Cardiac Damage in Degenerative Mitral Regurgitation Treated With Transcatheter Mitral Edge-to-Edge Repair.

BACKGROUND: The extent of cardiac damage and its association with clinical outcomes in patients undergoing transcatheter edge-to-edge repair (TEER) for degenerative mitral regurgitation remains unclear. This study was aimed to investigate cardiac damage in patients with degenerative mitral regurgitation treated with TEER and its association with outcomes. METHODS: We analyzed patients with degenerative mitral regurgitation treated with TEER in the Optimized Catheter Valvular Intervention-Mitral registry, which is a prospective, multicenter observational data collection in Japan. The study subjects were classified according to the extent of cardiac damage at baseline: no extravalvular cardiac damage (stage 0), mild left ventricular or left atrial damage (stage 1), moderate left ventricular or left atrial damage (stage 2), or right heart damage (stage 3). Two-year mortality after TEER was compared using Kaplan-Meier analysis. RESULTS: Out of 579 study participants, 8 (1.4%) were classified as stage 0, 76 (13.1%) as stage 1, 319 (55.1%) as stage 2, and 176 (30.4%) as stage 3. Two-year survival was 100% in stage 0, 89.5% in stage 1, 78.9% in stage 2, and 75.3% in stage 3 (P=0.013). Compared with stage 0 to 1, stage 2 (hazard ratio, 3.34 [95% CI, 1.03-10.81]; P=0.044) and stage 3 (hazard ratio, 4.51 [95% CI, 1.37-14.85]; P=0.013) were associated with increased risk of 2-year mortality after TEER. Significant reductions in heart failure rehospitalization rate and New York Heart Association functional scale were observed following TEER (both, P<0.001), irrespective of the stage of cardiac damage. CONCLUSIONS: Advanced cardiac damage is associated with an increased risk of mortality in patients undergoing TEER for degenerative mitral regurgitation. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: UMIN000023653.

Comparison of left atrial appendage measurements between conventional transesophageal echocardiography and "Virtual TEE" reconstructed from computed tomography for pre-procedural planning of device closure.

For pre-procedural planning of left atrial appendage (LAA) closure, sizing is crucial. Although transesophageal echocardiography (TEE) is a standard modality, cardiac computed tomography (CT) is also widely used. The virtual TEE (V-TEE) that our group developed enables us to reconstruct images similar to TEE images from CT images. The software should be helpful to understand and plan the procedure strategy. Accordingly, we investigated the utility of V-TEE. Sixty-six patients at 4 participating sites who completed both CT and TEE prior to LAA closure were included. The LAA diameter at the landing zone (LZ) for WATCHMAN™ device implantation was statistically compared at 0°, 45°, 90°, and 135° between V-TEE and TEE. Among 66 cases, only 3 cases were excluded due to poor imaging quality, and 63 cases were analyzed. The device LZ diameters based on V-TEE were strongly correlated with those based on TEE, despite the significantly greater diameter based on V-TEE with mean differences of 2.4 to 3.0 mm (all of them: P < 0.001). The discordances (V-TEE/TEE ratio) at most angles were significantly larger in the elliptical LAAs. V-TEE provides a valuable method for the evaluation of the LAA diameters. V-TEE-based measurements were larger than conventional TEE-based measurements, especially in cases of elliptical LAAs. The assessment by V-TEE has the potential benefit of ensuring proper device sizing regardless of the LAA morphology.

Predictive Factors of Cardiac Mortality Following TEER in Patients with Secondary Mitral Regurgitation.

