Left Circumflex Fistula After Watchman Implantation: A Case Report of Left Atrial Appendage Closure Complication.

Left atrial appendage closure devices reduce the risk of stroke in patients with nonvalvular atrial fibrillation while avoiding the risks associated with therapeutic anticoagulation. This significant value comes with additional unique risks associated with device implantation or surgical closure. We discuss an uncommon complication of Watchman device (Boston Scientific) implantation wherein an asymptomatic fistulous connection developed between the left atrial appendage and the left circumflex artery. Additionally, we review other documented cases of left atrial appendage fistulas and current management approaches for iatrogenic fistulous connections associated with procedural left atrial appendage closure.

Embolized Watchman Removal With Modified Hangman Technique.

In this case report, we explore a novel technique to remove an embolized Watchman device (Boston Scientific) into the thoracic aorta endovascularly. The technique involves a wire + snare combination that is threaded through the metal struts of the Watchman. This combination technique along with the threading provides increased stability during removal and decreases the risk of the Watchman slipping from the devices and causing further embolization. Further work is required to elucidate the efficacy of this technique in other scenarios.

Gender differences in outcomes after left atrial appendage closure with Watchman FLX device: insights from the Italian-FLX registry.

Introduction: Recent studies have shown gender differences in cardiovascular outcomes after left atrial appendage closure (LAAC), highlighting different complication rates and adverse events, particularly in short-term assessments. As a result, there remains a significant knowledge gap on how these differences directly impact the efficacy and safety of LAAC procedures. The aim of this retrospective study was to investigate the clinical outcomes of LAAC in women and men using the Watchman FLX device. Methods: This retrospective, multicenter study analyzes gender-specific outcomes in 650 patients who underwent LAAC with the Watchman FLX device between March 2019 and May 2022, drawn from the ITALIAN-FLX registry. Results: The results show comparable rates of all-cause mortality, stroke, transient ischemic attack and major bleeding in men and women 12 months after the procedure. Notably, no significant gender differences were found for periprocedural complications. Conclusion: In conclusion, this study shows that LAAC with the Watchman FLX device has comparable clinical outcomes between genders at both short-term and long-term follow-up.

"The Failing Watchman": Recurrent Left Atrial Appendage Occlusion Device (LAAOD) Thrombus After Successful Initial Implantation.

A 79-year-old female with chronic atrial fibrillation was being treated with dabigatran (Pradaxa). Pradaxa was discontinued after a significant bleeding episode. A WATCHMAN device was successfully implanted and Pradaxa was started. A transesophageal echocardiogram (TEE) 49 days later showed a 3.6×2.2 cm clot overlying the device. Pradaxa was switched to Coumadin. Subsequent TEEs showed the complete resolution of the thrombus after five months on Coumadin. Coumadin was discontinued. Six months later, TEE showed a large mobile thrombus attached to the left atrial appendage occlusion device (LAAOD). The patient's hypercoagulable workup was negative. Due to recurrent thrombotic events, she was started on apixaban (Eliquis) due to a prior history of bleeding on Coumadin. She is currently on Eliquis with no further episodes of bleeding or device thrombus.

Comparative Profiles of the WATCHMAN™ and Amplatzer™ Cardiac Plug/Amplatzer™ Amulet™ Devices for Left Atrial Appendage Closure in Non-valvular Atrial Fibrillation: A Comprehensive Systematic Review and Meta-analysis.

