Left Atrial Appendage Closure Device Research Articles

Reactive atrial-based anti-tachycardia pacing algorithm in cardiovascular implantable electronic devices is safe and feasible without increase in thromboembolic events in patients with a left atrial appendage closure device

BackgroundReactive atrial-based anti-tachycardia pacing (rATP) in CIED (cardiovascular implantable electronic devices) is effective in atrial fibrillation (AF) suppression. Uninterrupted systemic anticoagulation is recommended when this algorithm is activated to avoid stroke, however, the use of a rATP algorithm in patients with a left atrial appendage (LAA) closure device has not been studied. We assessed the safety and feasibility of rATP algorithm to suppress AF in patients with a LAA closure device over an extended period.MethodsData from 55 consecutive patients who underwent a Watchman® implant at a tertiary care hospital between September 1, 2015, and January 30, 2020, who also had an in situ Medtronic® CIED (45 with and 10 without rATP capability) were retrospectively reviewed.ResultsThe 55-patient cohort was 60% male, 77 ± 8 years old, CHA2DS2-VASc score 5 (4–6), HAS-BLED score 3 (3–4), LVEF 53 ± 14%, LA size 4.4 ± 0.7 cm and ventricular pacing burden of 73 (1.4–98.3)%. The CIEDs (20 ICDs and 35 pacemakers) antedated Watchman® implants by 915 ± 725 days. Post-implant, all patients discontinued anticoagulation. Twenty patients in the rhythm-control group with active rATP algorithm displayed no increase in yearly AF burden and were less likely to develop permanent/long-standing persistent AF (p = 0.002) when compared to 35 patients in the rate-control group with CIEDs inactive/incapable of rATP over a ≤ 5-year follow-up. The longest AF episode in the rhythm-control group lasted 204 (19–2520) h. There was no increase in stroke/thromboembolism and a significant reduction in major bleeding noted over ≤ 5 years pre- versus post-implant in the whole cohort (p = 0.005).ConclusionrATP algorithm use is safe and feasible in patients with a Watchman® device. Patients should be forewarned of a surge in post-Watchman® implant AF burden.

Characterization of Left Atrial Appendage Closure Device Protrusion and Implications for Transcatheter Mitral Valve Replacement

Characterization of Left Atrial Appendage Closure Device Protrusion and Implications for Transcatheter Mitral Valve Replacement

Transcatheter mitral valve leak closure with left atrial appendage closure device: kill two birds with one stone.

Transcatheter mitral valve leak closure with left atrial appendage closure device: kill two birds with one stone.

Catheter based left atrial appendage closure in-hospital outcomes in Germany from 2016 to 2020

BackgroundNew and refined catheter based left atrial appendage (LAA) closure devices have been introduced in the past decade. The procedure can be performed using either an endocardial occlusion device or an epicardial loop stitch. We aimed to analyzed recent procedural safety.MethodsCatheter based LAA closures were identified in a complete nationwide German dataset via ICD and OPS codes from 2016 to 2020.ResultsFrom 2016 to 2020, 28,039 endocardial and 213 epicardial occlusions were performed. Numbers of endocardial procedures increased from 5259 in 2016 to 5917 in 2020 (p = 0.020) in 387 centers with shifting of patients’ characteristics towards older age (β = 0.29, p < 0.001), more heart failure (β = 1.01, p < 0.001) and renal disease (β = 0.67, p = 0.001) and without a significant trend for in-hospital safety except more bleeding (β = 0.12, p = 0.05). In-hospital major adverse cardiac and cerebrovascular events (MACCE) or pericardial puncture were independent on center procedure numbers.The loop stitch procedure was performed in 15 centers. Patients were younger (76.17 ± 8.16 vs. 73.16 ± 8.99, p < 0.001) and had a lower comorbidity index (2.29 ± 1.93 vs. 1.92 ± 1.64, p = 0.005). Adjusted risk difference for pericardial effusion (8.04%; 95% CI 3.01–13.08%; p = 0.002) and pericardial puncture (6.60%; 95% CI 3.85–9.35%; p < 0.001) was higher for the loop stitch procedure, while risk of bleeding (− 1.85%; 95% CI − 3.01 to − 0.69%; p = 0.002), intracerebral bleeding (− 0.37%; 95% CI − 0.59 to − 0.15%; p = 0.001) and shock (− 1.41%; 95% CI − 2.44 to − 0.39%; p = 0.007) was lower. No significant difference was observed for in-hospital MACCE.ConclusionsEndocardial occlusion was the major catheter based LAA closure procedure in Germany without improvements in in-hospital safety from 2016 to 2020. In-hospital MACCE was independent on endocardial LAAC center volumes. Conclusions on the comparison between the two procedure types must be made cautious as the LAA loop stitch occlusion was utilized limited in a minor number of centers.Graphical abstractCatheter based left atrial appendage closure in-hospital outcomes in Germany from 2016 to 2020

The Emerging Role of Intracardiac Echocardiography (ICE) in Left Atrial Appendage Closure (LAAC).

