Underwent Left Atrial Appendage Closure Research Articles

Abstract 4143224: Feasibility of Left Atrial Appendage Occlusion with Dual-Seal Technology without Pre-Procedural CT: Early Single-Center Experience

Background: Left Atrial Appendage (LAA) Occlusion with Amulet has shown promising results in achieving complete closure with minimal periprocedural leak. Amulet’s dual-sealed technology and numerous sizing options provide versatility for different LAA morphologies. Pre-procedural CT is routinely recommended for pre-procedural planning. However, this brings risks including use of contrast, risk of renal failure, radiation exposure, and patient inconvenience. Here, we share initial results of our Amulet implantation protocol without pre-procedural CT: 83 cases were reviewed; number of devices used, procedural time, periprocedural bleeding complications, success in coming off oral anticoagulation, and incidences of stroke and embolism were followed. Methods: We followed 83 AF patients who underwent LAA closure with Amulet, implanted with intraprocedural TEE, intracardiac left atrial echocardiography, and intraprocedural angiography. Pre-procedural CT was not used. Patients were followed to assess safety and efficacy of this protocol. Safety endpoints included rates of procedural and bleeding complications. Efficacy endpoints included rates of stroke and embolism, and number of devices used. Results: All 83 procedures were successfully completed with no perioperative procedural complications and no documented leaks on follow-up TEE. Patients had early ambulation with closure. On average, 1.14 devices were used per case: 88% of cases required 1 device, and nine cases required 2 devices; one case required 4 devices to fit as patient was noted to have an interrupted IVC, requiring implantation via right IJV. There were no cases of stroke or embolism following implantation, and all patients were safely able to come off oral anticoagulation. Conclusions: Results demonstrate that Amulet with its dual-sealed technology can be effectively and safely implanted without pre-procedural CT. No perioperative complications were observed. 88% of cases closed with single device usage. No post-procedure leaks were noted on follow-up TEE. Safety endpoints revealed minimal adverse events, with 2 cases of late pericardial effusion managed without long-term consequences. This protocol demonstrated high efficacy, as all patients were successfully able to come off oral anticoagulation with no reported strokes or embolic events. Intraprocedural TEE, intracardiac left atrial echocardiography, and intraprocedural angiography are typically appropriate for periprocedural sizing of the device.

Innovative Surgical Left Atrial Appendage Closure Technique: Early Experience of Inverted Spiral Closure Technique.

Simultaneous closure of the left atrial appendage (LAA) during cardiac procedures has become a common preventive measure against cardiogenic embolic events associated with atrial fibrillation. However, this strategy encounters limitations during minimally invasive mitral valve surgery through a right minithoracotomy because access to the LAA is limited. The use of endocardial sutures for surgical exclusion of the LAA is also well established but has a notable rate of closure failure. We introduced a new surgical LAA closure technique called the inverted spiral closure technique (ISCT). Between July 2020 and August 2021, 26 patients underwent LAA closure with ISCT concomitant to mitral valve surgery in our hospital. Early postoperative outcomes and any stroke or thromboembolic event during the follow-up were evaluated. Transthoracic or transesophageal echocardiography (TEE) was used to assess LAA patency. The ISCT procedure was performed successfully in all cases. No significant persistent flow between the left atrium and LAA was observed on intraoperative TEE. During a median follow-up of 1.1 years, no patients experienced stroke, myocardial infarction, or death. Postoperative echocardiography showed no significant residual flow within the LAA. One patient was incidentally found to have recanalization between the left atrium and LAA several months after surgery on an enhanced computed tomography scan during coronary evaluation. The ISCT can be performed reliably through the same left atriotomy for mitral valve surgery and is a useful and effective technique for surgical LAA exclusion. There are still not enough patients and modalities for postoperative evaluation.

