P5625Markers for cholesterol absorption are associated with In-stent-restenosis after coronary stenting in stable coronary artery disease: An Optical Coherence Tomography study

Abstract Background Plant sterols are suspected to exert atherosclerotic propensity. Modern drug-eluting stents are superior to bare metal stents but show a late catch up phenomenon for restenosis. Due to its superb resolution, optical coherence tomography (OCT) has the capability to identify and quantifiy very early patterns of in-stent proliferation. Studies have shown that in-stent neointimal proliferation is linked to late in-stent stenosis. Purpose This study aimed to analyze associations of plasma levels for markers of cholesterol homeostasis such as campesterol and sitosterol (markers for cholesterol absorption) as well as lanosterol (marker for cholesterol synthesis)and and their respective oxides with In-stent restenosis after stent deployment in stable coronary artery disease. Methods Plasma cholesterol was measured by gas chromatography-flame ionization detection. Plasma campesterol, sitosterol and lanosterol and their oxides were analyzed by gas chromatography-mass selective detection. In-stent proliferation (restenosis) was assessed after six months by OCT in 33 patients (21 males). A quantitative OCT algorithm was applied to each stent by steps of one mm and in-stent proliferation volumes and areas were calculated and normalized to stent length and area. In-stent proliferation can be measured by OCT as global volumes and focal areas. Results No clinically significant restenosis or angiographic restenosis of >30% was observed at 6-month f/u. Mean cholesterol level was 166,5±62,8 mg/dl and positively correlated with proliferation volume/cm (r=0.316, p=0.037) and absolute median proliferation area (r=0.322, p=0.029). Absolute median proliferation area and relative median proliferation area correlated positively with markers for cholesterol absorption such as campesterol-to-cholesterol (r=0.277, p=0.07 and 0.315, p=0.037) and sitosterol-to-cholesterol (r=0.237, p=0.092 and 0.322, p=0.034), whereas lanosterol (a marker for cholesterol synthesis) and its ratio to cholesterol correlated negatively with proliferation volumes and areas (p