Left Atrial Appendage Occlusion Research Articles

Left Atrial Appendage Occlusion and Post-procedural Antithrombotic Management

Left atrial appendage occlusion (LAAO) is an established alternative to oral anticoagulation for stroke prevention in atrial fibrillation. Antithrombotic therapy is used in the post-procedural period to prevent device-related thrombosis (DRT). The risk of DRT is considered highest in the first 45–90 days after device implantation, based on animal studies of the device healing process. Clinically applied antithrombotic regimens vary greatly across studies, continents, and centers. This article gives an overview of the evidence behind current antithrombotic regimens, ongoing randomized trials, and future post-procedural management.

Minimally invasive epicardial surgical left atrial appendage exclusion for atrial fibrillation patients at high risk for stroke and for bleeding

BackgroundAtrial fibrillation (AF) patients at high risk for stroke and for bleeding may be unsuitable for either oral anticoagulation or endocardial left atrial appendage (LAA) occlusion. However, minimally invasive, epicardial left atrial appendage exclusion (LAAE) may be an option. ObjectiveThe purpose of this study was to evaluate outcomes of LAAE in high-risk AF patients not receiving oral anticoagulation. MethodsA retrospective analysis of Medicare claims data was conducted to evaluate thromboembolic events in AF patients who underwent LAAE compared to a 1:4 propensity score–matched group of patients who did not receive LAAE (control). Neither group was receiving any oral anticoagulation at baseline or follow-up. Fine-Gray models estimated hazard ratios and evaluated between-group differences. Bootstrapping was applied to generate 95% confidence intervals (CIs). ResultsThe LAAE group (n = 243) was 61% male (mean age 75 years). AF was nonparoxysmal in 70% (mean CHA2DS2-VASc score 5.4; mean HAS-BLED score 4.2). The matched control group (n = 972) had statistically similar characteristics. One-year adjusted estimates of thromboembolic events were 7.3% (95% CI 4.3%–11.1%) in the LAAE group and 12.1% (95% CI 9.5%–14.8%) in the control group. Absolute risk reduction was 4.8% (95% CI 0.6%–8.9%; P = .028). Adjusted hazard ratio for thromboembolic events for LAAE vs non-LAAE was 0.672 (95% CI 0.394–1.146). ConclusionIn AF patients not taking oral anticoagulation who are at high risk for stroke and for bleeding, minimally invasive, thoracoscopic, epicardial LAAE was associated with a lower rate of thromboembolic events.

Multi-network approach for image segmentation in non-contrast enhanced cardiac 3D MRI of arrhythmic patients

Left atrial appendage (LAA) is the source of thrombi formation in more than 90% of strokes in patients with nonvalvular atrial fibrillation. Catheter-based LAA occlusion is being increasingly applied as a treatment strategy to prevent stroke. Anatomical complexity of LAA makes percutaneous occlusion commonly performed under transesophageal echocardiography (TEE) and X-ray (XR) guidance especially challenging. Image fusion techniques integrating 3D anatomical models derived from pre-procedural imaging into the live XR fluoroscopy can be applied to guide each step of the LAA closure. Cardiac magnetic resonance (CMR) imaging gains in importance for radiation-free evaluation of cardiac morphology as alternative to gold-standard TEE or computed tomography angiography (CTA). Manual delineation of cardiac structures from non-contrast enhanced CMR is, however, labor-intensive, tedious, and challenging due to the rather low contrast. Additionally, arrhythmia often impairs the image quality in ECG synchronized acquisitions causing blurring and motion artifacts. Thus, for cardiac segmentation in arrhythmic patients, there is a strong need for an automated image segmentation method. Deep learning-based methods have shown great promise in medical image analysis achieving superior performance in various imaging modalities and different clinical applications. Fully-convolutional neural networks (CNNs), especially U-Net, have become the method of choice for cardiac segmentation. In this paper, we propose an approach for automatic segmentation of cardiac structures from non-contrast enhanced CMR images of arrhythmic patients based on CNNs implemented in a multi-stage pipeline. Two-stage implementation allows subdividing the task into localization of the relevant cardiac structures and segmentation of these structures from the cropped sub-regions obtained from previous step leading to efficient and effective way of automated cardiac segmentation.

