Peridevice Leak After Transcatheter Left Atrial Appendage Occlusion: An Analysis of the Amulet IDE Trial

BackgroundPeridevice leak (PDL) is a limitation of left atrial appendage occlusion.ObjectivesThe aim of this study was to assess the incidence of and outcomes associated with PDL in the Amulet IDE (AMPLATZER? Amulet? LAA Occluder Trial) randomized controlled trial.MethodsPatients with atrial fibrillation at increased stroke risk were randomly assigned to undergo either Amulet (dual occlusive mechanism) or Watchman 2.5 (single occlusive mechanism) device implantation. Transesophageal echocardiography was performed at 45 days and 12 months postprocedure. Clinically significant PDL was defined as ≥3 mm. The primary endpoint was ischemic stroke or systemic embolism, and the secondary endpoint was stroke, systemic embolism, or cardiovascular death. The Kaplan-Meier method was used to estimate 18-month cumulative event rates landmarked at day 45 postprocedure.ResultsA total of 1,593 patients underwent successful left atrial appendage occlusion and had an evaluable transesophageal echocardiographic studies at 45 days. The dual–occlusive mechanism device provided superior closure (defined as leak <3 mm) compared with the single–occlusive mechanism device at 45 days (88.9% vs 74.1%; P < 0.01) and 12 months (90.5% vs. 78.3%; P < 0.01). Through 18 months, PDL was associated with a higher, but not statistically significant, risk for the primary endpoint (3.6% vs 1.8%; adjusted HR: 1.98; 95% CI: 0.93-4.19; P = 0.07) and a statistically significantly higher risk for the secondary endpoint (8.1% vs. 4.7%; adjusted HR: 1.66; 95% CI: 1.02-2.69; P = 0.04).ConclusionsThe dual–occlusive mechanism device provided superior closure compared with the single–occlusive mechanism device at both 45 days and 1 year postprocedure. PDL ≥3 mm was associated with a significantly increased 18-month risk for the composite of stroke, systemic embolism, or cardiovascular death. Completeness of closure of the left atrial appendage has important implications for patient outcomes. (AMPLATZER? Amulet? LAA Occluder Trial [Amulet IDE]; NCT02879448)     

Sex Differences in Safety and Effectiveness of LAAO: Insights From the Amulet IDE Trial

BackgroundWomen have higher rates of acute complications after left atrial appendage occlusion (LAAO). However, data on long-term safety and effectiveness are limited.ObjectivesThe aim of this study was to examine sex-specific short- and long-term outcomes after LAAO in the Amulet IDE (Amplatzer? Amulet? LAA Occluder) trial.MethodsThe following outcomes were compared between men and women: in-hospital complications, device-related outcomes (peridevice leak at 45 days and device-related thrombus at 18 months), and long-term clinical outcomes (death, thromboembolism, and bleeding). Subanalyses for the interaction between sex and device type were performed.ResultsA total of 1,833 patients underwent attempted device implantation (917 with the Amulet and 916 with the Watchman), of whom 734 were women (40%). Device success was 97.4% in men and 97.1% in women (P = 0.60). Rates of major in-hospital adverse events were higher in women (4.4% vs 1.9%; P < 0.01), driven by major bleeding (3.7% vs 1.0%; P < 0.01) and pericardial effusion requiring intervention (2.0% vs 0.5%; P < 0.01). Peridevice leak and device-related thrombus were similar in men and women (18.3% vs 18.9% [P = 0.78] and 3.3% vs 5.0% [P = 0.10], respectively). There were no differences between men and women in rates of ischemic stroke or systemic embolism (2.6% vs 2.6%; P = 0.98), transient ischemic attack (1.3% vs 1.6%; P = 0.69), hemorrhagic stroke (0.5% vs 0.4%; P = 0.88), major bleeding (10.1% vs 10.9%; P = 0.49), cardiovascular death (4.3% vs 3.5%; P = 0.45), or all-cause death (8.9% vs 6.9%; P = 0.16).ConclusionsIn the Amulet IDE trial, long-term clinical outcomes including effectiveness following LAAO were comparable in men and women despite the higher rates of in-hospital complications due to major bleeding and pericardial effusion in women. (Amplatzer? Amulet? LAA Occluder Trial [Amulet IDE]; NCT02879448)     

The Impact of CHA2DS2-VASc and HAS-BLED Scores on Clinical Outcomes in the Amplatzer Amulet Study