Percutaneous left atrial appendage closure using a novel occlusion device for thromboembolic prevention: 3-year procedural experience

Abstract Background Stroke due to atrial fibrillation has been associated with a high risk of disability and mortality. Percutaneous left atrial appendage (LAA) closure has been established as a treatment strategy for stroke prevention in patients not eligible for oral anticoagulation as well as in patients after electrical isolation of the LAA and subsequent increased risk of thrombus formation. The aim of this study was to evaluate the feasibility and initial experience of LAA closure using a novel nitinol-based, self-expanding system in an unselected patient cohort. Methods and Results One hundred and two patients (39% female, median age 75 [71;80], median CHA2DS2-VASc score 5 [4;6]) underwent LAA closure with the novel system between October 2020 and October 2023. 61/102 (61%) patients underwent previous electrical LAA isolation, 30/102 (29%) patients had high bleeding risk as an indication for LAA closure. Median procedure time was 45 [38;59] minutes and median fluoroscopy time was 10 [7;12] minutes. Successful LAA closure was achieved in all patients, despite different LAA anatomies. Median umbrella and cover disc diameter were 22 [20;24] millimeter and 28 [20;24] millimeter, respectively. Procedure-related adverse events occurred in 2/111 (1.8%) patients. One patient had a vascular complication at the puncture site and another patient had non-hemodynamically significant pericardial effusion. Overall, the patients stayed for a median of 2 [1;4] days in hospital. Conclusion Left atrial appendage closure with a novel nitinol-based, self-expanding system is feasible and safe. LAA isolation was the most common indication for LAA closure at our institution. Further studies are needed, to identify differences and potential advantages of different LAA closure systems.

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

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

The predictive value of compression rate on residual leak after left atrial appendage occlusion with watchman FLX

Abstract Background Incomplete left atrial appendage (LAA) occlusion due to residual leaks may occur after percutaneous closure procedure with Watchman FLX. Before release of device PASS (position, anchor, size and seal) criteria must be verified. Optimal compression rate for watchman FLX device is between 10-30% according to company recommendations. Purpose The aim of this study is to evaluate the correlation between compression rate and leak presence after left atrial appendage closure. Methods This is an observational retrospective study including patients that underwent LAA closure under transesophageal echocardiography (TEE) with at least one follow-up where complete LAA closure was assessed by TEE in our center between January 2021 and August 2022. TEE images were reviewed by the first author. Compression rate was calculated based on intraprocedural TEE images using the following formula: (original device size—size after deployment)/original device size*100. Patients were divided into 2 groups based on the compression rate: group 1: 10-30%; group 2: >30%. The rate of leak between groups was compared using the Chi-square test. Results 203 patients (mean age 79± 8 years) were included in the study. The implanted device size was 20 mm in 7 (3.4%), 24 mm in 30 (14.8%), 27 mm in 49 (24.1%), 31 mm in 75 (36.9%) and 35 mm in 42 (20.7%) patients. Based on the compression rate, patients were classified into group 1: >30% [n=37 (18.2%)] and group 2: ≤30% [n=166 (81.8%)]. Mean compression rate was 38.5% and 21.3% in group 1 and 2 respectively. At follow-up TEE, 1 (2.7%) patient in group 1 and 32 (19.3%) patients in group 2 were found to have a residual leak of >1 mm. When comparing leaks between the two groups, there was 1 leak in group 1 whereas in group 2 there were 32 leaks (1/37 vs 32/166, p value 0.01, RR 0.14, 95% CI, 0.02-0.74). Conclusion Devices with compression rate ≤30% were associated with significantly higher risk of residual leak.

