Long-Term Survival is Adversely Affected by Any Use of Saphenous Vein Graft in Coronary Bypass Surgery

Purpose: The predominant technique of coronary bypass grafting (CABG) is a single internal mammary artery and supplementary saphenous vein grafts (SVG). Previous studies have examined an increasing number of arterial conduits; rather than exclusive use of arteries, total arterial revascularisation (TAR). Methods: A single centre experience 1996-2003 for CABG was checked against the national death registry and supplementary investigator follow-up. Overall analysis by the log-rank test (Kaplan-Meier). After exclusion of all incomplete preoperative records and redo CABG, the sample was subjected to Cox proportional hazards survival analysis for any use of SVG; and number of SVG grafts. Results: Overall survival was adversely affected in 8242 participants, p < 0.001 at 14.6 ± 2.2 years postoperative. Absolute differences between groups were small but TAR group had fewer males, more hypercholesterolaemia, family history of ischaemic heart disease, obesity and surgical acuity, whereas the SVG group had more grafts and were older. Following exclusions, Cox proportional hazards analysis found a mortality hazard with any use of SVG to be 1.2 (95% CI 1.1-1.3), p < 0.001. When analysed according to the number of SVG used (referencing SVG n = 0), the mortality hazard for 1 SVG 1.2, 2 SVG 1.4, 3 SVG 1.3, 4 SVG 1.2 and 5 SVG 6.1, with all analyses P≤0.006. Conclusion: The use of even one saphenous vein graft adversely influences survival and more than one worsens survival further compared to total arterial revascularisation.