Atrial fibrillation (AF) is a prevalent cardiac arrhythmia marked by irregular and frequent tachycardic rhythms in the atria, affecting 1%-2% of the general population. The WATCHMAN™ device from Boston Scientific (Marlborough, MA, USA) and the Amplatzer™ Amulet™ device from Abbott (Chicago, IL, USA) are two devices used globally for left atrial appendage closure (LAAC) in non-valvular AF. A systematic search was conducted in PubMed, the Cochrane Library, and Elsevier's ScienceDirect literature databases to identify studies comparing the WATCHMAN™ procedure with Amulet™ device implantation for LAAC in patients with AF. The analyses were conducted using the random-effects model. A total of 20 studies were identified, with 18 falling into the category of observational studies and 2 being randomized controlled trials. A total of 6310 participants were included in this meta-analysis, with 3198 individuals (50.68%) assigned to the WATCHMAN™ procedure group and 3112 individuals (49.32%) allocated to the Amplatzer™ Cardiac Plug (ACP) group. The analysis revealed a higher risk of stroke associated with the WATCHMAN™ technique (relative risk [RR], 1.14), albeit without statistical significance. Conversely, the WATCHMAN™ approach led to a significantly lower risk of cardiac death (RR, 0.44; P = .04). Notably, the risks of all-cause mortality (RR, 0.89; 95% confidence interval [CI], 0.73-1.08; I 2 = 0%; P = .25) and major bleeding (RR, 0.93; 95% CI, 0.65-1.33; I 2 = 31%; P = .70) were clinically reduced with the WATCHMAN™ procedure, although statistical significance was not achieved. Compared to Amulet™ device implantation, WATCHMAN™ device implantation decreased the risk of cardiac mortality, while the risks of stroke, systemic embolism, all-cause mortality, and major bleeding were not statistically significant.

Unforeseen and Immediate: A Case of a Post-Watchman Device-Related Thrombus.

Atrial fibrillation (AFib) is recognized as a risk factor linked to arterial thromboembolism stemming from blood clot formation in the left atrium, associated with increased morbidity and mortality. Most of these thrombi originate in the left atrial appendage (LAA). Oral anticoagulation (OAC) therapy can help mitigate this risk. LAA occlusion (LAAO) has emerged as an option for patients who cannot safely tolerate long-term OAC. Watchman is one of the commonly used devices with a favorable safety profile demonstrated in numerous studies. One of the most concerning complications of LAAO is device-related thrombus (DRT), which may form on the atrial side of the device and potentially lead to embolization. We present a rare case of immediate DRT formation following the deployment of a Watchman device in a 78-year-old male with persistent AFib. Despite appropriate periprocedural management, a thrombus was observed immediately post implantation. This case emphasizes the need for vigilant surveillance, prompt diagnosis, and therapeutic intervention to manage such complications. The patient was successfully managed with a heparin drip, leading to thrombus resolution. This report underscores the complexities of managing DRT and the importance of ongoing research to optimize outcomes for patients undergoing LAAO.

Transition from WATCHMAN generation-2.5 device to WATCHMAN FLX device for percutaneous left atrial appendage closure: Incidence and predictors of device-related thrombosis and short- to mid-term outcomes.

BACKGROUND: Patients with nonvalvular atrial fibrillation (AF) not suitable for long-term anticoagulant therapy undergo percutaneous left atrial appendage closure (LAAC) using the WATCHMAN device. The safety and efficacy of WATCHMAN-FLX (WM-FLX) compared with WATCHMAN-2.5 (WM-2.5), particularly in Asian populations, is unknown. METHODS: We evaluated the background, procedure, and clinical outcomes of 199 patients who underwent LAAC between September 2019 and December 2022 and compared WM-2.5 (72 patients) with WM-FLX (127 patients). RESULTS: The mean age was 76 years, with 128 men, and 100 had nonparoxysmal AF (non-PAF). The mean CHA2DS2-VASc, and HAS-BLED were 5.1, and 3.2 points, respectively. WM-FLX group demonstrated a shorter procedure time than WM-2.5 group (50 vs. 42 min, p = 0.001). The WM-FLX group demonstrated no procedural-related acute cardiac tamponade, which was significantly low (5.6% vs. 0%, p = 0.02), and a significantly higher rate of complete seal at 45-day (63% vs. 80%, p = 0.04). WM-FLX group had a significantly higher cumulative 1-year incidence of device-related thrombosis (DRT) than WM-2.5 group (3.4% vs. 7.0%, Log-rank p = 0.01). Univariate analysis identified two DRT risk factors in the WM-FLX group: non-PAF (odds ratio [OR] 7.72; 95% confidence interval [CI] 1.20-48.7; p = 0.04), and 35-mm device (OR 5.13; 95% CI 1.31-19.8; p = 0.02). CONCLUSIONS: WM-FLX significantly improved the procedural quality and safety of LAAC. However, DRT remains an important issue even in the novel LAAC device, being a hazard for patients with high DRT risk, such as having non-PAF and using 35-mm devices.

