Higher Lipid Core Burden Index Research Articles

Analysis of saphenous vein graft lesion composition using near-infrared spectroscopy and intravascular ultrasonography with virtual histology

Objective To examine the composition of saphenous vein graft (SVG) lesions using two novel modalities, near-infrared spectroscopy (NIRS) and intravascular ultrasonography with virtual histology (IVUS-VH). Methods We performed NIRS and IVUS-VH imaging of 23 SVGs in 21 patients undergoing clinically-indicated angiography. Results Mean patient and SVG age was 66 ± 7 and 10 ± 7 years, respectively. SVG lesion location was aorto-ostial in 8 (35%), body in 13 (57%) and distal anastomotic in 2 (9%). Compared to anastomotic lesions, body lesions had larger mean lumen area (6.4 ± 1.8 mm 2 vs. 4.2 ± 6.4 mm 2, P = 0.02) but similar mean plaque burden (73 ± 5% vs. 70 ± 10%, P = 0.66). A NIRS lipid core plaque was identified in 9 of 13 body lesions vs. 1 of 10 anastomotic lesions (69% vs. 10%, P = 0.005). SVG body lesions had higher lipid core burden index (LCBI) compared to anastomotic lesions (184 ± 76 vs. 49 ± 54, P < 0.001). By IVUS-VH, SVG lesions had high % necrotic core (28 ± 10%) and % dense calcium (13 ± 10%), without any significant difference between body and anastomotic sites. Older SVG age was associated with higher lesion and vessel LCBI ( r = 0.76 and r = 0.64, respectively, P < 0.001), but was not associated with IVUS-VH determined plaque composition. Higher HDL-cholesterol was associated with lower lesion LCBI ( r = −0.43, P = 0.04). Conclusions NIRS-measured lipid core plaque in SVGs increases with increasing SVG age and is infrequent in anastomotic lesions. No association was found between IVUS-VH plaque composition measurements and SVG lesion location or age.