[Acute myocardial infarction after wasp sting without anaphylactic reaction]

Bites of hymenopterans (bees, wasps and hornets) are very frequent phenomena that can stir up allergical reactions in venom-susceptible patients but that seldom provoke acute myocardial infarction. In the literature we can find case reports of myocardial infarction after bites of hymenopterans, and preceded by an allergic reaction (sometimes with angiographic evidence of undamaged coronary arteries). The pathophysiological determinant seems to be related to the chemical composition of hymenopterans venom, basically made up by vasoactive and thrombogenic substances able to create vasospasm and coronary thrombosis. Our report refers to a 65-year-old male patient without prior cardiological and allergic events who, bitten by a sharm of three bees, complains of an acute large anterior myocardial infarction with angiographic evidence of thrombotic lesion of the proximal left anterior descending artery treated with direct stenting with procedural success, without showing allergical symptoms. The pathophysiological determinant seems to be related to the release of vasoactive amines and thrombogenic substances contained into the hymenopterans venom, the former able to produce vasospasm, the latter able to create diffuse thrombosis. The use of adrenaline itself to counteract the possible systemic allergic reaction appears to advise against the treatment of patients with cardiological symptoms or coronary artery disease and because of its strong vasoactive activity (it leads, in fact, to vasoconstriction) and thrombogenic effects.