Left Atrial Appendage Device Research Articles

Left atrial appendage closure for stroke prevention in atrial fibrillation: current status and perspectives.

Atrial fibrillation (AF) is associated with an increased risk of stroke and systemic embolism, and the left atrial appendage (LAA) has been identified as a principal source of thromboembolism in these patients. While oral anticoagulation is the current standard of care, LAA closure (LAAC) emerges as an alternative or complementary treatment approach to reduce the risk of stroke or systemic embolism in patients with AF. Moderate-sized randomized clinical studies have provided data for the efficacy and safety of catheter-based LAAC, largely compared with vitamin K antagonists. LAA device iterations, advances in pre- and peri-procedural imaging, and implantation techniques continue to increase the efficacy and safety of LAAC. More data about efficacy and safety of LAAC have been collected, and several randomized clinical trials are currently underway to compare LAAC with best medical care (including non-vitamin K antagonist oral anticoagulants) in different clinical settings. Surgical LAAC in patients with AF undergoing cardiac surgery reduced the risk of stroke on background of anticoagulation therapy in the LAAOS III study. In this review, we describe the rapidly evolving field of LAAC and discuss recent clinical data, ongoing studies, open questions, and current limitations of LAAC.

Pericardial Effusion After Left Atrial Appendage Closure: Timing, Predictors, and Clinical Impact

BackgroundPericardial effusion (PE) is the most common serious left atrial appendage closure (LAAC) complication, but its mechanisms, time course, and prognostic impact are poorly understood. ObjectivesThis study sought to assess the frequency, timing, predictors and clinical impact of PE after LAAC. MethodsData on consecutive patients undergoing percutaneous LAAC between 2009 and 2022 were prospectively collected including the 1-year follow-up. Both single (Watchman 2.5/FLX, Boston Scientific) and double (Amplatzer Cardiac Plug or Amulet, St. Jude Medical/Abbott) LAAC devices were used. An imaging core laboratory adjudicated the PEs and categorized them as early (≤7 days) and late (8-365 days). Logistic regression analysis was used to identify predictors of early and overall PE. ResultsOf 1,023 attempted LAAC procedures, PE was observed in 44 (4.3%) patients; PE was categorized as early in 34 (3.3%) and late in 10 (0.9%) patients. The majority of PEs occurred within 6 hours after LAAC (n = 25, 56.8%) and were clinically relevant (n = 28, 63.6%). Independent predictors of early PE were double-closure left atrial appendage devices (adjusted OR: 8.20; 95% CI: 1.09-61.69), female sex (adjusted OR: 3.41; 95% CI: 1.50-7.73), the use of oral anticoagulation (OAC) at baseline (adjusted OR: 2.60; 95% CI: 1.11-6.09), and advanced age (adjusted OR: 1.07; 95% CI: 1.01-1.23), whereas female sex and OAC at baseline remained independent predictors of overall PE. ConclusionsIn this large LAAC registry, PE was observed in <1 in 20 patients and usually occurred within 6 hours after procedure. The majority of early PEs were clinically relevant and occurred in the Amplatzer Cardiac Plug/Amulet procedures. Independent predictors included the use of double-closure devices, female sex, OAC at baseline, and advanced age. (LAAC-registry: Clinical Outcome After Echocardiography-guided LAA-closure; NCT04628078)

Two‐Year Outcomes With a Next‐Generation Left Atrial Appendage Device: Final Results of the PINNACLE FLX Trial