ObjectivesThe aim of this study was to evaluate the impact of CHA₂DS₂-VASc and HAS-BLED scores on ischemic and bleeding events of patients enrolled in the Amplatzer Amulet Observational Study.BackgroundBaseline CHA₂DS₂-VASc and HAS-BLED scores have been validated in atrial fibrillation patients to guide about anticoagulation but not in patients treated by left atrial appendage occlusion (LAAO).MethodsSubjects were stratified according to CHA₂DS₂-VASc and HAS-BLED scores. Clinical outcomes were collected through 2 years and adjudicated by an independent committee.ResultsSubjects were considered at low (n = 156), moderate (n = 715), and high (n = 215) risk for ischemic stroke, corresponding to CHA₂DS₂-VASc scores of <3, 3 to 5, and ≥6, respectively. The annual rates of ischemic stroke were 1.1%, 2.0%, and 3.5%, respectively. When compared with the predicted rate, LAAO reduced the risk of ischemic stroke by 56%, 69%, and 68%. Device-related thrombus occurred in 0.7%, 1.5%, and 3.0% of subjects at low, moderate, and high risk for ischemic stroke, respectively. The HAS-BLED score was ≤3 in 629 subjects and >3 in 456 subjects, respectively. Non-peri-procedural major bleeding was reduced by 11% and 9% compared with predicted rates in the low and high bleeding risk groups, respectively.ConclusionsLAAO with the Amplatzer Amulet reduced the risk of ischemic stroke compared with the predicted rate, with a greater magnitude among patients at high thromboembolic risk without increasing the bleeding risk. (Amplatzer™Amulet™ Post-Market Study [Amulet™PMS]; NCT02447081)     

Clinical Outcomes Associated With Left Atrial Appendage Occlusion Versus Direct Oral Anticoagulation in Atrial Fibrillation

ObjectivesThis study sought to investigate clinical outcomes associated with left atrial appendage occlusion (LAAO) versus direct oral anticoagulants (DOACs) in patients with high-risk atrial fibrillation (AF).BackgroundLAAO has been shown to be noninferior to warfarin for stroke prevention in AF. However, anticoagulation with DOACs is now preferred over warfarin as thromboprophylaxis in AF.MethodsPatients with AF enrolled in the Amulet Observational Registry (n = 1,088) who had successful LAAO with the Amplatzer Amulet device (n = 1,078) were compared with a propensity score–matched control cohort of incident AF patients (n = 1,184) treated by DOACs identified from Danish national patient registries. Propensity score matching was based on the covariates of the CHA₂DS₂-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism, vascular disease, age 65–74 years, sex category) and HAS-BLED (hypertension, abnormal renal or liver function, stroke, bleeding, labile international normalized ratio, elderly, drugs or alcohol) scores for predicting stroke and bleeding. The primary outcome was a composite of ischemic stroke, major bleeding (Bleeding Academic Research Consortium ≥3), or all-cause mortality, and follow-up was 2 years.ResultsAF patients treated with LAAO had a significantly lower risk of the primary composite outcome as compared with patients treated with DOACs (hazard ratio [HR]: 0.57; 95% confidence interval [CI]: 0.49 to 0.67). Total events and event rates per 100 patient-years were (LAAO vs. DOACs) 256 vs. 461 and 14.5 vs. 25.7, respectively. The risk of ischemic stroke was comparable between groups (HR: 1.11; 95% CI: 0.71 to 1.75), while risk of major bleeding (HR: 0.62; 95% CI: 0.49 to 0.79) and all-cause mortality (HR: 0.53; 95% CI: 0.43 to 0.64) were significantly lower in patients treated with LAAO.ConclusionsAmong high-risk AF patients, LAAO in comparison with DOACs may have similar stroke prevention efficacy but lower risk of major bleeding and mortality.     

Procedural and Short-Term Results With the New Watchman FLX Left Atrial Appendage Occlusion Device

ObjectivesThis study sought to report early experience with the new-generation Watchman FLX device (Boston Scientific, Marlborough, Massachusetts).BackgroundThe new-generation Watchman FLX features a reduced height, improved anchoring and fabric coverage, and a closed distal end. These design modifications aim to simplify implantation, allow full recapture and repositioning, and reduce peridevice leak and device-related thrombosis.MethodsA total of 165 patients undergoing left atrial appendage (LAA) occlusion (LAAO) with Watchman FLX were enrolled in a prospective, multicenter registry at 12 centers participating in the European limited market release program.ResultsMean age was 75.4 ± 8.9 years, and CHA₂DS₂-VASc score 4.4 ± 1.4. A total of 128 patients (77.6%) had a history of major bleeding, including previous intracranial hemorrhage in 55 cases (33.3%). LAA landing zone minimal and maximal mean diameters were 19.1 ± 3.6 mm and 22.3 ± 3.7 mm, and 24.2% of LAA were considered complex by dimensions. Technical success was achieved in all patients. Successful implantation at first attempt was achieved in 129 cases (78.2%), and a second device was required in 6 cases (3.6%). Procedure-related complications occurred in 3 patients (1.8%): 2 access-related (1.2%) and 1 pericardial effusion (0.6%). No peri-procedural strokes, deaths, or device embolizations occurred. Forty-nine patients (29.7%) were discharged with single antiplatelet therapy, 105 (63.6%) on dual antiplatelet, and 11 (6.7%) on anticoagulation. Imaging follow-up displayed just 1 peridevice leak ≥5 mm and 7 cases of device-related thrombosis (4.7%). During a median follow-up of 55 days (interquartile range: 45 to 148 days), there were 6 hemorrhagic complications (4.8%), 1 patient (0.8%) had an ischemic stroke, and 1 (0.8%) died. No late device embolizations occurred.ConclusionsLAAO with the Watchman FLX is safe and effective in a wide range of LAA morphologies, with a low procedural complication rate, high degree of LAA sealing, and favorable short-term efficacy.     

