Ellis, Christopher R.

Abstract Since its introduction in 2002, left atrial appendage closure (LAAC) has rapidly expanded as an alternative to anticoagulation in patients with atrial fibrillation at high risk of stroke. Harmonized processes for data collection, analysis, and reporting in LAAC trials are essential to enhance research quality and improve clinical practice. The Left Atrial Appendage Academic Research Consortium (LAARC) initiative is an independent collaboration of academic research organizations, cardiology and neurology experts, clinical trialists, and regulatory authorities from the USA, Europe, and Asia. The consortium engaged clinical experts, regulators—including the US Food and Drug Administration (FDA), European Notified Bodies, and Japan’s Pharmaceuticals and Medical Devices Agency (PMDA)—and industry leaders to define standardized study elements and endpoints for LAAC trials. Key considerations included alignment with prior Academic Research Consortium initiatives, procedural and mechanistic insights, and clinical relevance. Consensus definitions were proposed for mortality, stroke, bleeding, and device performance, along with composite endpoints for safety and effectiveness. The proposed LAARC consensus definitions aim to standardize endpoint reporting, improve comparability across studies, and support regulatory and clinical trial applications for this evolving therapy through broad dissemination in the peer-reviewed literature.

Importance Left atrial appendage occlusion (LAAO) is used in patients with contraindications to oral anticoagulation, who are at increased risk for major bleeding (MB). Objective To evaluate the incidence, predictors, management, and clinical outcomes of MB after LAAO in the Amulet IDE trial. Design, Setting, and Participants The randomized clinical Amulet IDE trial enrolled patients from 2016 through 2019 with 5-year follow-up. Procedures were performed at specialized LAAO centers. Of 1878 randomized patients (1:1 Amulet vs Watchman), 1833 underwent attempted LAAO implantation. These data were analyzed from May 2025 through November 2025. Main Outcomes and Measures Pooled (Amulet and Watchman) patients with vs without MB (Bleeding Academic Research Consortium [BARC] score ≥3: overt bleeding with transfusion and ≥3 g/dL hemoglobin drop) were compared. Results This study included a total of 1833 patients (57.7% male and 42.3% female; mean [SD] age, 75.8 [7.5] years). MB occurred in 331 patients (18.1%) over 5 years (annualized rate 5.9% per year). Patients with MB were older (76.8 vs 74.7 years) and had higher CHA 2 DS 2 -VASc (4.8 vs 4.6) and HAS-BLED (3.4 vs 3.2) scores, as well as greater prevalence of diabetes (38.7% vs 34.1%), prior MB (45.3% vs 28.0%), and kidney disease (9.4% vs 4.5%). MB risk was highest in the first 6 months after LAAO (20.5% per year), then decreased to 3.9% per year through 5 years. Most MB events were nonprocedural (88.8%) with gastrointestinal bleeding accounting for 252 of 438 events. Independent predictors of MB included increasing age (hazard ratio [HR], 1.04; 95% CI, 1.02-1.06), female sex (HR, 1.25; 95% CI, 1.01-1.56), diabetes (HR, 1.26; 95% CI, 1.01-1.58), prior MB (HR, 1.93; 95% CI, 1.55-2.40), and kidney disease (HR, 2.15; 95% CI, 1.48, 3.12). At first MB event, 47.1% of patients were not receiving antithrombotic therapy and 92 patients had recurrent events. Patients with MB had significantly higher rates of the composite of stroke, systemic embolism, or cardiovascular death (32.5% vs 18.0%; P < .001), driven by higher stroke (14.7% vs 6.6%) and cardiovascular death (24.4% vs 12.9%) rates. All-cause mortality was also higher (49.2% vs 25.4%; P < .001). MB was fatal (BARC score of 5) in 25 patients (1.4%). Conclusions and Relevance In this study, MB was common in this high-risk population and largely related to underlying patient factors. Early MB risk was highest 6 months post-LAAO, then dropped considerably. Most events were gastrointestinal and occurred even in patients on minimal or no antithrombotic therapy. MB after LAAO was strongly associated with increased stroke and mortality. Trial Registration ClinicalTrials.gov Identifier: NCT02879448

