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Published on: May 28, 2019
Kounis syndrome caused by protamine shock after coronary intervention: A case report
Tomonori Itoh1, Yoshinori Kanaya1, Kentaro Komuro1
1Division of Cardiology, Department of Internal Medicine, Memorial Heart Centre, Iwate Medical University, Yahaba, Japan.
Insights
This case report highlights Kounis syndrome, a rare allergic reaction, occurring after protamine administration during percutaneous coronary intervention (PCI). It emphasizes recognizing Kounis syndrome within protamine shock to ensure proper patient management.
Area of Science:
- Cardiology
- Allergy and Immunology
Background:
- Protamine sulfate is used for heparin reversal during percutaneous coronary intervention (PCI).
- Protamine administration can rarely cause anaphylactic reactions, including protamine shock.
Observation:
- A patient undergoing PCI for acute myocardial infarction developed shock following protamine administration.
- Electrocardiography revealed ST-segment elevation and bradycardia, indicative of myocardial ischemia and allergic reaction.
- Coronary angiography demonstrated coronary spasm, and the patient required extracorporeal membrane oxygenation (ECMO).
Findings:
- The patient was diagnosed with protamine shock and Type I Kounis syndrome, an allergic cause of acute coronary syndrome.
- Intradermal testing confirmed hypersensitivity to protamine.
- ST-segment elevation during anaphylactic shock can signify coronary artery spasm.
Implications:
- Kounis syndrome may be an underrecognized complication of protamine shock.
- Clinicians should consider Kounis syndrome in patients presenting with shock after protamine administration.
- Prompt recognition and management are crucial for improving outcomes in these complex cases.
Abstract:
We report a case of Kounis syndrome that led to shock after protamine administration during percutaneous coronary intervention (PCI). A man in his 50s was admitted to the nearest hospital following the onset of acute myocardial infarction. Coronary angiography showed a single-vessel lesion in the left anterior descending artery (LAD). He was admitted for PCI. After heparin administration, the procedure was completed by implantation of a coronary stent with the usual procedure. For hemostasis, following protamine administration, the patient went into shock. Subsequently, electrocardiography showed bradycardia with ST-segment elevation at leads II, III, aVF, and V3-6. Cardiopulmonary resuscitation was started immediately. As pulseless electrical activity continued, extracorporeal membrane oxygenation (ECMO) was introduced. Coronary angiography demonstrated coronary spasm in the LAD. He was withdrawn from the ECMO on day 7. His intradermal tests were positive for protamine in the convalescent phase. The patient was diagnosed with protamine shock and type I Kounis syndrome. Protamine shock is not uncommon, but Kounis syndrome may be hidden in it. Thus, similar cases should not be treated as a simple protamine shock. <Learning objective: This case report aimed to determine 1) the mechanism of protamine shock and its risk factors, and 2) the pathogenesis and type of Kounis syndrome in a patient who developed protamine shock, and 3) the significance of ST-elevation during anaphylactic shock.>.
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