Type I Kounis Syndrome after Protracted Anaphylaxis and Myocardial Bridge—Brief Literature Review and Case Report

The term allergic angina, introduced for the first time by Nicholas Kounis in 1991, initially referred to the coexistence of acute coronary syndromes with allergy or hypersensitivity. At present, it is believed that Kounis syndrome is a particular case of systemic disease, with multiorgan arterial involvement generated during immediate hypersensitivity reactions. Myocardial bridging (MB), a condition that can induce coronary artery spasm, has long been regarded as a benign condition. Since both pathologies are associated with arterial spasm, Kounis syndrome and MB are considered to be confounding pathologies for acute coronary syndromes, and their association is quite a rare finding. To date, there are no precise data on the epidemiology, and the population affected by Kounis syndrome seems to be highly heterogeneous. Since this is a rare disease, even less is known about possible different phenotypes, including MB overlap. We report a case of type I variant Kounis syndrome associated with MB with no evidence of coronary artery disease, occurring as late presentation, following a severe systemic reaction (anaphylaxis) induced by a Hymenoptera sting. At present, only two other cases of type I and one case of type II Kounis syndrome occurring in patients with myocardial bridging have been described.