Abstract 10174: Smaller Graft Diameter and Beta-Blocker Use are Protective Against Intimal Hyperplasia of Saphenous Vein Grafts at 1 Year after Coronary Artery Bypass Grafting: Analysis from the Cascade Randomized Trial
Background: Intimal hyperplasia of saphenous vein (SV) grafts can lead to subsequent graft atherosclerosis and occlusion after coronary artery bypass grafting. The CASCADE randomized controlled trial was designed to assesse whether clopidgrel was protective against SV graft hyperplasia and occlusion, assessed by 1-year angiography supplemented with intravascular ultrasound (IVUS). The CASCADE trial reported that consistent statin use was significantly associated with a reduction in intimal hyperplasia of SV grafts, and diabetes constituted a risk factor. The present analyses examined whether hemodynamic parameters, medications, and anatomical factors also have an impact on hyperplasia of SV grafts.
Methods: We conducted a post-hoc analysis of the CASCADE trial, where 323 grafts were assessed by angiography at 1 year postoperatively. To assess risk factors for SV graft intimal hyperplasia, we examined the following factors : preoperative demographics, systolic blood pressure (BP), diastolic BP, mean BP, and resting heart rate at 1 year follow-up, medication profile, % stenosis of native target coronary, target vessel location, target vessel quality, target vessel size, and SV diameter.
Results: The mean area of SV graft intimal hyperplasia at 1 year was 4.31±2.06 mm2. Univariate analysis indicated that SV diameter and grafting of the right coronary artery (1.03±0.43 mm2; p=0.019) significantly correlated with the area of SV graft intimal hyperplasia. There was no significant relationship with BP. In multivariate stepwise linear regression analysis, independent predictors of hyperplasia were SV diameter (2.09±0.18 mm2/mm; p<0.001) and beta-blocker use at discharge (-0.96±0.48 mm2; p=0.047).
Conclusions: Anatomical and pharmacological factors had a significant impact on SV graft hyperplasia at 1 year postoperatively. Smaller SV grafts and use of beta-blocker were protective against SV graft intimal hyperplasia, while blood pressure control was not. These findings may help prevent late saphenous vein graft failure and optimize the long-term outcomes of CABG.
- © 2012 by American Heart Association, Inc.