Abstract: A therapeutic or prophylactic treatment method of acute myocardial infarction, comprising administering exogenous C1-esterase inhibitor, alone or in combination with other drugs, to a patient with acute myocardial infarction or to a patient at risk for acute myocardial infarction. The treatment inhibits the inflammatory reaction, more specifically the activation of the complement system, which occurs in the course of acute myocardial infarction. The C1-esterase inhibitor may include C1-esterase inhibitor purified from plasma or other biological materials, or recombinant C1-esterase inhibitor, or recombinant variants derived therefrom, or recombinant constructs of other inhibitors having a specificity similar to C1-esterase inhibitor.