Patient-Level Analysis of Watchman Left Atrial Appendage Occlusion in Practice Versus Clinical Trials

ObjectivesThe aim of this study was to compare outcomes among patients from the PROTECT-AF (WATCHMAN Left Atrial Appendage System for Embolic PROTECTion in Patients With Atrial Fibrillation) and PREVAIL (Evaluation of the WATCHMAN Left Atrial Appendage [LAA] Closure Device in Patients With Atrial Fibrillation Versus Long Term Warfarin Therapy) left atrial appendage occlusion (LAAO) trials with matched patients from the National Cardiovascular Data Registry LAAO Registry using patient-level data.BackgroundPatients undergoing LAAO in clinical practice generally have more comorbidities than trial participants.MethodsPropensity-matched analyses, with up to 3 registry patients matched to each trial patient, were performed using Cox proportional hazards and Fine-Gray models.ResultsA total of 1,904 registry patients were matched to 667 trial LAAO patients; 1,010 registry patients were matched to 348 warfarin patients. Compared with registry patients, trial LAAO patients experienced more pericardial effusion requiring intervention (3.8% vs 0.6%, P < 0.001), periprocedural ischemic stroke (0.9% vs 0.2%, P = 0.005), and failed device implantation (7.5% vs 3.6%, P < 0.001). The 425-day risk of ischemic stroke in trial LAAO patients was higher than in registry patients (2.70% vs 1.21%; HR: 1.951; P = 0.03); warfarin patients had comparable rates of ischemic stroke compared with registry patients (1.15% vs 1.29%; HR: 0.728; P = 0.57). Hemorrhagic stroke risk was similar among trial LAAO and registry patients (P = 0.88). Hemorrhagic stroke risk was greater among warfarin patients versus registry patients (1.44% vs 0.20%; HR: 5.871, P = 0.03). Mortality was lower in trial LAAO patients than in registry patients (2.92% vs 6.23%; HR: 0.477; P = 0.004), a difference attributable to noncardiovascular deaths. Mortality was similar (P = 0.44) among trial warfarin (4.48%) and registry (5.86%) patients.ConclusionIn clinical practice, patients who meet trial criteria and undergo LAAO experience a lower risk of ischemic stroke, a similar risk of hemorrhagic stroke, and a higher risk of death after implant versus LAAO trial patients. (WATCHMAN Left Atrial Appendage System for Embolic PROTECTion in Patients With Atrial Fibrillation [PROTECT-AF], NCT00129545; Evaluation of the WATCHMAN Left Atrial Appendage [LAA] Closure Device in Patients With Atrial Fibrillation Versus Long Term Warfarin Therapy [PREVAIL], NCT01182441)     

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

ObjectivesThis study aimed to investigate cardiac computed tomography (CT) and transesophageal echocardiography (TEE) peridevice leak (PDL) assessments, and the clinical relevance of PDL.BackgroundPDL assessment is integral during follow-up after left atrial appendage (LAA) occlusion. Comparative studies of TEE and cardiac CT are sparse, and the clinical relevance of PDL is uncertain.MethodsThis was a single-center observational study of consecutive patients undergoing LAA occlusion with Amplatzer devices (Amplatzer Cardiac Plug/Amulet) between 2010 and 2018 (N = 415). Patients with both 8-week CT and TEE were included for analysis (n = 346). Images were analyzed by blinded investigators (K.K. and A.S.). PDL on cardiac CT was classified from grade 1 to 3, based on PDL at the device disc, device lobe, and LAA contrast patency. Primary clinical outcome was a composite of ischemic stroke, transient ischemic attack, systemic embolism, or all-cause death.ResultsPDL was present in 110 patients (32%) by TEE, with 29 (8%) >3 mm. By cardiac CT, 210 patients (61%) had PDL at the disc, with contrast patency in 204 patients (59%). A grade 3 PDL (gap at disc, lobe, and LAA contrast patency) was present in 63 patients (18%). Bland-Altman analysis showed poor agreement between CT and TEE for leak sizing. CT and TEE detected PDL was not significantly associated with worse outcome, hazard ratio: 1.82 (95 % confidence interval: 0.95 to 3.50); p = 0.07 and hazard ratio: 1.43 (95% confidence interval: 0.74 to 2.76); p = 0.28, respectively.ConclusionsPDL occurrence is substantially higher with CT compared with TEE, with a large discrepancy between modalities in leak quantification. A novel CT-based classification is proposed, yet PDL was not associated with worse clinical outcome.     