Background The PINNACLE FLX (Protection Against Embolism for Non-valvular AF [Atrial Fibrillation] Patients: Investigational Device Evaluation of the Watchman FLX LAA [Left Atrial Appendage] Closure Technology) trial evaluated the safety and efficacy of a next-generation left atrial appendage closure device (WATCHMAN FLX; Boston Scientific, Marlborough, MA). At 1 year, the study met the primary end points of safety and anatomical efficacy/appendage closure. This final report of the PINNACLE FLX trial includes the prespecified secondary end point of ischemic stroke or systemic embolism at 2 years, also making it the first report of 2-year outcomes with this next-generation left atrial appendage closure device. Methods and Results Patients with nonvalvular atrial fibrillation with CHA2DS2-VASc score ≥2 (men) or ≥3 (women), with an appropriate rationale for left atrial appendage closure, were enrolled to receive the left atrial appendage closure device at 29 US centers. Adverse events were assessed by an independent clinical events committee, and imaging was assessed by independent core laboratories. Among 395 implanted patients (36% women; mean age, 74 years; CHA2DS2-VASc, 4.2±1.5), the secondary efficacy end point of 2-year ischemic stroke or systemic embolism was met, with an absolute rate of 3.4% (annualized rate, 1.7%) and an upper 1-sided 95% confidence bound of 5.3%, which was superior to the 8.7% performance goal. Two-year rates of adverse events were as follows: 9.3% all-cause mortality, 5.5% cardiovascular death, 3.4% all stroke, and 10.1% major bleeding (Bleeding Academic Research Consortium 3 or 5). There were no additional systemic embolisms, device embolizations, pericardial effusions, or symptomatic device-related thrombi after 1 year. Conclusions The secondary end point of 2-year stroke or systemic embolism was met at 3.4%. In these final results of the PINNACLE FLX trial, the next-generation WATCHMAN FLX device demonstrated favorable safety and efficacy outcomes.

Abstract 9688: Isoproterenol Assisted Differentiation Between Sludge and Organized Thrombus of Left Atrial Appendage to Help Guide Percutaneous Closure

Background: Percutaneous left atrial appendage (LAA) closure is contraindicated in patients with LAA thrombus. It can be challenging to distinguish slow flow (sludge) from organized thrombus on echocardiography. Recent case reports have shown that isoproterenol infusion can distinguish LAA sludge from thrombus, however, no mid/long-term outcome data exists. Methods: A retrospective study was conducted on 32 patients who underwent Watchman™ implantation at Piedmont Atlanta Hospital during 2021. Patients were divided into two groups, 1) clear LAA [Standard] and 2) suspected LAA thrombus versus sludge [Sludge]. The Sludge group underwent isoproterenol infusion prior to implantation of Watchman™ device. Data gathered included demographics, medical history, procedural data, and 6-months outcomes defined as TIA, CVA, or device related thrombus. Chi-square and T-test was used for statistical analysis. Results: The cohort had 8 patients (25%) in Sludge group with remaining 24 patients (75%) in Standard group. The Sludge group was younger at 73.5 years compared to 77.0 years for Standard group [p=0.02]. Other baseline characteristics including sex, comorbidities, and history of prior TIA/CVA were similar among both groups. Median CHA 2 DS 2 VASc Score was 5.0 for Standard and 4.5 for Sludge group [p= 0.21]. All patients in Sludge group had successful clearance with isoproterenol; median dose required was 6 mcg. LAA dimensions were similar with the median device size being 27 mm for both groups [p= 0.343]. At 45-day follow-up, one patient in Standard group had device related thrombus; it resolved on subsequent scan. At 6-months, one patient in Sludge group had experienced TIA; no patients underwent CVA. Conclusions: LAA thrombus is an absolute contraindication for percutaneous LAA device implantation, however, it can be difficult to differentiate between sludge and organized thrombus. This study demonstrates that intraprocedural isoproterenol infusion can be used to clear LAA sludge by improving LV contractility. No significant difference in mid-term outcomes was observed in our study groups, suggesting that isoproterenol assisted differentiation of LAA sludge from thrombus may allow successful LAA closure in cases that are deemed to have LAA sludge.

Causes and predictors of immediate and short-term readmissions following percutaneous left atrial appendage closure procedure.

