Left Atrial Appendage Closure Technology Research Articles

Impact of Operator Experience on Left Atrial Appendage Occlusion Outcomes.

The relationship between long-term outcomes and operator experience for left atrial appendage occlusion (LAAO) is still unknown. This study sought to explore the association between operator LAAO experience and one-year clinical outcomes. The RECORD study (Registry to Evaluate Chinese Real-World Clinical Outcomes in Patients With AF Using the WATCHMAN Left Atrial Appendage Closure Technology; NCT03917563) was a multicenter, prospective registry that included patients with the WATCHMAN LAAO device (Boston Scientific) in China from April 1, 2019, to October 31, 2020. The current analyses included patients with solely LAAO from the registry; those who had concomitant LAAO and ablation/other procedures were excluded. The primary outcome was a composite endpoint of death, stroke, systemic embolism, and Bleeding Academic Research Consortium (BARC)-defined type 3 or 5 bleeding at 1 year. A total of 1,547 LAAO patients and 111 operators were included. The mean ± SD CHA2DS2-VASc and HAS-BLED scores of patients were 4.0 ± 1.8 and 2.5 ± 1.1, respectively. The mean ± SD age of operators was 47.0 ± 7.2 years, 15(13.5%) were female, and 52 (46.8%) were electrophysiologists. Utilizing maximally selected log-rank statistics, the thresholds to categorize an experienced operator were performing≥32 LAAOs annually or≥134 LAAOs in total. Performing≥32 LAAOs annually is the better criterion than≥134 LAAOs in total (absolute net reclassification index: 25.79%; P< 0.001). Compared with the≥32 LAAO annually group, the<32 group was associated with a 1.8-fold (HRadjusted: 1.79; 95%CI: 1.16-2.78; P=0.009) increase in the risk of the primary endpoint, and such risk in the<32 group can be reduced by ∼12% after performing each additional 5 cases (HRadjusted per 5 cases: 0.88; 95%CI: 0.78-0.99; P=0.033). Performing≥32 LAAOs annually could be a threshold to categorize an experienced operator. Before reaching this threshold, the risk of death, stroke, systemic embolism, and BARC-defined type 3 or 5 bleeding decreased by 12% after every 5 cases performed.

Left Atrial Appendage Occlusion in Patients With Anticoagulation Failure vs Anticoagulation Contraindication

BackgroundLeft atrial appendage occlusion (LAAO) provides mechanical cardioembolic protection for atrial fibrillation (AF) patients who cannot use oral anticoagulation therapy (OAT). Patients with a thrombotic event despite OAT are at high risk for recurrence and may also benefit from LAAO. ObjectivesThis study sought to investigate the efficacy of LAAO in AF patients with a thrombotic event on OAT compared to: 1) LAAO in AF patients with a contraindication for OAT; and 2) historical data. MethodsThe international LAAO after stroke despite oral anticoagulation (STR-OAC LAAO) collaboration included patients who underwent LAAO because of thrombotic events on OAT. This cohort underwent propensity score matching and was compared to the EWOLUTION (Evaluating Real-Life Clinical Outcomes in Atrial Fibrillation Patients Receiving the WATCHMAN Left Atrial Appendage Closure Technology) registry, which represents patients who underwent LAAO because of OAT contraindications. The primary outcome was ischemic stroke. Event rates were compared between cohorts and with historical data without OAT, yielding relative risk reductions based on risk scores. ResultsAnalysis of 438 matched pairs revealed no significant difference in the ischemic stroke rate between the STR-OAC LAAO and EWOLUTION cohorts (2.5% vs 1.9%; HR: 1.37; 95% CI: 0.72-2.61). STR-OAC LAAO patients exhibited a higher thromboembolic risk (HR: 1.71; 95% CI: 1.04-2.83) but lower bleeding risk (HR: 0.39; 95% CI: 0.18-0.88) compared to EWOLUTION patients. The mortality rate was slightly higher in EWOLUTION (4.3% vs 6.9%; log-rank P = 0.028). Relative risk reductions for ischemic stroke were 70% and 78% in STR-OAC LAAO and EWOLUTION, respectively, compared to historical data without OAT. ConclusionsLAAO in patients with a thrombotic event on OAT demonstrated comparable stroke rates to the OAT contraindicated population in EWOLUTION. The thromboembolic event rate was higher and the bleeding rate lower, reflecting the intrinsically different risk profile of both populations. Until randomized trials are available, LAAO may be considered in patients with an ischemic event on OAT.

Left atrial appendage occlusion should be offered only to select atrial fibrillation patients.

Left atrial appendage occlusion should be offered only to select atrial fibrillation patients.

