Residual Leak Research Articles

4-year follow-up results of percutaneous closure of atrial septal defect with the total biodegradable poly-L-lactic acid device: date from a prospective, single-center trial

Abstract Background The poly-L-lactic acid (PLLA) device is a novel, total biodegradable occluder dedicated to percutaneous closure of atrial septal defect (ASD) .Closure of ASD with the PLLA device has proven to be relatively safe and effective in our preclinical and first-in-human studies. Objective The aim of the study was to evaluate long-term safety and efficacy of the PLLA device in percutaneous closure of ASD in a large cohort of patients. Methods A prospective study enrolling patients who had a clinically significant ASD was conducted in our institution from May 2018 to August 2019. Percutaneous ASD closure was undertaken with the PLLA device. Evaluations were scheduled pre-hospital discharge and again at 1, 3, 6, 12, 24, 36 and 48 months post implantation. Primary endpoints were a composite of clinical success, including closure success and no major complications at the 48-month follow-up evaluation. Results A total of 52 patients (35 children, 55.8% females, median age 7.55 years, median weight 28.75Kg) underwent an attempt at percutaneous ASD closure with PLLA device. Successful device implantation was achieved in 50 (96.1%) of 52 patients with delivery attempts. All the 50 patients (100%) completed 4-year follow-up visit. Closure success at 4-year follow-up were 84% (42/50), with 8 patient (16%) reported to have clinically significant leaks, including 2 large residual leaks, 5 moderate residual leaks, and 1 small residual leak. 10 complications occurred, with 1 event of cardiac arrhythmia during procedure, and 9 follow-up events, consisting in cardiac arrhythmias (n=6), moderate or large mitral regurgitation (n=2), and headache (n=1). Conclusion Percutaneous ASD closure with PLLA device in human seems to be safe. However, increased occurrence of residual leaks overtime indicated that long-term efficacy of PLLA device in human was sub-optimal.TTE follow-up of a case with PLLA device

Combined PVI and LAAC is feasible using RFA or PFA in a canine model despite acute tissue edema in PFA versus RFA

Abstract Background Combined procedure with pulmonary vein isolation (PVI) using thermal energy followed by left atrial appendage closure (LAAC) has been used in select patient populations with positive results. Pulsed field ablation (PFA) is a novel non-thermal ablation modality that ablates cardiac tissue by irreversible electroporation. The effect of PFA on cardiac tissue and its interaction with a LAAC device in a single procedure has not been studied. Purpose To evaluate using transesophageal echo (TEE) imaging the acute tissue response following ablation by PFA compared to radiofrequency ablation (RFA) and its interaction with the WATCHMAN FLX Pro LAAC device when used in a combined procedure in a healthy canine model. Methods Nine mongrel canines underwent PVI using either circumferential PFA (FARAPULSE) energy application (n=6) or RFA energy (n=3). TEE imaging was obtained at the time of the procedure before and immediately after ablation energy application. The general appearance and echogenicity of the left lateral ridge was assessed and the os of the left atrial appendage (LAA) was measured in the four standard TEE views (0, 45, 90, and 135 degrees). Decisions about device sizing were made accordingly. PVI was evaluated by entry and exit block in all veins except the right inferior pulmonary vein (RIPV), which was not ablated. Following ablation, the LAAC device was implanted using TEE and fluoroscopic guidance in all animals and the percentage of compression measured. PASS criteria were assessed before the release of each device. All animals received dual antiplatelet therapy post implant. Results PVI was confirmed in all animals (except RIPV which was not targeted for ablation) using PFA and RFA. LAA dimensions (at device landing site) did not change substantially after RF ablation. With PFA, there was evidence of more diffuse edema and decrease in LAA diameter (Table). The LAAC device was implanted successfully after meeting PASS criteria in all animals within 30 minutes post ablation. The device size was decreased following PFA in two (2/6) animals, whereas there was no deviation from baseline measurements in device size for any of the RFA animals. Average LAAC device compression was higher for PFA versus RFA animals (Table). TEE post implant confirmed absence of any peri-device leaks in all animals. Conclusion Concomitant PVI using PFA (FARAPULSE) and LAAC (WATCHMAN FLX Pro) is feasible with 100% success and no residual acute peri-device leak. In the canine model, PFA is associated with more diffuse edema compared to RFA, which might affect device sizing. Long term consequences of this acute edema need to be evaluated in serial imaging and future larger clinical trials.Table