Left atrial appendage occlusion vs oral anticoagulants in AF and coronary stenting. The DESAFIO registry

Left atrial appendage occlusion vs oral anticoagulants in AF and coronary stenting. The DESAFIO registry

Lower rate of major bleeding in very high risk patients undergoing left atrial appendage occlusion: A propensity score–matched comparison with direct oral anticoagulant

BackgroundLong-term oral anticoagulation is the mainstay therapy for thromboembolic (TE) prevention in patients with atrial fibrillation. However, left atrial appendage occlusion (LAAO) could be a safe alternative to direct oral anticoagulants (DOACs) in patients with a very high TE risk profile. ObjectiveThe purpose of this study was to compare the safety and efficacy of LAAO vs DOACs in patients with atrial fibrillation at very high stroke risk (CHA2DS2-VASc [congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism, vascular disease, age 65–74 years, sex category] score ≥ 5). MethodsData from patients with CHA2DS2-VASc score ≥ 5 were extracted from a prospective multicenter database. To attenuate the imbalance in covariates between groups, propensity score matching was used (covariates: CHA2DS2-VASc and HAS-BLED [hypertension, abnormal renal or liver function, stroke, bleeding, labile international normalized ratio, elderly, drugs or alcohol] scores), which resulted in a matched population of 277 patients per group. The primary end point was a composite of cardiovascular death, TE events, and clinically relevant bleeding during follow-up. ResultsOf 2381 patients, 554 very high risk patients were included in the study (mean age 79 ± 7 years; CHA2DS2-VASc score 5.8 ± 0.9; HAS-BLED score 3.0 ± 0.9). The mean follow-up duration was 25 ± 11 months. A higher incidence of the composite end point was documented with DOACs compared with LAAO (14.9 events per 100 patient-years in the DOAC group vs 9.4 events per 100 patient-years in the LAAO group; P = .03). The annualized clinically relevant bleeding risk was higher with DOACs (6.3% vs 3.2%; P = .04), while the risk of TE events was not different between groups (4.1% vs 3.2%; P = .63). ConclusionIn high-risk patients, LAAO had a similar stroke prevention efficacy but a significantly lower risk of clinically relevant bleeding when compared with DOACs. The clinical benefit of LAAO became significant after 18 months of follow-up.

The ventilation efficacy and safety of new nasopharyngeal airway applied in left atrial appendage occlusion

Objective: The present retrospective study aimed to analyses the ventilation efficacy and safety of new nasopharyngeal airway applied in left atrial appendage occlusion. Methods: A total of 37 advanced aged patients diagnosed with atrial fibrillation(>65 years)who underwent left atrial appendage occlusion (LAAO) in Xuanwu Hospital of Capital Medical University from March 2021 to March 2022 were enrolled in this study. All patients received supplemental oxygen by a new nasopharyngeal airway to ensure intraoperative ventilation. The primary outcome was the occurrence of hypoxemia. The secondary outcomes included the incidence of hypotension after anesthesia, the incidence of body movement during surgery, significant fluctuations of the vital signs such as mean arterial pressure (MAP), heart rate (HR), saturation of pulse oxygen (SpO2) and respiratory rate (RR) at different time points (T1: pre-operation; T2: at the time of placing nasopharyngeal airway; T3: at the time of placing transesophageal echocardiography(TEE); T4: at the time of TEE intraoperative exploration; T5: end of the surgery; T6: at the time of patient woke up), and the incidence of postoperative adverse events. Results: There were 24 males and 13 females with a mean age of (73.8±7.7) years. The incidence of hypoxemia was 16.2% (6/37), which could return to normal after simple treatment. The incidence of hypotension was 27.0% (10/37), occurred after anesthesia induction mainly.32.4% (12/37) of the patients experienced movements, but no adverse events led to surgical termination. MAP at different time points was significantly different (P=0.001), but other vital signs of HR, SpO2 and RR were not significantly different(all P>0.05), without serious hemodynamic fluctuations. The incidence of postoperative adverse cardiovascular events was 10.8% (4/37), and delirium was 2.7% (1/37). All patients successfully completed the surgery and were safely discharged from the hospital. Conclusion: The new nasopharyngeal airway can meet the requirements of airway management during left atrial appendage occlusion under intravenous anesthesia without serious adverse events.

