Anaphylatoxins in dilated cardiomyopathy.

Objects: The aim of the study was to investigate the possible relationship between activation of complement system and thromboembolic complications in dilated cardiomyopathy (DCMP).

Methods: The plasma C3a and C5a concentrations were determined by radioimmunoassay measurement (Amersham International, UK) in 23 patients with DCMP, 9 with hypertrophic cardiomyopathy (HCMP) and 11 healthy volunteers.

Results: The mean C3a concentration was significantly higher in DCMP patients (572 +/- 55 ng ml-1) compared with hypertrophic cardiomyopathy (344 +/- 30 ng ml-1) and with healthy controls (294 +/- 43 ng ml-1) (P < 0.001). There were no significant correlations for C5a concentrations in this group. Mean C3a concentration in DCMP patients with thromboembolic complications (736 +/- 95 ng ml-1) was also significantly higher compared with DCMP patients without these complications (344 +/- 14 ng ml-1) (P < 0.001).

Conclusions: We conclude that anaphylatoxins may play a role in the pathogenesis of thromboembolic complications.