Background: Transcatheter edge-to-edge mitral valve repair (TEER) has emerged as a viable approach to addressing substantial secondary mitral regurgitation. In the contemporary landscape where ultimate heart failure-specific therapies, such as cardiac replacement modalities, are available, prognosticating a high-risk cohort susceptible to early cardiac mortality post-TEER is pivotal for formulating an effective therapeutic regimen. Methods: Our study encompassed individuals with secondary mitral regurgitation and chronic heart failure enlisted in the multi-center (Optimized CathEter vAlvular iNtervention (OCEAN)-Mitral registry. We conducted an assessment of baseline variables associated with cardiac death within one year following TEER. Results: Amongst the 1517 patients (median age: 78 years, 899 males), 101 experienced cardiac mortality during the 1-year observation period after undergoing TEER. Notably, a history of heart failure-related admissions within the preceding year, utilization of intravenous inotropes, and elevated plasma B-type natriuretic peptide levels emerged as independent prognosticators for the primary outcome (p < 0.05 for all). Subsequently, we devised a novel risk-scoring system encompassing these variables, which significantly stratified the cumulative incidence of the 1-year primary outcome (16%, 8%, and 4%, p < 0.001). Conclusions: Our study culminated in the development of a new risk-scoring system aimed at predicting 1-year cardiac mortality post-TEER.

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.

Short-Term Outcomes Following Transcatheter Edge-to-Edge Repair: Insights From the OCEAN-Mitral Registry.

Background: Transcatheter edge-to-edge repair (TEER) is a less invasive treatment for patients with mitral regurgitation (MR). Limited safety and efficacy data of TEER with MitraClip, including the fourth-generation (G4) system, in a large cohort, are available. Objectives: This study aimed to summarize the initial experience of the TEER system in patients with MR from a large registry in Japan. Methods: The OCEAN (Optimized CathEter vAlvular iNtervention)-Mitral Registry is an ongoing, prospective, investigator-initiated, multicenter, observational registry for patients with primary and secondary MR undergoing transcatheter mitral valve therapies. A total of 21 centers participated in the registry. Patients undergoing TEER were enrolled, and their characteristics, procedural details, and clinical outcomes were recorded. Results: In total, 2,150 patients including 1,605 patients (75.0%) with secondary MR, were enrolled between April 2018 and June 2021. The median age was 80 years, and 43.7% were women. The median device and fluoroscopy times were 60 and 26 minutes, respectively. Those with the G4 system (618/2,150 [28.7%]) were significantly shorter than those with the second generation (G2) system (1,532/2,150 [71.3%]). Overall, 94.6% met acute procedural success without significant differences between the 2 systems (G2 94.7% vs G4 94.6%; P = 0.961). Conclusions: The OCEAN-Mitral registry has demonstrated the short-term outcomes of TEER systems, including the G4 system, in symptomatic patients with primary and secondary MR. The acute procedural success rate in the G2 system was excellent, and that in the G4 system was expected to improve with the multidisciplinary heart valve team approach. (Japanese Registry study of valvular heart diseases treatment and prognosis; UMIN000023653).

One-Year Outcomes and Their Relationship to Residual Mitral Regurgitation After Transcatheter Edge-to-Edge Repair With MitraClip Device: Insights From the OCEAN-Mitral Registry.

Background Limited data are available about clinical outcomes and residual mitral regurgitation (MR) after transcatheter edge-to-edge repair in the large Asian-Pacific cohort. Methods and Results From the Optimized Catheter Valvular Intervention (OCEAN-Mitral) registry, a total of 2150 patients (primary cause of 34.6%) undergoing transcatheter edge-to-edge repair were analyzed and classified into 3 groups according to the residual MR severity at discharge: MR 0+/1+, 2+, and 3+/4+. The mortality and heart failure hospitalization rates at 1 year were 12.3% and 15.0%, respectively. Both MR and symptomatic improvement were sustained at 1 year with MR ≤2+ in 94.1% of patients and New York Heart Association functional class I/II in 95.0% of patients. Compared with residual MR 0+/1+ (20.4%) at discharge, both residual MR 2+ (30.2%; P < 0.001) and 3+/4+ (32.4%; P = 0.007) were associated with the higher incidence of death or heart failure hospitalization (adjusted hazard ratio [HR], 1.59; P < 0.001, and adjusted HR, 1.73; P = 0.008). New York Heart Association class III/IV at 1 year was more common in the MR 3+/4+ group (20.0%) than in the MR 0+/1+ (4.6%; P < 0.001) and MR 2+ (6.4%; P < 0.001) groups, and the proportion of New York Heart Association class I is significantly higher in the MR 1+ group (57.8%) than in the MR 2+ group (48.3%; P = 0.02). Conclusions The OCEAN-Mitral registry demonstrated favorable clinical outcomes and sustained MR reduction at 1 year in patients undergoing transcatheter edge-to-edge repair. Both residual MR 2+ and 3+/4+ after transcatheter edge-to-edge repair at discharge were associated with worse clinical outcomes compared with residual MR 0+/1+. Registration Information https://upload.umin.ac.jp. Identifier: UMIN000023653.

