Risk factors of venous aortocoronary bypass graft disease noted at late symptom-directed angiographic study.

One hundred and nineteen consecutive patients who had undergone venous aortocoronary bypass surgery 95.1 +/- 46.0 months earlier and in whom symptom-directed late graft angiography was performed were studied. Patients were designated 'controls' if their graft(s) appeared intact or revealed only minimal irregularities; they were designated 'cases' if one or several grafts showed at least 25% stenosis or complete occlusion. Controls and cases did not reveal significant differences in the frequency of classic nonlipoprotein risk factors or medication, including the use of acetylsalicylic acid. In multivariate analysis, significant graft narrowing or occlusion was most strongly related to elevated serum apolipoprotein B and lipoprotein(a) levels, as well as to the age of the grafts.