Using Oxidized Low-Density Lipoprotein Autoantibodies to Predict Restenosis after Balloon Angioplasty in Patients with Acute Myocardial Infarction

Abstract

Objectives: Oxidized low-density lipoproteins (oxLDL) and oxidized low-density lipoprotein autoantibodies (OLAB) have been detected in human plasma and atherosclerotic lesions. OLAB appear to play a role in the clearance of oxLDL from circulation. Higher levels of OLAB appear to be associated with a reduced risk of a wide range of cardiovascular diseases. We investigated the prognostic value of plasma oxLDL and OLAB in patients undergoing primary coronary balloon angioplasty for acute ST-elevation myocardial infarction (STEMI). Methods: Plasma oxLDL and OLAB concentrations were measured in 56 patients with acute STEMI before primary angioplasty, and then 3 days, 7 days and 1 month after the acute event. Follow-up angiography was repeated 6 months later to detect the presence of restensosis (defined as >50% luminal diameter stenosis). The thrombolysis in myocardial infarction (TIMI) risk score was calculated to determine the relationship between OLAB/oxLDL ratio and TIMI risk scores. Results: Of the 56 patients, 18 (31%) had angiographic evidence of restenosis. Plasma OLAB concentrations were significantly lower in the restenosis group before angioplasty (181 +/- 114 vs. 335 +/- 257 U/L, p = 0.003), and at day 3 (155 +/- 92 vs. 277 +/- 185 U/L, p<0.001) and day 7 (177 +/- 110 vs. 352 +/- 279 U/L, p<0.001) after the acute event. There was no difference in oxLDL concentration between the two groups. The ratio of OLAB/oxLDL positively correlated with TIMI risk scores before angioplasty (p for trend analysis, p = 0.004), at day 3 (p = 0.008) and day 7 (p<0.001) after STEMI. Significance: A relative deficit of OLAB, and hence likely impaired clearance of oxLDL, is associated with the risk of arterial restenosis after primary angioplasty for acute STEMI.