Short-term antiplatelet versus anticoagulant therapy after left atrial appendage closure: a systematic review and meta-analysis.

This meta-analysis compared the efficacy and safety of different antithrombotic regimens after left atrial appendage closure (LAAC). PubMed, Embase, Medline, Cochrane Library databases were systematically searched from their inception to March 2023. Patients were divided into short-term oral anticoagulation (OAC) group and antiplatelet therapy (APT) group. The incidence of events were performed using RevMan 5.4. The events including device-related thrombus (DRT), ischemic stroke/systemic embolization (SE), major bleeding, any bleeding, any major adverse event and all-cause mortality. Subgroup analysis were based on OAC alone or OAC plus single antiplatelet therapy (SAPT) in OAC group. Oral anticoagulants include warfarin and direct oral anticoagulant (DOAC). Fourteen studies with 35,166 patients were included. We found that the incidence of DRT (OR = 0.49, 95% CI 0.36-0.66, P＜0.0001) and all-cause mortality (OR = 0.71, 95% CI 0.57-0.89, P = 0.002) were significantly lower in OAC group than APT group. However, there was no statistical differences in the incidence rates of ischemic stroke/SE (OR = 0.77, 95% CI 0.49-1.20, P = 0.25), major bleeding (OR = 0.84, 95% CI 0.55-1.27, P = 0.84), any bleeding (OR = 0.83, 95% CI 0.56-1.22, P = 0.34) and any major adverse event (OR = 0.56, 95% CI 0.30-1.03, P = 0.06) in the two groups. Subgroup analysis found that the incidence of DRT, all-cause mortality and any major adverse event in OAC monotherapy were lower than that in APT group (P＜0.05), but not statistically different from other outcome. The incidence of DRT, all-cause mortality, any major adverse event and any bleeding in DOAC were significantly better than APT group (P＜0.05). While warfarin only has better incidence of DRT than APT (P＜0.05), there was no statistical difference between the two groups in other outcome (P＞0.05). The incidence of DRT was significantly lower than APT group (P＜0.05), major bleeding were higher, and the rest of the outcome did not show any statistically significant differences(P＞0.05) when OAC plus SAPT. Based on the existing data, short-term OAC may be favored over APT for patients who undergo LAAC. DOAC monotherapy may be favored over warfarin monotherapy or OAC plus APT, when selecting anticoagulant therapies.

Impact of gender in patients with device-related thrombosis after left atrial appendage closure - A sub-analysis from the multicenter EUROC-DRT-registry.

BACKGROUND: Device-related thrombosis (DRT) is a common finding after left atrial appendage closure (LAAC) and is associated with worse outcomes. As women are underrepresented in clinical studies, further understanding of sex differences in DRT patients is warranted. METHODS AND RESULTS: This sub-analysis from the EUROC-DRT-registry compromises 176 patients with diagnosis of DRT after LAAC. Women, who accounted for 34.7% (61/176) of patients, were older (78.0 ± 6.7 vs. 74.9 ± 9.1 years, p = .06) with lower rates of comorbidities. While DRT was detected significantly later in women (173 ± 267 vs. 127 ± 192 days, p = .01), anticoagulation therapy was escalated similarly, mainly with initiation of novel oral anticoagulant (NOAC), vitamin K antagonist (VKA) or heparin. DRT resolution was achieved in 67.5% (27/40) of women and in 75.0% (54/72) of men (p = .40). In the remaining cases, an intensification/switch of anticoagulation was conducted in 50.% (9/18) of men and in 41.7% (5/12) of women. Final resolution was achieved in 72.5% (29/40) cases in women, and in 81.9% (59/72) cases in men (p = .24). Women were followed-up for a similar time as men (779 ± 520 vs. 908 ± 687 days, p = .51). Kaplan-Meier analysis revealed no difference in mortality rates in women (Hazard Ratio [HR]: 1.73, 95%-Confidence interval [95%-CI]: .68-4.37, p = .25) and no differences in stroke (HR: .83, 95%-CI: .30-2.32, p = .72) within 2 years after LAAC. CONCLUSION: Evaluation of risk factors and outcome revealed no differences between men and women, with DRT in women being diagnosed significantly later. Women should be monitored closely to assess for DRT formation/resolution. Treatment strategies appear to be equally effective.

