## 3 Results
### Polyamine Levels in Peripheral Blood Cells and Plasma for Patients and the Control Group  
Comparing the polyamine levels in mononuclear cells between the control group and patients with AMI and CHF patients, the Kruskal-Wallis test revealed significant differences between the groups for putrescine and isoamylamine (\(p<0.001\)). Pairwise comparisons indicated lower putrescine levels in patients with AMI than the controls (\(p<0.001\)) and CHF patients (\(p=0.04\)) and higher isoamylamine levels in CHF patients than in the control group (\(p<0.001\)) and AMI patients (\(p=0.018\)). The comparison of the control subgroup matched for age with the CHF patient group showed the same significant differences for these amines as the control group using the Mann-Whitney test. No significant differences were found for the remaining amines examined in the blood cells and plasma (Figure 2; Supplementary Table S1). Figure 1: Discriminant function analysis of control subjects, patients with acute myocardial infarction (AMI), and those with chronic heart failure (CHF). Figure 2: Box-and-whisker plots showing the levels (pmol/mg of protein) of putrescine (**a**) and isoamylamine (**b**) in peripheral blood mononuclear cells from the control group and from patients with acute myocardial infarction (AMI) or chronic heart failure (CHF). Control–CHF: Control subgroup matched for age with CHF patients. ***\(p\leq 0.001\) compared to the control group, \(\Phi\)\(p\leq 0.05\) compared to the patients with AMI using the Kruskal–Wallis test. Regarding polyamine levels in erythrocytes (Figure 3; Supplementary Table S1) and plasma (Figure 4; Supplementary Table S1), the Kruskal-Wallis test showed significant differences between the groups (\(p<0.001\)) for putrescine, spermidine, spermine, N-acetyl putrescine, and N-acetyl spermidine. Pairwise comparisons revealed that the levels of all these amines were significantly lower in patients with CHF than in the control group (\(p<0.001\)). No significant differences were observed when comparing the AMI patients to the control group. Regarding isoamylamine, the levels were higher in erythrocytes (Figure 3) and plasma (Figure 4) in patients with AMI than control groups or patients with CHF. The statistical significance of the levels of these amines in the erythrocytes and plasma of the control subgroup matched for age with the CHF group compared to CHF patients showed the same \(p\)-value using the Mann-Whitney test as the control group. The AMI group included 5 NSTEMI and 20 STEMI patients. The Mann-Whitney test revealed no significant differences in their polyamine levels; thus, they were treated as a unique group. Figure 3: Box-and-whisker plots showing the levels of putrescine (**a**), spermidine (**b**), spermine (**c**), N-acetyl putrescine (**d**), N-acetyl spermidine (**e**) (pmol/mg of protein), and isoamylamine (**f**) (nmol/mg of protein) in peripheral blood erythrocytes from the control group and from patients with acute myocardial infarction (AMI) or chronic heart failure (CHF). Control–CHF: Control subgroup matched for age with CHF patients. ***\(p\leq 0.001\) compared to the control group and \(\$\$\$\)\(p\leq 0.001\) compared to patients with AMI vs. CHF using the Kruskal–Wallis test. Correlation Between Polyamines in Peripheral Blood Cells and Plasma and the Clinical and Analytical Parameters of the Patients  
In patients with AMI, diastolic pressure showed a positive correlation with putrescine levels in mononuclear cells (\(r_{s}=0.431\), \(p=0.035\), \(n=24\)). LVEF also exhibited a positive correlation with putrescine (\(r_{s}=0.438\), \(p=0.032\), \(n=24\)), spermine (\(r_{s}=0.456\), \(p=0.025\), \(n=24\)), and isoamylamine levels in mononuclear cells (\(r_{s}=0.412\), \(p=0.045\), \(n=24\)). In addition, LVEF correlated positively with isoamylamine levels in erythrocytes (\(r_{s}=0.509\), \(p=0.011\), \(n=24\)).