The ABC of sealing following left atrial appendage closure.

PO-03-192 INTRA-DEVICE LEAKS ON POST LEFT ATRIAL APPENDAGE OCCLUDER FOLLOW UP TOMOGRAPHIC IMAGING – TRUE LEAK OR MERE INCOMPLETE ENDOTHELIALIZATION

Peridevice Leak Following Amplatzer Left Atrial Appendage Occlusion: Cardiac Computed Tomography Classification and Clinical Outcomes.

0095: Evaluation of peri device leaks after percutaneous left atrial appendage closure using cardiac computed tomography

P ercutaneous left atrial appendage (LAA) closure (LAAC) prevents thromboembolisms in patients with atrial fibrillation. However, residual LAA patency after LAAC has been associated with higher thromboembolic risk, especially when detected remotely after the procedure. 1 Residual leaks are typically assessed by transesophageal echocardiography or cardiac computed tomography angiography (CCTA), and the latter imaging modality provides a comprehensive operator-independent assessment and higher sensitivity compared with transesophageal echocardiography. 2 The SWISS-APERO trial (Comparison of Amulet Versus Watchman/FLX Device in Patients Undergoing Left Atrial Appendage Closure; URL: https://clinicaltrials.gov; Unique identifier: NCT03399851) is the first random-ized comparison between Watchman FLX (Boston Scientific) and Amplatzer Amulet (Abbott), which are the 2 most frequently used devices for LAAC worldwide. 3,4 Patients with nonvalvular atrial fibrillation and clinically indicated LAAC were eligible if they provided written informed consent and had a CHA 2 DS 2-VASc score of ≥2 and either HAS-BLED score of ≥3 or presence of high-bleeding-risk features. 3 The key exclusion criteria included the presence of LAA thrombus or LAA morphology not suitable for both study devices at trans-esophageal echocardiography. All patients randomized to Watchman before October 2019 received Watchman 2.5; Watchman FLX was used exclusively thereafter. Postimplantation treatment was left to discretion of the treating physician. At 13 months (395±30 days), patients underwent an onsite clinical visit and CCTA. The CCTA images and clinical events were centrally and blindly assessed. LAA was defined as patent appendage (PA) if LAA density was ≥100 Hounsfield unit or ≥25% of that of the left atrium. 3,4 In patients with PA, the presence of visible leaks was adjudicated as intradevice leak, peridevice leak, or mixed leak if contrast medium was visible along the entire length or part of the length of the device or as PAs with no visible leak if none of the above was detected. Device-related thrombus was defined as homogeneous hypoattenu-ated thickening on the atrial surface of the device and centrally adjudicated as definitive or possible device-related thrombus. 3 The trial was an investigator-initiated trial, partially supported by a research grant from Abbott (St. Jude Medical/Abbott, North Plymouth, MN). The trial protocol was approved by the institutional review boards, and all patients provided informed consent before enrollment. The imaging end points were analyzed with the χ 2 test, and risk ratios (RRs) with 95% CIs are reported. The clinical end points were analyzed with Cox proportional hazards model, and hazard ratios with 95% CIs are reported. Data were analyzed according to the intention-to-treat

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

Background Peri-device leaks (PDLs) after left atrial appendage closure (LAAC) portend a higher residual risk of thromboembolism in patients with Atrial Fibrillation (AF). Therefore, closure of PDLs has evolved as a procedural strategy to mitigate this residual thromboembolic risk. Objective To present our procedural experience and outcome data in patients who underwent PDL-closure after prior LAAC. Methods We performed a retrospective review of patients with follow-up imaging data (either transesophageal echocardiograms or Cardiac CT scans) performed at ∼1 year after LAAC between the time-period 5/2015 – 10/2022 to assess PDLs. Results We included a total of 532 patients with follow-up imaging data. At a mean follow up of 696±359 days post-LAAC, 63 of 532 (11.8%) patients underwent PDL closure. These PDL closure cohort was age 73.1±9.5 years, 41 of 62 (65%) had paroxysmal AF, and the CHA2DS2-Vasc was 3.7±1.5. In 42 of 62 (67.7%) patients, the initial LAAC device was Watchman, and in 21 (33.8%) patients, it was Watchman-FLX. Of the PDL closure cohort, 8 of 62 (12.9%) had a post-LAAC thromboembolic event (transient ischemic attack [TIA], stroke or systemic embolism). The PDL size was 3.8±2.0 mm. PDL closure was performed using endovascular coils alone in 23 (37.1%), plugs (Amplatzer devices, Abbott) alone in 18 (29%), and combinations of both in 13 (19.4%) patients. In 8 (14.5%) patients, radiofrequency ablation was used in concert with both coils and plugs (Figure). There was only 1 complication (pericardial effusion drained percutaneously) during the PDL closure procedure. During follow-up post-PDL closure, no patient sustained a stroke and only 1 patient had a TIA (Table). Conclusions Our data indicate that PDL closure after LAAC is feasible and safe, with a low risk of procedural complications. Such a strategy can be used in a subset of high-risk patients with PDL after LAAC who are at an elevated residual risk of thromboembolism.Table summarizing procedural strategies