What characterizes device-related thrombosis following LAAC, if ejection fraction fails to shine?

Cardiac compartmental size depends on sex, with smaller values found in (healthy) women compared to a matched group of men. Various types of heart disease may cause dilation of the affected chamber. For example, atrial fibrillation (AF) is associated with enlarged left atrial (LA) size, often also implying increased left ventricular (LV) size. Sex-specific differences appear to persist during disease states. Thus, chamber volumes depend on both sex and the severity of the underlying disorder, and require quantification to evaluate the effect of interventions. Often, we rely on the popular performance metric ejection fraction (EF) which refers to the ratio of the minimum and maximum LV or LA volumetric values observed during the cardiac cycle. Here we discuss a sex stratified analysis of LVEF and LAEF in AF patients as treated by LA appendage closure, while comparing those with or without device-related thrombosis. Also, an alternative analysis based on primary data is presented while emphasizing its attractiveness. In any event, age- and sex-specific reference values as broadly documented for various imaging modalities should be applied to LA and LV.

Antithrombotic Therapy after Percutaneous Left Atrial Appendage Closure: Evidence, Challenges and Future Directions.

Percutaneous left atrial appendage closure (LAAC) has been established in clinical practice as an attractive alternative to oral anticoagulation for preventing stroke in patients with atrial fibrillation and high bleeding risk. The devices approved in Europe and United States (US) for percutaneous LAAC contain metal and antithrombotic therapy is strongly recommended after their implantation to prevent apposition of thrombus on the atrial surface of the device during endothelialization. However, there is still uncertainty regarding the optimal antithrombotic drug regimen following device implantation in view of the incomplete understanding of the LAAC device healing process, the lack of randomized clinical trials comparing different antithrombotic agents after LAAC and the heterogeneous bleeding risk of patients undergoing LAAC. Thus, this review aims to evaluate the available evidence and the remaining challenges related to the post-LAAC antithrombotic regimens. Furthermore, common clinical scenarios associated with challenging management of antithrombotic therapy after LAAC and potential future directions, will be discussed.

3-Year outcomes after left atrial appendage closure in patients with nonvalvular atrial fibrillation: cardiomyopathy related with increased death and stroke rate.

INTRODUCTION: Left atrial appendage closure (LAAC) is a novel treatment for stroke prevention in high-risk patients with non-valvular atrial fibrillation (NVAF). However, the long-term outcomes after LAAC in Chinese NVAF patients are still lacking. METHODS: This was a single-center, bidirectional, nonrandomized registered study. Patients who underwent LAAC implantation from May 2014 to April 2021 in a large Chinese center were enrolled. The primary endpoint was combined all-cause death and stroke. RESULTS: From May 2014 to April 2021, a total of 673 NVAF patients were enrolled. The overall successful implantation rate was 97.62% (657 of 673). The rate of perioperative adverse events was 1.19% (8 of 673), including 3 cardiac tamponades, 2 ischemic strokes, one device-related thrombus (DRT) and 2 device dislocations. 604 (92.24%) patients completed the follow-up, the median follow-up period was 36.9 months (IQR 24.8-56.5 months). 16 stroke events occurred in 15 patients (one patient suffered from both hemorrhagic and ischemic strokes). 13 patients (2.15%) had ischemic stroke, and the fatal rate was 0.33% (2 of 604). 3 patients (0.15%) suffered from hemorrhagic stroke, and the fatal rate was 0.17% (1 of 604). The overall stroke rate was 0.74% per-year. The combined death and stroke rate was 1.93% per-year. In the multivariate Cox regression analysis, age ≥ 75 (hazard ratio 2.264, 95% CI 1.074-4.772, P = 0.032) and ventricular cardiomyopathy (hazard ratio 2.738, 95% CI 1.060-7.071, P = 0.037) were independent predictors of combined mortality and stroke. CONCLUSION: The overall successful implantation rate of LAAC was 97.62% and the rate of perioperative adverse events was 1.19% in this study, and the stroke rate was 0.74% per year during the long-term follow-up. Age ≥ 75 years and ventricular cardiomyopathy were independent predictors of the primary endpoint. Trial registration This study was retrospectively registered.