Intracardiac echocardiography (ICE) has emerged as a powerful imaging tool to guide percutaneous left atrial appendage closure (LAAC). Herein, we review an imaging protocol for ICE-guided LAAC and discuss the evidence for its use. Standardized imaging protocols have been proposed but have not been fully validated. ICE imaging yields similar procedural and clinical outcomes when compared to transesophageal echocardiography (TEE) to guide LAAC. Despite benefits of avoiding general anesthesia, TEE, and multiple physicians for LAAC procedures, ICE imaging remains under-utilized. Novel ICE catheters with 3D imaging capabilities may improve accuracy and efficiency of LAAC device implantation. ICE guidance is feasible, safe, and effective for LAAC. As the field evolves, further studies will be necessary to assess this technological advancement in imaging guidance.

Novel streamlined technique for left atrial appendage closure using a radiofrequency wire-based large access system.

Transseptal puncture (TSP) to allow for large delivery sheath left atrial (LA) access remains a challenging aspect of LA appendage closure (LAAC) in patients with prior history of TSP, thick or lipomatous septum, atrial septal aneurysms, or other complex cardiac anatomies. This study investigates the use of the VersaCross large access (VLA) system (Baylis Medical/Boston Scientific) to improve procedural efficiency of LAAC compared to the standard needle workflow. Fifty LAAC procedures using WATCHMAN FLX between November 2021 and September 2022 were retrospectively analyzed comparing the VLA workflow (n = 25) to the standard needle workflow (n = 25). Study primary endpoint was time to procedural efficiency, and secondary endpoints included TSP time, acute LAAC success, fluoroscopy use, device recaptures, and periprocedural complications. Acute LAAC was successfully completed in all cases with no intraprocedural complications. TSP time was faster, but not significant, using the VLA workflow compared to the standard RF needle workflow (2.6 ± 1.1 min vs. 3.0 ± 1.8 min, p = 0.38). Time to WATCHMAN sheath in LA from TSP was 27% faster (1.5 ± 0.8 min vs. 2.1 ± 0.9 min; p = 0.03), and time to WATCHMAN release from TSP was 19% faster (10.5. ± 2.5 min vs. 13.0 ± 3.7 min; p = 0.01) with the VLA workflow. Overall procedure time was 15% faster (30.4 ± 5.1 min vs. 36.0 ± 6.6 min; p = 0.003) using VLA. Fluoroscopy time was 25% lower (4.0 ± 2.2 min vs. 5.5 ± 2.3 min; p = 0.003) and fluoroscopy dose was 60% lower (97.0 ± 91.7 mGy vs. 241.8 ± 240.6 mGy; p = 0.01) and more consistent [F-test, p ˂ 0.0001] using the VLA workflow compared to the needle workflow. The VLA system streamlines LAAC procedures, improving LAAC efficiency and reducing fluoroscopy use by allowing for de novo dilation of the septum for large-bore delivery sheaths, and reducing device exchanges and delivery sheath manipulation.

Left Atrial Appendage Occlusion Strengths and Weaknesses of the Lobe-Only Occluder Concept in Theory and in Practice

Left atrial appendage closure aims to eliminate the stasis component of Virchow triad by eliminating a cul-de-sac that favors thrombosis, particularly when atrial contractility becomes inefficient, such as in atrial fibrillation. Left atrial appendage closure devices have a common objective of sealing the appendage completely, with device stability and avoidance of device thrombosis. Two main device designs have been used to perform left atrial appendage closure: those that use a pacifier design (lobe+disk) and those that use a plug (single lobe) design. This review highlights the potential features and benefits of the single-lobe devices.

MT45 Cost-Effectiveness Analysis of Left Atrial Appendage Closure (LAAC) Device Vesus Warfarin and New Oral Anticoagulants (NOACS) in Patients with Atrial Fibrillation (AF) - Large Brazilian Healthcare Payer Perspective

Atrial fibrillation (AF) is associated with increasing risk for stroke. Strokes are related to a large economic burden such as increased health expenditures, high and prolonged rates of hospitalization. Left atrial appendage closure (LAAC) emerged as viable treatment alternative for stroke risk reduction. The objective of the study was to evaluate the cost-effectiveness of LAAC with WATCHMAN device in the perspective of a large Brazilian healthcare payer with more than 18 million patients.

