 But, there has been no guideline for the duration of dual antiplatelet therapy in ZES although shorter duration of dual antiplatelet therapy could be safe compared to previous drug-eluting stents. Also, there is no data how long duration might be taken in completion of reendothelialization after ZES implantation in living patients. The most powerful histological predictor of stent thrombosis was endothelial coverage. The best morphometric predictor of LST was the ratio of uncovered to total stent struts. Because the presence of endothelization is not available in in vivo situation and endothelialization is reported to be associated with neointimal coverage of stent, the detection of neointima after stent implantation could be the main issue to predict the stent thrombosis. Recent data in SES using optical coherence tomography OCT reported neointimal coverage over a SES at 3-month follow-up is incomplete. The rates of exposed struts and exposed struts with malapposition were 15 and 6, respectively. These were more frequent in patients with acute coronary syndrome ACS than in those with non-ACS 18 vs 13, p 0.0001; 8 vs 5, p 0.005, respectively. 