Propensity-Matched Comparison of Oral Anticoagulation Versus Antiplatelet Therapy After Left Atrial Appendage Closure With WATCHMAN

ObjectivesIn this propensity-matched analysis of post–left atrial appendage closure antithrombotic therapy, the safety and effectiveness of oral anticoagulation (OAC) and antiplatelet therapy (APT) were compared. BackgroundLeft atrial appendage closure with the WATCHMAN device is an alternative to OAC in patients with nonvalvular atrial fibrillation, who are at high bleeding risk. Initial trials included 45 days of post-implantation OAC, but registry data suggest that APT may suffice. MethodsPatients from the PROTECT-AF (Watchman Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation), PREVAIL (Watchman LAA Closure Device in Patients With Atrial Fibrillation Versus Long Term Warfarin Therapy), CAP (Continued Access to PROTECT-AF), CAP2 (Continued Access to PREVAIL), ASAP (ASA Plavix Feasibility Study With Watchman Left Atrial Appendage Closure Technology), and EWOLUTION (Registry on WATCHMAN Outcomes in Real-Life Utilization) trials receiving either OAC or APT post-implantation were matched and compared for nonprocedural bleeding and stroke or systemic thromboembolism over 6 months following implantation. Each patient on APT was matched with 2 patients on OAC, with propensity scores derived from age, sex, congestive heart failure, hypertension, diabetes, prior transient ischemic attack or stroke, peripheral vascular disease, left ventricular ejection fraction, renal impairment, and different atrial fibrillation subtypes. ResultsThe cohort on OAC (n = 1,018; 95% receiving warfarin and 5% receiving nonwarfarin OAC) was prescribed 45-day OAC post-implantation (92% also received single APT), followed by 6-month single or dual APT. The cohort on APT (n = 509; 91% receiving dual APT and 9% receiving single APT) received APT for variable durations. Six-month freedom from nonprocedural major bleeding was similar (OAC, 95.7%; APT, 95.5%; p = 0.775) despite more early bleeds with OAC. Freedom from thromboembolism beyond 7 days was similar between groups (OAC, 98.8%; APT, 99.4%; p = 0.089). However, device-related thrombosis was more frequent with APT (OAC, 1.4%; APT, 3.1%; p = 0.018). ConclusionsAfter left atrial appendage closure with the WATCHMAN, although device-related thrombosis was more common with APT, both APT and OAC strategies resulted in similar safety and efficacy endpoints.

Registry to Evaluate Chinese Real-World Clinical Outcomes in Patients With AF Using the WATCHMAN Left Atrial Appendage Closure Technology

Registry to Evaluate Chinese Real-World Clinical Outcomes in Patients With AF Using the WATCHMAN Left Atrial Appendage Closure Technology

Evaluating Real-World Clinical Outcomes in Atrial Fibrillation Patients Receiving the WATCHMAN Left Atrial Appendage Closure Technology: Final 2-Year Outcome Data of the EWOLUTION Trial Focusing on History of Stroke and Hemorrhage.

Left atrial appendage occlusion with WATCHMAN has emerged as viable alternative to vitamin K antagonists in randomized controlled trials. Evaluating real-life clinical outcomes in atrial fibrillation patients receiving the WATCHMAN left atrial appendage closure technology was designed to collect prospective multicenter outcomes of thromboembolic events, bleeding, and mortality for patients implanted with a WATCHMAN in routine daily practice. One thousand twenty patients with a WATCHMAN implant procedure were prospectively followed in 47 centers. Left atrial appendage occlusion indication was based on the European Society of Cardiology guidelines. Follow-up and imaging were performed per local practice up to a median follow-up of 2 years. Included population was old (age 73.4±8.9 years), at high risk for stroke (311 prior ischemic stroke/transient ischemic attack and 153 prior hemorrhagic stroke) and bleeding (318 prior major bleeding), with CHA2DS2-VASc score ≥5 in 49%, hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, Labile international normalized ratio, elderly, drugs/alcohol concomitantly ≥3 in 40% and oral anticoagulation contraindication in 72%. During follow-up, 161 patients (16.4%) died, 22 strokes were observed (1.3/100 patient-years, 83% reduction versus historic data), and 47 major nonprocedural bleeding events (2.7/100 patient-years, 46% reduction versus historic data). Stroke and bleeding rates were consistently lower than historic data in those with prior ischemic (-76% and -41%) or hemorrhagic (-81% and 67%) stroke and prior bleeding (-85% and -30%). Lowest bleeding rates were seen in patients with early discontinuation of dual antiplatelet therapy. Patients with early discontinuation of antithrombotic therapy showed lower bleeding rates, while they were highest for those with prior bleeding. Device thrombus was observed in 34 patients (4.1%) and was not correlated to drug regimen during follow-up ( P=0.28). During the complete 2-year follow-up of Evaluating Real-Life Clinical Outcomes in Atrial Fibrillation Patients Receiving the WATCHMAN Left Atrial Appendage Closure Technology, patients with a WATCHMAN left atrial appendage occlusion device had consistently low rates of stroke and nonprocedural bleeding, although most were contraindicated to oral anticoagulation and used only single antiplatelet therapy or nothing. URL: https://clinicaltrials.gov . Unique identifier: NCT01972282.