First Experience of Transcatheter Leak Occlusion With Detachable Coils Following Left Atrial Appendage Closure

ObjectivesThe aim of this study was to assess the feasibility and efficacy of transcatheter leak closure with detachable coils in patients with incomplete left atrial appendage (LAA) closure.BackgroundIncomplete LAA closure is common after interventional therapies targeting the LAA, potentially hindering effective thromboembolic prevention. Detachable coils have found a wide range of applications for transcatheter vascular occlusion and embolization procedures.MethodsThirty consecutive patients at high thromboembolic risk with clinically relevant residual leaks (mean age 72 ± 9 years, 73.3% men, mean CHA₂DS₂-VASc score 4.4 ± 1.4, mean HAS-BLED score 3.6 ± 0.8) underwent percutaneous closure of the LAA patency using embolization coils. Transesophageal echocardiography was performed at 60 ± 15 days post-procedure.ResultsLAA closure had been previously attempted with the Watchman device in 25 patients, the Amulet device in 2 patients, and the LARIAT device in 3 patients. Baseline transesophageal echocardiography documented moderate and severe leaks in 20 (66.7%) and 10 (33.3%) patients, respectively. After a single procedure, 25 patients (83.3%) showed complete LAA sealing or minimal leaks. Five patients (16.7%) had moderate residual leaks; 3 patients of them were offered repeat procedures. Mean procedure and fluoroscopy times were 76 ± 41 min and 21 ± 14 min, respectively; the mean volume of iodinated contrast medium used was 80 ± 47 ml. Coil deployment was successful in all cases. The overall complication rate was 6.1%. After a median follow-up period of 54 days (range 43 to 265 days) and an average of 1.1 procedures/patient, transesophageal echocardiography revealed complete LAA sealing or negligible residual leaks in 28 patients (93.3%; 25 with no residual leak, 3 patients with minimal to mild residual leaks) and moderate residual leaks in 2 patients (6.7%).ConclusionsTranscatheter LAA leak occlusion using endovascular coils appears to be a safe, effective, and promising approach in patients at high echo time risk with incomplete LAA closure. (Transcatheter Leak Closure With Detachable Coils Following Incomplete Left Atrial Appendage Closure Procedures [TREASURE]; NCT03503253)     

Comparative Safety of Transcatheter LAAO With the First-Generation Watchman and Next-Generation Watchman FLX Devices

BackgroundProcedural complications limit the clinical benefit of transcatheter left atrial appendage occlusion (LAAO). Next-generation devices incorporate design modifications intended to improve procedural safety, but their clinical impact has not been described.ObjectivesThe aim of this study was to compare in-hospital outcomes for the Watchman FLX with the predicate Watchman 2.5 device.MethodsThe National Cardiovascular Data Registry LAAO Registry was used to identify patients who received the Watchman FLX and an identical number of patients receiving the Watchman 2.5 at the same sites directly preceding the first Watchman FLX case at each site. The primary endpoint was in-hospital major adverse events (MAE), defined as a composite of death, cardiac arrest, stroke, transient ischemic attack, intracranial hemorrhage, systemic arterial embolism, major bleeding, major vascular complication, myocardial infarction, pericardial effusion requiring intervention (percutaneous or surgical), and device embolization. A secondary analysis was performed using 2:1 propensity score matching of patients receiving the Watchman 2.5 or Watchman FLX.ResultsThe study cohort consisted of 27,013 patients receiving each device. The rate of in-hospital MAE was significantly lower for the Watchman FLX compared with the Watchman 2.5 (1.35% vs 2.40%; adjusted OR: 0.57; 95% CI: 0.50-0.65; P < 0.0001), driven largely by fewer pericardial effusions requiring intervention (0.42% vs 1.23%; adjusted OR: 0.34; 95% CI: 0.28-0.42; P < 0.0001). The Watchman FLX was also associated with significant lower rates of the individual endpoints of in-hospital mortality (0.12% vs 0.24%; P < 0.0001), major bleeding (1.08% vs 2.05%; P < 0.0001), cardiac arrest (0.13% vs 0.24%; P = 0.006), and device embolization (0.02% vs 0.06%; P = 0.028), while myocardial infarction, stroke, and major vascular complications did not differ between groups. Propensity score matching analysis demonstrated similar results, with lower rates of MAE with the Watchman FLX (1.34% vs 2.58%; OR: 0.51; 95% CI: 0.46-0.58; P < 0.0001).ConclusionsTranscatheter LAAO with the Watchman FLX was associated with lower rates of in-hospital MAE compared with the predicate Watchman device, including mortality, pericardial effusion, major bleeding, cardiac arrest, and device embolization. This may favorably influence the balance of risks and benefits of transcatheter LAAO for stroke prevention in patients with atrial fibrillation.     

The NCDR Left Atrial Appendage Occlusion Registry

BackgroundLeft atrial appendage occlusion (LAAO) to prevent stroke in patients with atrial fibrillation has been evaluated in 2 randomized trials; post-approval clinical data are limited.ObjectivesThe purpose of this study was to describe the National Cardiovascular Data Registry (NCDR) LAAO Registry and present patient, hospital, and physician characteristics and in-hospital adverse event rates for Watchman procedures in the United States during its first 3 years.MethodsThe authors describe the LAAO Registry structure and governance, the outcome adjudication processes, and the data quality and collection processes. They characterize the patient population, performing hospitals, and in-hospital adverse event rates.ResultsA total of 38,158 procedures from 495 hospitals performed by 1,318 physicians in the United States were included between January 2016 and December 2018. The mean patient age was 76.1 ± 8.1 years, the mean CHA₂DS₂-VASc (congestive heart failure, hypertension, 65 years of age and older, diabetes mellitus, previous stroke or transient ischemic attack, vascular disease, 65 to 74 years of age, female) score was 4.6 ± 1.5, and the mean HAS-BLED (hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile international normalized ratio, elderly, drugs/alcohol concomitantly) score was 3.0 ± 1.1. The median annual number of LAAO procedures performed for hospitals was 30 (interquartile range: 18 to 44) and for physicians was 12 (interquartile range: 8 to 20). Procedures were canceled or aborted in 7% of cases; among cases in which a device was deployed, 98.1% were implanted with <5-mm leak. Major in-hospital adverse events occurred in 2.16% of patients; the most common complications were pericardial effusion requiring intervention (1.39%) and major bleeding (1.25%), whereas stroke (0.17%) and death (0.19%) were rare.ConclusionsThe LAAO Registry has enrolled >38,000 patients implanted with the device. Patients were generally older with more comorbidities than those enrolled in the pivotal trials; however, major in-hospital adverse event rates were lower than reported in those trials.     

