Abstract 346: First Demonstration That Low-Density Non-Calcified Plaque on Coronary CT Angiography Correlates With Serum Lipoprotein Values
Background. We have previously published a highly standardized, reproducible, 3D plaque analysis based on CT coronary angiography (CTA). Low-attenuation structures are assumed to be lipoprotein (LP)-rich areas, but their correlation with simultaneously measured serum LP has not been shown.
Methods. 35 patients underwent CTA and intravascular ultrasound with radiofrequency analysis (VH-IVUS). Using our previously validated method, we measured % and volume of lesion compositional parameters (low-density non-calcified plaque [LDNCP], high-density non-calcified plaque [HDNCP], non-calcified plaque [NCP] and calcified plaque [CAP]. LDNCP was defined as pixels with Hounsfield Unit (HU) −100 to +30; HDNCP was 30–150 HU; CAP cutoff was 350 HU. Corresponding structures were measured on VH-IVUS. LP were measured with enzymatic methods; linear correlation analysis was performed.
Results. Higher ApoB-containing particle content and lower HDL-C were associated with higher percentage of LD-NCP, while there was no significant association with CAP or HD-NCP (thought to be fibrous tissue) (Table⇓). Lower HDL-C was associated with more necrotic core on VH-IVUS (r=−0.34; p<0.05).
Conclusions. This is the first demonstration that low-attenuation areas on CTA are associated with serum LP parameters; this provides further evidence that these structures on CTA may represent lipid-rich areas.