Watchman FLX vs. Watchman 2.5 in a Dual-Center Left Atrial Appendage Closure Cohort: the WATCH-DUAL study.

AIMS: No studies have compared Watchman 2.5 (W2.5) with Watchman FLX (FLX) devices to date. We aimed at comparing the FLX with W2.5 devices with respect to clinical outcomes, left atrial appendage (LAA) sealing properties and device-related thrombus (DRT). METHODS AND RESULTS: All consecutive left atrial appendage closure (LAAC) procedures performed at two European centres between November 2017 and February 2021 were included. Procedure-related complications and net adverse cardiovascular events (NACE) at 6 months after LAAC were recorded. At 45-day computed tomography (CT) follow-up, intra- (IDL) and peri- (PDL) device leak, residual patent neck area (RPNA), and DRT were assessed by a Corelab. Out of 144 LAAC consecutive procedures, 71 and 73 interventions were performed using W2.5 and FLX devices, respectively. There were no differences in terms of procedure-related complications (4.2% vs. 2.7%, P = 0.626). At 45-day CT, the FLX was associated with lower frequency of IDL [21.3% vs. 40.0%; P = 0.032; odds ratio (OR): 0.375; 95% confidence interval (CI): 0.160-0.876; P = 0.024], similar rate of PDL (29.5% vs. 42.0%; P = 0.170), and smaller RPNA [6 (0-36) vs. 40 (6-115) mm2; P = 0.001; OR: 0.240; 95% CI: 0.100-0.577; P = 0.001] compared with the W2.5 group. At 45 days, rate of DRT as detected by CT and/or transoesophageal echocardiography (TOE), was higher with W2.5 (6.0% vs. 0%, P = 0.045). At 6-month follow-up, NACE did not differ between groups. CONCLUSIONS: In this cohort of consecutive LAACs, FLX as compared to W2.5, was associated with similar procedure-related complications and 6-month NACE, but with improved LAA neck coverage, and lower IDL and DRT.

Unexpected large device related thrombus at 12 months follow-up after left atrial appendage closure.

An 89-year-old woman underwent left atrial appendage (LAA) closure (LAAC) in our hospital because of recurrent gastrointestinal bleedings. The first transesophageal echocardiography (TEE) follow-up at six weeks revealed a complete sealing of the LAA and no device related thrombus. In a TEE follow-up at one year after the LAA closure, a large device related thrombus (6 × 3 cm) was found. Treated with oral anticoagulation (apixaban) the thrombus showed a partial resolution one year later.

Utility of transesophageal echocardiogram surveillance after watchman device placement.

BACKGROUND: In atrial fibrillation patients undergoing left atrial appendage occlusion with a Watchman device, surveillance imaging with a transesophageal echocardiogram (TEE) is typically performed at 45 days and 1 year to evaluate for device-related thrombus (DRT) and peri-device leak (PDL) before the cessation of oral anticoagulation. The incidence of these complications is relatively low, and the ideal timing and duration of surveillance is unknown. We sought to evaluate the incidence of DRT and PDL after Watchman placement at 45 days and 1 year to determine the necessity of surveillance TEEs. METHODS: We retrospectively analyzed 361 patients who received a Watchman device between January 2016 and January 2020. Baseline clinical and echocardiographic data, post-procedure antithrombotic therapy, and surveillance echocardiographic data were collected from the NCDR LAAO Registry. Nested backward variable elimination regression was performed to derive independent predictors of the composite outcome of DRT and PDL. RESULTS: A total of 286 patients who had post-procedure TEEs were included in the analysis. At 45 days, 9 patients had DRT (3.2%) and 44 patients had PDL (15.0%). At 1 year, 5 patients had DRT (5.6%) and 8 patients had PDL (8.9%). All DRT at 45 days was treated with continued anticoagulation while no change in protocol occurred with PDL. All DRT at 1 year occurred in new patients without prior thrombus. A history of prior transient ischemic attack (TIA) and thromboembolism was significantly associated with DRT or PDL at 1 year. CONCLUSIONS: We identified several patients with device-related complications at 45 days and 1 year despite appropriate device sizing and adequate use of antithrombotic therapy. The incidence of DRT increased from 45 days to 1 year and occurred in patients without prior thrombus. These findings highlight the importance of surveillance imaging and suggest the potential need for extended surveillance in select patients.

