-valvular in etiology. However, definitions of valvular atrial fibrillation have varied widely in the literature, and there is no clear consensus definition to date. Historically, patients with atrial fibrillation in the setting of rheumatic mitral valve disease have constituted a particularly high risk group for cardioembolic stroke, and for this reason many contemporary trials of pharmaceutical and device therapies for atrial fibrillation have systematically excluded patients with valvular heart disease. Therefore, vitamin K antagonism remains the favored approach to mitigate stroke risk in valvular atrial fibrillation, and the optimal strategy to treat atrial fibrillation patients with valvular heart disease who cannot tolerate oral anticoagulation therapy is unknown. Recent trials have demonstrated an important role for percutaneous left atrial appendage occlusion devices in patients with non-valvular atrial fibrillation, but the role of these devices in patients with valvular atrial fibrillation is uncertain. Given the worldwide burden of valvular atrial fibrillation, future trials intended to clarify the role of percutaneous left atrial appendage closure devices in valvular atrial fibrillation should provide important insight for the care of millions of patients.

Outcome of left atrial appendage occlusion in high-risk patients

OBJECTIVE

Percutaneous left atrial appendage (LAA) occlusion can be an interventional alternative to oral anticoagulation for stroke prevention in patients with atrial fibrillation.

METHODS

We delivered LAA occlusion therapy using a standardised approach to patient referral, multidisciplinary team assessment, implant criteria, imaging and follow-up. We analysed patient characteristics, efficacy and safety of the implant procedure, and 12-month outcomes.

RESULTS

Of 143 referrals from October 2014 to December 2016, 83 patients (age 76±8years, 32.5% female, mean CHAD₂S₂-VASc score 4 ±1) were offered LAA occlusion. Eighty (95.3%) had previous major bleeding (intracranial in 59%). LAA occluder implantation with an Amulet device was successful in 82 (98.8%), with periprocedural major adverse events occurring in 5 (6.0%) patients (2 device embolisations including 1 death, 2 major bleeds). Cardiac imaging in 75 (94%) patients 2months following implant showed device-related thrombus in 1 case (1.3%) and minor (<5mm) device leaks in 13 (17.1%). Over a median 12-month follow-up, 3 (3.8%) ischaemic strokes, 2 (2.5%) haemorrhagic strokes and 5 (6.3%) major extracranial bleeds occurred. All-cause mortality was 10%, with most deaths (7, 87.5%) due to non-cardiovascular causes.

CONCLUSIONS

LAA occlusion may be a reasonable option for stroke prevention inhigh-risk patients with atrial fibrillation ineligible for anticoagulation. However, procedural complication rates are not insignificant, and patients remain at risk of serious adverse events and death even after successful implant.

Stroke Risk Factors, Genetics, and Prevention

Stroke is a heterogeneous syndrome, and determining risk factors and treatment depends on the specific pathogenesis of stroke. Risk factors for stroke can be categorized as modifiable and nonmodifiable. Age, sex, and race/ethnicity are nonmodifiable risk factors for both ischemic and hemorrhagic stroke, while hypertension, smoking, diet, and physical inactivity are among some of the more commonly reported modifiable risk factors. More recently described risk factors and triggers of stroke include inflammatory disorders, infection, pollution, and cardiac atrial disorders independent of atrial fibrillation. Single-gene disorders may cause rare, hereditary disorders for which stroke is a primary manifestation. Recent research also suggests that common and rare genetic polymorphisms can influence risk of more common causes of stroke, due to both other risk factors and specific stroke mechanisms, such as atrial fibrillation. Genetic factors, particularly those with environmental interactions, may be more modifiable than previously recognized. Stroke prevention has generally focused on modifiable risk factors. Lifestyle and behavioral modification, such as dietary changes or smoking cessation, not only reduces stroke risk, but also reduces the risk of other cardiovascular diseases. Other prevention strategies include identifying and treating medical conditions, such as hypertension and diabetes, that increase stroke risk. Recent research into risk factors and genetics of stroke has not only identified those at risk for stroke but also identified ways to target at-risk populations for stroke prevention.