Intracardiac echocardiographic imaging with a cartosound module for guidance of left atrial appendage closure: a comparative study with transesophageal echocardiographic imaging.

In most clinical trials, intracardiac echocardiography (ICE) has provided fewer views than the four standard views provided by transesophageal echocardiography (TEE) when assessing left atrial appendage closure (LAAC) devices. This study aimed to determine if ICE guided by the CartoSound system achieve adequate high-quality views and similar clinical outcomes as TEE during LAAC. This study prospectively enrolled 202 patients who underwent LAAC using either ICE (n = 69), TEE (n = 121), or a combination of ICE and TEE (n = 12) as the procedural imaging under local anesthesia. A novel multi-angled "FLAVOR" approach was used for assessment in the ICE group. ICE allowed visualization of the implanted devices in all patients at all proposed angles with long-axis views while two-dimensional (2D) TEE showed short-axis views in 1 or 2 angles in 24.2% of cases, which was more prevalent when the pulmonary ridge was covered by the occluder. In the combined ICE-TEE cohort, 2D-TEE failed to detect peri-device leak in 1 patient. The complication rates were similar between the ICE and TEE groups. Shorter fluoroscopy time, lower radiation dose and contrast usage were founded in the ICE group. At first TEE follow-up, the rate and degree of peri-device leak were similar between the ICE and TEE groups. A systematic ICE protocol using a CartoSound module to guide LAAC was reliable for comprehensive long-axis imaging assessment compared with 2D/3D TEE under local anesthesia with a shorter fluoroscopy time, lower radiation dose, and less use of contrast.

Transcatheter Left Atrial Appendage Closure: Devices Available, Pitfalls, Advantages, and Future Directions.

Transcatheter left atrial appendage closure has emerged as a non-pharmacological alternative to long-term anticoagulation for stroke prevention in appropriately selected patients with AF. In this concise review, the Food and Drug Administration-approved and some other left atrial appendage closure devices that are under investigation are discussed. Currently, Watchman Flx and Amplatzer Amulet are the only two devices that have been approved for commercial use by the Food and Drug Administration. A brief overview of device designs, clinical data on efficacy and safety, major limitations of left atrial appendage closure devices, and perspectives on future direction are provided. The current generation of devices is effective; however, efforts should continue on innovations and refinement of device technology.

Enhanced Thromboresistance and Endothelialization of a Novel Fluoropolymer-Coated Left Atrial Appendage Closure Device

BackgroundDevice-related thrombus (DRT) after left atrial appendage closure (LAAC) procedures is a rare but potentially serious event. Thrombogenicity and delayed endothelialization play a role in the development of DRT. Fluorinated polymers are known to have thromboresistant properties that may favorably modulate the healing response to an LAAC device. ObjectivesThe goal of this study was to compare the thrombogenicity and endothelial coverage (EC) after LAAC between the conventional uncoated WATCHMAN FLX (WM) and a novel fluoropolymer-coated WATCHMAN FLX (FP-WM). MethodsCanines were randomized for implantation with WM or FP-WM devices and given no postimplant antithrombotic/antiplatelet agents. The presence of DRT was monitored by using transesophageal echocardiography and verified histologically. The biochemical mechanisms associated with coating were assessed by using flow loop experiments to quantify albumin adsorption, platelet adhesion, and porcine implants to quantify EC and the expression of markers of endothelial maturation (ie, vascular endothelial-cadherin/p120-catenin). ResultsCanines implanted with FP-WM exhibited significantly less DRT at 45 days than those implanted with WM (0% vs 50%; P < 0.05). In vitro experiments showed significantly greater albumin adsorption (52.8 [IQR: 41.0-58.3] mm2 vs 20.6 [IQR: 17.2-26.6] mm2; P = 0.03) and significantly less platelet adhesion (44.7% [IQR: 27.2%-60.2%] vs 60.9% [IQR: 39.9%-70.1%]; P < 0.01) on FP-WM. Porcine implants showed significantly greater EC by scanning electron microscopy (87.7% [IQR: 83.4%-92.3%] vs 68.2% [IQR: 47.6%-72.8%]; P = 0.03), and higher vascular endothelial-cadherin/p120-catenin expression after 3 months on FP-WM compared with WM. ConclusionsThe FP-WM device showed significantly less thrombus and reduced inflammation in a challenging canine model. Mechanistic studies indicated that the fluoropolymer-coated device binds more albumin, leading to reduced platelet binding, less inflammation, and greater EC.