Abstract Background Thromboembolic stroke risk remains a clinical challenge in cardiac amyloidosis (CA) patients with atrial fibrillation because of the increased prevalence of left atrial appendage thrombi irrespective of CHA2DS2-VASc score and a higher prevalence of factors that increase the risk of bleeding with anticoagulation. Left atrial appendage closure (LAAC) is an effective option in patients with atrial fibrillation and high bleeding risk; however, data describing a LAAC strategy for stroke prevention in patients with CA is limited. Among non-CA patients, procedural success and serious complication rates are around 98% and 3% respectively. Purpose In this multicenter retrospective study, we aimed to investigate whether left atrial appendage closure (LAAC) could reduce the risk of bleeding complications and ischemic cerebrovascular events in patients with CA. Methods In an international multi-center retrospective study, patients with CA that underwent LAAC were included. The diagnosis of CA was established on the basis of histologic confirmation or advanced multimodality cardiac imaging as per current consensus statements. Results A total of 28 patients (93% male; 87% ATTR-CA; 13% AL-CA; mean age 80 years) met inclusion criteria. At baseline, mean CHA2DS2-VASc and HAS-BLED scores were 4 and 3 respectively, mean left ventricular ejection fraction was 50%, and mean indexed left atrial volume was 58 mL/m2. 21% of patients had a prior history of ischemic stroke, 14% prior history of hemorrhagic stroke, 7% prior transient ischemic attack, and 54% had a prior history of major or minor bleeding. Procedural success was achieved in 26 patients (93%) with procedural complications occurring in 2 patients (vascular access site bleeding and cardiac tamponade). Regarding in-hospital and follow-up complications, 0% ischemic stroke, 0% hemorrhagic stroke, and major or minor bleeding in 4% of patients. During follow up, device thrombosis occurred in only 1 patient. Conclusion LAAC is a feasible and effective alternative to anticoagulation in patients with CA and excessive bleeding risk, with procedural success and complication rates similar to reported studies of non-CA patients.

Background The PINNACLE FLX (Protection Against Embolism for Non‐valvular AF [Atrial Fibrillation] Patients: Investigational Device Evaluation of the Watchman FLX LAA [Left Atrial Appendage] Closure Technology) trial evaluated the safety and efficacy of a next‐generation left atrial appendage closure device (WATCHMAN FLX; Boston Scientific, Marlborough, MA). At 1 year, the study met the primary end points of safety and anatomical efficacy/appendage closure. This final report of the PINNACLE FLX trial includes the prespecified secondary end point of ischemic stroke or systemic embolism at 2 years, also making it the first report of 2‐year outcomes with this next‐generation left atrial appendage closure device. Methods and Results Patients with nonvalvular atrial fibrillation with CHA 2 DS 2 ‐VASc score ≥2 (men) or ≥3 (women), with an appropriate rationale for left atrial appendage closure, were enrolled to receive the left atrial appendage closure device at 29 US centers. Adverse events were assessed by an independent clinical events committee, and imaging was assessed by independent core laboratories. Among 395 implanted patients (36% women; mean age, 74 years; CHA 2 DS 2 ‐VASc, 4.2±1.5), the secondary efficacy end point of 2‐year ischemic stroke or systemic embolism was met, with an absolute rate of 3.4% (annualized rate, 1.7%) and an upper 1‐sided 95% confidence bound of 5.3%, which was superior to the 8.7% performance goal. Two‐year rates of adverse events were as follows: 9.3% all‐cause mortality, 5.5% cardiovascular death, 3.4% all stroke, and 10.1% major bleeding (Bleeding Academic Research Consortium 3 or 5). There were no additional systemic embolisms, device embolizations, pericardial effusions, or symptomatic device‐related thrombi after 1 year. Conclusions The secondary end point of 2‐year stroke or systemic embolism was met at 3.4%. In these final results of the PINNACLE FLX trial, the next‐generation WATCHMAN FLX device demonstrated favorable safety and efficacy outcomes.