Prevention of thromboembolic events in atrial fibrillation patients with persistent leaks following the watchman implantation

Abstract Introduction Peri-device leak is not uncommon after percutaneous occlusion of left atrial appendage using the Watchman device. Prior studies have reported the clinical relevance of small leaks (<5mm) as they were associated with a significant increase in ischemic events. Purpose We evaluated the prevalence of stroke in patients with post-watchman leaks on half-dose non-vitamin K oral anticoagulants (HD-NOAC) vs antiplatelet therapy (APT). Methods This consecutive series included post-watchman cases that had a residual leak of ≤5 mm at the 45-day echocardiogram and were unwilling to undergo any leak-closure procedure. Based on their subsequent antithrombotic therapy, they were classified into group 1: HD-NOAC and group 2: dual-APT for 6 months followed by Aspirin only. Patients were closely monitored for thromboembolic (TE) events via telemedicine. Stroke/transient ischemic attacks that occurred while the patients were in full compliance with the anti-thrombotic therapy, were counted as the reportable TE events. Results A total of 141 (age: 66.89± 8.76 years, male: 88 (62.4%), CHA2DS2-VASc score: 3.41 ± 1.56, HAS-BLED: 3.72 ± 1.01) and 154 (age: 72.45 ±7.05 years, male: 99 (64.3%), CHA2DS2-VASc score: 3.75 ± 1.61, HAS-BLED: 3.89 ± 1.05) patients were included in group 1 and 2 respectively. All leaks were between 3-5 mm. TE events were reported in 2 (2/141, 2.12%) patients in group 1 and 9 (9/154, 5.8%) in group 2 while being on antithrombotic therapy (p=04). No residual neurological deficits were detected in the 2 patients from group 1 contrary to the 9 subjects in group 2 that had neurological deficits persistent at follow-up. Of note, 8 (5.6%) patients in group 1 experienced stroke after discontinuing the drug for other medical procedures or due to poor compliance. Conclusion Under full compliance, HD-NOAC is associated with significantly lower TE rate compared to the APT therapy in post-watchman cases with persistent leaks of ≤5 mm. However, discontinuation of the HD-NOAC increases the stroke-risk to a comparable level.

The Use of Synthetic, Nonabsorbable Graft for Middle Fossa Repair in Patients With Spontaneous Cerebrospinal Fluid Leak: A Pilot, Prospective Study.

To evaluate the efficacy of a nonabsorbable, synthetic graft for the reconstruction of spontaneous middle fossa (sMF) cerebrospinal fluid (CSF) leaks. Six adult patients (age ≥16 yr) who had sMF CSF leaks surgically repaired within an 18-month period at a single university hospital using synthetic, nonbiological, nonabsorbable graft (Neuro-Patch) and a retrospective control group of five patients undergoing multilayer MF repair with autologous grafts. MF repair through a combined transmastoid/MF approach using Neuro-Patch or multilayer autologous grafts. The incidence of postoperative leak within 6 months postoperatively was the main outcome measure; we also recorded the need for lumbar drain, additional hearing loss, length of inpatient stay, body mass index, previous meningitis, preoperative increased intracranial pressure, and age. In the Neuro-Patch group, there was no postoperative CSF leak without the need for lumbar drain. We observed no additional hearing loss; patients were monitored for 2 days without any readmissions. Increased intracranial pressure (four of six), previous episodes of meningitis (two of six) or obesity (five of six) did not affect patient outcomes. Demographic and prognostic factors were the same for the control group. However, one patient needed lumbar drain postoperatively because of residual leak; lumbar drain was used in one more case (two of five cases), whereas three of five patients had to stay for longer than 2 days (5 d). Our pilot study suggests the use of Neuro-Patch via combined transmastoid/MF approach as an effective technique with minimum, if any morbidity; it could be of particular benefit for patients with larger MF dura defects. A larger number of patients are required to strengthen the evidence.