Percutaneous left atrial appendage occlusion in mitral valve disease: A Nationwide Readmission Database analysis

BackgroundPercutaneous left atrial appendage occlusion (LAAO) has emerged as a non-pharmacologic alternative to oral anticoagulation in reducing stroke risk in AF patients. However, patients with mitral valve disease (MVD), who are expected to have a significantly greater risk of left atrium (LA) thrombus formation and embolic stroke were excluded from randomized trials examining percutaneous LAAO. To address this gap, we present a national registry analysis of the use of LAAO among patients with MVD. MethodsUsing the National Readmissions Database, we performed a retrospective review of all hospitalizations for LAAO identified between September 2015 and November 2019. Of these, patients with ICD-10 codes for MVD were identified. Propensity matched (PSM) analysis was used to compare patients with MVD with a matched sample of patients undergoing LAAO with non-valvular AF. Outcomes examined included all-cause mortality, stroke, major bleeding, pericardial effusion (PE), and tamponade. Results51,540 patients who underwent LAAO without a history of MVD and 3777 with a history of MVD were identified. Crude analysis demonstrated the odds of mortality, PE, and cardiac tamponade during index hospitalization to be higher in the MVD group. The length of stay and cost of index hospitalization were also slightly greater for the MVD group. A sample of 7649 patients (MVD: 3777 MVD and no MVD: 3872) were selected for PSM analysis with similar comorbidities across the two groups. In the PSM comparison, MVD was associated with higher risk of PE. The MVD group had a slightly higher rate of readmissions the association with PE remained at 30-day readmission (OR: 2.099 [1.360–3.238], p-value: <0.001). ConclusionTo our knowledge, this is the first study examining the use of LAAO among MVD patients. Our findings suggest that patients with MVD who underwent LAAO had a higher risk of post-procedural PE without an increase in mortality, stroke, or major bleeding. These results provide a rationale for considering LAAO as part of the stroke prevention strategy among patients with valvular AF.

Surgical ablation, left atrial appendage occlusion or both? Nationwide registry analysis of cardiac surgery patients with underlying atrial fibrillation.

The aim of this study was to evaluate in-hospital outcomes and long-term survival of patients undergoing cardiac surgery with preoperative atrial fibrillation (AF). We compared different strategies, including no-AF treatment, left atrial appendage occlusion (LAAO) alone, concomitant surgical ablation (SA) alone or both. A retrospective analysis using the KROK registry included all patients with preoperative diagnosis of AF who underwent cardiac surgery in Poland between between January 2012 and December 2022. Risk adjustment was performed using regression analysis with inverse probability weighting of propensity scores. We assessed 6-year survival with Cox proportional hazards models. Sensitivity analysis was performed based on index cardiac procedure. Initially, 42510 patients with preoperative AF were identified, and, after exclusion, 33949 included in the final analysis. A total of 1107 (3.26%) received both SA and LAAO, 1484 (4.37%) received LAAO alone, 3921 (11.55%) SA alone and the remaining 27437 (80.82%) had no AF-directed treatment. As compared to no treatment, all strategies were associated with survival benefit over 6-year follow-up. A gradient of treatment was observed with the highest benefit associated with SA + LAAO followed by SA alone and LAAO alone (log-rank P < 0.001). Mortality benefits were reflected when stratified by surgery type with the exception of aortic valve surgery where LAAO alone fare worse than no treatment. Among patients with preoperative AF undergoing cardiac surgery, surgical management of AF, particularly SA + LAAO, was associated with lower 6-year mortality. These findings support the benefits of incorporating SA and LAAO in the management of AF during cardiac surgery.

Endovascular occlusion of the left atrial appendage in atrial fibrillation: modern concepts and prospects (review)

Despite the increasingly widespread use of endovascular left atrial appendage occlusion (ELAAO) in the treatment of patients with atrial fibrillation (AF), the choice of optimal tactics for performing the procedure, especially subsequent antithrombotic therapy, remains poorly understood. This review was conducted with the aim of critically assessing current ideas about the safety and effectiveness of ELAAO in AF. The results of the most important clinical studies of ELAAO in patients with AF, the provisions of current clinical recommendations for this procedure are discussed. The available data on the possibilities of antithrombotic therapy after ELAAO and the prospects for future research in filling gaps in the evidence base for this technique are reviewed.

