BACKGROUND: The angiotensin-converting enzyme inhibitor ramiprilat has been previously demonstrated to protect myocardium from ischemia/reperfusion injury. OBJECTIVES: The aim of this study was to examine the effects on the arterial healing and anti-proliferative and anti-inflammatory effects of ramiprilat-coated stent in a porcine coronary overstretch restenosis model. METHODS: Pigs were randomized into two groups in which the coronary arteries (16 pigs, 16 coronaries in each group) had either a ramiprilat-coated MAC stent or control MAC stent (AMG, Munich, Germany). Stents were deployed with oversizing (stent/artery ratio 1.3:1) in porcine coronary arteries, and histopathologic analysis was assessed at 28 days after stenting. RESULTS: There were no significant differences in the neointima area normalized to injury score and inflammation score between the two groups (1.58짹0.43, 1.60짹0.39 in ramiprilat stent group vs. 1.60짹0.57, 1.62짹0.49 in control stent group, respectively). Fibrin score was significantly lower (0.10짹0.31 vs. 0.48짹0.57, p=0.002), and there was a strong trend towards smaller neointima area (1.06짹0.51 mm2 vs. 1.28짹0.35 mm2, p=0.083) and percent area stenosis (18.9짹8.7% vs. 22.8짹7.2%, p=0.088) in the ramiprilat stent group compared with control stent group. In neointima, overall, most inflammatory cells were lymphohistiocytes, and lymphohistiocyte count was not significantly different between ramiprilat stent and control stent groups (170짹121 cells vs. 162짹83 cells). CONCLUSIONS: Ramiprilat-coated stent showed beneficial effect on arterial healing and a strong trend toward more inhibition of neointimal hyperplasia with same degree of inflammatory cell infiltration compared with control bare-metal stent in a porcine coronary restenosis model.