PO-03-168 IMPORTANCE OF COMPRESSION RATE DURING LEFT ATRIAL APPENDAGE CLOSURE WITH WATCHMAN FLX

Left atrial appendage (LAA) closure is an option for patient with atrial fibrillation that cannot take oral anticoagulant due to high bleeding risk. Before release of device PASS (position, anchor, size and seal) criteria must be verified. Optimal compression rate for watchman FLX device is between 10-30% according to company recommendations. The study evaluates the correlation between compression rate and leak presence after left atrial appendage closure. This is a study including patients that underwent LAA closure under transesophageal echocardiography (TEE) with at least one follow-up where complete LAA closure was assessed by TEE in our center. All TEE images were reviewed by the first author. Compression rate was calculated based on intraprocedural TEE images using the following formula: (original device size—size after deployment)/original device size*100. Patients were divided into 2 groups based on the compression rate: group 1: 10-30%; group 2: >30%. The rate of leak between groups was compared using the Chi-square test. 83 patients (mean age 77± 7 years) were included in the study. The implanted device size was 20 mm in 2 (2.4%), 24 mm in 11 (13.2%), 27 mm in 21 (25.3%), 31 mm in 32 (38.5%) and 35 mm in 17 (20.4%) patients. Based on the compression rate, patients were classified into group 1: >30% [n=11 (13.2%)] and group 2: ≤30% [n=72 (86.7%)]. Mean compression rate was 37.1% and 20.78% in group 1 and 2 respectively. At follow-up TEE, 20 (24%) patients were found to have a residual leak of <5 mm. When comparing leaks between the two groups, there was no leak in patients with > 30% compression rate whereas in the group with ≤30% there were 20 leaks (0/11 vs 20/72, p value 0.04, RR 0, 95% CI, 0-1). Devices with compression rate ≤30% were associated with significantly higher risk of residual leak.

Impact of Computational Modeling on Transcatheter Left Atrial Appendage Closure Efficiency and Outcomes

BackgroundWhen performing transcatheter left atrial appendage (LAA) closure, peridevice leaks and device-related thrombus (DRT) have been associated with worse clinical outcomes—hence, their risk should be mitigated. ObjectivesThe authors sought to assess whether use of preprocedural computational modeling impacts procedural efficiency and outcomes of transcatheter LAA closure. MethodsThe PREDICT-LAA trial (NCT04180605) is a prospective, multicenter, randomized trial in which 200 patients were 1:1 randomized to standard planning vs cardiac computed tomography (CT) simulation–based planning of LAA closure with Amplatzer Amulet. The artificial intelligence–enabled CT-based anatomical analyses and computer simulations were provided by FEops (Belgium). ResultsAll patients had a preprocedural cardiac CT, 197 patients underwent LAA closure, and 181 of these patients had a postprocedural CT scan (standard, n = 91; CT + simulation, n = 90). The composite primary endpoint, defined as contrast leakage distal of the Amulet lobe and/or presence of DRT, was observed in 41.8% in the standard group vs 28.9% in the CT + simulation group (relative risk [RR]: 0.69; 95% CI: 0.46-1.04; P = 0.08). Complete LAA closure with no residual leak and no disc retraction into the LAA was observed in 44.0% vs 61.1%, respectively (RR: 1.44; 95% CI: 1.05-1.98; P = 0.03). In addition, use of computer simulations resulted in improved procedural efficiency with use of fewer Amulet devices (103 vs 118; P < 0.001) and fewer device repositionings (104 vs 195; P < 0.001) in the CT + simulation group. ConclusionsThe PREDICT-LAA trial demonstrates the possible added value of artificial intelligence–enabled, CT-based computational modeling when planning for transcatheter LAA closure, leading to improved procedural efficiency and a trend toward better procedural outcomes.

Predictive Power for Thrombus Detection after Atrial Appendage Closure: Machine Learning vs. Classical Methods.

Device-related thrombus (DRT) after left atrial appendage (LAA) closure is infrequent but correlates with an increased risk of thromboembolism. Therefore, the search for DRT predictors is a topic of interest. In the literature, multivariable methods have been used achieving non-consistent results, and to the best of our knowledge, machine learning techniques have not been used yet for thrombus detection after LAA occlusion. Our aim is to compare both methodologies with respect to predictive power and the search for predictors of DRT. To this end, a multicenter study including 1150 patients who underwent LAA closure was analyzed. Two lines of experiments were performed: with and without resampling. Multivariate and machine learning methodologies were applied to both lines. Predictive power and the extracted predictors for all experiments were gathered. ROC curves of 0.5446 and 0.7974 were obtained for multivariate analysis and machine learning without resampling, respectively. However, the resampling experiment showed no significant difference between them (0.52 vs. 0.53 ROC AUC). A difference between the predictors selected was observed, with the multivariable methodology being more stable. These results question the validity of predictors reported in previous studies and demonstrate their disparity. Furthermore, none of the techniques analyzed is superior to the other for these data.

