Abstract: Kounis syndrome is a rare type of acute coronary syndrome caused by coronary spasm with or without atherosclerotic plaque erosion or rupture due to inflammatory factors released by allergic reactions. Due to a lack of awareness, Kounis syndrome is often underdiagnosed. Here, we for the first time report a case of Kounis syndrome induced by anisodamine. A 48-year-old woman presented with upper abdominal pain and vomiting after eating. She was diagnosed with gastrointestinal spasm and intramuscularly injected with 10 mg anisodamine. The patient subsequently developed chest pain and hypotension with erythematous rash. A systemic allergic reaction was diagnosed. Saline solution, promethazine and dexamethasone were administered immediately. A 12-lead electrocardiogram indicated ST-segment elevation in II, III and aVF leads. Emergent coronary angiography was recommended. According to a preoperative electrocardiogram, the ST-segment elevation in the II, III and aVF leads had disappeared. Coronary angiograph revealed no significant coronary stenosis. The patient was diagnosed with Kounis syndrome induced by anisodamine, showing acute ST-segment elevation myocardial infarction due to allergic coronary vasospasm. During the 9-month follow-up, the patient did not receive further anisodamine injections and remained free of chest pain. In conclusion, it is essential for clinicians to be aware of Kounis syndrome because of the wide range of triggers and its potentially fatal evolution if not identified in time.
Keywords: Kounis syndrome, allergic injury, coronary artery vasospasm, anisodamine