Background: The correlations between circulating angiogenic cell mobilizations and improvement of microvascular integrity were investigated in patients (n=110) with acute myocardial infarction (AMI) during an 8-month follow up. Methods and Results: Coronary flow reserve (CFR) was measured at baseline and at 8 months by using an intracoronary Doppler wire. Serial changes in the absolute numbers of circulating angiogenic cells such as CD34+, CXCR4+, CD117+, CD133+ and C-met+ were measured at baseline, day 1, day 5 and at 8 months. The absolute numbers of circulating angiogenic cells at day 1 were significantly higher than those at baseline. A positive correlation was found between the numbers of circulating angiogenic cells of CD34+, CXCR4+, CD117+ and CD133+ cells at day 1 and the CFR changes from baseline. The cut-off value of CFR changes at 8 months by a receiver operating characteristic curve between a circulating CD34+ cell at day 1 and changes of CFR at 8 months was 0. Late-loss showed the positive correlation with the absolute number of C-met+ cells and the negative correlation with the absolute number of CXCR4+ cells after AMI. The negative correlation was found between changes in high-sensitive C-reactive protein and soluble intercellular adhesion molecule-1 and changes in CFR at 8 months. Conclusions: The recovery of microvascular integrity after acute ischemic injury was expedited by the increases in circulating angiogenic cell mobilization together with the greater decreases in inflammatory cytokines. The improvement in CFR could be predicted by the measurement of circulating angiogenic cells after AMI. (Circ J 2012; 76: 1213-1221)