PO-03-184 ASSESSMENT OF PRICE VARIATION IN PERCUTANEOUS LEFT ATRIAL APPENDAGE CLOSURE DEVICE PROCEDURES AT US HOSPITALS

Since their approval in the US in 2015, left atrial appendage closure (LAAC) devices have served as an alternative to oral anticoagulation in atrial fibrillation (AF) patients at increased risk of bleeding. However, few studies have explored the commercial cost footprint of LAAC procedures, despite the 2021 Hospital Price Transparency Final Rule mandating US hospitals publish their insurer-negotiated prices. This study sought to characterize and identify factors contributing to variation in LAAC procedure prices across the US. We queried a commercial database containing hospital-disclosed prices to characterize variation in LAAC procedure prices within and across US hospitals. We then linked this price data to hospital characteristics using Medicare Facility IDs. Univariate analysis was conducted to compare commercial prices across multiple factors. In total, 683 hospitals reported commercial prices for LAAC procedures. Among reporting hospitals, median prices were greater at major investor-owned vs. non-major investor-owned facilities ($10,991 vs. $7,227, p<0.01) and for-profit centers vs. not-for-profit and government centers ($10,991 vs. $7,417 vs. $5,051, p<0.01). Prices were also greater at non-teaching hospitals compared to minor and major teaching hospitals (p<0.01). The Pacific region exhibited the highest median price ($18,652), while the Middle Atlantic exhibited the lowest median price ($5191). There was no association between price and CMS hospital-wide mortality (p=0.21) or all-cause readmissions (p=0.29). Patient hospital ratings were correlated with price (p<0.01) but not CMS overall hospital ratings (p=0.62). Commercial and self-pay prices were 2.30- and 2.61-times higher than the Medicare price. Within hospitals, the 90th percentile payer-negotiated rate was 2.0 (IQR 1.00-4.06) times the 10th percentile rate (within-center ratio). Across hospitals within the same hospital referral region (HRR), the median price at the 90th percentile hospital was 1.54 (IQR 1.00-2.63) times that at the 10th percentile hospital (between-center ratio). Prices for LAAC procedures varied widely, with commercial and self-pay rates over double the Medicare price. Within-center variation in price was higher than between-center variation. Non-teaching, investor-owned, and for-profit hospitals had higher prices; however, there was no association between prices and hospital-wide mortality or readmission rates.Tabled 1Univariate Analysis of Factors Associated with Left Atrial Appendage Closure Device Procedures Commercial PriceCategorical Values (% Reporting)# ofHospitals (%)Median Price ($)Interquartile Range ($)P-ValueRegion (93.6)<0.01 New England (CT, MA, ME, NH, RI, VT)Middle Atlantic (NJ, NY, PA)South Atlantic (DC, DE, MD, VA, WV, C, SC, GA, FL))East North Central (OH, IN, IL, MI, WI)East South Central (KY, TN, AL, MS)West North Central (MN, IA, MO, ND, SD, NE, KS)West South Central (AR, LA, OK, TX)Mountain (MT, ID, WY, CO, NM, AZ, UT, NV)Pacific (WA, OR, CA, AK, HI)26 (4.1)59 (9.2)157 (24.6)119 (18.6)57 (8.9)78 (12.2)107 (16.7)26 (4.1)10 (1.6)90915191104657682113425900719911150186524865-125783839-94483652-145313562-113323005-152592780-124784030-114763094-122562891-26874Hospital Type (87.8)<0.01 For-ProfitNot-For-ProfitGovernment154 (25.7)407 (67.8)39 (6.5)10991741750516853-152603077-124772731-14581Major Investor Owned (96.8)<0.01 Major Investor OwnedNot Major Investor Owned173 (26.2)488 (73.8)1099172276997-152603050-12344Teaching Status (93.6)<0.01 Major TeachingMinor TeachingNon-Teaching84 (13.1)332 (52.0)223 (34.9)56488012106162475-91313340-123443840-15260Urban/Rural (100)0.06 UrbanRural620 (90.8)63 (9.2)823488373428-129183634-13784Disproportionate Share Hospital (82.3)0.63 Disproportionate Share Hospital (DSH)Sole Community Hospital (not DSH-eligible)Not DSH474 (84.3)14 (2.5)74 (13.2)81681073987693510-129885052-128633241-14189CMS Hospital-Wide Readmission Rate (82.6)0.26 Above National AverageSame as National AverageBelow National Average227 (40.2)80 (14.2)257 (45.6)8633863286493340-133264079-142673840-12579CMS Hospital-Wide Mortality (80.7)0.25 Above National AverageSame as National AverageBelow National Average99 (18.0)375 (68.1)77 (14.0)8819823789043486-119703544-132163473-15159HCAHPS Patient Overall Hospital Rating (81.1)<0.01 1234517 (3.1)96 (17.3)211 (38.1)209 (37.7)21 (3.8)10991875869649044136316295-205573635-128202856-112883844-146829078-18372CMS Overall Hospital Rating (83.1)0.62 1234526 (4.6)92 (16.2)160 (28.2)186 (32.7)104 (18.3)922490048620761886934492-120864918-126313632-130232864-132513803-13693Comparisons were done via the Kruskal-Wallis test. Open table in a new tab

