Why the study?
Non-Lp(a) apoB particles are major determinants of plaque burden while Lp(a) is linked to plaque inflammation and instability, yet how the relative balance between these particle classes relates to coronary plaque phenotype remained incompletely defined.
Does the non-Lp(a) apoB to Lp(a) ratio identify coronary plaque burden and vulnerability features in patients with recent acute myocardial infarction?
Does the non-Lp(a) apoB to Lp(a) ratio identify coronary plaque burden and vulnerability features in patients with recent acute myocardial infarction?
In patients with recent acute myocardial infarction, a low non-Lp(a) apoB to Lp(a) ratio identifies lipid-rich, unstable coronary plaque phenotypes on NIRS-IVUS, while higher non-Lp(a) apoB reflects diffuse atheroma volume.
Background Apolipoprotein B (apoB)-containing lipoproteins contribute heterogeneously to atherosclerosis. While non-lipoprotein(a) [Lp(a)] apoB particles are major determinants of plaque burden, Lp(a) has been linked disproportionately to plaque inflammation and instability. How the relative balance between these particle classes relates to coronary plaque phenotype remains incompletely defined. Objectives To examine the associations of non-Lp(a) apoB, Lp(a), and their ratio with coronary plaque burden and vulnerability using intravascular imaging. Methods This study included 854 participants with recent acute myocardial infarction enrolled in the PROSPECT II near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS) study of vulnerable plaque detection. Total apoB-100 (mg/dL) was converted to nmol/L (×19.49). Because each Lp(a) particle contains one apoB-100 molecule, non-Lp(a) apoB was calculated as total apoB minus Lp(a) (both in nmol/L). The ratio of non-Lp(a) apoB / Lp(a) quantified the relationship of non-Lp(a) apoB particles to Lp(a). Outcomes included plaque percentage volume (PPV), lipid core burden index (LCBI), and vulnerability features defined as maxLCBI4mm≥324.7, plaque burden ≥70%, or both. Multivariable linear and logistic regression models adjusted for demographic and clinical covariates. Results Median [IQR] total apoB was 1358 [1128-1613] nmol/L, Lp(a) 6 [2.5-33.4] nmol/L, and ratio 214 [40-505]. Higher non-Lp(a) apoB was independently associated with greater plaque volume (β=0.19; 95% CI 0.05-0.33; p=0.009) but not with LCBI. Lower non-Lp(a) apoB / Lp(a) ratios were associated with greater plaque burden (OR=1.47; 95% CI 1.04-2.07; p=0.029) and with the composite vulnerability endpoint (OR=1.62; 95% CI 1.12-2.33; p=0.011). Conclusions Non-Lp(a) apoB reflects diffuse atheroma volume, whereas relative Lp(a) predominance, captured by a low non-Lp(a) apoB / Lp(a) ratio, identifies lipid-rich, unstable plaque phenotypes. These findings indicate that the non-Lp(a) apoB/Lp(a) ratio may help differentiate plaque phenotypes in intravascular imaging studies, providing complementary biological information beyond total apoB or LDL-CFigure
No takes yet. Share an insight, caveat, or question.
Tsimikas et al. (2026) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: