Abstract
Abstract The implantation of an occluder in the left atrial appendage (LAA) is an emerging therapy for the treatment of patients suffering from atrial fibrillation and with a contraindication to oral anticoagulation. The LAA occluder (LAAO) provides a reduction of the potential risk of strokes by thromboembolism. Currently, only a few CE-approved devices are available on the market and the number of clinical trials is comparatively low. Furthermore, there is currently no standardized test method available for testing functionality of the occluder, especially for testing safe anchorage and permeability. Therefore, the aim of this study is to establish an in vitro test method to prove anchorage mechanism and permeability regarding thromboembolism of the LAAO under physiological conditions. A standardized technical and fully parameterized silicone model of a LAA, based on studies of different morphologies and sizes, was developed. The LAA model was mounted onto the left atrial chamber of a commercial pulse duplicator system to simulate physiological hemodynamic conditions. The test was performed using the Watchman device (Boston Scientific, USA; size: 31 mm). The inner implantation diameter of the LAA model was designed according to a target compression of 10% for the Watchman device in the implanted configuration. Furthermore, thrombus-like particles (n=150, d=1,7±0,05 mm) were added to represent the flushing of thrombi out of the LAA after device implantation. Within several cycles it was confirmed that no particles were washed out of the LAA model with the implanted occluder leading to a full protection against thromboembolism. It could also be shown that the occluder is firmly anchored in the LAA. Pressure measurements with sensors in the left atrium and in the LAA distal to the occluder could also show that the occluder has no influence on the pressure conditions in the LAA.
Highlights
The third most frequent cause of death in Germany is stroke with a mortality rate of 8% [1]
The market leader is the Watchman left atrial appendage (LAA) occluder, which currently represents the only device approved by the Food and Drug Administration (FDA) that is available on the US market
It was found that the occluder is firmly anchored in the LAA model and no movement occurred after the number of cycles performed
Summary
The third most frequent cause of death in Germany is stroke with a mortality rate of 8% [1]. Some patients cannot even be treated with oral anticoagulation because it is contraindicated. For this reason, the minimally invasive implantation of a percutaneous LAA occluder is becoming increasingly relevant. An LAA occluder consists of a Nitinol stent structure sealed with a semi-permeable membrane to prevent thromboembolism. There are currently only a few CE approved LAA occluder on the European market available and the number of clinical studies is comparatively low [4,5,6]. The Watchman LAA occluder consists of a nitinol stent which is covered with a polyethylene terephthalate membrane with a pore size of 160 μm. There is currently no standardized test method available for testing the functionality of newly developed occluder devices, in particular for testing the safe anchorage of the occluder in the LAA and for characterizing para-device leakage
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
