THREE-DIMENSIONAL DRUG RELEASE IN THE STENT-POLYMER-WALL-LUMEN OF A BLOOD VESSEL

• Published in: SIAM journal on applied mathematics 2019-01, Vol.79 (5), p.1850-1871
• Main Authors: DELFOUR, MICHEL C., GARON, ANDRÉ, LAMONTAGNE, STEVEN
• Format: Article
• Language: English
• ISSN: 0036-1399; 1095-712X
• DOI: 10.1137/19M1250923

Stents are used in interventional cardiology in order to keep a diseased vessel open. New stents are coated with a medicinal agent that prevents the early reclosing caused by the proliferation of smooth muscle cells (SMC). In order to obtain the desired release kinetics for the SMC-controlling drug during the required therapeutic period, the current strategy focuses on biphasic or possibly polyphasic release from blends of degradable polymers. Blanchet and co-authors introduced a two-parameter ordinary differential equation to accurately characterize the release kinetics from the experimental release curves of Lao and co-authors for neat polymers and polymer blends under infinite sink conditions. From this Garon and Delfour constructed a three-dimensional semiempirical model for the flat polymeric film in a closed vial without fluid circulation where all the parameters can be measured in the laboratory. The object of this paper is the extension of that work to the three-dimensional modeling of drug release from the polymeric coating of a stent of arbitrary pattern to the wall/lumen of a curved blood vessel. The model also takes into account diffusion and metabolization in its wall and diffusion and blood circulation in its lumen. It is a practical tool to theoretically and numerically simulate the three-dimensional drug release from a thin polymeric coating to the aggregated wall and lumen of the blood vessel for design and evaluation.