Orthopedic Surgery changes Aortic Valve Composition in ApoE-/- mice.

BackgroundIn atherosclerotic cardiovascular disease (ASCVD), acute systemic inflammatory insults such as infections or major surgery are known to trigger cardiovascular events. However, it remains unclear whether such systemic triggers also modulate local inflammatory and degenerative processes within the aortic valve (AV). We therefore investigated the effect of orthopedic surgery on AV remodeling in an atherosclerosis-prone setting.MethodsApoE-/- mice subjected to orthopedic surgery, ApoE-/- controls, and non-atherosclerotic controls were analyzed at 5 and 15 days post-intervention. AVs were assessed for valve thickness, fibrosis, glycosaminoglycans (GAGs), lipid accumulation, calcification, iron deposition, and inflammatory cell infiltration.ResultsAtherosclerotic mice exhibited degenerative AV changes compared to non-atherosclerotic controls. Orthopedic surgery did not affect valve thickness or inflammatory cell infiltration, but induced compositional changes, including increased GAG content at day 5 (56.7 vs. 27.3; p=0.016), a trend toward increased fibrosis at day 15 (41.3 vs. 24.9; p=0.068), and reduced lipid content at day 5 (11.3 vs. 37.3; p=0.008). No differences were observed in calcification or iron deposition.ConclusionOrthopedic surgery induces early compositional remodeling of atherosclerotic aortic valves without increasing inflammatory cell infiltration or valve thickening. These findings suggest a role for systemic inflammatory mediators and matrix-driven remodeling, rather than local inflammatory cell influx, in early valve degeneration.