Incidence, predictors and outcomes of device-related thrombus after left atrial appendage closure with the WATCHMAN device-Insights from the EWOLUTION real world registry.

BACKGROUND: In this analysis of the EWOLUTION registry, we evaluated the incidence, relevance and predictors of device-related thrombus in a large multi-center real-world cohort undergoing LAAc with the WATCHMAN device. METHODS AND RESULTS: We analyzed the 835 patients who underwent percutaneous LAA closure with the WATCHMAN device in the EWOLUTION registry in whom at least one TEE follow up was performed. Patients were 74 ± 9 y/o and were at high risk for stroke and bleeding (CHA2DS2-VASC-Score 4.3 ± 1.7; HAS-BLED-Score 2.3 ± 1.2). Device-related thrombus was detected in 4.1% (34/835) after a median of 54 days (IQR 42-111 days) with 91.2% (31/34) being detected within 3 months after the procedure or at the time of first TEE. Hereby DRT occurred irrespective of postprocedural anticoagulation. Patients with DRT more frequently had long-standing, non-paroxysmal atrial fibrillation (82.4 vs. 64.9%, p < .01), evidence of dense spontaneous echo contrast (26.5 vs. 11.9%, p = .03) and larger LAA diameters at the ostium (22.8 ± 3.5 vs. 21.1 ± 3.5 mm, p < .01) compared to patients without DRT. Left ventricular ejection fraction, device compression ratio and the incidence of renal dysfunction did not differ between the two groups. In a multivariate analysis, only non-paroxysmal atrial fibrillation identified as an independent predictor of developing DRT. Specific treatment of DRT was initiated in 62% (21/34) of patients whereas resolution was confirmed in 86% (18/21) of cases. Overall, no significant differences in annual rates of stroke/TIA or systemic embolism were observed in patients with or without DRT (DRT 1.7 vs. No-DRT 2.2%/year, p = .8). CONCLUSIONS: In real-world patients undergoing LAAc with the WATCHMAN device, DRT is rare. DRT was most frequently detected within the first 3 months after LAAc regardless of post-procedural regimen and was not associated with an increased risk of stroke or SE. While long-standing atrial fibrillation was the only independent factor associated with DRT, medical treatment of DRT resulted in a resolution of thrombi in most cases.

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.

Device-Related Thrombus After Left Atrial Appendage Occlusion With the Amulet Device.

BACKGROUND: Left atrial appendage occlusion (LAAO) is increasingly used for stroke prevention in patients with atrial fibrillation who are considered unsuitable for a lifelong oral anticoagulant regimen. Recently, a single-centre study reported device-related thrombus formation in 16.7% of patients treated with the second-generation Amulet device (St. Jude Medical, St. Paul, MN, USA), presenting a potential major safety concern. As "real-world" data on device-related thrombus formation following LAAO with the Amulet occluder are scarce, we aimed to evaluate this outcome in a retrospective registry. METHODS: Clinical and tranosesophageal echocardiography data after LAAO with the Amulet in consecutive patients from three centres were collated. RESULTS: Among 38 patients (mean age 75.8 years), mean (standard deviation) CHA2DS2-VASc and HAS-BLED scores were 4.4 (1.2) and 3.4 (0.9), respectively. All patients underwent successful device placement without procedure-related adverse events. The antithrombotic regimen at discharge consisted of dual antiplatelet therapy (DAPT) in 27 patients (71.1%), single antiplatelet therapy in 10 patients (26.3%), and no antithrombotic therapy in one patient (2.6%). Device-related thrombus was observed in one patient (2.6%) despite DAPT regimen. The outcome of this patient was uncomplicated after adjustment of oral anticoagulant therapy. No patients presented with a thromboembolic event following LAAO during a mean (standard deviation) follow-up of 15 (5) months. CONCLUSIONS: In this retrospective study, device-related thrombus formation with the second-generation Amulet device was rare and occurred at a rate similar to that of the previous device. Importantly, no patient experienced a device-related thromboembolic event during follow-up. Larger real-life studies are required to confirm the safety profile of this increasingly used device.