Incidence and temporal evolution of delayed peridevice leak after left atrial appendage closure.

BACKGROUND: Peridevice leak (PDL) after left atrial appendage closure (LAAC) portends adverse outcomes. OBJECTIVE: The purpose of this study was to assess the incidence, predictors, clinical implications, and temporal evolution of PDL after LAAC. METHODS: This single-center retrospective study included all patients who underwent LAAC with Watchman FLX and had no PDL detected at the time of implantation. The primary end point was the incidence of new PDL at initial imaging. The composite secondary end point included continued oral anticoagulation after initial imaging, device-related thrombus, stroke or transient ischemic attack, major bleeding, and need for PDL closure at longest follow-up. Temporal evolution of PDL was assessed in patients with available surveillance imaging. RESULTS: Of the 355 patients who completed imaging at 47 days (interquartile range [IQR] 44-50 days), 139 (39%) had new PDL with a mean leak size of 3.2 ± 1.4 mm (median 3.0 mm; IQR 2.0-4.0 mm; range 1.0-9.0 mm). Multiple deployment attempts and larger device size were positive predictors of PDL, while increased contrast volume administration was a negative predictor of PDL. The composite secondary end point occurred in 42 (30%) patients with PDL and 33 (15%) patients without PDL (P < .001). Of the 139 patients with PDL, 43 (31%) had surveillance imaging where the leak size regressed from 3.7 ± 1.8 mm at 46 days (IQR 44-51 days) to 1.7 ± 2.0 mm at 189 days (IQR 158-285 days) (P < .001). The leak size regressed in 33 (77%), remained stable in 4 (9%), and progressed in 6 (14%) cases. CONCLUSION: Despite design improvements, LAAC with Watchman FLX demonstrates a significant incidence of PDL with meaningful clinical implications. Regardless of initial size, most leaks regressed over time.

Retrieval of Embolized WATCHMAN® Flex Atrial Appendage Occlusion Device.

This case report documents the management of a 66-year old man with atrial fibrillation with recent placement of a WATCHMAN® Flex atrial appendage occlusion device. The patient presented with renal failure, abdominal pain, and difficulty walking 2 months after placement. The WATCHMAN® Flex device was found to have embolized to his abdominal aorta at the level of the renal arteries with associated thrombus. Extensive workup revealed reduced left ventricular cardiac function and decreased renal function, both of which were felt to be potentially reversible with device removal. The patient then underwent retrieval of the device and all associated thrombus via an open retroperitoneal approach. This case demonstrates a potential consequence of implanting devices such as an atrial appendage occlusion device and describes a technique for removal.

Management of cerebral amyloid angiopathy and atrial fibrillation: We are still far from precision medicine.

The use of anticoagulation therapy could prove to be controversial when trying to balance ischemic stroke and intracranial bleeding risks in patients with concurrent cerebral amyloid angiopathy (CAA) and atrial fibrillation (AF). In fact, CAA is an age-related cerebral vasculopathy that predisposes patients to intracerebral hemorrhage. Nevertheless, many AF patients require oral systemic dose-adjusted warfarin, direct oral anticoagulants (such as factor Xa inhibitors) or direct thrombin inhibitors to control often associated with cardioembolic stroke risk. The prevalence of both CAA and AF is expected to rise, due to the aging of the population. This clinical dilemma is becoming increasingly common. In patients with coexisting AF and CAA, the risks/benefits profile of anticoagulant therapy must be assessed for each patient individually due to the lack of a clear-cut consensus with regard to its risks in scientific literature. This review aims to provide an overview of the management of patients with concomitant AF and CAA and proposes the implementation of a risk-based decision-making algorithm.

Comparative Data of Procedural and Midterm Outcomes in Patients Who Underwent Percutaneous Left Atrial Appendage Closure Between the WATCHMAN FLX and WATCHMAN 2.5 Devices　- Insight From the OCEAN-LAAC Registry.

