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Patient-specific design of a soft occluder for the left atrial appendage


3D printing has been used to create a wide variety of anatomical models and tools for procedural planning and training. Yet, the printing of permanent, soft endocardial implants remains challenging because of the need for haemocompatibility and durability of the printed materials. Here, we describe an approach for the rapid prototyping of patient-specific cardiovascular occluders via 3D printing and static moulding of inflatable silicone/polyurethane balloons derived from volume-rendered computed tomography scans. We demonstrate the use of the approach, which provides custom-made implants made of high-quality, durable and haemocompatible elastomeric materials, in the fabrication of devices for occlusion of the left atrial appendage—a structure known to be highly variable in geometry and the primary source of stroke for patients with atrial fibrillation. We describe the design workflow, fabrication and deployment of patient-specific left atrial appendage occluders and, as a proof-of-concept, show their efficacy using 3D-printed anatomical models, in vitro flow loops and an in vivo large animal model.

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Fig. 1: Patient-specific occluder design and deployment.
Fig. 2: Manufacturing patient-specific occluders.
Fig. 3: Highly variable LAA morphologies and fabricated patient-specific balloons.
Fig. 4: Performance of inflated occluders.
Fig. 5: Occlusion performance of patient-specific design.
Fig. 6: Delivery system and deployment method used in this study.
Fig. 7: Large animal in vivo study.

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The authors thank A. A. Amiri Moghadam for advice and support throughout the project. Scanning electron microscopy of this work was carried out in the City University of New York Advanced Science Research Center NanoFabrication Facility.

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Authors and Affiliations



S.S.R., B.M., S.N.D. and J.K.M. designed and supervised the study. S.S.R., B.M. and S.A. contributed to the writing. S.S.R. and S.A. analysed the data and performed the statistical analysis. S.S.R., S.A., H.S., J.A., K.A-F. and S.D.H. fabricated the samples and collected the data. S.S.R., B.M., S.N.D., S.A., L.B., J.K.M. and R.F.S. provided constructive comments and revised and edited the manuscript. All authors discussed the results and commented on the manuscript.

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Correspondence to Simon N. Dunham or Bobak Mosadegh.

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The authors declare no competing financial interests.

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Robinson, S.S., Alaie, S., Sidoti, H. et al. Patient-specific design of a soft occluder for the left atrial appendage. Nat Biomed Eng 2, 8–16 (2018).

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