Efficacy and Safety of Left Atrial Appendage Closure With WATCHMAN in Japanese Nonvalvular Atrial Fibrillation Patients - Final 2-Year Follow-up Outcome Data From the SALUTE Trial

Safety and feasibility of atrial fibrillation ablation after left atrial appendage closure: A single-center experience of the left atrial appendage closure first strategy

Background

Patients with atrial fibrillation (AF) who are not suitable for long-term anticoagulant therapy undergo percutaneous left atrial appendage closure (LAAC). The safety and feasibility of left atrial catheter ablation (CA) procedures after LAAC remain unclear. This study aimed to clarify the feasibility and safety of CA after LAAC, including in the early phase within 180 days.

Methods

Characteristics and clinical outcomes of 46 patients with AF who had undergone both CA and LAAC within 2 years (mean age, 72 years; 29 men) were compared between those who had undergone CA-first (31 patients) and LAAC-first (15 patients).

Results

The mean CHA₂DS₂-VASc and HAS-BLED scores were 4.8 and 3.3 points, respectively. The LAAC-first strategy was often used in patients with prior major bleeding and LAA thrombosis or sludge. In the LAAC-first group, the mean duration between both procedures was 212 days, and all LAAC-first patients, including seven patients in the early phase, could undergo CA without LAAC device-related complications; moreover, no cardiovascular adverse events were reported after both procedures (mean periods: 420 days). After CA post-LAAC, no device-related adverse events (device-related thrombosis, new peri-device leak appearance, peri-device leak increase, or device dislodgement) were observed, whereas, after LAAC post-CA, 3 new peri-device leak appearance events and 1 peri-device leak increase event were observed, especially patients who underwent LAAC in the early phase post-CA.

Conclusion

Based on single-center experience, left atrial CA in the presence of an LAAC device implanted including the early phase was safe and feasible.

Comparative Data of Procedural and Midterm Outcomes in Patients Who Underwent Percutaneous Left Atrial Appendage Closure Between the WATCHMAN FLX and WATCHMAN 2.5 Devices - Insight From the OCEAN-LAAC Registry

BACKGROUND

Limited data are available regarding clinical outcomes after percutaneous left atrial appendage closure using WATCHMAN FLX (WM-FLX) and WATCHMAN-2.5 (WM2.5) devices in Asian patients.

METHODS AND RESULTS

Data of 1,464 consecutive patients (WM-FLX, n=909; WM2.5, n=555) were extracted from a Japanese multicenter registry, and clinical data were compared between the 2 groups. No in-hospital deaths, periprocedural stroke, or device embolization occurred. Procedural success was significantly higher in the WM-FLX than WM2.5 group (95.8% vs. 91.9%; P=0.002) owing to the lower incidence of periprocedural pericardial effusion (0.55% vs. 1.8%; P=0.021). No significant differences in all-cause death, postprocedural stroke, and device-related thrombus were observed between the 2 groups. However, the cumulative bleeding rate at 1 year was substantially lower in the WM-FLX group (7.8% vs. 16.4%; P<0.001). Landmark analysis of bleeding events highlighted lower bleeding rates in the WM-FLX than WM2.5 group within the first 6 months (6.4% vs. 14.8%; P<0.001), with comparable bleeding rates over the 6- to 12-month period (1.5% vs. 3.2%, respectively; P=0.065).

CONCLUSIONS

This study demonstrated higher early safety and lower 1-year bleeding rates in the WM-FLX than WM2.5 group. The lower bleeding events with WM-FLX are likely due to multiple factors other than purely difference in devices, such as postprocedural drug regimen.

Initial results of transcatheter modification of left atrial appendage by obliteration with device in patients with nonvalvular atrial fibrillation: Real-world data from the TERMINATOR registry

BACKGROUND

Percutaneous left atrial appendage closure (LAAC) has increased for those who need alternative to long-term anticoagulation with non-valvular atrial fibrillation (NVAF).

METHODS AND RESULTS

From September 2019, after initiating WATCHMAN (Boston Scientific, Maple Grove, MN, USA) device implantation, we established Transcatheter Modification of Left Atrial Appendage by Obliteration with Device in Patients from the NVAF (TERMINATOR) registry. Utilizing 729 patients' data until January 2022, we analyzed percutaneous LAAC data regarding this real-world multicenter prospective registry. A total of 729 patients were enrolled. Average age was 74.9 years and 28.5 % were female. Paroxysmal AF was 37.9 % with average CHADS2 3.2, CHA2DS2-VASc 4.7, and HAS-BLED score of 3.4. WATCHMAN implantation was successful in 99.0 %. All-cause deaths were 3.2 %, and 1.2 % cardiovascular or unexplained deaths occurred during follow-up [median 222, interquartile range (IQR: 93-464) days]. Stroke occurred in 2.2 %, and the composite endpoint which included cardiovascular or unexplained death, stroke, and systemic embolism were counted as 3.4 % [median 221, (IQR: 93-464) days]. Major bleeding defined as BARC type 3 or 5 was seen in 3.7 %, and there was 8.6 % of all bleeding events in total [median 219, (IQR: 93-464) days].