PO-03-237 PERCUTANEOUS LEFT ATRIAL APPENDAGE OCCLUSION AND PERIPROCEDURAL OUTCOMES TREND IN THE UNITED STATES: AN INSIGHT FROM NATIONWIDE READMISSION DATABASE 2016-2019

The watchman device is the first percutaneous left atrial appendage closure device (pLAAC) indicated in patients with non-valvular AF who cannot tolerate anticoagulation. Our study aims to assess the national trend of utilization of percutaneous left atrial appendage closure device (pLAAC) in atrial fibrillation (AF) patients and determine risk factors and predictors associated with periprocedural morbidity and mortality. Using the National Readmission Database (NRD) database between January 2016 to December 2019, patients with AF who underwent pLAAC evaluated for complications and mortality. Logistic/multivariate regression and Cox regression were used. A total of 54,903 procedures were identified from 2016-2019, mean age 75.91± 7.74, and 76.34 ± 7.42 for the years 2016 and 2019 respectively, 58.23% were male. The total volume of procedures across the board increased consistently each year being 4671 in 2016, 9389 in 2017, 12,698 in 2018, and 25,361 in 2019. Procedures were done in patients with higher number of chronic comorbidities including Prior myocardial infarction (MI), percutaneous coronary intervention, coronary artery disease, heart failure, hypertension, valvular disease, anemia, obesity, chronic lung disease, chronic kidney disease, diabetes, and obstructive sleep apnea (P<0.001). The rate of complications showed a trend toward reduction from 8.2% in 2016 to 7.1% in 2019 (Ptrend=0.006). Bleeding-related complications were significantly reduced for the year 2019 compared with 2016 (4.7% vs 5.5% respectively, Ptrend=0.024). This was primarily driven by fewer hemorrhagic strokes, major bleeds, and blood transfusion procedures. Hospitals with a higher volume of procedures had decreased mortality rates (aOR:0.89, CI0.85-0.93, P<0.0001). Mortality rates did not differ between different years (0.2%). This large NRD study shows there is an inverse relationship between hospital volume and odds of mortality for pLAAC procedures. The number of patients with chronic comorbidities undergoing pLAAC is increasing. Complication rates have been consistently decreasing. Despite this, there was no significant change in mortality.

PO-01-047 EVALUATION OF EARLY REMOVAL OF FIGURE-OF-EIGHT SUTURE POST LEFT ATRIAL APPENDAGE CLOSURE DEVICE IMPLANTATION

Left atrial appendage closure device implantation (LAAC) is being performed increasingly in appropriate pts for stroke prevention. We report single center experience in outcomes in patients (pts) prior to and after implementation of a strategy of early (2 hr) removal of figure-of-eight (FO8) suture post LAAC device implantation. To assess if early removal of FO8 suture is safe post LAAC device implantation. We reviewed charts of consecutive pts who underwent LAAC device implantation between May, 2021 – Nov, 2022 in whom FO8 suture was used for hemostasis. In Sept, 2022 strategy to remove FO8 suture 2 hr post procedure was implemented. Complications rates were collected post procedure. Comparisons were made using intention to treat analysis. Group A (May 2021 to Aug 2022) included 55 pts (37 males; mean age 77.4 yrs) who had FO8 suture removed > 2hr. Group B (Sept 2022 to Nov 2022) included 24 pts (13 males; mean age 76.6 yrs) who had FO8 suture removed 2 hr post procedure. Baseline characteristics of pts are presented in Table 1. No significant differences were noted in rate of complications prior to discharge (Group A vs Group B, 7 vs 3; p 0.97). In Group B, 2 minor complications, not requiring significant intervention, were noted prior to discharge and one pt stayed > 24 hrs in hospital due to non-procedure related clinical issues. ACT levels (Group A vs Group B, 289 vs 325; p 0.018) and antiplatelet use (Group A vs Group B, 32.8 vs 56.3. p 0.000) was higher in Group B. Our data suggests early removal of FO8 suture post LAAC device implantation appears safe.Tabled 1Table 1Group AGroup BP valueTotal pts5524Male (%)6754BMI31.6329.750.23Chads Vasc Score4.384.540.59Has Bled Score3.553.460.70ACT2893250.018Procedure time (min)48.844.70.40Antiplatelet (%)32.8656.34.00Anticoagulant (%)40.0439.920.97 Open table in a new tab

