Increased plasma thioredoxin in patients with acute myocardial infarction.

BACKGROUND AND HYPOTHESIS: Thioredoxin is an important biomarker for oxidative stress. We investigated whether thioredoxin levels were elevated in patients with acute myocardial infarction (AMI) and were associated with the results of coronary reperfusion. METHODS: The present study determined plasma thioredoxin levels in 51 patients with AMI, 30 patients with stable exertional angina (SEA), and 30 patients with chest pain syndrome (CPS). Plasma sampling was performed on admission, at 12 h, 1 week, 2 weeks, and 4 weeks in patients with AMI, and after admission in patients with SEA and CPS. RESULTS: Plasma thioredoxin levels on admission were higher in patients with AMI than in those with SEA and CPS. Plasma thioredoxin levels in patients with AMI were decreased in 12 h without further change thereafter. However, thioredoxin levels in patients with AMI remained higher than in those with SEA. In multivariate analysis, higher levels of thioredoxin on admission were a risk factor for failure in emergent reperfusion therapy in patients with AMI independent of other factors. CONCLUSION: Plasma thioredoxin levels are elevated in patients with AMI, and higher thioredoxin levels may predict subsequent failed coronary reperfusion therapy in patients with AMI.

Increased serum matrix metalloproteinase-1 concentration predicts advanced left ventricular remodeling in patients with acute myocardial infarction.

The left ventricular ejection fraction (LVEF) is one of the major prognostic factors after acute myocardial infarction (AMI) and matrix metalloproteinase-1 (MMP-1) is an enzyme responsible for extracellular collagen degradation and remodeling. The present study investigated whether the concentration of serum MMP-1 was associated with the LVEF after AMI. Blood was sampled on admission, and at 24 h, 3 days, 7 days, 2 weeks and 4 weeks in 24 patients with their first AMI. Left ventriculography was performed 4 weeks after the onset of AMI and the LVEF was calculated by center line method. MMP-1 concentrations were higher at 7 days and at 2 weeks than on admission (p<0.001), and at 7 days (r=-0.655, p=0.0005) and at 2 weeks (r=-0.636, p=0.0008) were negatively correlated with the LVEF. The patients with AMI were divided into high and low LVEF groups according to the results of left ventriculography. Although there were no differences in the clinical characteristics between the 2 LVEF groups, the MMP-1 concentrations at 24 h (p<0.01), 7 days (p<0.01) and 2 weeks (p<0.05) were lower in the high LVEF group than in low LVEF group. A high concentration of MMP-1 at the subacute phase after AMI predicts advanced left ventricular remodeling.

Comparison of urinary biopyrrin levels in acute myocardial infarction (after reperfusion therapy) versus stable angina pectoris and their usefulness in predicting subsequent cardiac events.

We examined the relation between oxidative stress and cardiac events in patients with acute myocardial infarction (AMI). There is now increasing evidence that reactive oxygen species cause reperfusion injury to the previously ischemic myocardium after reperfusion. We measured urinary biopyrrin/creatinine levels, an oxidative stress marker, in 41 patients with AMI, 34 patients with stable angina pectoris (SAP), and 29 control subjects. In the patients with AMI, urine samples were taken before, at 4 and 24 hours, and at 1 and 2 weeks after reperfusion therapy. Of these 41 patients with AMI, 38 received reperfusion therapy, and the urinary biopyrrin/creatinine levels (micromol/g.creatinine) before reperfusion were significantly higher than those of the other 2 groups (AMI 4.24 +/- 0.49, SAP 2.45 +/- 0.15, control subjects 2.31 +/- 0.16; p = 0.0003 vs AMI). The onset of reperfusion significantly increased the levels of urinary biopyrrins/creatinine, and this time course was mapped out, peaking at 4 hours (8.21 +/- 0.96 vs 4.24 +/- 0.49 before, p = 0.0001), and decreasing to control levels between 24 hours and 7 days. The peak levels of urinary biopyrrins/creatinine were higher in the positive cardiac event group than in the negative cardiac event group (11.89 +/- 1.77 vs 7.57 +/- 1.00 micromol/g.creatinine, p = 0.029). These findings add further evidence that oxidative stress contributes to the complications of reperfusion injury, and suggest that urinary assessment of biopyrrins may be useful in predicting subsequent cardiac events after reperfusion in AMI.