Atorvastatin accelerates both neointimal coverage and re-endothelialization after sirolimus-eluting stent implantation in a porcine model: new findings from optical coherence tomography and pathology

BACKGROUND: Delayed vessel healing after drug-eluting stent implantation is thought to be the underlying mechanisms of late stent thrombosis (LST). METHODS AND RESULTS: In the animal model of stenting, 45 minipigs were divided into 3 groups (n=15 each): bare metal stent (BMS), sirolimus-eluting stent (SES), and SES plus atorvastatin treatment (SES+ator). Neointimal coverage and endothelium coverage were evaluated separately by optical coherence tomography (OCT), pathology, and scanning electron microscopy (SEM) at days 7, 14 and 28. OCT showed that SES significantly delayed neointimal coverage compared with BMS and the percentage of uncovered struts in the SES+ator group was significantly decreased on days 7 (42.7±1.3% vs. 56.8±5.7%, P