Effects of peripheral vascular intervention on ischemia-modified albumin

Ischemia-modified albumin was regarded as an early marker of cardiac ischemia. On the other hand, it has been reported that increased ischemia-modified albumin levels are associated with unstable plaque processes like percutaneous coronary intervention, acute coronary syndrome or myocardial infarction. This prospective study aimed to investigate the role of ischemia-modified albumin in patients with peripheral vascular disease undergoing peripheral vascular intervention, a plaque-altering procedure without evidence of tissue ischemia. Peripheral vascular intervention was performed in 21 consecutive patients (68.2 +/- 13.3 years) with typical leg claudication and documented peripheral vascular disease. Additionally, 96 consecutive patients (66 +/- 12.0 years) undergoing routine exercise stress test for the exclusion of functionally relevant coronary artery disease were defined as controls. It was assumed that in the latter patients no unstable plaque-altering processes were present. Blood samples were drawn before, and 30 min and 3 h after, revascularization in the peripheral vascular intervention group, as well as before, and 30 min and 3 h after, maximum stress testing in the control group, respectively. Ischemia-modified albumin levels were analyzed using the albumin cobalt-binding test. In patients undergoing peripheral vascular intervention, ischemia-modified albumin increased from 116.6 +/- 19.1 U/ml at baseline to 132.0 +/- 19.3 U/ml 30 min after intervention (+ 14.4 +/- 15.7%, P < 0.001) and decreased to 123.5 178 U/ml 3 h later (- 5.7 +/- 10.5%, P < 0.001 compared with postintervention, P < 0.001 compared with baseline). The control group showed a slight but significant decrease in ischemia-modified albumin from 103.0 +/- 11.0 to 100.2 +/- 11.6 U/ml poststress (-2.2 +/- 11.5%, P < 0.05) and returned close to baseline 3h later (101.8 +/- 10.3 U/ml, + 2.4 +/- 10.9%, P=NS, compared with poststress and with baseline). For both groups, ischemia-modified albumin showed no correlation with albumin (at baseline P=0.62) and total protein (P=0.67), but significant correlation with creatinine (P=0.04) and C-reactive protein (P=0.02). In addition, ischemia-modified albumin was independent of age, sex, alanine aminotransferase, aspartate aminotransferase, creatine kinase, creatine kinase-MB, cholesterol, and triglycerides. This study showed an increased basal ischemia-modified albumin level in patients with peripheral vascular disease undergoing peripheral vascular intervention. Ischemia-modified albumin levels transiently increased shortly after peripheral vascular intervention, indicating a strong correlation between serum concentration of ischemia-modified albumin and processes associated with acute plaque disruption/rupture.