Clinical Outcomes at 1 Year Following Transcatheter Left Atrial Appendage Occlusion in the United States

ObjectivesThe aim of this study was to report 1-year clinical outcomes following commercial transcatheter left atrial appendage occlusion (LAAO) in the United States.BackgroundThe National Cardiovascular Data Registry LAAO Registry was initiated to meet a condition of Medicare coverage and allow the assessment of clinical outcomes. The 1-year rates of thromboembolic events after transcatheter LAAO in such a large cohort of “real-world” patients have not been previously reported.MethodsPatients entered into the National Cardiovascular Data Registry LAAO Registry for a Watchman procedure between January 1, 2016, and December 31, 2018, were included. The primary endpoint was ischemic stroke. Key secondary endpoints included the rate of ischemic stroke or systemic embolism, mortality, and major bleeding. Major bleeding was defined as any bleeding requiring hospitalization, and/or causing a decrease in hemoglobin level > 2g/dL, and/or requiring blood transfusion that was not hemorrhagic stroke. The Kaplan-Meier method was used for 1-year estimates of cumulative event rates.ResultsThe study population consisted of 36,681 patients. The mean age was 76.0 ± 8.1 years, the mean CHA₂DS₂-VASc score was 4.8 ± 1.5, and the mean HAS-BLED score was 3.0 ± 1.1. Prior stroke was present in 25.5%, clinically relevant bleeding in 69.5%, and intracranial bleeding in 11.9%. Median follow-up was 374 days (IQR: 212-425 days). The Kaplan-Meier–estimated 1-year rate of ischemic stroke was 1.53% (95% CI: 1.39%-1.69%), the rate of ischemic stroke or systemic embolism was 2.19% (95% CI: 2.01%-2.38%), and the rate of mortality was 8.52% (95% CI: 8.19%-8.87%). The 1-year estimated rate of major bleeding was 6.93% (95% CI: 6.65%-7.21%). Most bleeding events occurred between discharge and 45 days following the procedure.ConclusionsThis study characterizes important outcomes in a national cohort of patients undergoing transcatheter LAAO in the United States. Clinicians and patients can integrate these data in shared decision making when considering this therapy.     

Half-Dose Direct Oral Anticoagulation Versus Standard Antithrombotic Therapy After Left Atrial Appendage Occlusion

ObjectivesThis study evaluated the long-term efficacy of a standard antithrombotic strategy versus half-dose direct oral anticoagulation (DOAC) after Watchman implantation.BackgroundNo consensus currently exists on the selection of the most effective antithrombotic strategy to prevent device-related thrombosis (DRT) in patients undergoing endocardial left atrial appendage closure.MethodsAfter successful left atrial appendage closure, consecutive patients were prescribed a standard antithrombotic strategy (SAT) or long-term half-dose DOAC (hdDOAC). The primary composite endpoint was DRT and thromboembolic (TE) and bleeding events.ResultsOverall, 555 patients (mean age 75 ± 8 years, 63% male; median CHA₂DS₂-VASc [congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism, vascular disease, age 65-74 years, sex category] score 4 [interquartile range (IQR): 3-6]; median HAS-BLED [hypertension, abnormal renal or liver function, stroke, bleeding, labile international normalized ratio, elderly, drugs or alcohol] score 3 [IQR: 2-4]) were included. Patients were categorized into 2 groups (SAT: n = 357 vs hdDOAC: n = 198). Baseline clinical characteristics were similar between groups. The median follow-up duration was 13 months (IQR: 12-15 months). DRT occurred in 12 (2.1%) patients, all in the SAT group (3.4% vs 0.0%; log-rank P = 0.009). The risk of nonprocedural major bleeding was significantly more favorable in the hdDOAC group (0.5% vs. 3.9%; log-rank P = 0.018). The rate of the primary composite endpoint of DRT and TE and major bleeding events was 9.5% in SAT patients and 1.0% in hdDOAC patients (HR: 9.8; 95% CI: 2.3-40.7; P = 0.002).ConclusionsAfter successful Watchman implantation, long-term half-dose DOAC significantly reduced the risk of the composite endpoint of DRT and TE and major bleeding events compared with a standard, antiplatelet-based, antithrombotic therapy.     

