Drug-Eluting Stents ; Stents/adverse effects* ; Treatment Outcome

Drug-Eluting Stents ; adverse effects ; Humans ; Male ; Middle Aged ; Myocardial Infarction ; diagnosis ; etiology ; Thrombosis ; etiology ; physiopathology

Coronary Restenosis ; therapy ; Drug-Eluting Stents ; adverse effects ; Humans ; Treatment Outcome

BACKGROUNDDrug-eluting stents represent a major advance in interventional cardiology. However, the current drug-eluting stents have significant limitations. One of the major problems is very late stent thrombosis, which is likely caused by inflammation and a hypersensitivity reaction related to a polymer on the stent. A polymer-free sirolimus-eluting stent with a unique nano-porous surface has been developed. This study aimed to evaluate this novel polymer-free sirolimus-eluting stent for its efficacy and safety in a pig model.

METHODSStents were directly coated with sirolimus (a drug concentration of 2.2 µg/mm(2) on the stent surface). The polymer-free sirolimus-eluting stents (PFSES) were compared to standard polymer-coated sirolimus-eluting stents (PCSES) and bare-metal stents (BMS) in 18 pigs.

RESULTSAt one month the degree of neointimal hyperplasia was similar between the two sirolimus-eluting stent groups and was significantly less compared to BMS ((1.93 ± 0.51) mm(2), (1.57 ± 0.69) mm(2) vs. (4.45 ± 1.05) mm(2), P < 0.05) At three months, PFSES maintained the low level of neointima ((2.41 ± 0.99) mm(2) vs. (4.32 ± 1.16) mm(2), P < 0.05), whereas PCSES had developed significant neointimal proliferation similar to BMS. The inflammation level was significantly higher in PCSES when compared with BMS three months post-implantation (2.50 ± 0.55 vs. 0.83 ± 0.75, P < 0.05) whereas PFSES showed a low level of inflammation comparable to PCSES (1.33 ± 0.52 vs. 2.50 ± 0.55, P < 0.05).

CONCLUSIONThe PFSES is effective and safe, and appears to be superior to standard PCSEs.

Animals ; Drug-Eluting Stents ; adverse effects ; Neointima ; prevention & control ; Polymers ; chemistry ; Sirolimus ; therapeutic use ; Swine

Angioplasty, Balloon, Coronary ; adverse effects ; methods ; Drug-Eluting Stents ; Humans ; Paclitaxel ; therapeutic use

Drug-Eluting Stents ; adverse effects ; Humans ; Male ; Middle Aged ; Prosthesis Failure ; Thrombosis ; etiology

Drug-Eluting Stents ; adverse effects ; Humans ; Male ; Middle Aged ; Thrombosis ; etiology

Adult ; Coronary Aneurysm ; etiology ; Drug-Eluting Stents ; adverse effects ; Humans ; Male ; Paclitaxel ; therapeutic use

Drug-Eluting Stents ; adverse effects ; Humans ; Middle Aged ; Myocardial Infarction ; etiology ; Sirolimus ; administration & dosage ; Thrombosis ; etiology

Aged ; Angioplasty, Balloon, Coronary ; adverse effects ; Drug-Eluting Stents ; adverse effects ; Humans ; Male ; Plaque, Atherosclerotic ; complications ; Rupture ; Thrombosis ; complications