Percutaneous left atrial appendage device closure has been offered as an alternative to anticoagulation for high-risk patients with nonvalvular atrial fibrillation. Given the relative novelty of the procedure, we aimed to analyze the rates and causes of immediate (30 days) and short-term (90 days) readmission after the procedure. We performed a retrospective observational study using the Nationwide Readmissions Database for 2018. We studied 29 449 hospitalizations for percutaneous left atrial appendage (LAA) device closure. In both the 30- and 90-day cohorts, the most common causes of readmissions were gastrointestinal bleeding (16.1% and 14.8%), heart failure exacerbation (11.1% and 11.6%), and atrial fibrillation (6.2% and 7.2%). Female sex, liver disease, chronic kidney disease, chronic pulmonary disease, presence of heart failure,human immunodeficiency virus/acquired immunodeficiency syndrome status, and diabetes mellitus were independently associated with higher odds of readmission in both cohorts. Our study highlights the need for further deliberation on the choice and duration of anticoagulation periprocedurally after percutaneous LAA closure, especially among those with high bleeding risk. It also highlights the need for optimization of heart failure status periprocedurally to avoid readmissions for exacerbations.

Cardiac Computed Tomography Angiography for Device-Related Thrombus Assessment After WATCHMAN FLX™ Occluder Device Implantation: A Single-Center Retrospective Observational Study

Background/purposeDevice-related thrombosis (DRT) is one of the greatest challenges of transcatheter left atrial appendage device occlusion. Due to the invasive nature of transesophageal echocardiography (TEE), cardiac computed tomography angiography (CCTA) is being increasingly utilized in several centers for assessing adequate left atrial appendage closure and monitoring for DRT. There is a paucity of data regarding the standardized definition of DRT on CCTA for the WATCHMAN FLX™ device. Methods/materialsA retrospective review was conducted on 43 patients receiving WATCHMAN FLX™ device implantation with CCTA performed at the first follow-up at our institution. A comparative review of DRT predictors was performed on 10 patients who had both CCTA and TEE at the time of follow-up. ResultsHypoattenuated thickening (HAT) was a common finding on CCTA and was noted to be present in 95.35% of the patients. The combination of a large device size, peridevice gap >4 mm, and HAT located on the device gutter and 1 shoulder were characteristics present on CCTA observed in 2 patients with confirmed DRT on TEE. ConclusionCCTA is a noninvasive imaging modality for DRT monitoring, with guidelines still in development. We report potential predictors of DRT on CCTA. Additional studies are needed to further determine standardized parameters for DRT detection on CCTA and the significance of HAT with multimodality correlation.

475 Is left atrial appendage device compression rate a predictor of incomplete occlusion in patients undergoing watchman device implantation?

Abstract Aims Transesophageal echocardiography (TEE) is a standard peri-procedural imaging modality in patients undergoing percutaneous left atrial appendage (LAA) occlusion. An accurate device sizing is pivotal to assess stability and achieve successful closure. In this prospective study, we sought to evaluate the correlation between Watchman device compression rates (DCRs) and risk of incomplete LAA occlusion at follow-up in patients undergoing Watchman device implantation. Methods and results Two-dimensional TEE via a commercially available transducer (Vivid, Philips) was performed during the procedure and within 3 months after the procedure. LAA size, morphology, and DCRs [(original device size—size after deployment)/original device size; %] were assessed in a mid-oesophageal view at 0°, 45°, 90° and 135°, according to company recommendations. Residual leaks ≥ 3 mm were classified as significant. Between 2016 and 2018, 116 patients underwent LAA occlusion with a Watchman device at our institution. The mean age was 74 ± 9 years and 60.4% (n = 70) were males. The average CHA2DS2-VASc and HAS-BLED scores were 4.7 ± 1.7 and 2.5 ± 1.1, respectively. The final device size was 21 mm in 11 (9.5%) patients, 24 mm in 28 (24.1), 27 mm in 27 (23.3%), 30 mm in 26 (22.4%), and 33 mm in 24 (20.7). At follow-up TEE, 16 (13.8%) patients were found to have a significant (≥3 mm) residual leak. The average DCRs measured at different angles in patients with and without leak were not significantly different (24 ± 8% vs. 26 ± 7% at 0°, P = 0.47; 23 ± 9% vs. 25 ± 7% at 45°, P = 0.58; 23 ± 8% vs. 23 ± 6% at 90°, P = 0.61; 22 ± 8% vs. 21 ± 7% at 135°, P = 0.61). At receiver operating characteristic (ROC) analysis, the areas under the curve to discriminate between patients with/without leak were 0.58, 0.57, 0.55, and 0.46 for DCRs measured at 0°, 45°, 90°, and 135° angles. Conclusions Peri-procedural assessment of DCRs does not appear to be an accurate method to predict LAA complete occlusion in patients undergoing Watchman device implantation.