Characterization of Cerebrovascular Events After Left Atrial Appendage Occlusion

Cardioembolic strokes are generally more lethal and disabling than other source of strokes. Data from PROTECT AF (Watchman Left Atrial Appendage Closure Technology for Embolic Protection in Patients With Atrial Fibrillation) suggest that strokes after left atrial appendage occlusion (LAAO) with the Watchman device are less disabling than those in the warfarin group. No data assessing the severity of strokes after LAAO with the AMPLATZER Cardiac Plug (ACP) are available. The objective of the study was to evaluate the severity of cerebrovascular events after LAAO with the ACP in a population mostly characterized by an absolute or relative contraindication to oral anticoagulation. Data from the ACP multicenter registry were analyzed. Disabling strokes were defined as those with a modified Rankin score of 3 to 6 at 90days after the event. A total of 1,047 subjects were included. The mean age and CHADS2 score were 75 ± 8years and 2.8 ± 1.3, respectively. Procedural success was achieved in 97.3% and 4.9% of the patients presented procedural major adverse events. Clinical follow-up was complete in 98.2% of patients with a median of 13months. There were 9 strokes (0.9%), 9 transient ischemic attacks (0.9%), and no intracranial hemorrhages (0%) at follow-up. After excluding 2 patients with pre-LAAO disability, functional assessment showed disabling events in 3 (19%) of the remaining 16 patients. The median time of presentation was 420days (interquartile range 234 to 671) after LAAO, and 17 patients (94%) were on single-antiplatelet therapy when the event occurred. According to our results, cerebrovascular events after LAAO with the ACP system were infrequent and mostly nondisabling.

EWOLUTION: Design of a registry to evaluate real-world clinical outcomes in patients with AF and high stroke risk-treated with the WATCHMAN left atrial appendage closure technology.

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and the rate of ischemic stroke attributed to non-valvular AF is estimated at 5% per year. Several multi-center studies established left atrial appendage closure as a safe and effective alternative to oral anticoagulation, but there is a need for additional real world data. The purpose of this observational, prospective, single-arm, multicenter clinical study is to compile real-world clinical outcome data for WATCHMAN™ LAA (left atrial appendage) Closure Technology. One thousand subjects at up to 70 institutions in Europe, the Middle East, and Russia will be enrolled. Patients will be followed for 2 years after WATCHMAN implantation, according to standard medical practice. Primary endpoints include procedural and long-term data including stroke/embolism, bleeding, and death. This article presents the background of the LAAC device and describes the design of the study. Results for peri-procedural analyses are expected toward the end of 2015; long-term follow-up data are expected in the latter half of 2017. The EWOLUTION study will formally expand knowledge of LAA closure into a broader real world setting. © 2015 Wiley Periodicals, Inc.

Percutaneous left atrial appendageclosure: procedural techniques and outcomes.

Percutaneous left atrial appendage closure technology for stroke prevention in patients with atrial fibrillation has significantly advanced in the past 2 decades. Several devices are under clinical investigation, and a few have already received Conformité Européene (CE)-mark approval and are available in many countries. The WATCHMAN device (Boston Scientific, Natick, Massachusetts) has themost supportive data and is under evaluation by the U.S. Food and Drug Administration for warfarin-eligible patients. The Amplatzer Cardiac Plug (St. Jude Medical, Plymouth, Minnesota) has a large real-world experience over the past 5 years, and a randomized trial comparing Amplatzer Cardiac Plug with the WATCHMAN device is anticipated in the near future. The Lariat procedure (SentreHEART Inc., Redwood City, California) has also gained interest lately, but early studies were concerning for high rates of serious pericardial effusion and major bleeding. The current real-world experience predominantly involves patients who are not long-term anticoagulation candidates or who are perceived to have high bleeding risks. This pattern of practice is expected to change when the U.S. Food and Drug Administration approves the WATCHMAN device for warfarin-eligible patients. This paper reviews in depth the procedural techniques, safety, and outcomes of the current leading devices.