Venous-Only Transcatheter Closure: A Safe and Effective Strategy for Patent Ductus Arteriosus

Objectives: This study aimed to assess the feasibility and effectiveness of transcatheter device closure of patent ductus arteriosus (PDA) exclusively through an isolated venous route. Methodology: A retrospective descriptive study was conducted at the Rawalpindi Institute of Cardiology. Patient data from 2019 to 2023 undergoing PDA closure using transcatheter devices were analyzed. PDA diagnosis was established via echocardiography, and the procedure was performed solely through a venous line under fluoroscopy, omitting the traditional method of using both arterial and venous lines. Results: A total of 212 patients underwent transcatheter PDA closure through a venous-only route, with ages ranging from 6 months to 14 years. The mean weight was 10.07 kg (range: 5 kg to 27 kg, SD 4.43). The average procedure time was 30 ± 10.3 minutes (range: 15.0 to 65 minutes), and fluoroscopy time was 5.4 ± 3.18 minutes (range: 2.1 to 19 minutes). Immediate closure was achieved in all patients, with no residual leaks or device embolization observed. Additionally, there were no reported complications such as arrhythmia, vascular access issues, or significant blood loss. No cases of aortic or pulmonary stenosis were identified, and no deaths occurred. All patients were discharged within 48 hours post-procedure. Conclusion: Transcatheter closure of PDA exclusively through the venous route, without the use of an arterial line, demonstrates itself as an effective and safe method for PDA closure.

Interventional atrial appendage occlusion: residual leaks must be avoided!

Interventional atrial appendage occlusion: residual leaks must be avoided!

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

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

Short Term Outcomes of Transcatheter Ventricular Septal Defect Device Closure at Tertiary Cardiac Care Center

Objective: To determine post procedural immediate and short-term outcomes of transcatheter Ventricular Septal Defect (VSD) device closure. Study Design: Longitudinal Cross-sectional study. Place and Duration of Study: Pediatric Cardiology Unit at Tertiary Cardiac Care Centre, Rawalpindi, Pakistan, from Feb to Oct 2022. Methodology: Total of 62 patients fulfilling inclusion and exclusion criteria who underwent transcatheter VSD device closure were retrospectively identified from our institutional database by non-probability consecutive sampling technique. Preprocedural evaluation [Transthoracic Echocardiography (TTE) &amp; Electrocardiography(ECG)], procedural details and immediate post procedure outcomes were documented. Follow-up evaluations were done at 6 and 12 months. It included clinical examination, TTE and 12 lead ECG. New onset and status of old complications were documented in each visit. SPSS version 24.00 was used to analyze data. Chi-square test was used to find association between study variables. p-&lt;0.05 wasconsidered significant. Results: Sixty-two patients were followed up for upto 1 year after VSD device closure. Mean VSD size on Echo was 4.612.52mm. Successful closure was obtained in 54(87.0%) of cases out of 62. Complications documented during and immediately after procedure were transient arrythmias in 22(35.5%), residual leaks in 9(14.6%) which reduced to 3(4.8%) on 12 months follow up, device redeployment in 3(4.8%), complete heart block (cAVB) in 1(1.6%), device embolization in 1(1.6%), hemolysis in 2(3.2%), contrast related complications in 1(1.6%), aortic regurgitation (AR) in 4(6.4%). Death occurred in 1(1.6%) patient secondary to contrast related complications. Conclusion: Transcatheter VSD closure is a promising and safe treatment modality with high success rate. Complications ..

Residual leaks following percutaneous left atrial appendage occlusion and outcomes: a meta-analysis.

Residual leaks are not infrequent after left atrial appendage occlusion. However, there is still uncertainty regarding their prognostic implications. The aim of this study is to evaluate the impact of residual leaks after left atrial appendage occlusion. A literature search was conducted until 19 February 2023. Residual leaks comprised peri-device leaks (PDLs) on transoesophageal echocardiography (TEE) or computed tomography (CT), as well as left atrial appendage patency on CT. Random-effects meta-analyses were performed to assess the clinical impact of residual leaks. Overall 48 eligible studies (44 non-randomized/observational and 4 randomized studies) including 61 666 patients with atrial fibrillation who underwent left atrial appendage occlusion were analysed. Peri-device leak by TEE was present in 26.1% of patients. Computed tomography-based left atrial appendage patency and PDL were present in 54.9% and 57.3% of patients, respectively. Transoesophageal echocardiography-based PDL (i.e. any reported PDL regardless of its size) was significantly associated with a higher risk of thromboembolism [pooled odds ratio (pOR) 2.04, 95% confidence interval (CI): 1.52-2.74], all-cause mortality (pOR 1.16, 95% CI: 1.08-1.24), and major bleeding (pOR 1.12, 95% CI: 1.03-1.22), compared with no reported PDL. A positive graded association between PDL size and risk of thromboembolism was noted across TEE cut-offs. For any PDL of >0, >1, >3, and >5 mm, the pORs for thromboembolism were 1.82 (95% CI: 1.35-2.47), 2.13 (95% CI: 1.04-4.35), 4.14 (95% CI: 2.07-8.27), and 4.44 (95% CI: 2.09-9.43), respectively, compared with either no PDL or PDL smaller than each cut-off. Neither left atrial appendage patency, nor PDL by CT was associated with thromboembolism (pOR 1.45 and 1.04, 95% CI: 0.84-2.50 and 0.52-2.07, respectively). Peri-device leak detected by TEE was associated with adverse events, primarily thromboembolism. Residual leaks detected by CT were more frequent but lacked prognostic significance.