Left atrial appendage preservation versus closure during surgical ablation of atrial fibrillation

ObjectiveThere is limited evidence regarding the effectiveness of left atrial appendage (LAA) closure during surgical ablation of atrial fibrillation (AF) in yielding superior clinical outcomes. This study aimed to evaluate...

PO-671-07 SAFETY OF AMULET LAA OCCLUDER AND WATCHMAN DEVICE FOR LEFT ATRIAL APPENDAGE CLOSURE IN PATIENTS WITH ATRIAL FIBRILLATION

Left atrial appendage (LAA) closure is an alternative to chronic anticoagulation for stroke prevention in patients with nonvalvular atrial fibrillation. Multiple devices were used for LAA closure with Amplatzer Amulet LAA Occluder and Watchman Device being the most used in clinical practice. In August 2021, the FDA approved the use of the Amplatzer Amulet LAA Occluder. There is still a knowledge gap in in the safety profile of the Amplatzer Amulet LAA occluder device in comparison to Watchman device. The aim of this study was to assess and compare the safety profile peri-procedure and post-procedure between the Amplatzer Amulet LAA occluder and Watchman device. Patients who underwent LAA closure using Watchman or Amulet devices from July 2015 to August 2020 at the American University of Beirut Medical Center were included in the analysis. Primary endpoints included peri-operative and post procedural complications (thromboembolic events, bleeding complications, vascular access complications, pericardial effusion/tamponade, device positional complications and in-hospital death). The study included 37 patients (21 had Watchman devices, 16 had Amplatzer Amulet LAA occluder devices, 28 were men, mean age 76.57 +/- 9.3 years).Seven patients who developed post-procedural iatrogenic atrial septal defects (4 in the Watchman group vs 3 in the Amulet group, p-value= 0.982).Three patients developed pericardial effusion (1 in the Watchman vs 2 in the Amulet group, p- value = 0.394). Only one patient developed peri-device leak (1 in the Watchman group vs none in the Amulet group, p-value =0.283).One device could not be deployed (1 in the Amulet group vs none in the Watchman group, p-value= 0.191).None of the patients developed in-hospital death, cardiac tamponade, device embolism, device thrombosis, stroke/TIA, cranial bleeding, or arrhythmias after the procedure. The rate of peri-operative complications was similar between both groups.Both groups displayed low rates of adverse events in the peri-operative and post-operative period. There was no significant difference in the safety profile of Amplatzer Amulet LAA occluders and Watchman devices. There was a low incidence of peri-operative and post-operative adverse events with the implanted devices.

Surgical left atrial appendage closure: success rate and its relationship with cerebrovascular accident

Background: Several surgical procedures such as excision or exclusion are recommended for the closure of the left atrial appendage (LAA). This study was conducted with the aim to evaluate the success rate of different surgical techniques for LAA closure, their respective complications, and the rate of post-surgical cerebrovascular accident (CVA). Methods: This retrospective study included 150 consecutive patients who underwent LAA closure most commonly after mitral valve surgery within 3 to 6 months after surgery. An expert echocardiographic fellow collected the data on patients’ surgical LAA closure methods and history of CVA, types of prosthetic valves, mortality, and bleeding. Results: The failure rate for complete LAA closure was 36.7% (55 patients) in our study. The greatest success rate of complete LAA closure was seen in purse-string method (75.5%), followed by resection method (71.4%), while the lowest success rate (≈ 33.3%) was observed in ligation method. A significant relationship was observed between clots on the surface of metallic valve and postoperative CVA (P = 0.001; likelihood ratio: 32).In multivariate analysis, there was also no statistically significant relationship between partial LAA closure and the incidence of post-surgical CVA (P > 0.050). Conclusion: We observed the highest success rate of complete LAA closure in purse-string method followed by resection method. Interestingly, our results showed that despite the higher rate of residual LAA clot in cases of partial LAA closure, the occurrence of post-surgical CVA was mostly related to the presence of clots on the surface of metallic mitral prostheses rather than the presence of partial LAA closure.