CONCLUSIONS

These preliminary data demonstrated percutaneous LAAC with WATCHMAN device might have a potential to reduce stroke and bleeding events for patients with NVAF. Further investigation is mandatory to confirm the long-term results of this strategy using this transcatheter local therapy instead of life-long systemic anticoagulation.

Clinical significance of gastrointestinal bleeding history in patients who undergo left atrial appendage closure

Background and Aim

Anticoagulant users with nonvalvular atrial fibrillation (NVAF) sometimes suffer from gastrointestinal bleeding (GIB) and have difficulty continuing the medication. Left atrial appendage closure (LAAC) has been developed for such situations. We aimed to clarify the clinical significance of a history of GIB in comparison to other factors in patients who had undergone LAAC.

Methods

From October 2019 to September 2023, patients with NVAF who underwent LAAC at our hospital were enrolled. We investigated the percentage of patients with a history of GIB who underwent LAAC and compared the incidence of post-LAAC bleeding in these patients compared to those with other factors.

Results

A total of 45 patients were included. There were 19 patients (42%) with a history of GIB who underwent LAAC. In a Kaplan-Meier analysis, the cumulative incidence of bleeding complications after LAAC was significantly higher in patients with a history of GIB in comparison to patients with other factors. There were eight cases of post-LAAC bleeding in total, and seven cases had GIB.

Conclusions

We need to recognize that GIB is a significant complication in patients who undergo LAAC. The management of GIB by gastroenterologists is essential to the success of LAAC.

Antithrombotic Regimen After Percutaneous Left Atrial Appendage Closure - A Real-World Study

BACKGROUND

Antithrombotic therapy after left atrial appendage closure (LAAC) in patients at high risk of bleeding remains controversial. We present real-world clinical outcomes of LAAC.

METHODS AND RESULTS

Data from 74 consecutive patients who received LAAC therapy between January 2020 and June 2022 were analyzed. Patients received 1 of 3 antithrombotic therapies according to the bleeding risk category or clinical event. Regimen 1 was based on a prior study, regimen 2 comprised a lower antiplatelet drug dose without dual antiplatelet therapy, and regimen 3 was antiplatelet drug administration for as long as possible to patients with uncontrollable bleeding who were required to stop anticoagulant drugs. Overall, 73 (98.6%) procedures were successful. Of them, 16 (21.9%) patients were selected for regimen 1, 46 (63.0%) for regimen 2, and 11 (15.1%) for regimen 3. Device-related thrombosis (13% vs. 0% vs. 0%, P=0.0257) only occurred with regimen 1. There was no difference in major bleeding event rates (6% vs. 2% vs. 9%, P=0.53).

CONCLUSIONS

The post-LAAC antithrombotic regimen was modified without major concerns.

Mid-Term Feasibility of Percutaneous Left Atrial Appendage Occlusion in Elderly Patients with Non-Valvular Atrial Fibrillation

BACKGROUND

Percutaneous left atrial appendage occlusion (LAAO) therapy using the WATCHMAN system has been introduced to prevent thrombosis and minimize the use of anticoagulants in patients with non-valvular atrial fibrillation. Given the high risk of bleeding and stroke in elderly patients, these patients would be good candidates for this therapy. However, the efficacy and feasibility of LAAO therapy in elderly patients remains uncertain.

METHODS

Consecutive patients who underwent LAAO therapy using the WATCHMAN system in a large academic center between June 2020 and March 2023 were included. The safety and efficacy of LAAO therapy during the 1-year observation period in patients aged ≥85 years old were compared with those in the younger cohort.

RESULTS

A total of 188 patients (78.4 ± 6.9 years old, 133 male patients) were included. 34 patients were ≥85 years old, 96 were between 75 and 84 years old, and 58 were <75 years old. The elderly group had a higher CHA2DS2-VASc score and were at greater risk of falling-related bleeding compared with the younger cohort. The device implantations were successful in all patients except for one. During the 1-year observation period, one patient had a peri-device leak >5 mm and there were 6 device-related cases of thrombosis, whose incidence was not significantly different between the groups (p = 0.98). The cumulative incidences of bleeding and thrombotic events in the elderly group were as low as in the younger cohort (p > 0.05 for both). Most anticoagulants were terminated regardless of age.

CONCLUSION

The mid-term feasibility and efficacy of percutaneous LAAO therapy using the WATCHMAN system in elderly patients aged ≥85 years were as acceptable as in the younger cohort.