Real-World Management Strategies of Anticoagulated Atrial Fibrillation Patients After a Clinically Significant Bleeding Episode

BackgroundSystemic anticoagulation for stroke prevention in patients with atrial fibrillation (AF) carries inherent bleeding risks, and determining whether and when to resume anticoagulation after significant bleeding is a common dilemma. We aimed to describe the clinical characteristics of AF patients discharged after a bleeding event, document real-life thromboembolic prevention strategy (TPS), and analyse their associated clinical outcomes. MethodsWe retrospectively reviewed the charts of anticoagulated AF patients admitted for bleeding from 2017 to 2019. ResultsA total of 140 patients were included, with a mean age of 78.6 years. Four discharge groups were defined: 75 patients (53.5%) had optimal anticoagulation (OA), 37 (26.4%) had a suboptimal antithrombotic regimen (SAR; low-dose direct oral anticoagulants without dose-reduction criteria or antiplatelet therapy), 10 (7.1%) were referred for left atrial appendage occlusion (LAAO), and 18 (12.9%) left without any TPS. All-cause mortality at 2 years was high (28.6%) but not statistically different between groups (P = 0.71). Patients discharged with a TPS (OA/SAR/LAAO referral) were more likely to be readmitted for bleeding at 2 years (34% vs 0%; P = 0.002), and those discharged without a TPS had higher rates of stroke (16.6% vs 1.4%; P = 0.003). SAR yielded readmission rates for bleeding similar to resumption of OA (27% vs 34.7%; P = 0.41) but was associated with high rates of death or readmission at 2 years. ConclusionsThis real-life cohort reveals that clinicians frequently downgrade or discontinue long-term thromboembolic protection after a bleeding event despite current guideline recommendations to the contrary, and downgrading resulted in bleeding risk similar to OA.

Left atrial appendage occlusion in patients suffering from advanced chronic kidney disease (stage 4 and 5). Long-term follow-up.

Advanced chronic kidney disease (A-CKD) combined with atrial fibrillation increases the risk of both thrombogenic and bleeding events. Left atrial appendage occlusion (LAAO) may be an alternative to oral anticoagulation to prevent thromboembolic events. We aimed to evaluate the outcomes of LAAO in patients with A-CKD. Comparison at long-term follow-up of patients diagnosed with and without A-CKD (eGFR<30 mL/min/1.73 m2 ) who underwent LAAO between 2009 and May 2022. Five hundred seventy-three patients were included. Eighty-one (14%) were diagnosed with A-CKD. There were no differences in sex, age, and cardiovascular risk factors, except for diabetes which was more frequent in patients with A-CKD. The control group had higher rates of stroke, both ischemic and hemorrhagic. There were no differences in the CHA2 DS2 -VASc score, although A-CKD patients had a higher bleeding risk according to the HASBLED scale. Global procedural success was 99.1%. At follow-up, there were no differences in stroke rate: at 1-year (HR: 1.22, IC-95%: 0.14-10.42, p = 0.861); at 5-years (HR: 0.60, IC-95%: 0.08-4.58, p = 0.594). Although bleeding events were higher in the A-CKD group, no differences were found in major bleeding (defined BARC ≥ 3) at 1-year (HR: 1.34, IC-95%: 0.63-2.88, p = 0.464) or at 5-years follow-up (HR: 1.30, IC-95%: 0.69-2.48, p = 0.434). Mortality rate at 5 years was higher in the A-CKD patients (HR: 1.84, IC-95%: 1.18-2.87, p = 0.012). LAAO is an effective and safe treatment in A-CKD patients to prevent ischemic events and bleeding. This strategy could be an alternative to oral anticoagulation in this high-risk group of patients.

