[Immune complexes in myocardial infarct].

604 patients were investigated with C1q solid phase RIA in regard to circulating immune complexes (CIC) shortly after myocardial infarction. 118 (19.6%) of these 604 patients had CIC, which disappeared in 99 patients (83.7%) or decreased significantly in 9 cases (7.6%) after 2-4 weeks. Only 10 patients (8.3%) showed persisting CIC. 12 parameters assessing clinical features and laboratory data were compared with the results of CIC investigation in altogether 251 patients, of whom 54 (21.5%) were CIC-positive. No differences between CIC-positive and CIC-negative patients were observed with regard to generally accepted factors predisposing to infarction. However, CIC-positive patients differed significantly from CIC-negative cases in the higher incidence of a history of respiratory tract infection before infarction (p less than 0.001) and the more frequent absence of a family history of cardiac and circulatory disease (p less than 0.0005). Interpretation of these results indicates a transient appearance of CIC after liberation of heart - tissue antigens during infarction, but does not exclude the possible existence of a group of patients manifesting CIC already before the onset of infarction, whereby the CIC may have contributed towards triggering off the infarction. In this case persistence of CIC after infarction may be regarded as an unfavourable sign.