Foam-based Left Atrial Appendage Closure (CLAAS) Device: Evaluation in a Chronic Canine Model

Background

The Conformal Left Atrial Appendage System (CLAAS) is a transcatheter implant designed to occlude the left atrial appendage to prevent stroke in patients with nonvalvular atrial fibrillation. The implant incorporates a novel polyurethane polycarbonate-urea foam matrix to enhance device performance. The objective of this study was to characterize the thrombogenicity, sealing, implant integrity, local tissue response, and systemic toxicity of the implant in a healthy canine model.

Methods

Devices were evaluated in a chronic canine model using echocardiographic and fluoroscopic guidance (n = 8). Postprocedural echocardiographic evaluation was performed at case completion and at 2, 45, 90, and 150 days. Animals were sacrificed at 90 (n = 4) and 150 (n = 4) days. Necropsy included gross, x-ray, and histologic examination.

Results

CLAAS implants were implanted in all animals successfully on the basis of fluoroscopic, intracardiac echo, and transthoracic echo criteria. Although 2 animals were noted to have leaks (1 at implantation and 1 at day 90 post procedure before sacrifice), both were of <5 mm. All left atrial appendages were completely sealed on gross examination. No device-related thrombus, pericardial effusion, or evidence of distal organ emboli was observed. All implants maintained their structural integrity and were well integrated within the tissue. There was no histologic evidence of toxicity noted in the downstream organs or tissues.

Conclusions

The CLAAS implant can be deployed providing a good seal for up to 150 days without signs of local or systemic toxicity in a canine model.

Percutaneous Left Atrial Appendage Closure in a Patient with Diffuse Alveolar Hemorrhaging Associated with Anticoagulant Therapy and Atrial Fibrillation

Diffuse alveolar hemorrhaging (DAH) due to oral anticoagulation (OAC) is a life-threatening condition that leads to severe respiratory failure. There is a clinical dilemma in that OAC-induced DAH often forces the discontinuation of OAC therapy and the administration of high-dose corticosteroids, which increases the risk of stroke and cardiovascular events. We herein report the first case of OAC-induced DAH and atrial fibrillation (AF) in a patient who completely discontinued OAC therapy and high-dose corticosteroids after experiencing percutaneous left atrial appendage (LAA) occlusion. This case suggests that percutaneous LAA closure may aid in the management of OAC-induced DAH and AF.

Comparison in Short-Term Safety and Efficacy between New-Generation WATCHMAN FLX and Conventional WATCHMAN 2.5 for Percutaneous Left Atrial Appendage Closure

Background: Percutaneous left atrial appendage closure using the WATCHMAN system, to prevent thrombosis and minimize anti-coagulant use in patients with non-valvular atrial fibrillation, has recently been introduced. The safety and efficacy of new-generation WATCHMAN FLX, as compared to conventional WATCHMAN 2.5, remain unknown. Methods: Consecutive patients who received percutaneous left atrial appendage closure using the WATCHMAN system in our institute, between June 2020 and December 2021, were retrospectively analyzed. Safety and efficacy during the 45-day observational period were compared between the two devices. Results: A total of 93 patients (73.0 ± 7.3 years old, 63 men) who received WATCHMAN FLX (n = 44) or WATCHMAN 2.5 (n = 49) were included. The device implant success rate was 100% in the FLX device group and 98% in the 2.5 device group. There were no procedure-related complications in the FLX group, and one non-relevant pericardial effusion in the 2.5 device group. During the 45-day observational period, there were no procedure-related adverse events. No patients in the FLX group had a peri-device leak >3 mm, whereas two patients in the 2.5 device group had a peri-device leak >3 mm. Anti-coagulants could be terminated in most of the patients (85% versus 88%; p = 0.68). Conclusions: Percutaneous left atrial appendage closure using new-generation WATCHMAN FLX seemed to be as safe and effective as conventional WATCHMAN 2.5 during the short-term observational period.

Effectiveness and safety of transcatheter left atrial appendage closure

Atrial fibrillation (AF) is responsible for cardiogenic stroke. Since left atrial appendage (LAA) is a cause of most of cardiac thrombus, LAA closure is an emerging novel stroke prevention procedure for patients with AF alternative to anticoagulation. WATCHMAN LAA Closure device (Boston Scientific, Marlborough, MA, USA) is the only approved device in the USA and Japan. The device is indicated in high bleeding risk and high stroke risk non-valvular AF patients. Cardiac tamponade, stroke, and device embolization are typical procedural complications. Procedural complication rate is reduced with implanters' experience and matured procedure steps. Several randomized trials demonstrated procedure safety and efficacy of the device. The device resulted in similar thromboembolic event rates but significantly reduced bleeding events compared to anticoagulants. After the procedure, optimal post procedural antithrombotic drug regimen has not been fully investigated. Also, device-related thrombosis can be a new issue. Modification of the device can improve issues, but not fully solve it. Tailor made treatment based on the individual risk by heart team communication with neurologists is essential to treat patients.