Outcomes Associated With Left Atrial Appendage Occlusion Via Implanted Device in Atrial Fibrillation

ObjectiveTo compare outcomes after left atrial appendage occlusion (LAAO) via implanted device vs no LAAO in a matched cohort of patients with atrial fibrillation (AF). MethodsThis longitudinal retrospective cohort study was based on the national database covering hospital care for the entire French population. Adults (≥18 years of age) who had been hospitalized with AF (January 1, 2015, to January 1, 2020) who underwent LAAO were identified. Propensity score matching was used to control for potential confounders of the treatment-outcome relationship. The primary outcome was a composite of ischemic stroke, major bleeding, or all-cause death during follow-up. ResultsAfter propensity score matching, 1216 patients with AF who were treated with LAAO were matched with 1216 controls (patients AF who were not treated with LAAO). Mean follow-up was 14.5 months (median, 13 months; IQR, 7-21 months). Patients with LAAO had a lower risk of the composite outcome (HR, 0.48; 95% CI, 0.42 to 0.55). Total events (309 for LAAO vs 640 for controls) and event rates (23.3% vs 44.0%/year, respectively) were lower for LAAO, driven primarily by a decreased risk of all-cause death (HR, 0.39; 95% CI, 0.33 to 0.46; P<.0001), whereas ischemic stroke risk was higher (HR, 1.75; 95% CI, 1.17 to 2.64). Significant interactions were observed in subgroups with a history of ischemic stroke (P<.001) and of bleeding (P=.002). ConclusionAmong AF patients at high bleeding risk, our nationwide study highlights a high risk of clinical events during follow-up. LAAO appeared less effective than no LAAO in preventing stroke but more effective in preventing death. Left atrial appendage occlusion is particularly effective in patients with previous ischemic stroke or any episode of bleeding.

Comparison of cardiac function and structure after left atrial appendage occlusion without versus with ablation in patients with non-valvular atrial fibrillation: a retrospective study.

The Aim of this study was to investigate the long-term impact of left atrial appendage occlusion (LAAO) on cardiac function and structure in patients with non-valvular atrial fibrillation (NVAF). 157 patients with NVAF who underwent LAAO or combined with ablation were included and divided into simple LAAO group or combined group. Long term impact of LAAO on cardiac function and structure were evaluated. Results showed that the procedures were performed successfully with 6.4% complications. During follow-up, there was a significant decrease of left atrial anteroposterior diameter (LAAD) at 6 months and a significant increase of left ventricular end-diastolic dimension (LVEDD) at 12 months after LAAO. A significant decrease in plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) was noted at 3 months, 6 months and 12 months after procedure. There was a significant decrease of LAAD, LVEDD, left ventricular end-systolic dimension (LVESD) and NT-proBNP levels in combined group at 3 months, 6 months and 12 months post- procedure, while an increase of left ventricular ejection fraction (LVEF). Meanwhile, no significant change of LAAD, LVEDD, LVESD, NT-proBNP and LVEF was seen in simple LAAO group at 3 months follow-up, but a decrease of NT-proBNP during 6 months and 12 months follow-up. Compared with simple LAAO group, combined group was associated with a significant increase of residual flow. In conclusion, LAAO has no significant effect on cardiac structure and function but can significantly reduce NT-proBNP. The improvement of cardiac structure and function in combined therapy comes from the result of ablation, not LAAO.

Clinical outcome and intraprocedural characteristics of left atrial appendage occlusion: a comparison between single-occlusive plug-type and dual-occlusive disc-type devices.

