Relationship between elevated levels of serum uric acid and saphenous vein graft disease.

Objectives: Several studies have shown an association between elevated serum uric acid (SUA) levels and coronary heart disease and cardiovascular mortality. We investigated the relationship between SUA levels and the patency of saphenous vein grafts (SVG) after coronary artery bypass graft (CABG) surgery.

Study Design: The study included 192 patients (152 men, 40 women) who underwent elective coronary angiography after a mean of 5.6 years following CABG surgery, which involved the use of at least one SVG. The patients were divided into two groups depending on the extent of SVG patency. Stenosis of 50% or greater within the SVG was accepted as hemodynamically significant. Serum uric acid levels were determined with the enzymatic colorimetric method.

Results: Ninety patients (71 men, 19 women; mean age 62+/-8 years) were found to have patent SVG. Stenotic SVGs were detected in 102 patients (81 men, 21 women; mean age 62+/-10 years). The time interval between surgery and angiography was significantly longer in the stenotic group (p<0.001). Compared to patients without SVG disease, the mean SUA level was significantly higher in patients with SVG disease (4.9+/-1.2 mg/dl vs 5.8+/-1.4 mg/dl; p=0.02). Serum uric acid levels were similar in patients having stenosis in a single vein graft or multiple vein grafts (p=0.224). In multiple regression analysis, SVG disease was independently associated with SUA (p<0.001), diabetes mellitus (p=0.028), and smoking (p=0.039).

Conclusion: Our results show that there is a significant association between increased SUA levels and SVG disease in patients undergoing CABG, which may justify the need for early screening for hyperuricemia and antiuricemic treatment.