Feasibility of transcatheter device closure of secundum atrial septal defect under transthoracic echocardiography guidance.

Objective: To determine the usefulness and safety of transthoracic echocardiography (TTE) imaging for real time guidance in transcatheter device closure of atrial septal defect (ASD) secundum. Study Design: Cross-sectional study. Setting: Department of Paediatric Cardiology, CPEIC, Multan, Pakistan. Period: January 2022 to December 2023. Material &amp; Methods: Patients of both genders aged above 3 years with clinical and echocardiographic evidence of ASD secundum with significant left to right shunt were analysed. All cases had morphologically suitable margins of defect confirmed on TTE. Usefulness and safety of intra-procedure and immediate post-procedure transcatheter device closure of secundum ASD were noted. Results: In a total of 34 patients, 20 (58.8%) were female and 14 (41.2%) male. The mean age was 21.32±17.21 years. The TTE findings revealed that the mean ASD side was 17.47±4.32 mm. Aortic margins were deficient among 28 (82.4%) cases. The mean fluoroscopy and procedure time were 9.29±6.98 minutes and 49.91±39.76. Residual leak was noted in one (2.9%) cases while none of the cases were observed to have superior vena cava, inferior vena cava or pulmonary vein obstructions. Post-procedure, transient supraventricular tachycardia (SVT) arrhythmia was the most common type of complication reported among 2 (5.9%) cases. None of the cases needed any kind of emergency surgical exploration. No cases of pericardial effusion were found. No mortality was reported. Conclusion: Transcatheter device closure of secundum atrial septal defect was found to be effective and safe using TTE.

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: &amp;gt;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: &amp;gt;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 &amp;gt;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.

Left Atrial Appendage Occlusion Under Miniaturized Transesophageal Echocardiographic Guidance and Conscious Sedation: Multicenter European Experience

BackgroundLeft atrial appendage occlusion (LAAO) procedures are widely guided by standard transesophageal echocardiography (TEE) probes, requiring general anesthesia in most patients. The use of miniaturized TEE probes allows for LAAO guidance under local anesthesia and offers an attractive imaging alternative to standard TEE probes. ObjectivesThe aim of this study was to assess the safety and efficacy of miniaturized TEE probes for procedural guidance of LAAO. MethodsMulticenter retrospective observational study of LAAO procedures performed under miniaturized TEE guidance and conscious sedation. The primary efficacy endpoint was technical success. The secondary efficacy endpoint was procedural success (technical success without major periprocedural complications). The safety outcome was a composite of major periprocedural complications. ResultsA total of 546 consecutive LAAO procedures were performed in 5 European centers. Technical success was achieved in 534 (98.0%) patients. Sixteen major periprocedural complications occurred in 15 (2.9%) patients, yielding a procedural success rate of 97.0%. Conversion to general anesthesia was required in 4 (0.7%) patients. Short-term imaging follow-up was available in 422 patients with an incidence of major (>5 mm) TEE-detected residual leaks of 0.7%, complete LAA occlusion of 82.2% on cardiac computed tomography, and device-related thrombus of 5%. As compared with procedural 2-dimensional imaging for device sizing, preprocedural assessment by 3-dimensional imaging resulted in improved technical success (100% vs 95.0%; P < 0.001). ConclusionsLAAO under conscious sedation and miniaturized TEE guidance is safe and feasible with a high rate of technical success and a low rate of periprocedural complications.