Impact of Gender on Mortality After Transcatheter Edge-to-Edge Repair for Functional Mitral Regurgitation.

Recent studies suggested short-term mortality after transcatheter edge-to-edge repair (TEER) was comparable between men and women. However, the gender-specific prognostic difference in the long-term follow-up after TEER is still unknown. To evaluate the impact of gender on long-term mortality after TEER for functional mitral regurgitation (FMR) using multicenter registry data. We retrospectively analyzed 1,233 patients (male 60.3%) who underwent TEER for FMR at 24 centers. The impact of gender on all-cause death and hospitalization for heart failure (HF) after TEER was evaluated using multivariate regression analysis and propensity score (PS) matching methods. During the 2-year follow-up, 207 all-cause death and 263 hospitalizations for HF were observed after TEER for FMR. Men had a significantly higher incidence of all-cause death than women (18.6% vs 14.1%, log-rank p = 0.03). After adjustment by multivariate Cox regression and PS matching, the male gender was significantly associated with a higher incidence of all-cause mortality after TEER than the female gender (hazard ratio 2.11, 95% confidence interval 1.42 to 3.14 in multivariate Cox regression; hazard ratio 1.89, 95% confidence interval 1.03 to 3.48 in PS matching). The gender-specific prognostic difference was even more pronounced after 1-year of TEER. On the contrary, there was no gender-related difference in hospitalization for HF after TEER. In conclusion, women with FMR had a better prognosis after TEER than men, whereas this was not observed in hospitalization for HF. This result might indicate that women with FMR are more likely to benefit from TEER.

[Detection of secondary atrial fibrillation following percutaneous foramen ovale closure for cryptogenic stroke using an insertable cardiac monitor: a case report].

A 61-year-old man presented with transient dysarthria and left upper extremity numbness. Head MRI showed an acute infarct in the left temporal lobe and multiple old infarcts in the bilateral cortices. A transesophageal echocardiogram revealed a patent foramen ovale with a large shunt. No deep vein thrombosis was found. He suffered a recurrent cerebral infarction while taking antiplatelet therapy. An insertable cardiac monitor was implanted on the 41st day, and the antiplatelet treatment was changed to warfarin. The insertable cardiac monitor did not detect atrial fibrillation, even when the patient had a recurrent transient ischemic attack on the 57th day under warfarin therapy. The patient underwent percutaneous foramen ovale closure on the 63rd day. On postoperative days 18-25, an insertable cardiac monitor detected brief atrial fibrillation, and he took rivaroxaban for three months. Atrial fibrillation may occur secondary to percutaneous patent foramen ovale closure for cryptogenic stroke. The insertable cardiac monitor may help diagnose the pathogenesis of secondary atrial fibrillation and determine the optimal antithrombotic therapy.

Percutaneous repair of systemic atrioventricular valve regurgitation with the MitraClip-NT system in congenitally corrected transposition of great arteries.

