An Acellular Biologic Extracellular Matrix Envelope for Cardiovascular Implantable Electronic Devices: Preclinical Evaluation

Background: Cardiovascular ?mplantable Electronic Device (CIED) implant sites are prone to fibrotic capsule formation which can lead to device movement, infection risk, and reoperative challenges. Using a biologic CIED envelope at implant may promote constructive tissue remodeling of the pocket and improve outcomes.

Methods: Eleven rabbits received Pacemakers (PMs) in porcine small intestinal submucosa extracellular matrix (SIS ECM) envelopes (PM+ECM) and ten without (PM ONLY). Implant sites were analyzed by observation and histopathology at either week 2, 13, or 26.

Results: PM+ECM animals had a 5-fold reduction in PM subcutaneous movement (device flipping) compared to the PM ONLY group (p=.027). ECM envelopes showed progressive resorption and increasing vascularization at 13 and 26 weeks compared to the PM ONLY group. PM+ECM animals had a lower average capsule thickness compared to the PM ONLY group at 13 and 26 weeks, however the differences were not statistically significant at either time point (p>0.05). Neovascularization scored significantly higher in the PM+ECM group vs. PM ONLY at both 13 and 26 weeks (p=0.046 and p<0.001, respectively).

Conclusion: Use of decellularized ECM envelopes promoted PM implant site healing remarkable for stabilization and increased vascularity, compared to PMs without envelopes in a preclinical model. ECM envelopes may provide meaningful clinical benefits and warrant further investigation.