Impact of n-3 polyunsaturated fatty acids in predicting ischemia/reperfusion injury and progression of myocardial damage after reperfusion in patients with ST-segment elevation acute myocardial infarction

BackgroundIn animal models of acute myocardial infarction, n-3 polyunsaturated fatty acids (PUFAs) administered before coronary occlusion have been suggested to prevent induction of ventricular arrhythmia and limit infarct size. However, the relation between the serum levels of n-3 PUFAs and ischemia/reperfusion (I/R) injury remains unclear.Methods211 patients with ST-segment elevation acute myocardial infarction received emergency percutaneous coronary intervention (PCI) within 6 h from the onset. The patients were divided into two groups according to the sum of serum eicosapentaenoic acid (EPA) levels and docosahexaenoic acid (DHA) levels before PCI: group L (n = 106), EPA + DHA <155 μg/ml and group H (n = 105), EPA + DHA ≥155 μg/ml. The Selvester QRS-scoring system was used to estimate the serial change in infarct size.ResultsTime to reperfusion was similar between the 2 groups. The QRS score before PCI was higher in group L than in group H (2.42 ± 2.00 vs 1.85 ± 2.01, p = 0.015). The proportion of patients with I/R injury immediately after reperfusion, defined as reperfusion ventricular arrhythmias (25% vs 11%, p = 0.006) and ST-segment re-elevation (44% vs 22%, p < 0.001), was also higher in group L than in group H, followed by a greater increment in the QRS score during PCI (3.51 ± 2.51 vs 2.54 ± 1.91, p = 0.006) and higher peak levels of creatinine phosphokinase (3552 ± 241 U/L vs 2660 ± 242 U/L, p < 0.01). On multivariate analysis, serum level of EPA + DHA was an independent predictor of reperfusion injury (odds ratio 0.985, p = 0.032).ConclusionSerum level of n-3 PUFAs before PCI may be a predictor of I/R injury and the resultant extent of myocardial damage. These findings suggest a protective effect of serum n-3 PUFAs on ischemic myocardium.