PO-03-162 INCIDENCE AND PREDICTORS OF PERI-DEVICE LEAKS IN A REAL-WORLD SETTING AFTER LEFT ATRIAL APPENDAGE CLOSURE WITH WATCHMAN DEVICE

Diagnosing Endocarditis: Get the Picture?!

Device surveillance after left atrial appendage (LAA) closure (LAAC) is important to assess device positioning, peri-device leak (PDL) and device-related thrombus (DRT). There are limited data on the role of cardiac CT angiography (CCTA) after LAAC. We therefore sought to compare CCTA to transoesophageal echocardiography (TEE) in patients who successfully underwent LAAC. We report our consecutive series of non-valvular atrial fibrillation patients who underwent LAAC and had CCTA and TEE post LAAC. Prospective cardiac-gated CCTA was performed with the Toshiba 320-detector or Siemens second-generation 128-slice dual-source scanner, and post-processing was performed with IMPAX 3D reformats. Glomerular filtration rate <30 mL/min/1.73 m² was an exclusion for CCTA. Device positioning, PDL or fabric leak, ratio of left atrial (LA) to LAA linear attenuation coefficient, and DRT were analysed. One hundred and two patients underwent LAAC (79 WATCHMAN, 17 Amulet, 6 ACP). Mean age was 76.4±7.5 years, CHADS2 score 3.0±1.3, and CHADS-VASc score 4.6±1.6. CCTA was performed at a mean of 105.2±54.8 days, and TEE at a mean of 124.9±100.3 days post LAAC. LAA patency was observed in 52/100 (52%), with 45 (86.5%) via PDL and seven (13.5%) through fabric leak. Linear attenuation coefficient <100 HU and LA:LAA ratio <0.25 were seen in occluded devices. PDL was only observed in 35/102 (34.3%) on TEE. Mean device compression was greater with sealed devices (11.3±4.3% versus 8.2±4.0%, p<0.001). There was only one DRT, which was observed on both TEE and CCTA. CCTA is a suitable alternative to TEE for device surveillance post LAAC. CCTA was more sensitive than TEE for assessing PDL and can delineate the cause of residual LAA contrast patency.

PO-01-083 PERCUTANEOUS CLOSURE OF PERI-DEVICE LEAK FOLLOWING LEFT ATRIAL APPENDAGE CLOSURE USING AN AMPLATZER DUCT OCCLUDER

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.

Transesophageal echocardiography (TEE) has been the preferred imaging modality to help guide left atrial appendage closure. Newer technologies such as the Nuvision 4D Intracardiac echocardiography (ICE) catheter allow for real-time 3D imaging of cardiac anatomy. There are no direct comparison studies for procedural imaging between TEE and 4D ICE. To evaluate the performance and safety of left atrial appendage (LAA) closure procedures with the Watchman FLX and Amulet, guided by the Nuvision 4D ICE Catheter. This retrospective observational analysis was conducted on institutional LAAO National Cardiovascular Data Registry from January 2022 to March 2023. Patients had undergone LAA closure procedures with the Watchman FLX or Amulet device guided by TEE or a 4D ICE Catheter. The primary outcome evaluated was successful LAAO device placement. A total of 121 patients underwent LAAO device placement with 46 (38.0%) patients guided by 4D ICE during LAAO implantation. The 4D ICE group had a shorter procedural time compared with TEE guidance. Post procedural 45-day TEE post implant was also comparable for both groups with no patients in either group having incomplete closure of the left atrial appendage and peri-device leak > 5 mm. No device related complications (device related access, stroke, or pericardial effusion) occurred in either group at follow-up. There was no significant difference in device implant success or post procedural outcomes at 45 days in either the TEE or 4D ICE group. However, there was a noticeable improvement in procedural time with the 4D ICE catheter.

