Immunoglobulin E, mast cell-specific tryptase and the complement system in sudden death from coronary artery thrombosis.

We tested the hypothesis of anaphylaxis as a pathogenic factor in acute myocardial infarction. Mast cells were counted in the myocardium, coronary arteries and airways. Total serum IgE, mast cell tryptase, complements C3, C4, and factor B, were measured in 29 cases of sudden death from coronary artery thrombosis and in 27 controls. We found increased numbers of mast cells in the coronary arteries following coronary death: 46 +/- 21 (SD) compared with 22 +/- 10 (SD) in the control group (P < 0.002). In the myocardium and airways there were no differences between the groups. The concentrations of tryptase and IgE in serum did not differ between the groups although 20% of the coronary deaths had elevated values (> 200 kU/l) compared with 8% in the control group. Of the complement factors, C3 was higher in the coronary deaths (P < 0.05) than in the controls. The results give no evidence of anaphylactic reaction in the pathogenesis of acute myocardial infarction.