Background

Intramyocardial inflammation is considered as an adverse prognostic factor in inflammatory cardiomyopathy (DCMi). However, the precise nature of immune cells relevant for the prediction of long-term course remains elusive. We analyzed the correlation of increased t cell inflammatory infiltrates (CD45RO - activated memory T lymphocytes, CD3) to mortality in a large cohort of patients with DCMi.

Methods

We investigated 1811 consecutive patients with suspected CMi, undergoing endomyocardial biopsies (EMBs), and examined the mortality of these patients for a 10-year follow-up period. In EMBs myocardial inflammation was assessed by histology and immunohistology including digital imaging analysis. In total, 82 (4.5 %) patients met the endpoint of death (31.9 ± 21.8 months).

Results

Statistical analysis of mortality in all patients revealed that a high number of CD45RO or CD3 cells in EMBs at the point of the initial biopsy is an important predictor of mortality (9.3%/10.5% respectively). The analyzed cohort was divided by the number of measured CD45RO cell number higher than 50/60 cells/mm² myocardial tissue with an increasing rate of mortality and significance (p=0.0001/ p=0.0002). For CD3 positive lymphocytes the mortality is significantly higher starting from a cell number higher than 20 cells/mm² (p<0.0004).

Conclusion

In this EMB-based analysis of the long-term course of DCMi we identified, for the first time, that high numbers of CD45RO and CD3 positive inflammatory cells in the myocardium predict increased mortality.