In a patient with congenitally corrected transposition of the great arteries, dilatation of the atrioventricular valve annulus related to worsening of systemic ventricular function, which worsened systemic atrioventricular valve (SAVV) functional regurgitation. In this article, we report a case of successful transcatheter treatment with MitraClip (Abbott Vascular, Santa Clara, CA, USA) in a 68-year-old female patient with congenitally corrected transposition of the great arteries and severe SAVV failure using imaging modalities. The patient had been hospitalized four times within 8 months, receiving optimal medical therapy for severe SAVV regurgitation and systemic ventricular failure. In this patient, the risk associated with surgery was considered extremely high owing to severe heart failure and liver cirrhosis. We positioned two clips appropriately, side by side, in between the anterior and septal leaflets, guided by computed tomography and three-dimensional echocardiography. The procedure resulted in optimal post-procedural reduction of regurgitation without stenosis, with a good clinical outcome noted at 2-year follow-up. Learning objective: Since surgery for adult congenital heart disease is linked to high risk, we seek less invasive treatment for such patients. In patients with congenital heart disease and severe valve regurgitation, the use of MitraClip (Abbott Vascular, Santa Clara, CA, USA) could be a feasible option for select cases.

Edoxaban vs. Vitamin K Antagonist for Atrial Fibrillation After Transcatheter Aortic Valve Replacement in Japanese Patients　- A Subanalysis of the ENVISAGE-TAVI AF Trial.

BACKGROUND: Japanese patients undergoing transcatheter aortic valve replacement (TAVR) are often female and have a small body size, potentially impacting bleeding risk with antithrombotic therapy. Outcomes of direct oral anticoagulant use in these patients with atrial fibrillation (AF) need to be clarified.Methods and Results: This prespecified analysis included Japanese patients from ENVISAGE-TAVI AF, a prospective, randomized, open-label, adjudicator-masked trial that compared treatment with edoxaban and vitamin K antagonists (VKAs) in patients with AF after TAVR. The primary efficacy and safety outcomes were net adverse clinical events (NACE; composite of all-cause death, myocardial infarction, ischemic stroke, systemic embolic event, valve thrombosis, and International Society on Thrombosis and Haemostasis [ISTH]-defined major bleeding) and ISTH-defined major bleeding, respectively. Intention-to-treat (ITT) and on-treatment analyses were performed. Overall, 159 Japanese patients were enrolled (edoxaban group: 82, VKA group: 77) and followed for on average 483 days. Mean patient age was 83.8 years; 52.2% were female. In the ITT analysis, NACE rates were 10.9%/year with edoxaban and 12.5%/year with VKA (hazard ratio [HR], 0.85; 95% confidence interval [CI], 0.38-1.90); major bleeding occurred in 8.9%/year and 7.3%/year, respectively (HR, 1.17; 95% CI, 0.45-3.05). In edoxaban- and VKA-treated patients, rates of ischemic stroke were 1.8%/year and 1.0%/year, respectively; fatal bleeding rates were 0.9%/year and 2.0 %/year. On-treatment results were similar to ITT. CONCLUSIONS: In Japanese patients with AF after successful TAVR, edoxaban and VKA treatment have similar safety and efficacy profiles.

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.

The rare case of a MitraClip device migrating into the left ventricular apex.

A 79-year-old man with atrial fibrillation and heart failure due to grade 4 + mitral valve regurgitation after coronary artery bypass underwent the MitraClip procedure using two clips. Three days after the procedure, chest radiographs indicated migration of one of the two clips into the left ventricle. He suffered from 3 + recurrent mitral regurgitation, tricuspid valve regurgitation. The echocardiogram and computed tomography scans indicated migration of the clip into the left ventricular apex; he underwent mitral valve replacement, removal of the migrated clip to prevent embolism, left atrial appendage closure, and tricuspid valve ring-annuloplasty. In the postoperative acute phase, embolism by detached and lost MitraClip device is possible, which can be difficult to remove.

Sex-Related Differences in Cardiac Remodeling and Reverse Remodeling After Transcatheter Aortic Valve Implantation in Patients with Severe Aortic Stenosis in a Japanese Population.