AbstractBackgroundThough infrequent, incomplete left atrial appendage closure (LAAC) may result from residual leaks. Percutaneous closure has been described though data is limited.MethodsWe compiled a registry from four centers of patients undergoing percutaneous closure of residual leaks following LAAC via surgical means or with the Watchman device. Leak severity was classified as none (no leak), mild (1–2 mm), moderate (3–4 mm), or severe (≥5 mm). Procedural and clinical success was defined as the elimination of leak or mild residual leak at the conclusion of the procedure or follow‐up, respectively.ResultsOf 72 (age 72.2 ± 9.2 years; 67% male) patients, 53 had undergone prior LAAC using the Watchman device and 19 patients surgical LAAC. Mean CHADS2‐VA2Sc score was 4.0 ± 1.8. The median leak size was 5 mm, range: 2–13). A total of 13 received Amplatzer Vascular Plug‐II, 18 received Amplatzer Duct Occluder‐II and 40 patients received coils. One underwent closure using a 21 mm‐Watchman. Procedural success was 94%. Zero surgical and nine Watchman patients (13%) had a residual leak at procedural‐end (five mild, three moderate, and one severe)—only one patient had no reduction in leak size. Overall leak size reduction was 94%. Two (3%) had intraoperative pericardial effusion. There were no device embolizations, device‐related thrombi, or procedural deaths. Clinical success was maintained at 94%. Two had cerebrovascular accidents—at 2 days (transient ischemic attack) and 10 months postprocedure. Two had major bleeding outside the 30‐day periprocedural window.ConclusionPercutaneous closure of residual leaks following left atrial appendage closure is feasible and associated with good outcomes. The procedural risk appears to be satisfactory.

Background: Left atrial appendage (LAA) occlusion provides an alternative to oral anticoagulation for thromboembolic risk reduction in patients with nonvalvular atrial fibrillation. Since regulatory approval in 2015, the WATCHMAN device has been the only LAA closure device available for clinical use in the United States. The PINNACLE FLX study (Protection Against Embolism for Nonvalvular AF Patients: Investigational Device Evaluation of the Watchman FLX LAA Closure Technology) evaluated the safety and effectiveness of the next-generation WATCHMAN FLX LAA closure device in patients with nonvalvular atrial fibrillation in whom oral anticoagulation is indicated, but who have an appropriate rationale to seek a nonpharmaceutical alternative. Methods: This was a prospective, nonrandomized, multicenter US Food and Drug Administration study. The primary safety end point was the occurrence of one of the following events within 7 days after the procedure or by hospital discharge, whichever was later: death, ischemic stroke, systemic embolism, or device- or procedure-related events requiring cardiac surgery. The primary effectiveness end point was the incidence of effective LAA closure (peri-device flow ≤5 mm), as assessed by the echocardiography core laboratory at 12-month follow-up. Results: A total of 400 patients were enrolled. The mean age was 73.8±8.6 years and the mean CHA 2 DS 2 -VASc score was 4.2±1.5. The incidence of the primary safety end point was 0.5% with a 1-sided 95% upper CI of 1.6%, meeting the performance goal of 4.2% ( P <0.0001). The incidence of the primary effectiveness end point was 100%, with a 1-sided 95% lower CI of 99.1%, again meeting the performance goal of 97.0% ( P <0.0001). Device-related thrombus was reported in 7 patients, no patients experienced pericardial effusion requiring open cardiac surgery, and there were no device embolizations. Conclusions: LAA closure with this next-generation LAA closure device was associated with a low incidence of adverse events and a high incidence of anatomic closure. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02702271.