Successful Treatment of Kounis Syndrome Type I Presenting as Cardiac Arrest with ST Elevation.

Abstract

To the Editor: Kounis syndrome describes a group of symptoms that manifest as unstable vasospastic or nonvasospastic angina or as acute myocardial infarction. It is triggered by the release of inflammatory mediators after an allergic reaction.[1,2] A 74-year-old man with urinary incontinence was treated with a radical cystectomy using the Mainz pouch procedure and ureteroscopic lithotripsy. He underwent the third infusion of contrast agent (iopromide) for evaluation of pleural effusion in the right lower field of the lung. Two infusions of APCT with Iomeron® (Iomeprol) contrast medium had previously been administered to this patient. The patient did not have a history of allergies or cardiac issues, although he had previously experienced nausea and vomiting as a contrast agent side effect. In this case, the patient did not complain of symptoms during infusion; however, he did lose consciousness after administration of the contrast agent. Initial heart rhythm could not be measured, as an electrocardiogram (ECG) monitoring system was not available at the time. Following transfer to the emergency department, the patient was evaluated and found to be in a deep coma (Glasgow Coma Scale 3 [E1V1M1]), with agonal gasping and pulseless carotid and femoral arteries. The ECG revealed ST elevation in leads II, III, and aVF and ST depression in the precordial lead [Figure 1]. The patient's blood pressure and respiratory rate were not measured and temporary cardiopulmonary arrest occurred. He received basic cardiopulmonary support and, as systolic blood pressure was unknown, an intravenous injection of 1 mg epinephrine, 4 mg chlorpheniramine, and 125 mg methylprednisolone was administered. When evaluated approximately 5 min after collapse, spontaneous circulation and respiration resumed. A cardiac echo examination was urgently performed and hyperkinetic wall motion was observed. After circulatory stabilization, the patient was transferred to the coronary angiography room. No stenosis or obstruction was observed and the patient was diagnosed with vasospasm caused by an allergic reaction to the contrast agent (Kounis syndrome Type I) and subsequently transferred to the Intensive Care Unit. He did not experience any chest pain, ST elevation was not observed on the cardiogram, and creatine phosphokinase and troponin T did not increase during his stay. The patient was discharged on the 5th hospital day. Figure 1 Electrocardiogram showing ST elevation in II, III, and aVF leads, as well as ST depression in the precordial lead. Kounis syndrome is defined as the concurrence of acute coronary syndromes with conditions associated with mast cellactivation, involving interrelated and interacting inflammatory cells, and includes allergic or hypersensitive and anaphylactic or anaphylactoid reactions.[3,4] Two types have been recently described: Type I includes patients with normal coronary arteries and without predisposing factors for coronary artery disease, in whom acute allergic history induces cardiac dysfunction with normal cardiac enzyme and troponin levels; while patients with preexisting atheromatous disease, in whom acute allergic insult may result in plaque rupture or erosion exhibited as acute myocardial infarction, are classified as Type II. Type I could be an indication of endothelial dysfunction or microvascular angina and treatment includes corticosteroids, antihistamines, and vasodilators.[1] Type II patients are treated by application of an acute coronary syndrome protocol and administration of corticosteroids, antihistamines, and vasodilators.[5] To the best of our knowledge, a case of cardiac arrest with ST elevation by contrast agent in a patient with no history of allergies or cardiac problems (Kounis syndrome Type I) is extremely rare. Where cardiac arrest with ST elevation occurs after infusion of a contrast agent in patients with no allergic or cardiac history, treatment with glucocorticoids, antihistamines, and epinephrine for the treatment of Kounis syndrome Type I should be considered. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.