Prospective Randomized Evaluation of the Watchman Left Atrial Appendage Closure Device in Patients With Atrial Fibrillation Versus Long-Term Warfarin Therapy: The PREVAIL Trial

BackgroundIn the PROTECT AF (Watchman Left Atrial Appendage Closure Technology for Embolic Protection in Patients With Atrial Fibrillation) trial that evaluated patients with nonvalvular atrial fibrillation (NVAF), left atrial appendage (LAA) occlusion was noninferior to warfarin for stroke prevention, but a periprocedural safety hazard was identified. ObjectivesThe goal of this study was to assess the safety and efficacy of LAA occlusion for stroke prevention in patients with NVAF compared with long-term warfarin therapy. MethodsThis randomized trial further assessed the efficacy and safety of the Watchman device. Patients with NVAF who had a CHADS2 (congestive heart failure, hypertension, age >75 years, diabetes mellitus, and previous stroke/transient ischemic attack) score ≥2 or 1 and another risk factor were eligible. Patients were randomly assigned (in a 2:1 ratio) to undergo LAA occlusion and subsequent discontinuation of warfarin (intervention group, n = 269) or receive chronic warfarin therapy (control group, n = 138). Two efficacy and 1 safety coprimary endpoints were assessed. ResultsAt 18 months, the rate of the first coprimary efficacy endpoint (composite of stroke, systemic embolism [SE], and cardiovascular/unexplained death) was 0.064 in the device group versus 0.063 in the control group (rate ratio 1.07 [95% credible interval (CrI): 0.57 to 1.89]) and did not achieve the prespecified criteria noninferiority (upper boundary of 95% CrI ≥1.75). The rate for the second coprimary efficacy endpoint (stroke or SE >7 days’ postrandomization) was 0.0253 versus 0.0200 (risk difference 0.0053 [95% CrI: –0.0190 to 0.0273]), achieving noninferiority. Early safety events occurred in 2.2% of the Watchman arm, significantly lower than in PROTECT AF, satisfying the pre-specified safety performance goal. Using a broader, more inclusive definition of adverse effects, these still were lower in PREVAIL (Watchman LAA Closure Device in Patients With Atrial Fibrillation Versus Long Term Warfarin Therapy) trial than in PROTECT AF (4.2% vs. 8.7%; p = 0.004). Pericardial effusions requiring surgical repair decreased from 1.6% to 0.4% (p = 0.027), and those requiring pericardiocentesis decreased from 2.9% to 1.5% (p = 0.36), although the number of events was small. ConclusionsIn this trial, LAA occlusion was noninferior to warfarin for ischemic stroke prevention or SE >7 days’ post-procedure. Although noninferiority was not achieved for overall efficacy, event rates were low and numerically comparable in both arms. Procedural safety has significantly improved. This trial provides additional data that LAA occlusion is a reasonable alternative to warfarin therapy for stroke prevention in patients with NVAF who do not have an absolute contraindication to short-term warfarin therapy.

Left Atrial Appendage Closure With the Watchman Device in Patients With a Contraindication for Oral Anticoagulation: The ASAP Study (ASA Plavix Feasibility Study With Watchman Left Atrial Appendage Closure Technology)

The purpose of this study was to assess the safety and efficacy of left atrial appendage (LAA) closure in nonvalvular atrial fibrillation (AF) patients ineligible for warfarin therapy.The PROTECT AF (Watchman Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation) trial demonstrated that LAA closure with the Watchman device (Boston Scientific, Natick, Massachusetts) was noninferior to warfarin therapy. However, the PROTECT AF trial only included patients who were candidates for warfarin, and even patients randomly assigned to the LAA closure arm received concomitant warfarin for 6 weeks after Watchman implantation.A multicenter, prospective, nonrandomized study was conducted of LAA closure with the Watchman device in 150 patients with nonvalvular AF and CHADS₂ (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, and prior stroke or transient ischemic attack) score ≥1, who were considered ineligible for warfarin. The primary efficacy endpoint was the combined events of ischemic stroke, hemorrhagic stroke, systemic embolism, and cardiovascular/unexplained death.The mean CHADS₂ score and CHA₂DS₂-VASc (CHADS₂ score plus 2 points for age ≥75 years and 1 point for vascular disease, age 65 to 74 years, or female sex) score were 2.8 ± 1.2 and 4.4 ± 1.7, respectively. History of hemorrhagic/bleeding tendencies (93%) was the most common reason for warfarin ineligibility. Mean duration of follow-up was 14.4 ± 8.6 months. Serious procedure- or device-related safety events occurred in 8.7% of patients (13 of 150 patients). All-cause stroke or systemic embolism occurred in 4 patients (2.3% per year): ischemic stroke in 3 patients (1.7% per year) and hemorrhagic stroke in 1 patient (0.6% per year). This ischemic stroke rate was less than that expected (7.3% per year) based on the CHADS₂ scores of the patient cohort.LAA closure with the Watchman device can be safely performed without a warfarin transition, and is a reasonable alternative to consider for patients at high risk for stroke but with contraindications to systemic oral anticoagulation. (ASA Plavix Feasibility Study With Watchman Left Atrial Appendage Closure Technology [ASAP]; NCT00851578).