B-AB17-01 LEFT ATRIAL CLOSURE DEVICE THROMBOSIS IS ASSOCIATED WITH SYSTEMIC EMBOLIZATION

Cardioembolic stroke and systemic embolism (CS/SE) represents the most severe complication of atrial fibrillation. Approximately 92% of intracardiac thrombosis originates from the left atrial appendage (LAA) and, although its mechanical occlusion is a proved method to prevent cardioembolism, thrombosis of all types of LAA occlusion devices and their associations with CS/SE were observed. The purpose of this study is to evaluate the rate of LAA occlusion device thrombosis, its predictors, and the risk for cardioembolism. We analyzed a group of 454 patients (65% male, mean age 72 years) with high risk for thromboembolism (mean CHADSVASc=4.0) after LAA catheter occlusion using any of 9 different occluder types since 2004. During clinical follow-up 1260 patient years were collected and an intracardiac thrombus was found on 24 devices. Total of 18 patients suffered CS/SE. Thrombosis was found in 11 men and 12 women, mean age 76 years, average CHADSVASc=4.5 and HASBLED=2.0. The thrombus was discovered on average 4.1 months after the LAA occlusion. In that time patients were receiving dual antiplatelet therapy (13x), acetylsalicic acid (6x), or interrupted anticoagulation (5x). In 3 cases the thrombosis was associated with CS/SE which represented risk of 6.6% per year. In patients with no thrombosis annual risk of CS/SE was only 1.7% (P<0.001). In our single center register thrombosis was found in total of 5.7% patients after LAA device implantation. In these patients, risk of CS/SE is 3.9-fold higher compared to patients without thrombus formation. Elderly patients and patients with more risk factors in general were affected more frequently.

Abstract 14782: Sex Comparisons in Anticoagulation Treatment for Atrial Fibrillation in a Large Rural Healthcare System

Introduction: Atrial fibrillation (AF) and flutter lead to increased risk of thromboembolism (TE). The CHA 2 DS 2 -VASc score is used to determine the risk of TE. Objective: We aim to evaluate the anticoagulation use across CHA 2 DS 2 -VASc scores calculated using a validated automatic calculator. Methods: An AF registry was created for patients with AF or atrial flutter who had seen a primary care or cardiology provider within the past 2 years (5/28/2018-5/28/2020). An automatic CHA 2 DS 2 -VASc calculator was integrated into the electronic medical record system at Essentia Health on 10/1/2019. High-risk of TE was defined as a score of ≥3 for females and a score of ≥2 for males. AF registry included demographics, anticoagulation prescription, CHA 2 DS 2 -VASc and ATRIA bleed score, contraindications, and presence of left atrial appendage (LAA) occlusion device. Results: A total of 10992 patients with AF or atrial flutter were included in the registry (74.8 ±11.8 years, 41.7% female). A total of 6703 (61.0%) had a CHA 2 DS 2 -VASc score calculated (mean score 3.9 ± 1.5). Mean ATRIA bleed score was 3.0 ± 2.0. Within these patients, 90.7% of males and 93.0% of females were at high-risk of TE. Of these high-risk patients, anticoagulation use was 82.7% for females and 83.5% for males and increased with increasing score (p&lt;0.01 for males, p&lt;0.01 for females) (Figure 1). Overall, 36.9% were prescribed NOAC, 47.0% warfarin, and 0.8% heparin. There was no sex difference in the prescription of NOAC (37.7% male vs. 35.9% female, p=0.1). Fewer than 1% had WATCHMAN LAA device (0.3% male vs. 0.4% female, p=0.5). Conclusion: Four out of 5 patients at increased risk of TE are prescribed an anticoagulant. Interventions to improve anticoagulation use in high-risk patients are needed. Figure 1. Anticoagulation prescription use in atrial fibrillation patients by CHA 2 DS 2 -VASc score and sex between 5/28/2018-5/28/2020 at Essentia Health (N=6703).