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

Patient undergoing Left atrial appendage closure (LAAC) needs to be kept on oral anticoagulant (OAC) or dual antiplatelet therapy (DAPT) because of the time required for endothelialization of the LAAC device. Post LAAC follow-up usually is usually performed with either a transesophageal echocardiogram (TEE) or cardiac computed tomography (CCTA) at 45 days, 6 months and 12 months to ensure complete closure and endothelialization of the LAA. Contrast flow (CF) behind the LAAC device on CCTA could be indicative of either a peri-device leak (PDL) or intra-device leak due to incomplete endothelialization. Often the contrast flow into the LAA is described as a leak with implications to continued OAC. This study aims to evaluate the utility of LAA-CF on CCTA scan to predict lack of endothelialization after endocardial LAA closure and its association with peri-device leaks (PDLs). Consecutive patients who underwent LAAC at our center from June 2021 to September 2021 and had follow up CCTA at 45 days, 6 months and 12 months were included in the study. Patients who were follow up with TEE were excluded. Rate of LAA-CF was calculated. LAA-CF was defined as radiodensity > 100 HU (Hounsfield units) of the LAA separated from the device, or contrast opacification ≥ 25% of the left atrium with the presence of any LAA opacification compared with the pre-LAAC cardiac CT. Of 45 patients, 62% had Watchman FLX (n= 28) and 38% had Amplatzer Amulet (n=17) implantation. Mean age of the cohort was 74.6 + 9.3 years and 72% were males. At 45 day follow up CCTA, 40% (n=18) had LAA-CF of which 56% (n=10) had PDL whereas 44% (n=8) had no PDL. On 6 month follow up LAA-CF persisted in 44% (n=8/18) with 62.5% (n=5/8) having PDL. However, at 12 months LAA-CF persisted in only one patient who had a leak of 7 mm (Table). There were no systemic thromboembolic events. Although numbers were small Amulet had higher LAA-CF than Watchman FLX probably related to large outer disc surface area. Delayed LAA-CF is common after LAAO and is a reflection of poor endothelialization than a true PDL. It has no real long term clinical implications.

CE-452771-2 MANAGING PERI-DEVICE LEAKS AFTER LEFT ATRIAL APPENDAGE CLOSURE USING ENDOVASCULAR COILS AND/OR PLUGS

Peri-device leak (PDL) after percutaneous LAA closure (LAAC) has been associated with an elevated risk for thromboembolism. PDL closure has been reported achievable using coils to obliterate the space behind the LAAC device, or elimination of the leak itself with a plug device. To present our center experience of PDL closure with endovascular coils or plugs in patients receiving LAAC between 2015 to 2022. We performed a retrospective chart review of patients who underwent PDL closure after LAAC with the Watchman or Watchman-FLX devices. After transeptal puncture, under ICE/TEE guidance, PDLs were closed with either endovascular coils (Terumo Inc) or plugs (Amplatzer, Abbott Inc), or a combination of both. We collected data on the number/size and method of PDL closure In total, the cohort included 45 pts: age 73±8.8 yrs, male 30 pts (67%), PAF 23 pts (51%), CHADS-VASc 4±1.5, HAS-BLED 2.8±1.1. The implanted device was Watchman in 34 pts and Watchman-FLX in 11 pts, with implant parameters: maximum LAA size 21±3.6 mm, LAAC device size 28±2.5 mm, and device compression 18%±5.1%. The PDL size was 3.9±1.5 mm (range 1.2 to 7 mm), and were identified at 12.4±14.3 mo post-implantation (range 2-72 mo). PDL closure was successful in 40 of 45 pts (89%) using coils alone in 21 of 40 pts (52.5%), plugs alone in 12 of 40 pts (30%), a combination in 6 of 40 pts (15%), and radiofrequency ablation in 1 pt (2.5%). For coils, an average of 4.6 coils were used. For plugs, an average of 1.2 plugs/pt were used (ADO2-11 pts, AVP2-7 pts, ASD-2 pts). The 5 PDL closure “failures” included: 1 aborted due to anatomic difficulty in accessing the leak, 3 aborted cases due to diminutive leak by invasive assessment, and 1 aborted due to pericardial effusion (percutaneously drained without sequalae). One pericardial effusion was successfully drained and the procedure successfully completed. Before PDL closure, over a mean follow-up of 38.5 mo post-LAAC, 7 ischemic strokes occurred (5.1%/100 pt-yr); but after PDL closure, there were no subsequent strokes. These data indicate that closure of PDLs with the use of either an endovascular coil, plug or a combination, is technically feasible in ∼90%, has a low procedural risk, and may reduce the risk of subsequent thromboembolism.