Device-related thrombus after left atrial appendage occlusion in patients with atrial fibrillation: a prospective follow-up

Aim. To study the incidence, predictors, and clinical outcome of device-related thrombus (DRT) after left atrial appendage occlusion (LAAO) in patients with atrial fibrillation (AF).Methods. A prospective observational study included 120 patients with non-valvular AF who underwent LAAO with Watchman (n=92) and Amplatzer Amulet (n=28). The presence of device-related thrombus (DRT) was assessed at visits 45 days, 6 months, 1 year, 2 years, 3 years after implantation by transesophageal echocardiography.Results. A total of 11 (9.2%) patients had DRT during the follow-up period. The greatest number of thrombosis was observed after 45 days (n=4) and after 6 months (n=4). There was no significant difference in the incidence of DRT between device types. Independent predictors of thrombosis were: history of myocardial infarction (hazard ratio (HR) 12.88 [95% confidence interval (CI) 3.21-51.62]; p&lt;0.001), chronic heart failure (HR 8.83 [95% CI 1.91-40.77]; p=0.005), residual leak size &gt;5 mm in the early postoperative period (HR 6.13 [95% CI 2.53-14.86]; p&lt;0.001) and the degree of spontaneous echo contrast during the initial examination (HR 9.09 [95% CI 1.36-60.58], p=0.023). There were no cases of thromboembolic complications associated with DRT. One patient developed a non-fatal stroke at 35 weeks of follow-up, while DRT was detected at the visit at the end of the 3rd year of follow-up.Conclusion. DRT after LAAO was observed in the early and long-term follow-up periods. This event was associated with the baseline patients’ characteristics and post-procedural aspects with no dependence on type of antithrombotic therapy.

Intracardiac echocardiography-guided left atrial appendage occlusion: The path to independence

Introduction and ObjectivesTransesophageal echocardiography (TEE) has been the standard method for guiding left atrial appendage occlusion (LAAO) procedures. Recently, intracardiac echocardiography (ICE) has emerged as an alternative to TEE due to several advantages, particularly the avoidance of general anesthesia. This analysis aims to assess the safety, feasibility and efficacy of ICE-guided LAAO procedures. MethodsWe performed a retrospective analysis of ICE-guided LAAO procedures, including a comparison of embolic and bleeding events with the predicted standard scores and a comparison with TEE-guided procedures. ResultsA total of 88 patients underwent echocardiography-guided percutaneous LAAO (43 patients with TEE and 45 with ICE), mean age 74.9 years, 68.2% male. In the ICE-guided population, the technical success rate was 93% and the major complication rate was 8.8%. During follow-up, yearly stroke and major bleeding rates were 1.4% and 8.4%, respectively, compared to the 4.0% and 8.7% predicted by the CHA2DS2-VASc and HAS-BLED scores. In the TEE versus ICE analysis (similar baseline characteristics), no statistically significant differences were seen regarding technical success (95.3% vs. 93.3%), procedure-related complications (14.0% vs. 8.9%), device thrombus (2.3% vs. 0%), residual minor peridevice leaks (14.0% vs. 24.4%), one-year all-cause mortality (9.3% vs. 4.4%), stroke (9.3% vs. 2.2%) or major bleeding events (9.3% vs. 11.1%). ConclusionICE-guided LAAO was a safe and effective therapeutic strategy in a high embolic and bleeding risk population, compared to the event rates predicted by the CHA2DS2-VASc and HAS-BLED scores. The ICE-guided procedure compared well to TEE-guided procedures regarding procedure feasibility, safety, and efficacy.

Transcatheter Left Atrial Appendage Exclusion: Preclinical and Early Clinical Results With the Laminar Device

BackgroundThe Laminar device rotates and closes the left atrial appendage (LAA) using an integrated ball and lock that excludes and eliminates the LAA pouch. There is a low device surface area, minimizing the risk of peridevice leak (PDL) and device-related thrombus (DRT) formation. ObjectivesThis study evaluates the safety and efficacy of the Laminar LAA exclusion device in healthy animals and human subjects with nonvalvular atrial fibrillation at risk of ischemic stroke and systemic thromboembolism. MethodsThe preclinical study implanted the Laminar device into canine subjects that underwent transesophageal echocardiography (TEE) and fluoroscopic evaluation, followed by necropsy and histological assessment at 45 and 150-days post-implant. The early clinical study implanted the device in human subjects, followed to 12 months postimplantation. Procedural success was defined as device implantation in the intended location without residual LAA leak >5 mm as seen by TEE. Safety endpoints included freedom from stroke, systemic embolism, pericardial effusion, or tamponade, life-threatening/major bleeding, or death. ResultsThe Laminar device was successfully implanted in 10 canines. In all animals at 45 days and 150 days, no PDL or DRT was found, and histological examination showed fully closed LAAs covered with neo-endocardium. The device was successfully implanted in 15 human subjects with no safety events out to 12 months postimplantation. All subjects had successful protocol-defined LAA closure without DRT at 45 days by TEE and computed tomography, which remained stable through 12 months’ follow-up. ConclusionsThe preclinical and early clinical results demonstrate a promising safety and efficacy profile for the Laminar LAA exclusion device.

