P728 Left main coronary artery thrombus found in a teenager with Kawasaki disease following cardiac arrest

Abstract

Abstract Background A male teenager presented with an out of hospital cardiac arrest while exercising requiring CPR and DC Cardioversion. Incidentally, he was stung by a wasp minutes before the event. After being admitted, the patient was intubated, ventilated and treated for anaphylaxis and seizures. The patient had no significant past medical or family history of note. Investigations were performed after the patient was stabilized including 15 lead ECG, 24 hours ECG monitor, Echocardiogram and blood sample for troponins and cardiomyopathy screening. The ECG and 24 Hours ECG were reported as normal. The patient also had an exercise treadmill test which showed ischaemic changes at peak exercise. Cardiomyopathy screening was negative. Echocardiogram showed globally mildly impaired left ventricular systolic function with no other significant abnormalities. The patient underwent a cardiac MRI a couple of weeks later which showed an aneurysmal and tortuous proximal left coronary artery with a thrombus and also an aneurysmal mid left circumflex artery. Anticoagulation therapy was initiated, and a Cardioverter Defibrillator was implanted. Another echo was performed focused on the LV function and visualisation of the coronary arteries. This confirmed the cardiac MRI findings, demonstrating two coronary artery aneurysms and a filling defect suggestive of thrombus in the more distal of the two aneurysms. Due to the lack of evidence of any other potential condition, a diagnosis of Kawasaki disease was made and anticoagulation therapy was continued. Conclusion Although Kawasaki disease (KD) has been investigated for over four decades, its cause is still unknown. Current understanding of the immune system response indicates response to a classic antigen, that in most patients is protective against future exposure (1). KD is an acute, self-limited vasculitis that affects young children. In a significant proportion of patients, it can originate coronary artery abnormalities, predominantly if the diagnosis is not achieved or treatment gets delayed. In the course of acute illness, the vascular architecture is destroyed by a necrotizing arteritis, causing hydrostatic pressure and leading to aneurysms in the affected areas (2). The imaging modality preferred for assessment of myocardial function and detection of coronary artery abnormalities is Echocardiography (2). In this case, given the unusual presentation of cardiac arrest and the diagnosis of KD we recommend a thorough assessment of the coronary arteries in echocardiography routinely. Abstract P728 Figure.