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

Morphological variation in left atrial appendage (LAA) and structural mismatch between LAA ostia and LAA closure (LAAC) devices can result in incomplete closure and peri-device leak (PDL) post-LAAC. Prior data had suggested that PDL of ≤5 mm was not clinically relevant, but recent larger datasets have demonstrated that any PDL after LAAC is associated with a higher thromboembolic risk. But these data were largely obtained at a time before LAAC To determine the incidence and impact of PDL in a large single-center experience. We performed retrospective analysis of 650 consecutive patients who underwent LAAC (with Watchman/Watchman FLX; Boston Scientific Inc). PDL presence was assessed from the 1-yr follow-up TEEs or cardiac CT scans (1-yr imaging is routine in our practice). A multivariable analysis was conducted to assess for predictors of PDL including age, gender, congestive heart failure, chronicity of AF (paroxysmal vs non-paroxysmal) and the LAAC device iteration (initial generation vs FLX). Between 3/2015 - 12/2021, a total of 650 patients underwent LAAC at our center: age 75.8±8.9 yrs, male 64%, CHA2DS2-Vasc 4.2±1.4. One-year TEE/CT imaging identified PDLs in 146 (22.5%) patients, with PDL size being 2.2±1.9 mm. The only multivariable predictor of PDL was the presence of non-paroxysmal AF (adjusted OR 1.9, 95% CI: 1.3- 2.9, p = 0.002). During the study follow up period, there were a total of 35 (5.4%) strokes. The presence of any PDL at 1-yr was associated with a higher stroke risk (OR: 4.9, 95% CI 2.2-10.6, p < 0.001) than in the absence of PDL. PDLs are not uncommon after LAAC, and when present, were associated with a substantially higher risk for thromboembolism. Non-paroxysmal AF predicted PDL, perhaps because of adverse LAA remodeling in these patients. Our findings raise the question of the potential utility of PDL closure/coiling or reinitiating anticoagulation (perhaps low dose) in patients with persistent PDL after LAAC.

PO-03-195 AMULET IMPLANTATION AFTER FAILED WATCHMAN: A RETROSPECTIVE REVIEW WITH COMMENTARY ON IMPLICATIONS OF LAA ANATOMY

Watchman and Amulet are both approved and effective left atrial appendage closure (LAAC) devices, each utilizing different design and characteristics to prevent AF-related strokes. Failed LAAC is a complication often seen with complex LAA anatomy particularly with inexperienced implanters. A patient may have LAA measurements that do not screenfail but are still unable to securely or completely occlude the LAA. Watchman received FDA approval in 2015, Amulet in 2021. Thus, Watchman has become the more widely used device in the United States. At a single center with 7 implanters, we have found that Amulet is often successfully implanted after failed Watchman. We present our experience as well as observations on anatomical characteristics amenable to Amulet implantation after failed Watchman. We present our experience in Amulet implantation after failed watchman. At a single center with experienced implanters, 27 patients failed Watchman implant were then sent for LAAC with Amulet. A failed Watchman was defined as a patient who did not screenfail but could not meet deploy with stability, significant leaks, or uncovered trabeculations or lobes. Of the 27 patients who failed Watchman, 26 (96%) were successfully implanted with Amulet. Upon retrospective review of the LAA that failed both Amulet and Watchman should have failed preop screening and not attempted; the short depth to the top of the trabeculations at the deepest point did not provide adequate room for either device to deploy. The reasons for Watchman failure were all anatomical in nature and can be subdivided into four basic categories each with their own mechanism of failure: 1. Shallow / Insufficent depth 2. Appropriate depth with intervening trabeculations 3. Bilobed appendages 4. Wide, with posterior sloping trabeculations above implant plane No perioperative complications or postoperative dislodgment or leak were observed in these cases. These findings indicate that for many, failed Watchman implant does not mean that LAAO is futile. There are at least four general categories of LAA anatomy that are amenable to Amulet implantation when Watchman cannot be succesfully or safely deployed. The design of Amulet tends to allow successful implanted in these four challenging anatomical variations unable to be closed by Watchman, even for providers more experienced with Watchman. These results suggest that preoperative imaging may be helpful to preemptively anticipate which device may be more suitable for closure.