Association of Hospital Procedural Volume With Outcomes of Percutaneous Left Atrial Appendage Occlusion

ObjectivesThe aim of this study was to examine the association between percutaneous left atrial appendage occlusion (LAAO) procedural volume and in-hospital outcomes.BackgroundSeveral studies have demonstrated an inverse volume-outcome relationship for patients undergoing invasive cardiac procedures. Whether a similar association exists for percutaneous LAAO remains unknown.MethodsPatients undergoing LAAO in 2017 were identified in the Nationwide Readmissions Database. Hospitals were categorized into 3 groups on the basis of tertiles of annual procedural volume: low (5 to 15 cases/year), medium (17 to 31 cases/year), and high (32 to 211 cases/year). Multivariate hierarchical logistic regression and restricted cubic spline analyses were performed to examine the association of hospital LAAO volume and outcomes. The primary outcome was in-hospital major adverse events (MAE), defined as a composite of mortality, stroke or transient ischemic attack, bleeding or transfusion, vascular complications, myocardial infarction, systemic embolization, and pericardial effusion or tamponade requiring pericardiocentesis or surgery.ResultsThis study included 5,949 LAAO procedures performed across 196 hospitals with a median annual procedural volume of 41 (interquartile range: 25 to 67). Low-volume hospitals had higher rates of in-hospital MAE (9.5% vs. 5.6%; p < 0.001), stroke or transient ischemic attack (2.1% vs. 1.3%; p = 0.049), and bleeding or transfusion (6.1% vs. 3.5%; p = 0.002) compared with high-volume hospitals. No differences were noted for other components of MAE and index length of stay. On multivariate analysis, higher procedural volume was associated with lower rates of in-hospital MAE, with an adjusted odds ratio for medium versus low volume of 0.69 (95% confidence interval: 0.46 to 1.04; p = 0.08) and for high versus low volume of 0.55 (95% confidence interval: 0.37 to 0.82; p = 0.003).ConclusionsHigher hospital procedural volume is associated with better outcomes for LAAO procedures. Further studies are needed to determine if this relationship persists for long-term outcomes.     

Evaluation of Multimodality LAA Leak Closure Methods Following Incomplete Occlusion: The LAA Leak Study

BackgroundIncomplete left atrial appendage (LAA) closure is an evolving topic of clinical significance and thromboembolic potential, with recent long-term studies suggesting lower cutoffs for relevant leak size.ObjectivesThe aim of this prospective observational study was to assess 3 different closure techniques for persistent peridevice leaks after incomplete LAA closure and compare their efficacy and safety outcomes.MethodsWe studied 160 patients (mean age 72 ± 9 years; 71% men) who underwent 1 of the 3 available modalities (detachable embolization coils, vascular plugs or septal occluders, and radiofrequency ablation) for residual central or eccentric leak closure. Both acute postprocedural success (closure or <1-mm leak at the end of the procedure) and closure at 1-year follow-up transesophageal echocardiography imaging were evaluated.ResultsOf 160 patients, 0.6%, 41.3%, and 58.1% had mild (1-2 mm), moderate (3-5 mm), and severe (≥5 mm) leaks, respectively. Baseline LAA closure type was 72.5% Watchman FLX, 16.3% Lariat, 5.6% surgical ligation, 1.9% AtriClip, and 1.9% Amulet. Successful closure (0- or <1-mm leak) was seen in 100% of patients in all cohorts following intervention, with overall complete closure (0-1 mm) or mild or minimal leaks (1-2 mm) on 1-year follow-up transesophageal echocardiography seen in 100% of the atrial septal occluder or vascular plug cohort, 85.9% of the coil cohort, and 83.3% of the radiofrequency ablation cohort (P < 0.001). Two patients (1.3%) experienced cardiac tamponade, and there were no deaths or other complications.ConclusionsPeridevice leaks can safely and effectively be closed using 3 different modalities depending on size and location.     

Detection and Characterization of Thrombosis in Humans Using Fibrin-Targeted Positron Emission Tomography and Magnetic Resonance

ObjectivesThe authors present a novel technique to detect and characterize LAA thrombus in humans using combined positron emission tomography (PET)/cardiac magnetic resonance (CMR) of a fibrin-binding radiotracer, [⁶⁴Cu]FBP8.BackgroundThe detection of thrombus in the left atrial appendage (LAA) is vital in the prevention of stroke and is currently performed using transesophageal echocardiography (TEE).MethodsThe metabolism and pharmacokinetics of [⁶⁴Cu]FBP8 were studied in 8 healthy volunteers. Patients with atrial fibrillation and recent TEEs of the LAA (positive n = 12, negative n = 12) were injected with [⁶⁴Cu]FBP8 and imaged with PET/CMR, including mapping the longitudinal magnetic relaxation time (T₁) in the LAA.Results[⁶⁴Cu]FBP8 was stable to metabolism and was rapidly eliminated. The maximum standardized uptake value (SUV_Max) in the LAA was significantly higher in the TEE-positive than TEE-negative subjects (median of 4.0 [interquartile range (IQR): 3.0-6.0] vs 2.3 [IQR: 2.1-2.5]; P < 0.001), with an area under the receiver-operating characteristic curve of 0.97. An SUV_Max threshold of 2.6 provided a sensitivity of 100% and specificity of 84%. The minimum T₁ (T_1Min) in the LAA was 970 ms (IQR: 780-1,080 ms) vs 1,380 ms (IQR: 1,120-1,620 ms) (TEE positive vs TEE negative; P < 0.05), with some overlap between the groups. Logistic regression using SUV_Max and T_1Min allowed all TEE-positive and TEE-negative subjects to be classified with 100% accuracy.ConclusionsPET/CMR of [⁶⁴Cu]FBP8 is able to detect acute as well as older platelet-poor thrombi with excellent accuracy. Furthermore, the integrated PET/CMR approach provides useful information on the biological properties of thrombus such as fibrin and methemoglobin content. (Imaging of LAA Thrombosis; NCT03830320)     