Left ventricular (LV) remodeling with aortic stenosis (AS) appears to differ according to sex, but reverse remodeling after transcatheter aortic valve implantation (TAVI) has not been elucidated in a Japanese population. This study aims to determine whether any sex-related differences in LV or reverse remodeling after TAVI exist in the context of severe AS.Of 208 patients who received TAVI for severe AS in our institution, 100 (men, 42; mean age, 83.0 ± 4.9 years) underwent transthoracic echocardiography before and 3 months after TAVI. Despite similar valvular gradients, women with severe AS had lower indexed LV mass (LVMi) than did men (152.3 ± 35.4 versus 173.2 ± 44.6 g/m2, P = 0.005), with smaller indexed LV end-diastolic (LVEDVi) (50.2 ± 13.3 versus 61.4 ± 20.7 mL/m2, P = 0.001) and end-systolic (LVESVi; 17.9 ± 8.7 versus 24.3 ± 13.8 mL/m2, P = 0.006) volumes. After TAVI, women (-6.0% ± 14.4%) had higher reduction in the rate of change of relative wall thickness (RWT) than did men (4.4% ± 19.0%, P = 0.003). Men (-8.9% ± 3.9%) had higher reduction in the rate of change of LVEDVi than did women (1.5% ± 3.3%, P = 0.045). Incidence of LV reverse remodeling defined as a reduction in LVESV of >15% was significantly higher in men (50%) than in women (26%, P = 0.013).In addition to sex differences in the pattern of LV remodeling with AS, reverse LV remodeling after TAVI also differed between sexes.

Structural heart intervention for prevention of embolic and hemorrhagic stroke: The new field of neurocardiology.

Cardiogenic stroke (CS), characteristic causes of which include atrial fibrillation (AF) and right-to-left shunting due to a patent foramen ovale (PFO), has a well-known tendency to be associated with a more extensive ischemic area. This may result in severe neurological damage, and require strict life-long antithrombotic therapy. However, the fact that some patients have problems complying with the requirement for extended oral antithrombotic treatment has motivated the development of alternative approaches for stroke prevention. Heart structures such as the left atrial appendage (LAA) and PFO are potential targets for stroke prevention by way of device implantation. Several large prospective randomized clinical trials have demonstrated efficacy and safety of devices dedicated to this purpose. Percutaneous LAA occlusion for patients with non-valvular AF resulted in similar embolic event rates but significantly reduced bleeding events than did therapy with warfarin. Furthermore, PFO closure significantly reduced the frequency of recurrent embolic stroke relative to oral antithrombotic treatment. Current unsolved problems remaining in the application of these two strategies can be identified as the lack of standardized regimens for post-procedural antithrombotic therapy, ambiguity of determining the indications therefore, and the problem of device-related thrombus, which need to be investigated in depth in future. Cost-benefit analysis in comparison with standard medication is also required for each instance. A heart-brain multidisciplinary team approach, mandated to start such structural heart interventions, will become the future standard unit of personnel for stroke management, which promises to usher in the new field of neurocardiology.

First experience of the usage of a GORE CARDIOFORM Septal Occluder device for treatment of a significant residual commissural mitral regurgitation jet following a MitraClip procedure.

The MitraClip (Abbott Vascular, Santa Clara, CA) procedure has emerged as a safe and effective treatment option for treatment of selected patients with severe mitral regurgitation (MR) who are at high risk for surgery. Effective reduction of MR is important to ensure an optimal clinical outcome. We present here the first case report of a significant commissural leak after a MitraClip procedure treated with a GORE CARDIOFORM Septal Occluder device (WL Gore & Associates, Flagstaff, AZ). CASE REPORT: An 81-year-old male presented with symptomatic recurrent MR following a MitraClip procedure using two clips. After adding another clip, there was still a residual jet medially. We plugged the gap using 12-mm AMPLATZER Muscular VSD Occluder device (St. Jude Medical, Minneapolis, MN). MR was reduced but hemolysis occurred. We retrieved the VSD Occluder device to improve hemolysis, but the MR jet worsened to severe, so we placed a 30-mm GORE CARDIOFORM Septal Occluder device. The device was stable, the MR jet was reduced dramatically, and hemolysis was not observed. Materials of these devices are mesh fabric made from nitinol and polyester in a VSD Occluder device and expanded polytetrafluoroethylene in GORE CARDIOFORM Septal Occluder device. The difference between device materials affects flow pattern of residual jet and hemolysis. In conclusion, the patient's risk for hemolysis is potentially affected by the occluder or plug material. GORE CARDIOFORM is a feasible choice to reduce the risk of hemolysis in a selected patient.