Preserved Left Atrial Function Following Left Atrial Appendage Closure for Stroke Prevention.

Patients with atrial fibrillation (AF) are at high risk of thromboembolism, with most thrombi forming in the left atrial (LA) appendage. LA appendage closure is an alternative therapy to oral anticoagulation for stroke prevention in AF patients with contraindication to oral anticoagulation. LA function is critical for cardiovascular function, and recent studies suggested a direct relationship between LA function and AF recurrence. Deformation imaging characterizes and quantifies myocardial function. This study aims to investigate the impact of LA appendage closure on LA function in patients with paroxysmal AF. We studied patients with paroxysmal AF who underwent LA appendage closure in a single-center, retrospective study. Twelve patients (CHA2DS2-VASc score, 4.12 ± 1.1; age, 75.9 ± 6.9 years; 7 men and 5 women) were eligible. Echocardiography-derived LA global longitudinal strain analysis, LA diameter, and LA volume index were determined before and after a 6-month follow-up. All patients were in sinus rhythm during echocardiography. The LA global longitudinal strain was unchanged after LA appendage closure (from -18.9 ± 2.8% to -19.6 ± 2.6%; P=.66). No changes were observed for LA size (from 49.1 ± 6.1 mm to 50.5 ± 5.2 mm; P=.45) or for LA volume index (from 51.6 ± 4.6 mL/m² to 52.1 ± 4.1 mL/m²; P=.49), corroborating unaltered LA function after LA appendage closure. LA function is crucial for cardiovascular function and recurrence of AF. Our study provides evidence that LA appendage closure preserves LA function, determined by strain imaging in patients with paroxysmal AF and sinus rhythm during echocardiography.

Image fusion of integrating fluoroscopy into 3D computed tomography in guidance of left atrial appendage closure.

We evaluated the feasibility of left atrial appendage (LAA) closure guided by the image fusion of integrating fluoroscopy into 3D computed tomography (CT). A total of 117 consecutive patients who underwent LAA closure with or without the image fusion were matched (1:2). Each LAA closure step of the Image fusion group was guided by the preprocedure CT and image fusion, especially in the plan of LAA measurement and transseptal puncture. All patients were successfully implanted with a WATCHMAN closure device. Comparing the two groups, the mean number of recapture times and the number of devices per patient of the Image fusion group were significantly lower (0.4 ± 0.5 vs. 0.7 ± 0.8, P = 0.031 and 1.0 ± 0.2 vs. 1.1 ± 0.3, P = 0.027, respectively). The one-time successful deployment rate by the support of the image fusion was higher than in the control group (66.7% vs. 44.9%, P = 0.026). Each case of the Image fusion group was completely occluded with one transseptal puncture, while five of the Non-image fusion group required redo transseptal punctures. During the 45-day follow-up, both group cases presented occlusion efficiency and no major adverse cardiac events were observed. Image fusion technique integrating fluoroscopy into the 3D CT is safe and feasible which can be easily incorporated into the procedural work-flow of percutaneous LAA closure. The fusion image can play an important alternative role in the plan of LAA measurement and transseptal puncture site for improving the LAA closure procedure.