Background: Percutaneous left atrial appendage closure (LAAC) requires accurate pre- and intraprocedural measurements, and multimodality imaging is an essential tool for guiding the procedure. Two-dimensional (2D TOE) and three-dimensional (3D TOE) transoesophageal echocardiography, cardiac computed tomography (CCT), and conventional cardiac angiography (CCA) are commonly used to evaluate left atrial appendage (LAA) size. However, standardized approaches in measurement methods by different imaging modalities are lacking. The aims of the study were to evaluate the LAA dimension and morphology in patients undergoing LAAC and to compare data obtained by different imaging modalities: 2D and 3D TOE, CCT, and CCA. Methods: A total of 200 patients (mean age 70 ± 8 years, 128 males) were examined by different imaging techniques (161 2D TOE, 103 3D TOE, 98 CCT, and 200 CCA). Patients underwent preoperative CCT and intraoperative 2D and 3D TOE and CCA. Results: A significant correlation was found among all measurements obtained by different modalities. In particular, 3D TOE and CCT measurements were highly correlated with an excellent agreement for the landing zone (LZ) dimensions (LZ diameter: r = 0.87; LAA depth: r = 0.91, p < 0.001). Conclusions: Head-to-head comparison among imaging techniques (2D and 3D TOE, CCT, and CCA) showed a good correlation among LZ diameter measurements obtained by different imaging modalities, which is a parameter of paramount importance for the choice of the LAAC device size. LZ diameters and area by 3D TOE had the best correlation with CCT.

ObjectivesTo explore the value of detecting the peri‐device leak (PDL) and device endothelialization after left atrial appendage closure (LAAC) by cardiac computed tomography (CT) in patients with atrial fibrillation (AF), who underwent Watchman LAAC combined with radiofrequency ablation of atrial fibrillation (AFCA).MethodsPatients with symptomatic drug‐refractory atrial fibrillation at high risk of stroke (CHA2DS2‐VASc Score ≥ 2), who underwent Watchman LAAC combined with AFCA in our center from March 2017 to December 2018 were enrolled. Maximum diameter of LAA orifice was determined by preoperative CCTA. A standardized view of Watchman device was obtained by postoperative CCTA multiplannar reconstruction to evaluate the PDL and device endothelialization.ResultsApproximately 84 patients post successful LAAC and AFCA were enrolled in this study. The satisfactory LAA occlusion rate was 100%. There was no death, bleeding, stroke, and device‐related thrombus (DRT) events. At 6‐month postprocedure, CCTA images evidenced complete endothelialization in 44 patients (no contrast enhancement in LAA); contrast enhancement in LAA and visible PDL in 33 patients; contrast enhancement in LAA but without PDL in seven patients (incomplete device endothelialization). Maximum diameter of LAA orifice could independently predict the occurrence of PDL (odds ratio, 1.31; 95% confidence interval, 1.11–1.55; p = .002), sensitivity was 69.7% and specificity was 80.4% with the cutoff value of maximum diameter of LAA orifice more than 28.2 mm on predicting PDL.ConclusionsCCTA is feasible to evaluate PDL and device endothelialization after LAAC. The maximum diameter of LAA orifice derived from CT can independently predict the occurrence of post‐LAAC PDL.

Percutaneous transcatheter left atrial appendage (LAA) closure (LAAC) is an effective approach for preventing ischemic stroke in nonvalvular atrial fibrillation patients. Intracardiac echocardiography (ICE), a new imaging modality, is a promising strategy for guiding LAAC. This review highlights the various strategies for ICE-guided-LAAC as an option for clinical policy. A comprehensive literature search was conducted of PubMed, ScienceDirect, Ovid Web of Science, SpringerLink, and other notable databases to identify recent peer-reviewed clinical trials, reviews, and research articles related to ICE and its application in the guidance of LAAC. Various methods are used to evaluate the spatial structure and dimensions of the LAA. The main techniques for guiding LAAC are transesophageal echocardiography (TEE), cardiac computed tomography (CTA), and ICE. Among these techniques, the advantages of ICE typically include (1) multiangle and real-time assessment of intracardiac structure, (2) a reduction in procedural fluoroscopy, (3) reduced operation time and improved workflow in the catheterization laboratory, and (4) the avoidance of general anesthesia and the early detection of complications. ICE is a promising strategy for the guidance of LAAC. Among the most advanced and recent technological innovations in cardiovascular imaging in general and volume imaging in particular, ICE offers greater efficacy and safety.