BACKGROUND: Limited data are available regarding clinical outcomes after percutaneous left atrial appendage closure using WATCHMAN FLX (WM-FLX) and WATCHMAN-2.5 (WM2.5) devices in Asian patients. METHODS AND RESULTS: Data of 1,464 consecutive patients (WM-FLX, n=909; WM2.5, n=555) were extracted from a Japanese multicenter registry, and clinical data were compared between the 2 groups. No in-hospital deaths, periprocedural stroke, or device embolization occurred. Procedural success was significantly higher in the WM-FLX than WM2.5 group (95.8% vs. 91.9%; P=0.002) owing to the lower incidence of periprocedural pericardial effusion (0.55% vs. 1.8%; P=0.021). No significant differences in all-cause death, postprocedural stroke, and device-related thrombus were observed between the 2 groups. However, the cumulative bleeding rate at 1 year was substantially lower in the WM-FLX group (7.8% vs. 16.4%; P<0.001). Landmark analysis of bleeding events highlighted lower bleeding rates in the WM-FLX than WM2.5 group within the first 6 months (6.4% vs. 14.8%; P<0.001), with comparable bleeding rates over the 6- to 12-month period (1.5% vs. 3.2%, respectively; P=0.065). CONCLUSIONS: This study demonstrated higher early safety and lower 1-year bleeding rates in the WM-FLX than WM2.5 group. The lower bleeding events with WM-FLX are likely due to multiple factors other than purely difference in devices, such as postprocedural drug regimen.

Safety of Amulet Left Atrial Appendage Occluder and Watchman Device for Left Atrial Appendage Closure in Patients With Atrial Fibrillation.

BACKGROUND: Left atrial appendage (LAA) closure is an alternative to chronic anticoagulation for stroke prevention in patients with nonvalvular atrial fibrillation. Multiple devices were used for LAA closure, with the Amplatzer Amulet LAA Occluder (Abbott, Chicago, IL, USA) and Watchman device (Boston Scientific, Marlborough, MA, USA) being the most commonly used in clinical practice. In August 2021, the FDA approved the use of the Amplatzer Amulet LAA Occluder. There is still a knowledge gap in the safety profile of the Amplatzer Amulet LAA Occluder device in comparison to the Watchman device. OBJECTIVE: The aim of this study was to assess and compare the safety profile peri-procedure and post-procedure between the Amplatzer Amulet LAA Occluder and Watchman devices. METHODS: Patients who underwent LAA closure using Watchman or Amulet devices from July 2015 to August 2020 at the American University of Beirut Medical Center were included in the analysis. Primary endpoints included peri-operative and post-procedural complications (thromboembolic events, bleeding complications, vascular access complications, pericardial effusion/tamponade, device positional complications and in-hospital death). RESULTS: The study included 37 patients (21 had Watchman devices, 16 had Amplatzer Amulet LAA Occluder devices, and 28 were men, mean age 76.57 ± 9.3 years). Seven patients developed post-procedural iatrogenic atrial septal defects (four in the Watchman group vs three in the Amulet group, p-value=0.982). Three patients developed pericardial effusion (one in the Watchman vs two in the Amulet group, p-value=0.394). Only one patient developed peri-device leak (one in the Watchman group vs none in the Amulet group, p-value=0.283). One device could not be deployed (one in the Amulet group vs none in the Watchman group, p-value=0.191). None of the patients developed in-hospital death, cardiac tamponade, device embolism, device thrombosis, stroke/transient ischemic attack (TIA), cranial bleeding, or arrhythmias after the procedure. The rate of peri-operative complications was similar between both groups. Both groups displayed low rates of adverse events in the peri-operative and post-operative periods. CONCLUSION: There was no significant difference in the safety profile of Amplatzer Amulet LAA Occluders and Watchman devices. There was a low incidence of peri-operative and post-operative adverse events with the implanted devices.

A case report of postcardioversion device-related thrombus in a patient with left atrial appendage occlusion device on apixaban.