Unconventional combination of left atrial appendage device occlusion in patients with atrial fibrillation who needed concomitant catheter interventions for underlying structural heart disease

ObjectivesLeft atrial appendage occlusion (LAAO) in non-valvar atrial fibrillation (AF) reduces cardioembolic strokes. Despite increased risk, trials exclude valvar AF in structural heart diseases where clots extend beyond appendage. MethodsPatients with AF and relative risks for oral anticoagulation (OAC) needing structural interventions underwent concomitant LAAO. After six months of OAC, aspirin was continued. Transesophageal echocardiogram was done three monthly till one year and yearly thereafter. The patient demographics, procedural details, post-procedural follow-up were analyzed. ResultsNine patients aged 51.5 ± 6.3 years with AF underwent LAAO concomitantly with balloon mitral valvotomy in four patients, atrial septal defect device closure in four and periprosthetic mitral leak closure in one patient. Six patients had heart failure, four had prior embolic events, and two had documented LAA thrombus. The mean CHADS2VASc score was 2.44 ± 0.8 and mean HASBLED score was 3.0 ± 0.8. Devices included Amplatzer Cardiac Plug™ in six patients, LAmbre™ Lifetech device in two and Watchman™ device in one. All procedures were successful without acute complications. A patient developed pericardial effusion at six months requiring pericardiocentesis. Early device-associated thrombus in one patient resolved after OAC for six months. No embolic events occurred on follow-up. ConclusionOn a detailed literature search, this largest LAAO experience in structural heart diseases indicates its utility. OAC for six months followed by aspirin seems to prevent thrombus formation in these patients. The only incidence of early thrombus formation indicates immunity from clot formation after device endothelialisation. Larger multicenter trials combining LAAO with structural interventions in valvular AF are warranted in developing nations.

P1799 The importance of 3D imaging techniques in left atrial appendage closure: landing zone eccentricity influence on peri-device leak incidence and its implication in long-term clinical outcomes

Abstract Background A complex left atrial appendage (LAA) morphology and a non-circular landing zone (LZ) are frequently encountered in patients undergoing percutaneous LAA occlusion (LAAO). Three-dimensional (3D) imaging modalities as 3D transoesophageal echocardiography (3D TOE) and cardiac computed tomography (CCT) should be preferred over two dimensional techniques for better evaluation of LAA diameters, especially for the LZ. In fact, non-circular shape could impair the choice of occluder device size and may be implicated in the occurrence of residual leaks. Incomplete LAA occlusion is recognized to be associated with thromboembolic events. Purpose The aim of the study was to evaluate the utility of 3D imaging techniques to predict LAA device size and the landing zone eccentricity index as a potential predictor of residual peri-device leaks and to assess their clinical implications on long-term follow-up. Methods It was a retrospective, single-center study including 137 consecutive patients undergoing successful LAAO from January 2010 to July 2018. Pre-procedural 3D TOE and CCT were used to predict device size based upon LZ diameters and quantify LAA orifice eccentricity. Leaks were defined as the presence of peri-device flow at 2D TOE immediately after the device implantation and at 3 months follow-up. Leaks were classified as significant (color jet width ≥4 mm) or minor (&amp;lt;3 mm). A clinical evaluation of thromboembolic events was performed at 48 ± 27 months from the procedure. Results LAAO closure was performed implanting either Amulet or Watchman devices (n = 98 and n = 40, respectively). The assessment of LZ measurements with 3D TOE and CCT showed a significant correlation with the device size selected on the basis of 2D techniques (r = 0.82 and r = 0.74, respectively). As concerns the peri-device leaks, the presence of an eccentric LZ (eccentricity index &amp;gt;0.20) was not associated to the development of post-procedural leaks in the overall population; a significant correlation was detected only in the subgroup of patients treated with the Amulet device (p = 0.045). Residual leaks included only 1 significant leak (0.7%) after Amulet device implantation, which was related to a major neurological event (stroke) and 47 (34%) minor leaks (n = 28 in the Amulet group, n = 19 in the Watchman group). In this last population, 2 patients (1.5%) developed minor neurological events (transient ischemic attack). Conclusions 3D TOE and CCT better predict device size overcoming the limit of 2D imaging techniques undersizing. In eccentric LAA, Watchman device may reduce the incidence of peri-device leaks. The presence of significant residual leaks is uncommon but associated with major clinical events, whilst minor leaks are relatively frequent but do not seem to be related to life-threatining thromboembolic accidents.

