Shaowu Xiao, Mengya Zeng, Junru He, Dabao Xiao, Yuewu Chen
Background: Coronary artery calcification (CAC) signifies advanced atherosclerosis and portends increased cardiovascular risk. Lipoprotein(a) [Lp(a)] is a causal risk factor for atherosclerosis; however, its association with in vivo lesion morphology and clinical outcomes in patients with symptomatic, advanced CAC remains incompletely characterized. Objective: This study aimed to investigate the association between elevated Lp(a) levels and both in vivo lesion morphology and clinical outcomes in this high-risk population. Methods: In this retrospective cohort, 292 patients with intravascular ultrasound(IVUS)-confirmed CAC were stratified into elevated (≥50 mg/dL,n = 77) or low (<50 mg/dL,n = 215) Lp(a) groups. The primary endpoint was major adverse cardiovascular events (MACEs). Associations were assessed via multivariable Cox models adjusted for clinical covariates. Results: Patients in the elevated Lp(a) group presented a greater incidence of aortic valve calcification (p < 0.001). IVUS revealed constrictive remodeling with a smaller lumen and vessel dimensions. During a median follow-up of 17.2 months, the elevated Lp(a) cohort had a significantly higher MACE rate (37.7% vs. 15.8%; adjusted hazard ratio [aHR] 2.60, 95% CI 1.55-4.35, p < 0.001). Elevated Lp(a) independently predicted increased risks of ischemic stroke (aHR 7.14) and in-stent restenosis (aHR 2.78). Conclusion: In symptomatic patients with IVUS-confirmed CAC, elevated Lp(a) identifies a high-risk phenotype characterized by constrictive vascular remodeling and a markedly increased risk of MACEs, driven particularly by ischemic stroke and in-stent restenosis. These findings support the integration of routine Lp(a) testing into the risk stratification of patients with severe CAC, thereby identifying a precise high-risk phenotype that warrants intensified monitoring and represents an ideal target for emerging Lp(a)-lowering therapies.