Viral genome changes and the impact of viral genome persistence in myocardium of patients with inflammatory cardiomyopathy.

INTRODUCTION

Viral infections are considered the most frequent cause of myocarditis and dilated cardiomyopathy (DCM).

MATERIAL AND METHODS

We investigated the changes in viral presence and the impact of viral genome persistence in the myocardium on echocardiographic parameters, functional status and some laboratory parameters in a 6-month follow-up. Fifty-four patients with recent onset DCM, left ventricular ejection fraction < 40% and biopsy-proven myocarditis (> 14 mononuclear leukocytes/mm and/or > 7 T-lymphocytes/mm) were enrolled. Polymerase chain reaction (PCR) was performed to detect pathogens in the myocardium. Patients were divided according to the administered therapy: standard heart failure medication (46 patients) and immunosuppressive therapy (8 patients).

RESULTS

In the standard heart failure medication group viral clearance was observed in 13 patients and viral persistence in 24 patients in the follow-up period. Comparing both groups, there was no statistically significant difference - LVEF improvement of 12.0 ±11.4% vs. 18.3 ±12.6%, decrease in NYHA class of 0.7 ±0.7 vs. 1.0 ±0.7, decline in NT-proBNP of 1335 ±1933 ng/l vs. 1942 ±3242 ng/l and decrease in infiltrating leukocytes of 11.1 ±15.8 vs. 6.7 ±23.0 cells/mm and T-lymphocytes of 5.8 ±15.1 vs. 1.8 ±10.9 cells/mm (all = NS). A decrease in PCR positive patients from 37 to 29 was observed. The number of PVB19 positive PCR findings decreased from 5 to 4 in patients with immunosuppressive therapy.

CONCLUSIONS

A decrease in the number of positive PCR findings in control endomyocardial biopsy was observed. Viral genome persistence was not associated with worse outcome in short-term follow-up.