Two Cases of Kounis Syndrome Caused by Contrast Medium: Early Extracorporeal Membrane Oxygenation

In cardiology, Kounis syndrome (KS), also known as allergic angina or myocardial infarction, is often overlooked in emergencies. Its pathophysiology differs from that of allergic reactions such as anaphylaxis, making differentiation essential. We aimed to report two cases of KS that progressed to cardiac arrest, following the use of contrast medium. In both cases, extracorporeal membrane oxygenation (ECMO) was used for resuscitation, and coronary artery bypass graft surgery was planned for coronary artery reconstruction. ECMO should be considered in severe cases of KS, and clinicians should recognize that contrast-induced KS can be life-threatening.