Article

The effects of stenting on shear stress: relevance to endothelial injury and repair

Biomedical Engineering, Department Cardiology, ErasmusMC, Rotterdam, The Netherlands.
Cardiovascular Research (Impact Factor: 5.81). 04/2013; 99(2). DOI: 10.1093/cvr/cvt090
Source: PubMed

ABSTRACT Stent deployment following balloon angioplasty is used routinely to treat coronary artery disease (CAD). These interventions cause damage and loss of endothelial cells (EC), and thus promote in-stent thrombosis and restenosis. Injured arteries are repaired (intrinsically) by locally-derived EC and by circulating endothelial progenitor cells (EPC) which migrate and proliferate to re-populate denuded regions. However, re-endothelialisation is not always complete and often dysfunctional. Moreover, the molecular and biomechanical mechanisms that control EC repair and function in stented segments are poorly understood. Here we propose that stents modify endothelial repair processes, in part, by altering fluid shear stress, a mechanical force that influences EC migration and proliferation. A more detailed understanding of the biomechanical processes that control endothelial healing would provide a platform for the development of novel therapeutic approaches to minimise damage and promote vascular repair in stented arteries.

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