OCT-based comparative evaluation of culprit lesion morphology in very young versus older adult patients with STEMI.

Background: The clinical and pathophysiological characteristics of coronary artery disease in very young adults are poorly described.
Aims: Using optical coherence tomography (OCT), we compared culprit lesion morphology in very young adult patients (≤35 years) versus older adult patients (>60 years) with ST-segment elevation myocardial infarction (STEMI).
Methods: Culprit lesion morphology was classified as plaque rupture, plaque erosion, or calcified nodule. Thrombus age was subclassified into acute (intraluminal thrombus with surface irregularity) or subacute (mostly mural thrombus with a smooth surface).
Results: A total of 61 patients who underwent thrombolysis within 24 hours from symptom onset were included, with 38 (59.7%) subjects ≤35 years and 23 (40.3%) subjects >60 years of age. As an underlying mechanism of STEMI thrombosis, plaque erosion was more common in very young patients (52.6% vs 21.7%; p=0.02) while plaque rupture was more common in elderly patients (65.2% vs 36.8%; p=0.03). Acute or subacute thrombus was identified in 68.9% (42/61) of patients, with red thrombus being more frequent in very young patients. In the entire patient cohort, acute thrombus was more frequent in plaque rupture compared with plaque erosion (62.0% vs 28.0%; p=0.01), whereas subacute thrombus was more common in plaque erosion versus plaque rupture (52.0% vs 10.3%; p=0.0008).
Conclusions: OCT showed that plaque erosion and plaque rupture were the most common underlying STEMI mechanisms in very young patients and older patients, respectively, and that subjects with plaque erosion had greater evidence of subacute thrombus.
Competing Interests: A. Maehara reports consultant fees for Abbott, Boston Scientific, Philips, and SpectraWAVE; and speaker honoraria from Nipro. M. Matsumura reports consultant fees from Boston Scientific and Terumo. A. Qamar reports receiving institutional grant support from Novo Nordisk and NorthShore Auxiliary Research Scholar Fund; and fees for educational activities from the American College of Cardiology, Society for Vascular Medicine, Society for Cardiovascular Angiography and Interventions, Johnson & Johnson, Pfizer, Medscape, and Clinical Exercise Physiology Association. G.S. Mintz reports honoraria from Boston Scientific, Philips, Abbott, SpectraWAVE, and Gentuity. Z.A. Ali reports institutional grant support from Abbott, Abiomed, Acist Medical Systems, Amgen, Boston Scientific, CathWorks, Canon, Conavi, HeartFlow, Inari, Medtronic, National Institute of Health, Nipro, Opsens Medical, Medis, Philips, Shockwave Medical, Siemens, SpectraWAVE, and Teleflex Inc; consultant honoraria from Abiomed, AstraZeneca, Boston Scientific, CathWorks, Opsens Medical, Philips, and Shockwave Medical; and equity in Elucid, Lifelink, SpectraWAVE, Shockwave Medical, and VitalConnect. The other authors have no conflicts of interest to declare.