Saphenous vein graft near-infrared spectroscopy imaging insights from the lipid core plaque association with clinical events near-infrared spectroscopy (ORACLE-NIRS) registry.

Abstract

We sought to examine near-infrared spectroscopy (NIRS) imaging findings of aortocoronary saphenous vein grafts (SVGs). SVGs are prone to develop atherosclerosis similar to native coronary arteries. They have received little study using NIRS. We examined the clinical characteristics and imaging findings from 43 patients who underwent NIRS imaging of 45 SVGs at our institution between 2009 and 2016. The mean patient age was 67 ± 7 years and 98% were men, with high prevalence of diabetes mellitus (56%), hypertension (95%), and dyslipidemia (95%). Mean SVG age was 7 ± 7 years, mean SVG lipid core burden index (LCBI) was 53 ± 60 and mean maxLCBI4 mm was 194 ± 234. Twelve SVGs (27%) had lipid core plaques (2 yellow blocks on the block chemogram), with a higher prevalence in SVGs older than 5 years (46% vs. 5%, P = 0.002). Older SVG age was associated with higher LCBI (r = 0.480, P < 0.001) and higher maxLCBI4 mm (r = 0.567, P < 0.001). On univariate analysis, greater annual total cholesterol exposure was associated with higher SVG LCBI (r = 0.30, P = 0.042) and annual LDL-cholesterol and triglyceride exposure were associated with higher SVG maxLCBI4 mm (LDL-C: r = 0.41, P = 0.020; triglycerides: r = 0.36, P = 0.043). On multivariate analysis, the only independent predictor of SVG LCBI and maxLCBI4mm was SVG age. SVG percutaneous coronary intervention was performed in 63% of the patients. An embolic protection device was used in 96% of SVG PCIs. Periprocedural myocardial infarction occurred in one patient. Older SVG age and greater lipid exposure are associated with higher SVG lipid burden. © 2016 Wiley Periodicals, Inc.