Registry of left atrial appendage closure and initial experience with intracardiac echocardiography

Abstract Introduction Percutaneous closure of the left atrial appendage (LAA) is a promising therapy in patients with atrial fibrillation with high risk for stroke and contraindication for oral anticoagulation (OAC). Intracardiac echocardiography (ICE) may make this percutaneous procedure feasible in patients in whom transesophageal echocardiography (TEE) is inadvisable. Our aim was to assess the efficacy and safety of LAA closure and the feasibility of ICE compared to TEE to guide the procedure. Methods In this cohort study of patients who underwent LAA closure between May 2010 and January 2017, clinical and imaging assessment was performed before and after the procedure. Results In 82 patients (mean age 74±8 years, 64.4% male) the contraindications for OAC were severe bleeding or anemia (65%), high bleeding risk (14%), labile INR (16%), or recurrent embolic events (5%). The procedural success rate was 96.3%. The procedure was guided by TEE or ICE, and no statistically significant differences were observed between the two techniques. During follow-up, one patient had an ischemic stroke at 12 months, two had bleeding complications at six months, and there were four non-cardiovascular deaths. Embolic and bleeding events were less frequent than expected from the observed CHA2DS2VASc (0.6% vs. 6.3%; p Conclusions In this population percutaneous LAA closure was shown to be safe and effective given the lower frequency of events than estimated by the CHA2DS2VASc and HAS-BLED scores. The clinical and imaging results of procedures guided by ICE in the left atrium were not inferior to those guided by TEE.

Registo de encerramento percutâneo do apêndice auricular esquerdo e experiência inicial com ecografia intracardíaca

IntroductionPercutaneous closure of the left atrial appendage (LAA) is a promising therapy in patients with atrial fibrillation with high risk for stroke and contraindication for oral anticoagulation (OAC). Intracardiac echocardiography (ICE) may make this percutaneous procedure feasible in patients in whom transesophageal echocardiography (TEE) is inadvisable. Our aim was to assess the efficacy and safety of LAA closure and the feasibility of ICE compared to TEE to guide the procedure. MethodsIn this cohort study of patients who underwent LAA closure between May 2010 and January 2017, clinical and imaging assessment was performed before and after the procedure. ResultsIn 82 patients (mean age 74±8 years, 64.4% male) the contraindications for OAC were severe bleeding or anemia (65%), high bleeding risk (14%), labile INR (16%), or recurrent embolic events (5%). The procedural success rate was 96.3%. The procedure was guided by TEE or ICE, and no statistically significant differences were observed between the two techniques. During follow‐up, one patient had an ischemic stroke at 12 months, two had bleeding complications at six months, and there were four non‐cardiovascular deaths. Embolic and bleeding events were less frequent than expected from the observed CHA2DS2VASc (0.6% vs. 6.3%; p<0.001) and HAS‐BLED (1.2% vs. 4.1%; p<0.001) risk scores. ConclusionsIn this population percutaneous LAA closure was shown to be safe and effective given the lower frequency of events than estimated by the CHA2DS2VASc and HAS‐BLED scores. The clinical and imaging results of procedures guided by ICE in the left atrium were not inferior to those guided by TEE.

Device-Related Thrombosis After Percutaneous Left Atrial Appendage Occlusion for Atrial Fibrillation