PO-03-140 CARDIAC MAGNETIC RESONANCE IMAGING VERSUS CARDIAC COMPUTED TOMOGRAPHY ANGIOGRAPHY FOR LEFT ATRIAL APPENDAGE SIZING AND THROMBUS ASSESSMENT PRIOR TO DEVICE CLOSURE

Preoperative imaging for left atrial appendage closure (LAAC) is essential for LAA sizing and thrombus assessment. Transesophageal echocardiography (TEE) and cardiac computed tomography angiography (CCTA) have been utilized to date for this purpose. During the recent global iodine contrast shortage, cardiac magnetic resonance imaging (CMR) was utilized as an alternative imaging modality. The purpose of this study was to assess CMR vs CCTA for preoperative LAA sizing and thrombus assessment prior to LAAC. This retrospective study conducted at The Ohio State University Wexner Medical Center included all patients who underwent preoperative CMR or CCTA for LAAC with Watchman FLX or Amplatzer Amulet between May 2022 and October 2022. Primary measures were accuracy of predicted device size, accuracy of thrombus detection/exclusion, and mean difference in maximum LAA ostial diameter and depth as compared to intraoperative TEE. An area-derived diameter approach was utilized with CMR and CCTA to obtain the maximum diameter in order to prevent oversizing highly elliptical ostial shapes. The radius (r) was calculated based on device design. For the octadecagonal Watchman FLX, area = r2 x 3.0782. For the circular Amulet, area = r2 x 3.1416. 75 patients underwent LAAC, and 25 (33%) vs 50 (67%) underwent preoperative CMR vs CCTA respectively. Demographics were notable for age 75 ± 7 years, 32 (43%) females, 31 ± 7 kg/m2 body mass index, 53 ± 9% left ventricular ejection fraction, and 4 ± 1 CHA2DS2-VASc. 64 (88%) and 9 (12%) patients underwent Watchman FLX and Amplatzer Amulet implantation respectively. There was no significant difference with CMR vs CCTA in accuracy of predicted device size (CMR: 16 (64%) vs CCTA: 26 (70%) patients, p=0.604) and accuracy of thrombus assessment (CMR: 22 (88%) vs CCTA: 46 (92%) patients, p=0.680). Among the 57 (76%) cases completed with intraoperative TEE guidance where LAA measurements were obtained, there was no significant difference with CMR vs CCTA in the mean difference in maximum LAA ostial diameter (CMR: 2.9 ± 2.0 vs CCTA: 2.6 ± 2.5 mm, p=0.699) and mean difference in maximum LAA depth (CMR: 9.5 ± 8.5 vs CCTA: 10.8 ± 7.5 mm, p=0.620) as compared to intraoperative TEE. Figure 1 demonstrates LAAC device sizing using multiplanar reconstruction with oblique views of the LAA on CCTA (A-C) and CMR (D-F). CMR and CCTA were comparable for LAA sizing and thrombus assessment prior to LAAC.

Percutaneous left atrial appendage closure in patients with hypertrophic cardiomyopathy and persistent atrial fibrillation: 3-year-followed case series.

Hypertrophic cardiomyopathy (HCM) patients with atrial fibrillation (AF) are at high risk for stroke. Left atrial appendage closure (LAAC) is a promising alternative for stroke prevention in AF patients. We aimed to review the clinical outcomes of patients with AF and HCM at our center. We reviewed 673 patients who underwent LAAC implantation from 2014 to 2021 in a tertiary center, of whom 15 had HCM. AF Patients with HCM were compared with sex and age matched controls who also underwent LAAC. From 2014 to 2021, 673 AF patients received LAAC in a single center, of whom, 15 patients had HCM. LAAC devices were successfully implanted in 14 HCM patients and 59 patients in the control group. During the follow-up period (median 1151 days range: 132-2457 days), 2 HCM patient had ischemic strokes. There were another 2 HCM patients who had sudden cardiac death (SCD). Compared with the control, HCM patients had higher cumulative rate of combined death and stroke (26.67% vs 3.33%, P = .024). In our initial clinical experience, the cumulative stroke and death rate of the HCM patients was significantly higher than that of the non-HCM patients.