Safety and efficacy of transcatheter closure of Fontan fenestration with atrial septal occluder

Objective: To assess the safety and efficacy of transcatheter fenestration closure following Fontan procedure with an atrial septal occluder. Methods: This is a retrospective study. The study sample consists of all consecutive patients who underwent closure of a fenestrated Fontan baffle at Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine between June 2002 and December 2019. The indications of Fontan fenestration closure included that normal ventricular function, targeted drugs for pulmonary hypertension and positive inotropic drugs were not required prior the procedure; and the Fontan circuit pressure was less than 16 mmHg (1 mmHg=0.133 kPa) and no more than a 2 mmHg increase during test occlusion of the fenestration. Electrocardiogram and echocardiography were reviewed at 24 hours, 1, 3, 6 months and annually thereafter post procedure. Follow-up information including clinical events and complications related to Fontan procedure was recorded. Results: A total of 11 patients, including 6 males and 5 females, aged (8.9±3.7) years old were included. The types of Fontan were extracardiac conduits (7 cases) and intra-atrial duct (4 cases). The interval between percutaneous fenestration closure and the Fontan procedure was (5.1±2.9) years. One patient reported recurrent headache after Fontan procedure. Successful fenestration occlusion with atrial septal occluder was achieved in all patients. Compared with prior closure, Fontan circuit pressure ((12.72±1.90) mmHg vs. (12.36±1.63) mmHg, P<0.05), and aortic oxygen saturation ((95.11±3.11)% vs. (86.35±7.26)%, P<0.01) were increased. There were no procedural complications. At a median follow-up of (3.8±1.2) years, there was no residual leak and evidence of stenosis within the Fontan circuit in all patient. No complication was observed during follow-up. One patient with preoperative headache did not have recurrent headache after closure. Conclusions: If the Fontan pressure is acceptable by test occlusion during the catheterization procedure, Fontan fenestration could be occluded with the atrial septum defect device. It is a safe and effective procedure, and could be used for occlusion of Fontan fenestration with varying sizes and morphologies.

The Amplatzer duct occluder (ADOII) and Piccolo devices for patent ductus arteriosus closure: a large single institution series.

Evaluate Piccolo and ADOII devices for transcatheter patent ductus arteriosus (PDA) closure. Piccolo has smaller retention discs reducing risk of flow disturbance but residual leak and embolization risk may increase. Retrospective review of all patients undergoing PDA closure with an Amplatzer device between January 2008 and April 2022 in our institution. Data from the procedure and 6 months follow-up were collected. 762 patients, median age 2.6 years (range 0-46.7) years and median weight 13 kg (range 3.5-92) were referred for PDA closure. Overall, 758 (99.5%) had successful implantation: 296 (38.8%) with ADOII, 418 (54.8%) with Piccolo, and 44 (5.8%) with AVPII. The ADOII patients were smaller than the Piccolo patients (15.8 vs. 20.5 kg, p < 0.001) and with larger PDA diameters (2.3 vs. 1.9 mm, p < 0.001). Mean device diameter was similar for both groups. Closure rate at follow-up was similar for all devices ADOII 295/296 (99.6%), Piccolo 417/418 (99.7%), and AVPII 44/44 (100%). Four intraprocedural embolizations occurred during the study time period: two ADOII and two Piccolo. Following retrieval the PDA was closed with an AVPII in two cases, ADOI in one case and with surgery in the fourth case. Mild stenosis of the left pulmonary artery (LPA) occurred in three patients with ADOII devices (1%) and one patient with Piccolo device (0.2%). Severe LPA stenosis occurred in one patient with ADOII (0.3%) and one with AVPII device (2.2%). ADOII and Piccolo are safe and effective for PDA closure with a tendency to less LPA stenosis with Piccolo. There were no cases of aortic coarctation related to a PDA device in this study.

