Foam-based Left Atrial Appendage Closure (CLAAS) Device: Evaluation in a Chronic Canine Model

• Published in: Journal of the Society for Cardiovascular Angiography & Interventions 2023-03, Vol.2 (2), p.100555, Article 100555
• Main Authors: Kaplan, Aaron V., Devellian, Carol, Kim, Jamie H., Rotschafer, Jessica, Levine, Andy, Sommer, Robert J., Gray, William A.
• Format: Article
• Language: English
• Subjects: atrial fibrillation; CLAAS; left atrial appendage closure; left atrial appendage occlusion
• ISSN: 2772-9303; 2772-9303
• DOI: 10.1016/j.jscai.2022.100555

The Conformal Left Atrial Appendage System (CLAAS) is a transcatheter implant designed to occlude the left atrial appendage to prevent stroke in patients with nonvalvular atrial fibrillation. The implant incorporates a novel polyurethane polycarbonate-urea foam matrix to enhance device performance. The objective of this study was to characterize the thrombogenicity, sealing, implant integrity, local tissue response, and systemic toxicity of the implant in a healthy canine model. Devices were evaluated in a chronic canine model using echocardiographic and fluoroscopic guidance (n = 8). Postprocedural echocardiographic evaluation was performed at case completion and at 2, 45, 90, and 150 days. Animals were sacrificed at 90 (n = 4) and 150 (n = 4) days. Necropsy included gross, x-ray, and histologic examination. CLAAS implants were implanted in all animals successfully on the basis of fluoroscopic, intracardiac echo, and transthoracic echo criteria. Although 2 animals were noted to have leaks (1 at implantation and 1 at day 90 post procedure before sacrifice), both were of