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.

Antithrombotic Therapy in Patients Undergoing Percutaneous Left Atrial Appendage Occlusion.

Percutaneous left atrial appendage closure (LAAC) is a valid alternative to oral anticoagulation to prevent ischemic stroke in patients with atrial fibrillation.The devices approved in Europe and United States for percutaneous LAAC contain metal and temporary antithrombotic therapy is strongly recommended following implantation to prevent thrombus formation on the atrial device surface. There is still uncertainty regarding to the optimal antithrombotic drug regimen after device implantation for several reasons. Thus, this review aims at summarizing the available evidence and the remaining challenges related to the management of antithrombotic therapy in the context of LAAC procedure.

Percutaneous left atrial appendage closure with the Watchman device: a systematic review.

Atrial fibrillation (AF) is the most commonly observed arrhythmia in the world and its prevalence increases with age. The main and most severe complication of AF is ischemic stroke. Oral anticoagulation (OAC) therapy is the standard of care for stroke prevention in the high risk population. Initiation of this treatment is associated with a substantial risk of bleeding complications. Moreover, there is a group of patients who cannot tolerate OAC. In patients with AF the left atrial appendage (LAA) is the main source of thrombus formation. Percutaneous left atrial appendage closure (LAAC) has become an important non-pharmacological intervention for stroke prevention in patients with non-valvular AF. The procedure aims to reduce the risk of thromboembolism without increasing the risk of bleeding. Over the last few years, the safety and long-term efficacy of the procedure in specific populations have increased and more patients are being treated. The Watchman device is the most studied device in this field. Randomized controlled trials demonstrated non-inferiority of percutaneous left atrial appendage closure using the WATCHMAN 2.5 device to OAC (Boston Scientific, Marlborough, MA, USA). The new generation device, WATCHMAN FLX, was introduced and its use was associated with fewer safety events and a higher success rate of effective appendage closure. Nevertheless, several unsolved problems remain, including device-related thrombosis, the post-LAAC antithrombotic regimen, and peri-device leakage. This review will focus on LAAC with the Watchman device for stroke prevention in AF patients. Current status, available literature, clinical safety and efficacy will be summarized.

Late-onset left atrial appendage occlusion device-related thrombus attributed to mitral bioprosthetic stenosis: a case report.

Background: Left atrial appendage occlusion (LAAO) is an alternative to anticoagulation for stroke prevention in select patients with atrial fibrillation (AF). In this study, we describe the case of a patient with delayed device-related thrombus (DRT) at 13 months post-LAAO in a setting of atrial stasis due to a worsening mitral bioprosthetic stenosis. Case summary: A 69-year-old woman with a history of rheumatic mitral stenosis and regurgitation post-bioprosthetic mitral valve replacement (6 years prior) and paroxysmal AF was referred for percutaneous LAAO due to recurrent severe gastrointestinal bleeding while on anticoagulation. She underwent an uncomplicated LAAO, for which a 35 mm Watchman Flx device was used. Peri-procedural transoesophageal echocardiogram (TEE) at the time of implant showed thickened and calcified mitral bioprosthetic leaflets and a mild mitral stenosis. Her 45-day post-LAAO TEE showed a mild mitral stenosis and no peri-device leak or DRT. At 12 months, the patient had worsening exertional dyspnoea and pedal oedema. Her 12-month transthoracic echocardiogram (TTE) showed a moderate mitral stenosis and LAAO remained free of DRT. Her symptoms were deemed secondary from a worsening mitral valve stenosis. Mitral valve-in-valve (MViV) replacement was planned because the patient was deemed a prohibitive risk for a redo surgical replacement. Transthoracic echocardiogram on the day of MViV showed a large thrombus on the LAAO device. MViV was postponed. After the patient completed 45 days of anticoagulation with warfarin, a repeat TTE was performed, which showed a resolution of DRT. Transcatheter MViV was performed successfully. Discussion: This case demonstrates that increased stasis and left atrial dysfunction from prosthetic mitral stenosis can be a risk factor for late DRT after successful LAAO. The use of a LAAO occlusion device in the presence of a mitral bioprosthesis requires more frequent echocardiographic monitoring to assess both the function of the prosthesis and a delayed formation of thrombus. More studies need to be conducted to assess the safety of percutaneous LAAO devices in those with mitral bioprosthesis.

