Drug release in coronary bifurcation stenting

The treatment of coronary bifurcation lesions represents a challenge for the interventional cardiologists due to the lower rate of procedural success and the higher rate of restenosis. The advent of drug eluting stents (DES) has dramatically reduced restenosis and consequently the request for re-intervention [1]. The aim of the present work is to provide further insight about the effectiveness of DES by means of computational analysis that combine virtual stent implantation, fluid dynamics and drug release for different stenting protocols used in the treatment of a coronary artery bifurcation. An explicit dynamic finite element model is developed in order to provide realistic configurations of the implanted device used to perform fluid dynamics analysis by means of a previously developed [2,3] finite element method coupling the blood flow and intramural plasma filtration in rigid arteries. To efficiently model the drug release, a multiscale strategy is adopted, ranging from lumped parameter model accounting for drug release, to fully 3-D models for drug transport to the artery [4]. Differences in drug delivery to the artery are evaluated with respect to local drug dosage. The model allowed to compare alternative stenting configurations thus suggesting guidelines in the treatment of coronary bifurcations lesions and addressing clinical issues such as the effectiveness of drug delivery to lesions in the side branch, as well as the influence of incomplete strut apposition and overlapping stents.