Percutaneous interventional left atrial appendage occlusion (LAAO) is a reliable, safe, and effective alternative for stroke prevention in selected patients with atrial fibrillation (AF). In a retrospective observational study, 149 patients underwent LAAO between 2016 and 2022 at the Department of Cardiology of the Charité-Universitätsmedizin Berlin, Campus Virchow, with AF for prevention of thromboembolic complications. We compared patient characteristics, intraoperative details and postoperative outcomes between single-occlusive plug-type (SOPT) and dual-occlusive disc-type (DODT) devices. In all patients, the device implantation was successful. 60 patients received a SOPT occluder, including Watchman (35%) and Watchman FLX Occluders (65%), while 89 patients received a DODT occluder, including Amplatzer Cardiac Plug (37.1%), the Amplatzer Amulet (25.8%), and the LAmbre occluder (37.1%) systems. Procedure duration was significantly longer for DODT occluder implantation (49 ± 33 vs. 41 ± 25 min, p = 0.018). There were no in-hospital deaths or thromboembolic events reported after LAAO in both groups. Beyond that, a low rate of bleeding or access-side-related complications and pericardial tamponades were observed. Anticoagulation at discharge varied. About 60.8% of patients received dual antiplatelet therapy at hospital discharge, and 33.1% received direct oral anticoagulants. A 6-month follow-up was obtained in 85% of the patients. All implanted devices were in the desired position. However, in 5.7% of the patients, a device-related thrombus formation was detected in the SOPT group, while no thrombus was seen in the DODT group (p = 0.11). Thromboembolic events were noticed in 3.1%, without any difference between the device types. There was a statistically non-significant trend for less residual device leaks after SOPT vs. DODT implantation (no leak in 71.7% vs. 62.2%, p = 0.07; minor leaks <5 mm, 9.4% vs. 20.3%, p = 0.1). In the SOPT group, less bleeding complications were reported after LAAO (11.3% vs. 17.6%, p = 0.1). Our data suggest the safety and efficiency of LAAO with a very high procedural implantation success rate irrespective of the used LAA device. Furthermore, no relevant procedural or device-related complication occurred during the 6-month follow-up in all patients.

Anticoagulation Intensity during Appendage Occlusion: Lessons from Silent Cerebral Embolism

Introduction: Endovascular left atrial appendage occlusion (LAAO) is associated with a high incidence of peri-procedure silent cerebral embolism (SCE), while the recommended activated clotting time (ACT) level by the expert consensus is lower than that in atrial fibrillation (AF) ablation. The aim of our study was to investigate whether raising the targeted ACT level during LAAO to the same level as AF ablation could decrease the incidence of SCE. Methods: It was a prospective observational cohort study. Consecutive AF patients receiving LAAO between January 2021 and December 2022 were included and categorized into two groups based on the time of enrollment. Patients enrolled in 2021 (group 250) maintained a target ACT level of ≥250 s during LAAO procedure, while patients enrolled in 2022 (group 300) maintained the peri-procedure ACT ≥300 s. All patients underwent cerebral magnetic resonance imaging before and after the procedure. Results: A total of 81 patients were included (38 in the group 250 and 43 in the group 300). After inverse probability of treatment weighting (IPTW), patients in the group 250 showed a significantly lower incidence of SCE than group 300 (IPTW p = 0.038). Only a stable high ACT pattern could decrease the risk of SCE. No significant differences were found between other ACT change patterns on the SCE incidence. Conclusion: Raising the peri-procedure ACT level to a stable 300 s could decrease the risk of the SCE without increasing the major bleeding events.

Combining echocardiography and fluoroscopy imaging in real time for left atrial appendage occlusion - single center experience from Poland.

Atrial fibrillation (AF) presents a growing health concern, often requiring stroke prevention measures, primarily through oral anticoagulation (OAC). Surgical interventions such as left atrial appendage occlusion (LAAO) offer alternatives when OAC is contraindicated. In recent years, percutaneous procedures have gained traction as minimally invasive options, demanding precise anatomical insights. Fusion imaging (FI), which combines transesophageal echocardiography (TEE) and fluoroscopy, has emerged as a potential game-changer in transcatheter interventions. This study introduces FI to LAAO procedures in Poland, assessing its role in guiding interventions, highlighting advantages, and exploring its potential to reshape cardiovascular interventions. We conducted a retrospective study involving LAAO procedures from March 2015 to December 2018, all utilizing FI. Patient indications, procedural specifics, and safety metrics were collected and analyzed. Follow-ups were conducted at 3 and 6 months. A cohort of 83 patients (mean age: 72.1 ±8.4 years) underwent successful LAAO procedures. FI provided precise device placement and anatomical assessment. Mean procedure time was 54.9 ±34.3 min, contrast medium usage averaged 33.7 ±22.7 ml, and creatinine levels remained stable. Patients were discharged in about 4.2 ±3.4 days. Adverse effects were rare, including minimal bleeding and cardiac tamponade. Follow-ups demonstrated favorable outcomes with low adverse event rates. This study marks the inaugural application of FI in Polish LAAO procedures. FI, offering enhanced visualization and reduced procedure times, holds promise in improving patient safety and treatment efficacy. We recommend its consideration as a standard visualization technique for LAAO procedures.

