Impact of culprit plaque and atherothrombotic components on incomplete stent apposition in patients with ST-elevation myocardial infarction treated with Everolimus-eluting stents-an OCTAVIA Substudy

Background: The role of culprit plaque and related atherothrombotic components on incomplete stent apposition (ISA) occurrence after primary percutaneous coronary intervention (p-PCI) is unknown. Methods and Results: ST-segment elevation myocardial infarction (STEMI) patients undergoing p-PCI with an everolimus-eluting stent were prospectively investigated with optical coherence tomography (OCT) of the infarctrelated artery before, after stenting and at 9 months. OCT data, aspirated thrombus and serum inflammatory biomarkers were analyzed. 114 patients with 114 lesions were evaluated. Acute ISA occurred in 82 lesions (71.9%), preferentially in larger vessels with a median area of 0.2 mm2. The presence of thrombus before stent implantation (odds ratio (OR) 5.5, 95% confidence interval (CI) [1.1–26.9], P=0.04) and the lipid content in the target segment (OR 1.3, 95% CI [1.0–1.5], P=0.04) independently predicted acute ISA. At 9-month follow-up, ISA persisted in 46 lesions (56.1%). The volume of acute ISA significantly predicted persistent ISA (OR 1.3, 95% CI [1.1–1.5], P=0.01). Late-acquired ISA occurred in 39 lesions (34.2%) with a median area of 0.3 mm2. Red/mixed thrombus before stent implantation (OR 3.7, 95% CI [1.0–13.3], P=0.05) and length of the underlying ruptured plaque (OR 1.7, 95% CI [1.1–2.8] P=0.02) were independently associated with late-acquired ISA. Conclusions: In STEMI patients, culprit plaque and atherothrombotic components of the infarct-related artery significantly contribute to the onset of acute and late ISA. ISA persistence at follow-up depends on the initial volume of acute ISA.