Left main coronary artery disease treated with beating heart surgery: 10-year single center results.

Introduction: Left main (LM) coronary disease is believed to represent a complex, advanced, and potentially life-threatening atherosclerotic syndrome that can be treated by either percutaneous or surgical interventions. Despite its satisfactory results, the declined number of off-pump coronary artery bypass grafting (OPCAB) is observed. Aim: To compare 10-year survival and point out possible mortality risk factors in patients referred for left main and multivessel OPCAB surgery followed by transit time bypass measurements. Material and methods: There were 159 patients (128 (81%) men and 31 (19%) women) in a median age of 66 (60-70) years enrolled in retrospective analysis who were referred to surgical intervention due to left main (51, 32%) and multivessel (108, 68%) disease. The regression analysis for long-term mortality risk and the Kaplan-Meyer survival curve were analyzed. Results: Multivariable analysis pointed female sex (HR = 1.08, 95% CI: 1.03-1.14, p = 0.001) and diabetes mellitus (HR = 6.33, 95% CI: 1.86-21.52, p = 0.003) as possible risk factors for 10-year mortality risk. There was no significant difference in Kaplan-Meyer 10-year mortality comparison between left main and multivessel disease patients treated by off-pump surgical revascularization (HR = 0.93, 95% CI: 0.40-2.13, p = 0.86). Conclusions: Off-pump surgery in the left main disease, compared to multivessel disease, represents a safe surgical technique with satisfactory long-term results. The female sex and diabetes mellitus were found as possible risk factors for 10-year mortality risk in multivariable analysis.

Incidence and predictors of device-related thrombus after left atrial appendage closure with Watchman device.

Introduction: Left atrial appendage closure (LAAC) with Watchman device prevents thromboembolism in patients with atrial fibrillation (AF). However, thrombus may develop on the atrial surface of the device. Aim: To investigate the incidence and predictors of device-related thrombus (DRT) in patients with AF who were treated with LAAC. Material and methods: Ninety-one consecutive patients with AF underwent LAAC procedure using first-generation Watchman 2.5 device followed by antiplatelet therapy. In our analysis we have included all patients (n = 78) who had clinical follow-up visits with transesophageal echocardiography (TEE) after the procedure. Results: The median (IQR) CHA2DS2-VASc score was 4 (4.0-6.0) and HAS-BLED score was 3 (3.0-4.0). DRTs were observed in 5 (6.4%) patients. When compared with patients without DRT, those with DRT presented more often with lower median ejection fraction (40% (23.5-45.5) versus 55% (48.0-60.0); p = 0.005), lower emptying velocity of LAA (25 cm/s (17.5-27.0) versus 53 cm/s (26.5-78.0); p = 0.009), and with greater depth of implantation (18 mm (14.0-20.5) versus 8 mm (5.0-11.0); p < 0.001). Furthermore, patients with DRT had greater depth of LAA (35 mm (29.5-41.0) versus 29 mm (25.5-31.0); p = 0.003), greater mean (SD) dimension in 900 (22.4 mm (3.2) versus 19 mm (2.7); p = 0.02). Patients with DRT were also younger than those without DRT (67.4 years (7) versus 75 years (8.3), p = 0.045). Conclusions: The DRT after Watchman device implantation remains a rare complication. Its formation was related to several patient and procedural characteristics, which need to be confirmed in larger studies.

