OBJECTIVES: 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+/-1.8mm(2) vs. 4.2+/-6.4mm(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. Isaac Rochell Authentic Jersey