The implant-free Append system achieved 100% procedural success and complete LAA elimination in a canine model, with invaginated tissue length reducing significantly by 90 days (p<0.05).
Does the Append System safely and effectively eliminate the LAA via mechanical inversion and ligation in a canine model?
The Append system demonstrated feasibility and preliminary safety for implant-free transseptal LAA elimination via invagination and suture ligation in a canine model.
BACKGROUND: Current endovascular strategies for stroke prevention in atrial fibrillation (AF) rely on permanent metallic implants to occlude the Left Atrial Appendage (LAA). However, these implants are associated with risks such as device-related thrombus, peri-device leaks, and embolization. We evaluated the safety and feasibility of a novel, implant-free transcatheter system designed to eliminate the LAA via mechanical inversion and ligation. METHODS: The Append System utilizes a vacuum-assisted tissue grabber to invert the LAA into the left atrium and a ligation assembly to suture the base, preventing evagination. Six canines (mean weight 29.3 ± 2.0 kg) underwent transfemoral LAA invagination. Follow-up assessments included Transesophageal Echocardiography (TEE), Computed Tomography (CT), and histopathology at 30 days (n = 2) and 90 days (n = 4). RESULTS: Procedural success was 100% (6/6) with no hemodynamic instability, pericardial effusion, or mitral valve injury. Despite variable ostial anatomy (mean 18.1 ± 2.2 mm), a single-sized device was effective in all subjects. Follow-up TEE and CT imaging confirmed complete elimination of the LAA lumen in all animals. The invaginated tissue formed an intra-atrial mass that remodeled significantly, reducing in length from 19.3 ± 1.6 mm at baseline to 11.2 ± 2.8 mm at 90 days (p < 0.05). Histopathology demonstrated preserved endothelial integrity, fibrosis, and neovascularization without thrombus formation. CONCLUSIONS: This pre-clinical study demonstrates the feasibility and preliminary safety of the Append system for transseptal LAA elimination. By utilizing invagination and suture ligation, this approach offers a promising potential implant-free alternative for stroke prevention in atrial fibrillation.
Orbach et al. (Fri,) conducted a other in Atrial fibrillation (canine model) (n=6). Append System (transcatheter LAA invagination and ligation) was evaluated on Procedural success. The implant-free Append system achieved 100% procedural success and complete LAA elimination in a canine model, with invaginated tissue length reducing significantly by 90 days (p<0.05).