In particular, the BDNF levels were approximately two times as high in patients with at least two OCT features of plaque vulnerability, compared to those without, in the overall CAD population (group 2–3: 80.88 (21.44–264.4) pg/mL versus group 0–1: 46.67 (10.01–162.8) pg/mL; p = 0.0275), and in patients with SA (group 2–3: 125.8 (35.04–264.4) pg/mL versus group 0–1: 66.32 (19.29–162.8) pg/mL; p = 0.0144) and AMI (group 2–3: 48.2 (21.44–232.2) pg/mL versus group 0–1: 34.18 (10.01–38.27) pg/mL; p = 0.0275), considered separately (Figure 2). Here, BDNF is linked to coronary artery disorder.