Soluble lectin-like oxidized LDL receptor-1 (sLOX-1) as a valuable diagnostic marker for rupture of thin-cap fibroatheroma: verification by optical coherence tomography.

BACKGROUND

Relationships between plaque morphology on optical coherence tomography (OCT) and biomarker levels in the patients with acute coronary syndrome (ACS) have not been fully investigated.

METHODS

ACS patients (n=128) were prospectively enrolled and their plasma levels of soluble lectin-like oxidized LDL receptor-1 (sLOX-1), high-sensitivity C-reactive protein (hs-CRP), and high-sensitivity troponin T (hs-TnT) were measured. Another set of 20 patients with stable angina pectoris (SAP) without plaque rupture or erosion served as controls. Among 128 ACS patients, 75 patients underwent OCT procedure to evaluate culprit plaque morphology, and were categorized into two groups; ACS with plaque rupture (ruptured ACS; R-ACS, n=54) and ACS without plaque rupture (non-ruptured ACS; N-ACS, n=21).

RESULTS

Levels of sLOX-1 (p<0.001), hs-CRP (p=0.048) and hs-TnT (p<0.001) were significantly higher in R-ACS than SAP. Levels of sLOX-1 were also significantly higher in R-ACS than in N-ACS (p<0.001); whereas levels of hs-CRP (p=0.675), as well as those of hs-TnT (p=0.055), were comparable between R-ACS and N-ACS. Comparison of receiver operating characteristic (ROC) curves among sLOX-1, hs-CRP and hs-TnT to differentiate R-ACS from N-ACS revealed that the area under the curve (AUC) values of sLOX-1, hs-CRP and hs-TnT were 0.782, 0.531 and 0.643, respectively. ROC curves, generated for these biomarkers, to differentiate ACS with thin-cap fibroatheroma (TCFA) from those without demonstrated that the AUC values of sLOX-1, hs-CRP and hs-TnT were 0.718, 0.506 and 0.524, respectively.

CONCLUSION

sLOX-1, but not hs-CRP or hs-TnT, can differentiate ACS with plaque rupture from those without, and ACS with TCFA from those without.