Abstract 4142588: Increased macrophage activity in non-culprit plaques in patients with acute coronary syndrome and familial hypercholesterolemia

Introduction: Patients with familial hypercholesterolemia (FH) are at a very high risk of recurrent coronary events. However, the characteristics of non-culprit coronary plques in patients with FH remain unclear. Hypothesis: Patients with FH have a higher prevalence of vulnerable non-culprit coronary plaques compared to patients without FH. Methods: A total of 130 patients with acute coronary syndrome (ACS), who underwent optical coherence tomography (OCT) imaging of non-culprit plaques were included. The characteristics of non-culprit plaques were compared between patients with and without FH. Results: A total of 23 patients (8.9%) were clinically diagnosed with FH. The prevalence of macrophages (71.4 vs. 42.0%, p = 0.046) and layered plaques (78.6 vs. 37.8%, p = 0.008) was significantly higher in patients with FH than those without (Panel A) although the prevalence of non-culprit plaques (60.9 vs. 49.2%, p = 0.383) and the severity of stenosis was comparable between the groups (Panel B). The prevalence of plaques with a macrophage grade of 2 or higher (Semi-quantification of macrophages on OCT images: Panel C) was significantly higher in patients with FH than those without (42.9 vs. 16.0%, p = 0.021) (Panel D). Conclusions: Patients with FH had a higher prevalence of macrophages and layered plaque compared with those without FH in non-culprit plaques among patients with ACS. The present results further suggest the importance of FH diagnosis at the time of ACS event and the requirement of intense secondary prevention in patients concomitant with FH.