BackgroundTranscatheter left atrial appendage (LAA) occlusion is an alternative strategy for stroke prevention in patients with atrial fibrillation (AF). ObjectivesThis study sought to determine the incidence, predictors, and prognosis of thrombus formation on devices in patients with AF who were treated with LAA closure. MethodsThe study retrospectively analyzed data from patients treated with 2 LAA closure devices seen in 8 centers in France from February 2012 to January 2017. ResultsA total of 469 consecutive patients with AF underwent LAA closure (272 Watchman devices [Atritech, Boston Scientific, Natick, Massachusetts] and 197 Amplatzer devices [St. Jude Medical, Minneapolis, Minnesota]). Mean follow-up was 13 ± 13 months, during which 339 (72.3%) patients underwent LAA imaging at least once. There were 98 major adverse events (26 thrombi on devices, 19 ischemic strokes, 2 transient ischemic attacks, 18 major hemorrhages, 33 deaths) recorded in 89 patients. The incidence of device-related thrombus in patients with LAA imaging was 7.2% per year. Older age (hazard ratio [HR]: 1.07 per 1-year increase; 95% confidence interval [CI]: 1.01 to 1.14; p = 0.02) and history of stroke (HR: 3.68; 95% CI: 1.17 to 11.62; p = 0.03) were predictors of thrombus formation on the devices, whereas dual antiplatelet therapy (HR: 0.10; 95% CI: 0.01 to 0.76; p = 0.03) and oral anticoagulation at discharge (HR: 0.26; 95% CI: 0.09 to 0.77; p = 0.02) were protective factors. Thrombus on the device (HR: 4.39; 95% CI: 1.05 to 18.43; p = 0.04) and vascular disease (HR: 5.03; 95% CI: 1.39 to 18.23; p = 0.01) were independent predictors of ischemic strokes and transient ischemic attacks during follow-up. ConclusionsThrombus formation on the device is not uncommon in patients with AF who are treated by LAA closure. Such events are strongly associated with a higher risk of ischemic stroke during follow-up. (REgistry on Real-Life EXperience With Left Atrial Appendage Occlusion [RELEXAO]; NCT03279406)

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.

3D printing for sizing left atrial appendage closure device: head-to-head comparison with computed tomography and transoesophageal echocardiography.

Device sizing for LAA closure using transoesophageal echocardiography (TEE) can be challenging due to complex LAA anatomy. We investigated whether the use of 3D-printed left atrial appendage (LAA) models based on preprocedural computed tomography (CT) permits accurate device sizing. Twenty-two (22) patients (73±8 years, 55% male) with atrial fibrillation requiring anticoagulation at high bleeding risk underwent LAA closure (WATCHMAN device). Preprocedurally, LAA was sized by TEE and third-generation dual-source CT. Based on CT, 3D printing models of LAA anatomy were created for simulation of device implantation. Device compression was assessed in a CT scan of the 3D model with the implanted device. Implantation was successful in all patients. Mean LAA ostium diameter based on TEE was 22±4 mm and based on CT 25±3 mm (p=0.014). Predicted device size based on simulated implantation in the 3D model was equal to the device finally implanted in 21/22 patients (95%). TEE would have undersized the device in 10/22 patients (45%). Device compression determined in the 3D-CT model corresponded closely with compression upon implantation (16±3% vs. 18±5%, r=0.622, p=0.003). Patient-specific CT-based 3D printing models may assist device selection and prediction of device compression in the context of interventional LAA closure.

Short-term safety and efficacy of left atrial appendage closure with the WATCHMAN device in patients with small left atrial appendage ostia.

Left atrial appendage (LAA) closure with the WATCHMAN device, according to FDA labelling, is recommended in patients with a maximal LAA ostial width between 17 and 31mm. The safety and efficacy of LAA closure in patients with a maximal LAA ostial width<17mm has not been evaluated. The goal of this study was to determine the acute and short-term safety and efficacy of LAA closure with the WATCHMAN device in patients with a maximal LAA ostial width<17mm. Thirty-two consecutive patients with a maximal LAA ostial width<17mm as determined by a screening transesophageal echocardiogram (TEE) underwent LAA closure with the WATCHMAN device between March 2015 and November 2016 at five medical centers, and were included in this study. Mean age, body mass index (BMI), and CHA2 DS2 -VASC score were 70.8 ± 8.6 years, 29.3 ± 6.5kg/m2 , and 3.9 ±1.2, respectively. At the screening TEE, mean maximal LAA ostial width and depth were 15.6 ± 0.6mm (range 14-16) and 23.2 ± 4.5mm (range 13-31), respectively. Successful LAA closure with the WATCHMAN device was achieved in 31 of 32 patients (97%), with no major complications. TEE performed 45 days after LAA closure demonstrated no peridevice leak>5mm and no device related thrombi. Warfarin was discontinued in all 31 patients 45 days after LAA closure. LAA closure with the WATCHMAN device can be successfully and safely achieved in patients with a maximal LAA ostial width<17mm.