P998Left atrial appendage closure device thrombosis is associated with systemic embolization

Abstract Introduction Atrial fibrillation, in one of its forms, is the most frequent sustained tachyarrhythmia and increases the risk of stroke more than 5 times. Cardioembolic stroke and systemic embolism (CS/SE) represents the most severe complication of this arrhythmia. Approximately 92% of intracardiac thrombosis originates from the left atrial appendage (LAA) and, although its mechanical occlusion is proved method to prevent cardioembolism, thrombosis of all types of LAA occlusion devices and their associations with CS/SE were observed. The purpose of this study is to evaluate the rate of LAA occlusion device thrombosis, its predictors and the risk for cardioembolism. Methods We analyzed a group of 359 patients (65% male, mean age 72 years) with high risk for thromboembolism (mean CHADSVASc = 4.0) after LAA catheter occlusion using any of 9 different occluder types since 2005. During clinical follow-up 819 patientyears were collected and an intracardiac thrombus was found on 22 devices. Total of 17 patients suffered CS/SE. Results Thrombosis was found in 11 men and 11 women, mean age 76 years, average CHADSVASc = 4.5 and HASBLED = 2.0. The thrombus was discovered on average 4.0 months after the LAA occlusion. In that time patients were receiving dual antiplatelet therapy (11x), acetysalicic acid (4x), or interrupted anticoagulation (6x). In 3 cases the thrombosis was associated with CS/SE which represented risk of 6.6% per year. In patients with no thrombosis annual risk of CS/SE was only 1.7% (P&lt;0.001). Figure 1 Conclusion In our single center register thrombosis was found in total of 6.3% patients after LAA device implantation. In these patients, risk of CS/SE is 3.9-fold higher compared to patients without thrombus formation. Elderly patients and patients with more risk factors in general were affected more frequently.

Left atrial appendage device closure: effective alternative to oral anticoagulants for nonvalvular AF in selected patients

Left atrial appendage device closure: effective alternative to oral anticoagulants for nonvalvular AF in selected patients

Feasibility of left atrial appendage device closure following chronically failed surgical ligation