Impact of Forward Stroke Volume Response on Clinical and Structural Outcomes After Percutaneous Mitral Valve Repair With MitraClip.

BACKGROUND: An increase of systolic forward flow was frequently observed after successful MitraClip implantation in patients with significant mitral regurgitation. However, the impact of systolic forward flow improvement on post-MitraClip outcomes remains unknown. METHODS AND RESULTS: Study population included 160 patients who underwent successful MitraClip implantation. The systolic forward flow was noninvasively calculated as the forward stroke volume (FSV) at baseline before the MitraClip procedure and before discharge with pulse-wave Doppler using transthoracic echocardiography. The optimal threshold of discharge/baseline FSV ratio for 3-year all-cause death was assessed. The best cutoff ratio was 1.09 (9% FSV increase from baseline, P=0.006). The FSV responders were defined as those with >9% increase of FSV from baseline (n=93). From discharge to 12-month follow-up, a significant reduction of LV end-diastolic and end-systolic volumes was observed in the responders, whereas no significant change was observed in the nonresponders. Furthermore, the proportion of New York Heart Association functional class III/IV was significantly lower in the responders at 12 months (2.9% versus 14.6%; P=0.03). Among patients with estimated glomerular filtration rate <60 mL/min per 1.73 m2, estimated glomerular filtration rate was significantly improved at 12 months only in the responders. All-cause mortality at 3 years was significantly lower in the responders than in the nonresponders (17.6% versus 42.3%; P=0.002). Multivariable logistic analysis identified higher baseline FSV, less mitral regurgitation severity, and functional mitral regurgitation as independent predictors of the nonresponders. CONCLUSIONS: FSV increase after MitraClip implantation was associated with more favorable clinical and anatomic outcomes. Severity and pathogenesis of mitral regurgitation and pre-MitraClip FSV predicted postprocedural FSV response.

Incidence, Characteristics, and Clinical Course of Device-Related Thrombus After Watchman Left Atrial Appendage Occlusion Device Implantation in Atrial Fibrillation Patients.

OBJECTIVES: This study investigated characteristics and clinical impact of device-related thrombus formation after Watchman device implantation in atrial fibrillation (AF) patients. BACKGROUND: Left atrial appendage occlusion using the Watchman device is an effective alternative to anticoagulation for stroke prevention in AF patients. However, device-related thrombus formation remains an important concern after Watchman implantation. METHODS: From 2006 to 2014, 119 consecutive AF patients underwent Watchman implantation. Transesophageal echocardiographic (TEE) follow-up was scheduled at 45 days, at 6 months, and at 12 months after the procedure. The incidence, characteristics, and clinical course of device-related thrombus formation detected by TEE were assessed. RESULTS: Follow-up TEE identified thrombus formation on the Watchman device in 4 patients (3.4%). The prevalence of chronic AF was 100% in patients with thrombus, which was higher than that for patients without thrombus (40.0%). Deployed device size was numerically larger in patients with thrombus (29.3 ± 3.8 mm vs. 25.7 ± 3.2 mm, respectively). All patients with thrombus discontinued any of the anticoagulant/antiplatelet therapy which was required under the study protocol. After restarting or continuing warfarin and aspirin therapy, complete resolution of the thrombus was achieved in all patients at subsequent follow-up TEE. Warfarin therapy was discontinued within 6 months for all cases, and there was no thrombus recurrence. The mean follow-up duration was 1,456 ± 546 days, with no death, stroke, or systemic embolization events in patients with thrombus. CONCLUSIONS: AF burden, device size, and anticoagulant/antiplatelet regimens can be associated with device-related thrombus after Watchman device implantation. Short-term warfarin therapy was effective, and the clinical outcomes were favorable.