Background: Current guidelines recommend proceeding with cardioversion, without the explicit need for preprocedural transesophageal echocardiography (TEE), in patients compliant with oral anticoagulation for at least 3 weeks. The relevance of these guidelines remains unclear in those undergoing repeat cardioversion. Case summary: A 66-year-old male with a history of atrial fibrillation (AF) and a left atrial appendage occlusion (LAAO) device, compliant with apixaban, presented with dyspnea and lightheadedness. He was cardioverted into sinus rhythm, 10 days before symptom onset, with TEE unremarkable at the time. An ECG revealed that the patient converted back into AF and a repeat cardioversion was scheduled. At the patient's request, a TEE was obtained, revealing a new 2 cm×1 cm thrombus in the left atrium above the WATCHMAN device. Cardioversion was canceled and the patient was hospitalized for AF management. Discussion: Cardioverted patients are at risk for thrombus formation due to atrial stunning, a transitory dysfunction of the atrial appendage and atrium, which occurs immediately after cardioversion and can persist for several weeks. The likelihood of a thrombus is further propagated by individual risk factors for stroke. Conclusion: Anticoagulation does not eliminate the risk of thrombus formation in those with increased risk factors for stroke. Further studies are warranted to assess the need for routine TEE, after cardioversion, in those with stroke risk factors on anticoagulation or who have LAAO.

Left atrial appendage occlusion: On the need of a numerical model to simulate the implant procedure.

Left atrial appendage occlusion (LAAO) is a percutaneous procedure to prevent thromboembolism in patients affected by atrial fibrillation. Despite its demonstrated efficacy, the LAA morphological complexity hinders the procedure, resulting in postprocedural drawbacks (device-related thrombus and peri-device leakage). Local anatomical features may cause difficulties in the device's positioning and affect the effectiveness of the device's implant. The current work proposes a detailed FE model of the LAAO useful to investigate implant scenarios and derive clinical indications. A high-fidelity model of the Watchman FLX device and simplified parametric conduits mimicking the zone of the LAA where the device is deployed were developed. Device-conduit interactions were evaluated by looking at clinical indicators such as device-wall gap, possible cause of leakage, and device protrusion. As expected, the positioning of the crimped device before the deployment was found to significantly affect the implant outcomes: clinician's choices can be improved if FE models are used to optimize the pre-operative planning. Remarkably, also the wall mechanical stiffness plays an important role. However, this parameter value is unknown for a specific LAA, a crucial point that must be correctly defined for developing an accurate FE model. Finally, numerical simulations outlined how the device's configuration on which the clinician relies to assess the implant success (i.e., the deployed configuration with the device still attached to the catheter) may differ from the actual final device's configuration, relevant for achieving a safe intervention.

Inter-atrial septal balloon dilation to facilitate intracardiac echocardiography guided left atrial appendage occlusion.

INTRODUCTION: Percutaneous left atrial appendage occlusion (LAAO) is traditionally performed under general anesthesia with trans-esophageal echocardiography guidance. Intracardiac echo (ICE)-guided LAAO closure is increasing in clinical use. The ICE catheter is crossed into LA via interatrial septum (IAS) after the septum is dilated with LAAO delivery sheath. This step can be time-consuming and requires significant ICE catheter manipulation, which increases the risk of cardiac perforation. Pre-emptive septal balloon dilation can potentially help with ICE advancement in the LA. We sought to evaluate the effect of pre-dilation of the IAS with an 8 mm balloon on the ease of crossing the ICE catheter, fluoroscopy time for crossing, and overall procedure time. METHODS: The Piedmont LAAO registry was used to identify consecutive patients who underwent LAAO. The initial 25 patients in whom balloon dilation of the IAS was performed served as the experimental cohort, and the 25 consecutive patients before that in whom balloon dilation was not performed served as controls. In the experimental group, after a trans-septal puncture, the sheath was retracted to the right atrium with a guidewire still in the LA. An 8 × 40 mm Evercoss™ over the wire balloon was inflated across the IAS. The ICE catheter was then crossed into the LA using the fluoroscopic landmark of the guide wire and the ICE imaging. The sheath was then advanced along the ICE catheter via the transseptal puncture (TSP) and the procedure continued. Follow-up compputed tomography imaging was obtained at 4-8 weeks. RESULTS: Each group consisted of 25 patients. There were no significant differences in baseline characteristics. All procedures were performed successfully under conscious sedation and ICE guidance. There was a significant reduction in the overall procedure time, fluoroscopy time, and time for transseptal puncture to ICE in LA. There was no difference in the size of the acute residual interatrial shunt, as measured via ICE, or the size and presence of iatrogenic ASD at follow-up. CONCLUSION: Balloon dilation of TSP is safe and is associated with increased efficiency in ICE-guided LAAO procedures.