Incomplete surgical left atrial appendage occlusion (S-LAAO) with a narrow neck has been shown to predict an increased rate of embolic stroke. Patients with a previously attempted S-LAAO were systematically excluded from all clinical trials of LAA closure devices. The purpose of this study was to evaluate the feasibility of Watchman LAA device closure for patients referred with chronically incomplete S-LAAO. A prospective single-arm feasibility cohort evaluated only subjects undergoing Watchman LAA closure following incomplete S-LAAO. Patients referred and implanted were followed in the Vanderbilt LAA Registry. Preprocedure computed tomographic angiography and transesophageal echocardiography (TEE) were performed to evaluate suitability for closure, with 45-day follow-up TEE postimplant. All attempted LAA closures after incomplete S-LAAO were successful (n = 6). Mean age was 76.3 ± 7 years. Mean CHADS2Vasc score was 3.8 ± 0.8, and HAS-BLED score was 3.5 ± 0.5. At 45-day follow up, all subjects had complete device seal with no thrombus on device and had transitioned to clopidogrel plus aspirin. Three subjects had narrow ostial necks with a maximum diameter ≤9mm. In all cases, the 4.7-mm Watchman access sheath was able to cross the ostial stricture. Mean occluder size implanted was 28 ± 4 mm. Mean LAA dimension by TEE in the 45° and 135° views for depth was 31 mm and ostial diameter was 11 × 16 mm, below the minimum Watchman indication for use of 17 mm. No major intraoperative complications occurred. Watchman LAA closure seems to be feasible in patients with chronically incomplete S-LAAO, including subjects with a narrow neck ≤9 mm in width.

Surgical Closure of the Left Atrial Appendage: The Past, The Present, The Future.

Occlusion of the left atrial appendage (LAA) may protect against stroke in patients with atrial fibrillation. While percutaneous LAA closure devices have demonstrated efficacy in stroke reduction, surgical LAA occlusion has been performed with mixed results to date. Although surgical exclusion via internal sutures or noncutting stapler is ineffective due to recanalization of the LAA, surgical excision and certain exclusion devices including the AtriClip device are effective methods to achieve complete closure of the LAA. No data currently exists to support routine, prophylactic LAA closure at the time of cardiac surgery, but this practice may benefit certain patients at high risk for stroke. The currently enrolling Left Atrial Appendage Occlusion Study (LAAOS) III is the largest study to date designed to assess the efficacy of LAA occlusion for stroke prevention. The results of this trial will inform future clinical practice regarding stroke prevention with surgical LAA occlusion for patients with atrial fibrillation. Meanwhile, the ATLAS trial is investigating the efficacy of LAA occlusion in surgical patients who do not have atrial fibrillation but are at increased risk for developing it post-operatively.

Left Atrial Appendage Closure and Systemic Homeostasis: The LAA HOMEOSTASIS Study

BackgroundThe impact of left atrial appendage (LAA) exclusion, comparing an epicardial LAA or an endocardial LAA device, on systemic homeostasis remains unknown. ObjectivesThis study compared the effects of epicardial or endocardial LAA devices on the neurohormonal profiles of patients, emphasizing the roles of the renin-angiotensin-aldosterone system and the autonomic nervous system. MethodsThis is a prospective, single-center, observational study including 77 patients who underwent LAA closure by an epicardial (n = 38) or endocardial (n = 39) device. Key hormones involved in the adrenergic system (adrenaline, noradrenaline), renin-angiotensin-aldosterone system (aldosterone, renin), metabolic system (adiponectin, free fatty acids, insulin, β-hydroxybutyrate, and free glycerols), and natriuresis (atrial and B-type natriuretic peptides) were assessed immediately before the procedure, immediately after device deployment, at 24 h, and at 3 months follow-up. ResultsIn the epicardial LAA device group, when compared with baseline blood adrenaline, noradrenaline and aldosterone were significantly lower at 24 h and 3 months (p < 0.05). There was no significant change in levels post-endocardial LAA device implantation. After epicardial LAA device implantation, there were significant increases in adiponectin and insulin, with decreased free fatty acids at 3 months. There was no significant change in these levels post-endocardial LAA device. N-terminal pro-A-type natriuretic peptide and N-terminal pro-B-type natriuretic peptide were significantly decreased in the acute phase after epicardial LAA device implantation, which subsequently normalized at 3 months. Post endocardial LAA device implantation, the levels increased immediately and normalized after 24 h. Systemic blood pressure was also significantly lower at all time points after epicardial LAA device implantation, which was not seen post-endocardial LAA device implantation. ConclusionsThere are substantial differences in hemodynamics and neurohormonal effects of LAA exclusion with epicardial and endocardial devices. Further studies are required to elucidate the underlying mechanism of these physiological changes.