PO-03-189 THROMBOEMBOLISM BEFORE VS AFTER PERCUTANEOUS CLOSURE OF PERI-DEVICE LEAKS RESULTING FROM PERCUTANEOUS LEFT ATRIAL APPENDAGE OCCLUSION

Recent studies have indicated that residual peri-device leaks after percutaneous left atrial appendage occlusion (LAAO) portend a higher risk of thromboembolic (TE) events. It is unknown whether eliminating these leaks via endovascular devices (e.g., coils, plugs) would improve clinical outcomes. To determine the TE risk in patients with incomplete LAAO before vs after leak closure with endovascular devices. This international, multicenter registry was designed as a retrospective review of individual prospective registries maintained at each participating center. All patients with peri-device leak≥3mm who underwent percutaneous closure were enrolled. A total of 238 LAAO patients with residual peri-device leak≥3mm were enrolled at 7 centers (age 74±9 years; 66.8% male; CHA2DS2-VASc 4.8±1.4; HAS-BLED 3.4 ± 1.1). The time between LAAO and leak closure was 11±9 months [221 patients-year (PY)]. Leaks were classified as moderate (3-4mm) in 174 patients (73.1%) or severe (≥5mm) in 64 (26.9%) patients. TE events occurred in 22 (9.2%) patients before leak closure, after a median of 8 months (IQR:6-21) post-LAAO (annualized rate: 9.9%). At the time of TE event, 13 (59.1%) patients were on ASA, 4 (18.2%) on warfarin, 4 (18.2%) on DAPT, and 1 (4.5%) on DOAC. Percutaneous leak closure was performed via endovascular coils or other vascular/septal occluders in 186 (78.1%) and 52 (21.9%) patients, respectively. Procedure time was 89±48 min; the mean volume of iodinated contrast medium used was 64±34mL. Major complications occurred in 2.5% (1 stroke, 1 air embolism, 4 pericardial effusions). Follow-up TEE after 3.4±1.9 months revealed complete LAA sealing or a negligible leak in 218 cases (91.6%); the remaining 20 patients had moderate (n=18) or severe (n=2) residual leak. During a mean follow-up after leak closure of 15±9 months (289PY); 9 (3.8%) patients developed TE events (annualized rate: 3.1%). Among them, 7 (77.8%) patients were on ASA, 1 (11.1%) on clopidogrel, and 1 (11.1%) on no antithrombotic therapy. TE incidence was significantly lower after leak closure (Hazard Ratio: 0.30; 95% Confidence Interval: 0.14-0.69; p=0.004). Kaplan Meier survival curves are reported in Figure 1 (log-rank p-value: 0.0023). Peri-device leaks≥3mm following percutaneous LAAO were associated with a high incidence of TE events. Percutaneous leak closure was safe and contributed to a significant thromboembolic risk reduction.

PO-03-137 A HIGH-VOLUME SINGLE CENTER EXPERIENCE OF LAA CLOSURE WITH AMULET VS. WATCHMAN FLX DEVICE

Real world data remains limited in comparing the left atrial appendage occlusion (LAAO) devices with Amulet and the new Watchman FLX. This study aims to report a comparison of short term outcomes of a high volume, single center experience with watchman FLX and Amulet device. Consecutive patients who underwent LAAO using Watchman FLX or Amulet devices from Feb 2020 to July 2022 were included in the study. Institutional NCDR LAAO Registry was used as well as retrospective chart review performed to compare short term outcomes between both the groups. Patients undergoing LAAO with Watchman 2.5 or epicardial approach with Lariat were excluded. A total of 326 patients underwent LAAO including 230 Watchman FLX and 96 with Amulet. There were no differences in all available baseline characteristics including mean age (76.3 ±8.3 years), women (46%), mean CHA2DS2-VASc score, and HAS-BLED score (Table). The procedural time (74 ± 32.5 vs. 66 ± 19.5 mins; P=0.02) and contrast volume (54 ± 27.4 vs. 39.9 ± 19.6 P =<0.01) were significantly higher for Amulet as compared to Watchman FLX. No difference in procedural outcomes (Acute success, adverse events and residual leak) noted in immediate post procedure period and at 45 day follow-up. In a single-center, real world experience, LAAO with Amulet was associated with higher procedure time and contrast utilization with no difference in short term procedural outcome.

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.