Conformal Left Atrial Appendage Seal Device for Left Atrial Appendage Closure: First Clinical Use

ObjectivesThe authors report the first clinical experience with the Conformal Left Atrial Appendage Seal (CLAAS) device.BackgroundThe CLAAS device was designed to address the limitations of first-generation left atrial appendage closure (LAAC) devices by providing an implant that is minimally traumatic, can be deployed in a noncoaxial fashion, and does not require postprocedural oral anticoagulation.MethodsPatients with atrial fibrillation at high stroke risk (CHA₂DS₂-VASc score ≥2) were recruited using standard selection criteria. The LAAC procedure was guided by transesophageal echocardiography with patients under general anesthesia. The CLAAS device is composed of a foam cup, with a Nitinol endoskeleton with an expanded polytetrafluoroethylene cover, delivered with a standard delivery system using a tether for full recapture. All patients received dual-antiplatelet therapy for 6 months, followed by aspirin alone. Transesophageal echocardiographic follow-up was scheduled for 45 days and 1 year.ResultsTwenty-two patients (63.7% with CHA₂DS₂-VASc scores ≥3, 76.2% with HAS-BLED scores ≥3) were enrolled. The device was successfully implanted in 18 patients and unsuccessfully in 4 patients. There were no serious procedural complications. On transesophageal echocardiography performed at 45 days, 1 significant leak (≥5 mm) was seen, which was due to a large posterior lobe not appreciated at the time of implantation, and 1 device-related thrombus was noted, which resolved on oral anticoagulation. There were no periprocedural strokes, major pericardial effusions, or systemic or device embolization.ConclusionsThis first-in-human study demonstrates the clinical feasibility of the CLAAS device for LAAC.     

Cierre de la orejuela izquierda por ictus pese a la anticoagulación oral (ictus resistente): resultados del registro Amplatzer Cardiac Plug

Introduction and objectivesDespite the efficacy of oral anticoagulant (OAC) therapy, some patients continue to have a high residual risk and develop a stroke on OAC therapy (resistant stroke [RS]), and there is a lack of evidence on the management of these patients. The aim of this study was to analyze the safety and efficacy of left atrial appendage occlusion (LAAO) as secondary prevention in patients with nonvalvular atrial fibrillation who have experienced a stroke/transient ischemic attack despite OAC treatment.MethodsWe analyzed data from the Amplatzer Cardiac Plug multicenter registry on 1047 consecutive patients with nonvalvular atrial fibrillation undergoing LAAO. Patientes with previous stroke on OAC therapy as indication for LAAO were identified and compared with patients with other indications.ResultsA total of 115 patients (11%) with RS were identified. The CHA₂DS₂-VASc and the HAS-BLED score were significantly higher in the RS group (respectively 5.5 ± 1.5 vs 4.3 ± 1.6; P < .001; 3.9 ± 1.3 vs 3.1 ± 1.2; P < .001). No significant differences were observed in periprocedural major safety events (7.8 vs 4.5%; P = .1). With a mean clinical follow-up of 16.2 ± 12.2 months, the observed annual stroke/transient ischemic attack rate for the RS group was 2.6% (65% risk reduction) and the observed annual major bleeding rate was 0% (100% risk reduction).ConclusionsPatients with RS undergoing LAAO showed similar safety outcomes to patients without RS, with a significant reduction in stroke/transient ischemic attack and major bleeding events during follow-up. Adequately powered controlled trials are needed to further investigate the use of LAAO in RS patients.     

Clinical Characteristics and Prognostic Importance of Left Ventricular Apical Aneurysms in Hypertrophic Cardiomyopathy

