['Acute or subacute stent thrombosis (ST) is a well-described complication usually causing acute coronary syndromes and, in the worst case scenario, sudden cardiac death. In this study, we aimed at exploring the potential role of optical coherence tomography (OCT) in the understanding of the mechanism of ST.', 'Twenty-one consecutive patients, after acute coronary syndromes due to a definite subacute ST, were assessed with OCT and matched 1:2 with 42 patients undergoing OCT for scheduled follow-up. Optical coherence tomography assessment was focused on features indicative of nonoptimal stent deployment: underexpansion, malapposition, edge dissection, and reference lumen narrowing.', 'Optical coherence tomography revealed a minimum stent area sensibly smaller in the ST group (5.6 ± 2.6 vs 6.8 ± 1.7 mm(2); P = .03) with a higher incidence of stent underexpansion when compared with the control group (42.8% vs 16.7%; P = .05). Dissection at stent edges was more commonly detected in ST group (52.4% vs 9.5%; P < .01). No significant differences between the 2 groups were observed for malapposition (52.4% vs 38.1%; P = .651) and reference lumen narrowing (19.0% vs 4.8%; P = .172). At least 1 OCT finding indicative of suboptimal stent deployment was detectable in 95.2% of patients experiencing ST versus 42.9% of the control group (P < .01).'] Is suboptimal stent deployment associated with subacute stent thrombosis : optical coherence tomography insights from a multicenter matched study . From the CLI Foundation investigators : the CLI-THRO study?