Effect of aortic pulse and fractional pulse pressures on early patency of sapheneous vein grafts

Abstract

Background: Coronary artery bypass grafting has a mortality benefit compared to medical therapy in some patient groups, such as those with left main or left anterior descending coronary artery disease, and those with left ventricular dysfunction. Therefore, patency of grafts, especially sapheneous grafts, is an important issue. Aortic pulse and fractional pulse pressures are strong and independent indicators of the risk of atherosclerosis. We studied whether there was any negative effect of increased aortic pulse and fractional pulse pressures on saphenous vein graft (SVG) patency in the short term.

Methods: We evaluated aortic pulse and fractional pulse pressures of patients with occluded and patent SVGs, and investigated the relation between the two groups. One hundred and twenty-six patients with occluded SVGs with a mean age of 65.9+/-8.9 years and 114 patients with patent SVGs with a mean age of 66.9+/-8.6 years were studied consecutively. Aortic systolic and diastolic pressures were measured, and mean, pulse, and fractional pulse pressures (aortic pulse pressure/mean pressure) were calculated.

Results: Aortic pulse and fractional pulse pressures were significantly higher in the occluded SVG group than in the patent SVG group (58+/-19 and 48+/-13 mmHg, P=0.001; 0.59+/-0.16 and 0.50+/-0.10, P<0.001, respectively). In addition, a cut-off value of 50 mmHg and 0.52 for aortic pulse and fractional pulse pressures were determined, respectively. Increased aortic pulse (>50 mmHg) and fractional pulse (>0.52) pressures were present in 54.0 and 58.7% of patients in group 1 and 28.1 and 33.3% of patients in group 2, respectively (P=0.004 and P=0.005, respectively). Having increased aortic pulse and fractional pulse pressures increased the risk of SVG occlusion by 3.00 and 2.85-folds, respectively. The multiple-adjusted odds ratio of the risk of SVG occlusion was 6.86 (95% confidence interval 2.14-21.96) and 4.76 (95% confidence interval 1.58-14.30) for the higher aortic pulse and fractional pulse pressure levels compared with lower levels, respectively.

Conclusion: Increased ascending aorta pulse and fractional pulse pressures have a significant and independent negative effect on the fate of SVGs.