Elevated levels of low-density lipoprotein cholesterol, homocysteine, and lipoprotein(a) are associated with the occurrence of symptomatic bypass graft disease 1 year following coronary artery bypass graft surgery.

Abstract

Severe coronary artery bypass graft disease occurs at a rate of approximately 16%-31% within the first year of surgery. Clinical and laboratory variables, including postoperative lipid profiles closest to the 1-year follow-up, lipoprotein(a) levels, and homocysteine levels, were assessed as predictors of early (< or = 1 year) symptomatic coronary artery bypass graft disease. Of 77 living consecutive patients (from the practice of one cardiologist) who underwent bypass surgery, 60 were asymptomatic at 1 year, and 17 had developed recurrent symptoms and had an angiogram that confirmed >50% lesion in at least one saphenous bypass graft. Using multivariate analysis, the strongest predictors of early symptomatic coronary artery bypass graft disease within 1 year of bypass surgery were elevated levels of low-density lipoprotein cholesterol (>100 mg/dL) (odds ratio [OR], 8:1; p=0.034), homocysteine (>10 micromol/L) (OR, 8:1; p=0.019), and lipoprotein(a) (>30 mg/dL) (OR, 4:1; p=0.011). Male gender was associated with a reduced risk (OR, 1:9; p=0.01) of symptomatic graft disease within 1 year of surgery. The authors conclude that low-density lipoprotein, homocysteine, and lipoprotein(a) levels are associated with symptomatic coronary artery bypass graft disease at 1 year after surgery.