Intracoronary infusion of mononuclear bone marrow-derived stem cells is associated with a lower plaque burden after four years

Aim: to assess the long-term effects of intracoronary stem cell (sc) infusion following acute myocardial infarction (ami) on the local atherosclerotic process at the site of infusion after four years of follow- up. methods: we evaluated 18 post-ami patients. group 1 consisted of nine patients given an intracoronary injection of autologous mononuclear sc,and group 2 consisted of nine patients given a placebo injection. the plaque count,plaque burden (pb) and coronary calcium score (ccs) were assessed using multislice 64 ct angiography of the coronary tree four years after sc injection. results: the total pb and ccs along the entire coronary segment distal to the site of infusion were significantly lower in the sc group (pb - 702 mm3 vs. 1.465 mm3,p=0.0006; ccs - 295 vs. 796,p< 0.0001). the mean pb per coronary artery was 112.12 mm3±16.82 mm3 for the treated arteries vs. 189.56 mm3±20.98 mm3 for the untreated arteries (p<0.0001),while the mean ccs was 53.12±16.4 vs. 106.43±10.86 (p<0.0001). in the sc group,there were significant differences in the mean pb (87.75 mm3 vs. 112.12 mm2,p= 0.005) and mean ccs (36.87 vs. 53.12,p= 0.04) between the coronary segment infused with sc and the entire coronary artery. conclusions: multislice ct angiography of atheromatous plaques in the coronary tree four years after sc infusion in post-ami patients indicates a significantly lower atheromatous plaque burden,as demonstrated by a lower plaque volume and lower ccs at the site of stem cell infusion compared with other coronary territories.