Lipoprotein(a) and Adverse Outcomes After Successful Percutaneous Coronary Intervention for Chronic Total Occlusion: A Single-Center Retrospective Cohort Study

Background: Lipoprotein(a) [Lp(a)] is a genetically determined, atherogenic, and prothrombotic lipoprotein. However, its prognostic value in patients who undergo successful chronic total occlusion (CTO) percutaneous coronary intervention (PCI) remains undefined. Methods: This single-center retrospective cohort study included 1509 patients who underwent successful CTO PCI. The primary outcome was cardiovascular death; secondary outcome was major adverse cardiovascular events (MACEs, cardiovascular death or nonfatal myocardial infarction). Multivariable Cox regression and restricted cubic splines (RCS) assessed the association between Lp(a) and outcomes. Results: Over median follow-up of 810 days, 53 (3.5%) cardiovascular deaths and 62 (4.1%) MACEs occurred. Each 1-SD increase in log-transformed Lp(a) was associated with a 51% higher risk of cardiovascular death (aHR 1.51, 95% CI 1.11–2.05, p = 0.008) and a 44% higher risk of MACEs (aHR 1.44, 95% CI 1.09–1.91, p = 0.011). Compared with Lp(a) < 30 mg/dL, Lp(a) ≥ 50 mg/dL conferred a 2.07-fold higher risk of cardiovascular death (95% CI 1.07–4.00, p = 0.029) and a 1.94-fold higher risk of MACEs (95% CI 1.07–3.53, p = 0.030). RCS analysis demonstrated a linear dose–response relationship between log-transformed Lp(a) and both cardiovascular death (p for nonlinearity = 0.653) and MACEs (p for nonlinearity = 0.562). The association was modified by age, hypertension, and left ventricular ejection fraction and remained robust in sensitivity analyses. Conclusions: In patients undergoing successful CTO PCI, elevated Lp(a) was independently and linearly associated with higher risks of cardiovascular death and MACEs. These findings suggest that Lp(a) may serve as a useful prognostic marker to enhance risk stratification in this high-risk population. Large-scale prospective cohorts are needed to validate these findings before clinical translation can be considered.