Results:

The mean ± standard deviation patient age was 36 ±15 years and 58% were male. Patients with FM were more likely to present with fever and had lower left ventricular ejection fractions and greater incidences of ventricular dysrhythmias than NFM patients. On histopathology, 19 patients with FM had lymphocytic myocarditis and one had giant cell. Fifteen FM patients had evidence of Coxsackievirus genome on RT-PCR. In the NFM group, eight had lymphocytic myocarditis and five had eosinophilic myocarditis, whereas only three had Coxsackievirus on RT-PCR. Plasma thioredoxin levels were significantly higher on admission in FM patients (3.1 ± 2.2 ng/ml) than NFM (1.6 ± 0.45 ng/ml, ANOVA p = 0.011) and controls (1.8 ± 0.36) as were plasma IL-10, TNF-α, and sTNF-R levels (all ANOVA p < 0.001). There was no significant difference in admission adiponectin levels (FM = 5.1 ± 2.1 ng/ml vs. NFM = 4.9 ± 2.1 ng/ml vs. control = 3.8 ± 0.89 ng/ml, ANOVA p = 0.04). Two weeks after admission, thioredoxin levels significantly dropped in the FM group (1.9 ± 0.62 ng/ml, p = 0.044 compared with admission), but no change was noted in the NFM group. Follow-up sTNF-R levels significantly reduced in both the FM (10.3 ± 1.1 pg/ml to 9.1 ± 1.7 pg/ml, p = 0.011) and NFM groups (7.5 ± 1.5 pg/ml to 5.8 ± 0.69 pg/ml, p = 0.015). No change was noted in adiponectin, IL-10, or TNF-α levels at follow-up. MCS duration was significantly longer in patients who died or required transplant (20 ± 9 days) than that of FM patients who recovered myocardial function (7 ± 5 days, p = 0.002). MCS duration was associated with lower admission systolic blood pressure (odds ratio [OR], 0.86 [0.78-0.94]), higher heart rate (OR, 1.09 [1.03-1.16]), higher admission plasma thioredoxin levels (OR, 5.8 [1.7-20]), and lower admission adiponectin levels (OR, 0.16 [0.055-0.49]).