Abstract 21337: Comparison of Cardiac Computerized Tomography Angiography and Transesophageal Echocardiography for Device Surveillance After Endovascular Left Atrial Appendage Closure

Background: Surveillance after left atrial appendage (LAA) closure is important to assess for device success and complications. There is limited data on the role of cardiac computerized tomography angiography (CCTA) for LAA device monitoring. Methods: We retrospectively analyzed consecutive patients with non-valvular atrial fibrillation who underwent LAA closure who had both trans-esophageal echocardiography (TEE) and CCTA performed post-LAA closure. Prospective cardiac-gated CCTA were performed with Toshiba 320-detector or Siemens 2nd generation 128-slice dual-source scanners. We assessed for residual contrast patency of the LAA by comparing linear attenuation coefficient (Hounsfield unit, HU) in the LAA and left atrium (LA) on CCTA. Residual contrast patency was categorized as due to peri-device leak (presence of ostial gap) or fabric leak (diffusion of contrast through device membrane). We also assessed for device compression, thrombus and pericardial effusion on CCTA. These were compared to TEE findings. Results: Sixty-one patients underwent CCTA at median 93.5d (1-267) post-LAA closure (55 WATCHMAN, 4 Amulet, 2 ACP). Post-procedural TEE was done at median 93d (0-289). The median age was 77.5yrs (60-88) and median CHADS-VASc score 4 (2-8). Procedural success was 100%. On TEE, the presence of any peri-device leak was 26 (41.9%), with &gt;3mm leak observed in 10/62 (16.1%), and &gt;5mm observed in none. The presence of residual contrast patency in the LAA was observed in 36/61 (59%) on CCTA, of these, 29 (80.5%) had peri-device leak, and 7 (19.4%) had fabric leak. The median linear attenuation coefficient in patients with residual contrast patency was 328 (133-652) HU, and all had &gt;100 HU in the LAA and HU attenuation ratio LA/LAA of &gt;0.25. Median maximum device compression was 5.7% in those with peri-device leak, and 19.4% (p=0.027) for those without peri-device leak on CCTA. Among patients with peri-device leak on CCTA, 89.6% had peri-device leak on TEE, with corresponding 93.8% sensitivity, 69.9% specificity, and AUC=0.82 (95% CI 0.72-0.93). Conclusions: CCTA is more sensitive than TEE for assessing peri-device leak after LAA closure. Greater device compression appears to be associated with lower incidence of peri-device leak.

TCT-101 Safety of double antiplatelet therapy as an alternative to warfarin plus aspirin after left atrial appendage device closure - short-term results of WATCHMAN-DAPT multi-center registry

The safety of dual antiplatelet therapy (DAPT) as an alternative to warfarin plus aspirin after transcatheter closure of left atrial appendage (LAA) with a Watchman device (Boston Scientific, USA) is not well established. 272 subjects, 99 women (39.9%), on DAPT (clopidogrel 75 mg q.d. plus apirin

A comparative study of different imaging modalities for successful percutaneous left atrial appendage closure

ObjectivesAccurate sizing of the left atrial appendage (LAA) is essential when performing percutaneous LAA closure. This study aimed to compare different LAA imaging modalities and sizing methods in order to...

Dealing With the Left Atrial Appendage for Stroke Prevention: Devices and Decision-Making.

Left atrial appendage (LAA) device occlusion represents a major evolution in stroke prevention for atrial fibrillation (AF). Left atrial appendage device occlusion is now a proven strategy which provides long-term thromboembolic stroke prevention for patients with non-rheumatic AF. Evidence supports its benefit as an alternative to long-term anticoagulation while mitigating long-term bleeding risks and improving cardiovascular mortality. The therapy offers expanded options to physicians and patients negotiating stroke prevention (both primary and secondary prevention), but a good understanding of the risks and benefits is required for decision-making. This review aims to summarise the evolution of LAA device occlusion therapy, current knowledge in the field and a snapshot of current status of the therapy in clinical practice in Australia and around the world.