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Updated: Jul 19, 2025
Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation
Published on: February 26, 2013
Mechanisms, predictors, and evolution of severe peri-device leaks with two different left atrial appendage occluders
Dhanunjaya Lakkireddy1, Jens Erik Nielsen-Kudsk2, Stephan Windecker3
1Kansas City Heart Rhythm Institute and Research Foundation, 5100 W 100th St, Suite-200, Overland Park, KS 66211, USA.
Insights
The Amulet LAA occluder showed fewer severe peri-device leaks than the Watchman device in a large trial. This dual-occlusive device offers improved left atrial appendage closure.
Area of Science:
- Cardiology
- Medical Devices
- Interventional Procedures
Background:
- Peri-device leak (PDL) is a key limitation in left atrial appendage occlusion (LAAO).
- The Amulet IDE trial is the largest head-to-head comparison of Amulet and Watchman 2.5 LAAO devices.
Purpose of the Study:
- To assess predictors and mechanistic factors of PDLs in the Amulet IDE trial.
- To compare PDL rates between Amulet and Watchman 2.5 devices.
Main Methods:
- Analysis of images by an independent core lab for severe PDLs (>5 mm).
- Assessment of PDL incidence, mechanistic factors, predictors (propensity score-matched), and evolution over 18 months.
- Randomized comparison of 1878 patients.
Main Results:
- Amulet had significantly fewer severe PDLs than Watchman at 45 days (1.1% vs. 3.2%) and 12 months (0.1% vs. 1.1%).
- Off-axis deployment and missed lobes were key PDL factors for both devices.
- Larger LAA dimensions predicted PDLs with Watchman, but not Amulet. Watchman PDLs largely did not resolve by 18 months.
Conclusions:
- The dual-occlusive Amulet LAA occluder provides superior LAA closure compared to the Watchman 2.5 device.
- Predictors and temporal patterns of severe PDLs were identified in the Amulet IDE trial.
Aims:
Incomplete left atrial appendage occlusion (LAAO) due to peri-device leak (PDL) is a limitation of the therapy. The Amulet IDE trial is the largest randomized head-to-head trial comparing the Amulet and Watchman 2.5 LAAO devices with fundamentally different designs. The predictors and mechanistic factors impacting differences in PDLs within the Amulet IDE trial are assessed in the current analysis.
Methods And Results:
An independent core lab analysed all images for the presence or absence of severe PDL (>5 mm). The incidence, mechanistic factors, predictors using propensity score-matched controls, and evolution of severe PDLs through 18 months were assessed. Of the 1878 patients randomized in the trial, the Amulet occluder had significantly fewer severe PDLs than the Watchman device at 45 days (1.1 vs. 3.2%, P < 0.001) and 12 months (0.1 vs. 1.1%, P < 0.001). Off-axis deployment or missed lobes were leading mechanistic PDL factors in each device group. Larger left atrial appendage (LAA) dimensions including orifice diameter, landing zone diameter, and depth predicted severe PDL with the Watchman device, with no significant anatomical limitations noted with the Amulet occluder. Procedural and device implant predictors were found with the Amulet occluder attributed to the learning curve with the device. A majority of Watchman device severe PDLs did not resolve over time through 18 months.
Conclusion:
The dual-occlusive Amplatzer Amulet LAA occluder provided improved LAA closure compared with the Watchman 2.5 device. Predictors and temporal observations of severe PDLs were identified in the Amulet IDE trial.
Clinical Trial Registration:
https://clinicaltrials.gov Unique identifier NCT02879448.
