Abstract
BACKGROUND Fibrous capsules (Fb) in response to cardiovascular implantable electronic devices (CIEDs) including a pacemaker (P) system, can produce patient discomfort and difficulties in revision surgery due to their high compressive strength, potentially via elevated elastic fibers.
OBJECTIVE To determine if biologic extracellular matrix-enveloped CIEDs (PECM) caused differential Fb properties.
METHODS Retrieved Fb (-P and -PECM) from minipigs were subjected to biomechanical (shear oscillation and uniaxial compression) and histological (collagen I and elastin) analyzes.
RESULTS Fb-PECM showed significant decreases compared to Fb-P at: low strain-loss modulus (390 vs. 541 Pa) across angular frequencies, high strain-compressive elastic modulus (1043 vs. 2042 kPa), and elastic fiber content (1.92 vs. 3.15 µg/mg tissue), particularly closer to the implant’s surface (71% vs. 143% relative to skin dermis elastin) and verified with a solid mechanics hyperelasticity with direction-dependent fiber viscoelasticity compression simulation (r2 ≥ 98.9%).
CONCLUSIONS The biocompatible wrap composed of decellularized porcine ECM for CIEDs generated fibrous tissues with less elastic fibers which contributed to a more desirable material mechanics.
Competing Interest Statement
Partial funding was obtained through Aziyo Biologics research grant.
