Abstract 11027: Mid-Term Outcomes of Graft and Native Vessel Patency after Coronary Artery Bypass Grafting
Background: Controversy remains as to whether to bypass coronary arteries with moderate (50-70%) stenosis. Bypassing a moderately stenotic vessel is considered a risk factor for subsequent graft failure. Currently, mid-term data regarding bypassing a moderate stenosis on graft patency is conflicting. We assessed the hypothesis that bypassing vessels with moderate stenoses results in greater graft failure and progression of native vessel disease compared to bypassing severe (>70% stenosis) disease.
Methods: Baseline and follow-up coronary angiograms at a mean of 21.8 ± 16.6 months (median 20 months) after CABG of 146 patients between January 2004 and 2010 were analyzed by 2 independent & blinded investigators. We compared the patency of grafts used to bypass moderate (n=154) and severe (n=258) stenoses. Patency of moderately stenotic bypassed (n=154) to non-bypassed (n=125) native vessels (on both a within and between-patient basis) was also compared.
Results: This retrospective, single-centre observational study assessed 412 bypassed vessels. Of these, 154 had moderate stenosis and 258 had severe stenosis. 125 non-bypassed moderate vessels were assessed. In the univariate analysis, 81.0% of grafts used to bypass severe stenosis were patent, compared to 70.8% used to bypass moderate stenosis (p=0.02) (Figure 1). Progression of native vessel disease occurred in 55.8% of bypassed moderately stenotic vessels compared to 24.0% of non-bypassed vessels (p<0.01). Multivariate analysis revealed that bypassing moderate stenosis was associated with greater risk of graft occlusion (p=0.02, OR 1.776, CI 1.093 - 2.888) (Figure 2) and bypassed moderate vessel was associated with greater risk of native progression (p<0.001, OR 4.023, CI 2.317 - 6.985).
Conclusion: Bypassing moderate stenosis may not be beneficial as the risk of graft occlusion and native vessel progression is significantly higher.
- © 2011 by American Heart Association, Inc.