Challenges and advances in device-related thrombus in left atrial appendage occlusion.

Oral anticoagulation therapy (OAC) is a mainstay for mitigating stroke and other embolic events in patients with atrial fibrillation (AF). Despite the demonstrated efficacy of OAC in reducing events, many patients are unable to tolerate OAC due to bleeding risks. Left atrial appendage occlusion (LAAO) devices were developed as implantable technologies to moderate stroke risk in patients with intolerance to OAC. Despite clinical data supporting near-comparable protection against thromboembolic events with OAC, device-related thrombus formation has emerged as a critical complication following LAAO that remains a potential limitation to the safety and efficacy of LAAO. Improved biocompatibility of LAAO devices with fluoropolymers, a well-established stent-coating technology used to reduce thrombus formation and promote endothelialization, may optimize outcomes after LAAO.

[Box: see text].

Management of complications associated with percutaneous left atrial appendage closure with or without ablation: experience from 512 cases over a 4-year period.

Background: Percutaneous left atrial appendage closure (LAAC) serves as an alternative prophylactic strategy for patients with non-valvular atrial fibrillation (AF) who cannot undergo anti-coagulation therapy. Proper management of associated complications is crucial to enhancing the procedure's success rate and mitigating perioperative risks and adverse events during follow-up. Aims: This study aims to summarize our center's experience and strategies in managing procedural-related complications encountered in 512 cases of LAAC with or without ablation for AF conducted from January 2020 to December 2023. Results: We identified 11 significant intervention-requiring complications associated with LAAC with or without Ablation procedure. These included three cases of intraoperative thrombosis, three instances of pericardial effusion or tamponade, one case of device-related thrombosis, one peri-device leak, one systemic embolism, one bleeding episode, and one additional device-related complication. The categorization of intraoperative thrombosis was as follows: one patient exhibited heparin resistance; one experienced thrombosis due to prolonged device implantation during the LAAC with ablation procedure; and one had unexplained intraoperative thrombosis. The pericardial effusion or tamponade likely resulted from damage to the atrial appendage during LAAC device insertion. Two patients encountered device-related thrombosis and systemic embolism events possibly caused by non-standard postoperative antithrombotic medication use; one patient's peri-device leak may have resulted from incomplete endothelialization of the occluder post-surgery; one patient experienced postoperative bladder bleeding; and one patient's device-related complications occurred due to a dislodged strut frame that damaged the left atrial appendage, leading to pericardial effusion. Our proactive interventions enabled all patients with these surgical-related complications to be safely discharged, with subsequent follow-ups showing no adverse events. Conclusion: Implementing targeted interventions for immediate procedural-related complications during the LAAC with or without ablation procedures enhances procedural success rates, diminishes postoperative mortality and patient disability, and bolsters stroke prevention efforts. This approach underscores the importance of a strategic response to complications, affirming the procedure's viability and safety in managing non-valvular AF in patients contraindicated for anticoagulation.

UV-Triggered Hydrogel Coating of the Double Network Polyelectrolytes for Enhanced Endothelialization.

The left atrial appendage (LAA) occluder is an important medical device for closing the LAA and preventing stroke. The device-related thrombus (DRT) prevents the implantation of the occluder in exerting the desired therapeutic effect, which is primarily caused by the delayed endothelialization of the occluder. Functional coatings are an effective strategy for accelerating the endothelialization of occluders. However, the occluder surface area is particularly large and structurally complex, and the device is subjected to a large shear friction in the sheath during implantation, which poses a significant challenge to the coating. Herein, a hydrogel coating by the in situ UV-triggered polymerization of double-network polyelectrolytes is reported. The findings reveal that the double network and electrostatic interactions between the networks resulted in excellent mechanical properties of the hydrogel coating. The sulfonate and Arg-Gly-Asp (RGD) groups in the coating promoted hemocompatibility and endothelial growth of the occluder, respectively. The coating significantly accelerated the endothelialization of the LAA occluder in a canine model is further demonstrated. This study has potential clinical benefits in reducing both the incidence of DRT and the postoperative anticoagulant course for LAA closure.