Comparative Costs to Medicare and Medicare Beneficiaries of Alternative AF Stroke Risk Reduction Strategies.

Background: As healthcare costs are increasingly being shifted from payers to patients, it is important to understand the economic consequences of therapeutic strategies to both payers and patients. Objective: To determine the relative costs to Medicare and Medicare beneficiaries (patients) of warfarin, non-vitamin K oral anticoagulants (NOACs), and left atrial appendage closure (LAAC) for stroke risk reduction in nonvalvular atrial fibrillation. Methods: An economic model was developed to assess costs at 5 and 10 years. For warfarin and NOACs, inputs were derived from published meta-analyses; for LAAC with the Watchman device, inputs were derived from pooled 5-year PROTECT AF and PREVAIL trial results. The model captured therapy costs vs clinical event costs, including procedural complications and follow-up clinical outcomes. Costs were based on 2023 Medicare reimbursement and copayment rates. Results: At 10 years, overall LAAC costs ($48,337) were lower than those of NOACs ($81,198) and warfarin ($52,359). Overall LAAC costs were lower than those of NOACs by year 5 and warfarin by year 9. At 5 years, patient LAAC costs were lowest at $4,764, compared to $7,146 and $6,453 for NOACs and warfarin, respectively. LAAC patient costs were lower than those of NOACs by year 3 and warfarin by year 4. Clinical events comprised 96% of overall warfarin costs vs 48% for LAAC and 40% for NOACs. Conclusion: LAAC yielded the lowest overall and patient costs. Warfarin costs were largely driven by clinical events, which may represent an unplanned financial burden for patients. These considerations should be incorporated into shared decision-making discussions about stroke prophylaxis strategies.

ST-Segment Elevation During Percutaneous Left Atrial Appendage Closure.

A 70-year-old patient with paroxysmal atrial fibrillation underwent left atrial appendage closure. The patient experienced transient hypotension during device implantation. The procedure was abandoned because of ST-T-wave changes on electrocardiography and elevated coronary flow velocity on transesophageal echocardiography, which indicated that the device caused coronary artery compression.

Clinical outcomes of patients referred for left atrial appendage exclusion who did and did not undergo the procedure.

BACKGROUND: Left atrial appendage exclusion (LAAE) is an effective alternative to long-term anticoagulation in patients with atrial fibrillation. Not all patients considered for LAAE undergo the procedure because of ineligibility, anatomic or medical constraints, and preference of the patient. OBJECTIVE: The objective of this study was to report on the management strategies and long-term clinical outcomes of patients referred to a dedicated multidisciplinary LAAE clinic, including all who subsequently did and did not undergo LAAE. METHODS: This was a retrospective analysis of prospectively acquired data from all patients referred to the comprehensive multidisciplinary LAAE clinic at the University of Michigan between 2016 and 2022. A consecutive 301 patients (age, 75 ± 8 years; 106 women) with atrial fibrillation were evaluated. LAAE was performed in 168 patients (56%) with use of the Watchman device in 146 (49%) and surgically in 22 (7%). LAAE was not performed in 133 patients (44%, no-LAAE group) because of ineligibility in 62 (21%), anatomic constraints in 23 (7%), and preference of the patient in 48 (36%). The CHA2DS2-VASc score (4.7 ± 1.5 vs 4.1 ± 1.6; P = .002) and HAS-BLED score (3.4 ± 1.0 vs 2.8 ± 1.1; P < .001) were higher in the LAAE groups. RESULTS: Anticoagulant therapy was discontinued in 137 of 146 (94%) and 61 of 133 (61%) in the Watchman and no-LAAE groups, respectively (P < .001). During a median follow-up of 2.2 years (interquartile range, 1.2-4.0 years), in the LAAE (n = 168) and no-LAAE (n = 133) groups, respectively, 39 (23%) vs 29 (22%) deaths, 13 (8%) vs 5 (4%) thromboembolic events, and 24 (14%) vs 23 (17%) bleeding complications occurred. Continued long-term anticoagulation was not a predictor of clinical outcomes. CONCLUSION: After a comprehensive evaluation in a multidisciplinary clinic, ∼50% of the patients referred for LAAE did not proceed with LAAE and resumed anticoagulation.