BackgroundLeft ventricular (LV) apical aneurysms in hypertrophic cardiomyopathy (HCM) are a recognized risk marker for adverse cardiovascular events. There is variable practice among clinicians and discordance between international guidelines regarding treatment recommendations and prognostication for this important phenotype.ObjectivesThe authors sought to describe the morphology, clinical course, and risk of adverse events in a large single-center cohort of HCM patients with LV apical aneurysms.MethodsThis study analyzed 160 HCM patients with an LV apical aneurysm who were evaluated in our dedicated HCM clinic between January 1997 and April 2021.ResultsMean age was 59.1 ± 13.6 years, and 71% of these patients were male. Mean aneurysm size was 1.77 ± 1.04 cm. Over 6.2 ± 4.8 years, 14 (9%) patients had a sudden cardiac death (SCD) event, including appropriate therapy from an implantable cardioverter-defibrillator (ICD) or resuscitation from cardiac arrest (annualized event rate 1.77%/y), 39 (24%) had either a thromboembolic stroke or apical thrombus formation (2.9%/y), and 14 (9%) developed LV systolic dysfunction with an ejection fraction (EF) <50% (1.28%/y). HRs for SCD, stroke or thrombus, and EF <50% per 1-cm increase in aneurysm size were 1.69 (P = 0.007), 1.60 (P = 0.0002), and 1.63 (P = 0.01), respectively. Aneurysm size ≥2 cm was associated with a 5-year SCD rate of 9.7%, compared with 2.9% for aneurysm size <2 cm (log-rank P = 0.037). This subgroup also had higher risk of stroke/thrombus formation (HR: 2.20; P = 0.002), with an annualized event rate of 2.7%/year. A total of 39 (24%) patients reached the combined end point of SCD, stroke, or LV dysfunction (2.12%/y) with an HR of 1.47/cm increase in aneurysm size (P = 0.003) and an HR of 2.22 for patients with aneurysm size ≥2 cm (P = 0.02).ConclusionsIncreasing aneurysm size confers poorer prognosis. Aneurysm size ≥2 cm should alert potential consideration for prophylactic anticoagulation and primary prevention ICDs.     

Mechanical Thrombectomy for Acute Ischemic Stroke in the Cardiac Catheterization Laboratory

ObjectivesThe aim of this study was to determine the feasibility of establishing a mechanical thrombectomy (MT) program for acute ischemic stroke in a community hospital using interventional cardiologists working closely with neurologists.BackgroundAmerican Heart Association/American Stroke Association 2018 guidelines give a Class I (Level of Evidence: A) recommendation for MT in eligible patients with large vessel occlusion stroke. Improvement in neurological outcomes with MT is highly time sensitive. Most hospitals do not have trained neurointerventionalists to perform MT, leading to treatment delays that reduce the benefit of reperfusion therapy.MethodsAn MT program based in the cardiac catheterization laboratory was developed using interventional cardiologists with ST-segment elevation myocardial infarction teams.ResultsForty patients underwent attempted MT for acute ischemic stroke. An additional 5 patients who underwent angiography did not undergo attempted thrombectomy, because of absence of target thrombus (n = 4) or unsuitable anatomy (n = 1). Median National Institutes of Health Stroke Scale score prior to MT was 19 and at discharge was 7. TICI (Thrombolysis In Cerebral Infarction) grade 2b or 3 flow was restored in 80% of patients (32 of 40). At 90 days, 55% of patients (22 of 40) were functionally independent (modified Rankin score ≤2). In-hospital mortality was 13% (5 of 40). Symptomatic intracranial hemorrhage occurred in 15% of patients (6 of 40). Major vascular complications occurred in 5% of patients (2 of 40).ConclusionsMT can be successfully performed by interventional cardiologists with carotid stenting experience working closely with neurologists in hospitals lacking formally trained neurointerventionists. This model has the potential to increase access to timely care for patients with acute ischemic stroke.     

Watchman Occlusion in Long-Standing Persistent Atrial Fibrillation: Larger Left Atrial Appendages With Greater Residual Leak

ObjectivesThis study sought to compare patients with and without long-standing persistent atrial fibrillation (LSPAF) undergoing Watchman left atrial appendage (LAA) occlusion.BackgroundAn increased burden of atrial fibrillation is associated with progressive left atrial remodeling and enlargement.MethodsTransesophageal echocardiography (TEE) measures of LAA ostial diameter and depth, device compression, and residual leak were evaluated in 101 consecutive Watchman cases. The patients were categorized into LSPAF (n = 48) or non-LSPAF (n = 53) groups and compared.ResultsThe average LAA ostial diameter for LSPAF versus non-LSPAF by TEE omniplane at 0° was 21.1 ± 4.1 mm versus 18.2 ± 3.6 mm (p = 0.0002); at 45° was 18.7 ± 3.4 mm versus 16.3 ± 3.1 mm (p = 0.0004); at 90° was 19.6 ± 3.8 mm versus 16.2 ± 3.4 mm (p = 0.00001); and at 135° was 21.0 ± 4.1 mm versus 18.0 ± 4.1 mm (p = 0.0005). The average LAA depth for LSPAF versus non-LSPAF by TEE at 0° was 28.1 ± 6.4 mm versus 25.2 ± 4.9 mm (p = 0.02); at 45° was 27.9 ± 5.8 mm versus 25.1 ± 4.3 mm (p = 0.007); at 90° was 27.2 ± 5.2 mm versus 22.8 ± 3.7 mm (p = 0.0001); and at 135° was 25.6 ± 5.4 mm versus 21.5 ± 3.8 mm (p = 0.0001). In successfully treated patients, 77% of the LSPAF group received larger device (27, 30, or 33 mm) implants versus only 46% in the non-LSPAF group (p = 0.003). While both groups had similar rates of moderate (3 to 5 mm) leaks at implant (2% vs. 0%; p = 0.14), 27% of the LSPAF vs. 4% of the non-LSPAF group had moderate leaks (p = 0.04) on 6-week follow-up TEE.ConclusionsPatients with LSPAF have significantly larger LAA sizes, require larger devices, and have more residual leak on follow-up TEE. LSPAF may represent a higher risk group that warrants more stringent long-term follow-up.