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.

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

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. To investigate the incidence and predictors of device-related thrombus (DRT) in patients with AF who were treated with LAAC. 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. 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). 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.

Pushing boundaries in cardiac surgery: minimally invasive mitral valve repair combined with tricuspid valve repair and/or other concomitant procedures.

Minimally invasive mitral valve repair/replacement has emerged as a widely accepted surgical approach for managing mitral valve disorders. Continuous technological progress has contributed to the refinement of this procedure, leading to improved safety, decreased surgical trauma, and faster recovery times. Despite these advancements, there remains a scarcity of data concerning minimally invasive complex mitral valve repair surgeries when combined with additional procedures. Between November 2008 and December 2022, 153 patients underwent an operation using a minimally invasive technique. All patients underwent mitral valve surgery for severe mitral valve insufficiency/stenosis in combination with at least one additional procedure for tricuspid valve repair (n = 52, 34%), patent foramen ovale or atrial septal defect closure (n = 34, 22.2%), left atrial appendage occlusion (n = 25, 16.3%), or electrophysiological procedure (n = 101, 66.0%). Two concomitant procedures were conducted in 98 patients (64.1%), three concomitant procedures in 49 patients (32%), and four concomitant procedures in 6 patients (3.9%). Surgical success was achieved in 99.3% of the patients (n = 152), one patient required a revision of the mitral valve repair on the first postoperative day due to systolic anterior motion phenomenon. Mitral valve repair was performed in 136 patients (88.9%), while 15 patients (9.8%) received a mitral valve replacement as per a preoperative decision due to severe mitral valve stenosis, and two patients (1.3%) underwent other mitral valve procedures. Therapeutic success in treating atrial fibrillation was achieved in 86 patients (85.1%) of the 101 who received an additional maze-procedure. The 30-day mortality rate was 0.7%, with one patient succumbing to respiratory failure. Neurological complications occurred in 7 patients (4.6%). Freedom from reoperation was calculated as 98% at 5-year follow-up and 96.5% at 10-year follow-up. Minimally invasive mitral valve surgery, even when performed alongside concomitant procedures, stands out as a reproducible and safe technique with outstanding outcomes. It is imperative to advance towards the next frontier in minimally invasive surgery, encouraging experienced surgeons to undertake more complex procedures using minimally invasive approaches. These results help envision extending the boundaries of minimally invasive surgery by performing complex mitral valve procedures and associated interventions entirely through endoscopic means in suitable patients.

Pattern of Endothelialization in Left Atrial Appendage Occluder by Optic Coherence Tomography: A Pilot Study.

Implantation of the left atrial appendage occluder (LAAO) has been proven to prevent stroke effectively in patients with atrial fibrillation who cannot tolerate anticoagulants. Incomplete endothelization of LAAO may cause device-related thrombus, and currently no good image modality exists to clearly see LAAO endothelialization. We aimed to use coronary optic coherence tomography (OCT) to visualize LAAO endothelialization. We enrolled 14 patients (72.8±9.4 years old) undergoing pulmonary vein isolation with a preexisting LAAO implanted more than 1 year ago (5 Watchman and 9 Amulet). After pulmonary vein isolation, we did OCT via steerable sheath and coronary guiding catheter to adjust OCT probe location and injected contrast medium to visualize the LAAO surface. Invitro testing was also performed to see the bare occluder. Invitro OCT showed the surface of the bare device as an interrupted granule pattern, which included the Watchman surface polytetrafluoroethylene membrane string, Amulet disc metal strut, and inner polytetrafluoroethylene membrane string. In the implanted Watchman, OCT showed endothelialization as a smooth surface layer with noninterrupted coarser granules. In the implanted Amulet, OCT showed endothelialization as thin (early) or thick (late) endothelialization layer covering struts with OCT shadows. Among patients with Watchman, 2 showed no, 2 early, and 1 complete endothelialization. Among patients with Amulet, 2 showed no, 3 early, and 4 late endothelialization. We demonstrated the feasibility of OCT to visualize LAAO endothelization with high resolution. Further studies are needed to determine antithrombotic regimens if incomplete endothelization is detected. A new OCT catheter may be designed specifically for LAAO.