Correlates of Saphenous Vein Graft Hyperplasia and Occlusion 1 Year After Coronary Artery Bypass Grafting

Abstract

Background— Intimal hyperplasia of saphenous vein grafts (SVGs) can lead to subsequent graft atherosclerosis and occlusion after coronary artery bypass grafting (CABG). This study examined whether patient characteristics, anatomic factors, and medications are associated with SVG intimal hyperplasia and occlusion after CABG. Methods and Results— We performed a post hoc analysis of the Clopidogrel After Surgery for Coronary Artery Disease (CASCADE) trial, where 322 grafts were assessed by angiography and 90 grafts were examined by intravascular ultrasound at 1 year after CABG. We assessed the following correlates for intimal hyperplasia and occlusion: patient characteristics, discharge medications, target vessel characteristics, and SVG diameter. At 1 year, the SVG mean intimal area was 4.3±2.1 mm 2 , and the occlusion rate was 6.2% (13/209). Independent correlates of hyperplasia were larger SVG diameter (1.9±0.2 mm 2 /mm; P <0.001), hypertension (0.7±0.3 mm 2 ; P =0.03), and grafting to the right coronary territory (0.6±0.3 mm 2 ; P =0.03), whereas statin (−0.8±0.3 mm 2 ; P =0.01) and β-blocker use (−1.0±0.4 mm 2 ; P =0.03) were associated with less hyperplasia. Low target vessel quality was an independent correlate of SVG occlusion (odds ratio, 5.2±3.1; P <0.01). Conclusions— Hypertension, SVG diameter, grafting to the right coronary artery, and low quality of the target vessel correlate with the development of SVG hyperplasia or occlusion by 1 year after CABG, whereas β-blockers and statins are associated with less SVG disease. These new findings further our understanding of SVG remodeling after bypass surgery and may guide future research to help prevent post-CABG SVG disease. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00228423

Racial/Ethnic Variation in Carotid Artery Revascularization Utilization and Outcomes

“…Lipid-lowering therapy has been shown to confer short-and long-term benefit after cardiovascular and cerebrovascular procedures for atherosclerotic disease. [31][32][33][34][35] Patients in the blacks group also had a higher incidence of stroke post CEA. Whether the higher incidence of stroke in black patients is related to a lower prescription of aspirin and statins or not, cannot be analyzed by our study.…”

A Randomized Trial of External Stenting for Saphenous Vein Grafts in Coronary Artery Bypass Grafting

“…To date, only persistent use of statin therapy and β blockers have been shown to reduce intimal hyperplasia in SVGs (9) while Edifoligide (8) and aspirin + clopidogrel (10), have both failed to do so, respectively, at 12-18 months after CABG. Mechanical external stents for SVGs have shown considerable promise in pre-clinical testing with reduction of proliferative intimal hyperplasia by reducing wall tension, improving lumen uniformity and creating a protective "neo-adventitia" layer rich with micro vasculature (11)(12)(13).…”

Saphenous vein graft disease, pathophysiology, prevention, and treatment. A review of the literature

“… Endoscopic vs Open LSV harvesting: Minimizing surgical trauma and improvement in patient's quality of life was the driving for the development of endoscopic vein harvesting. However, there is now concern over this technique due to lower long‐term patency rates of LSV grafts retrieved endoscopically 34‐36 Distention: There is a large body of evidence that harvesting and subsequent distention of the LSV at more than 150mm Hg causes endothelial denudation exposing the ECM to the lumen, and increases rates of long‐term graft failure 18,37,38 …”

“…Endoscopic vs Open LSV harvesting: Minimizing surgical trauma and improvement in patient's quality of life was the driving for the development of endoscopic vein harvesting. However, there is now concern over this technique due to lower long‐term patency rates of LSV grafts retrieved endoscopically 34‐36 …”