Eosinophilic Granulomatosis with Polyangiitis presenting as Non-ST-Elevation Myocardial Infarction: A Case Report

Background: Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare systemic necrotizing vasculitis of the small vessels. Organ manifestations are heterogenous, primary affecting the respiratory tract, but involvement of the peripheral nerves, gastrointestinal tract, skin and heart is also possible. EGPA typically progresses in three main phases: the prodromal phase with asthma and chronic rhinosinusitis as hallmark, the eosinophilic phase with organ-infiltration and the vasculitic phase. Notably, cardiac disease is one of the major predictors of adverse outcome in EGPA. In this case report, we present the history of a patient with suspected non-STelevation myocardial infarction (NSTEMI) treated at the University Heart and Vascular Center Hamburg.

Case report: In January 2023, a 49-year-old women was referred to our emergency room with suspicion of NETSMI. The patient reported left-sided chest pain irrespective of exertion as well as dizziness, nausea and reduced exercise capacity. The Electrocardiogram (ECG) revealed ST-segment depression in II, III, aVF, V5 and V6. Laboratory results included highly elevated N-terminal pro-B-type levels of 6667 pg/ml and a dynamic rise of troponine I from 4942 to 5146 ng/l. Emergency echocardiography showed normal cardiac function without wall motion abnormalities. A computed tomography (CT) scan of the thorax and abdomen revealed pneumonic infiltrates and a small subsegmental pulmonary embolism. ECG and biomarker findings as well as the clinic presentation led to the diagnosis of NSTEMI, prompting an invasive coronary angiography (ICA). Hereby, coronary artery disease, dissection or occlusion could be excluded. For further assessment and exclusion of myocarditis, cardiac magnetic resonance imaging (MRI) was conducted, which revealed global hypokinesia with mildly reduced ejection fraction. Furthermore, apical, subendothelial late-gadolinium enhancement was found, the pattern being reminiscent of vasculitis or an embolic event. After four days, the patient developed suddenly weakness of the left arm along with apraxia and confusion. Cranial CT scan excluded intracranial hemorrhage, the following cerebral MRI showed multiple bilateral cortical and subcortical micro-infarctions in the supratentorial medulla. As incidental finding, the sinus maxillaris exhibited signs of chronic sinusitis. Transoesophageal echocardiography and coagulation tests could not identify the etiology of the stroke. Finally, extensive laboratory assessment revealed eosinophilia of 36.8%. In an interdisciplinary approach (pneumology, rheumatology, cardiology), we decided to perform bronchoscopy for further assessment. Consequently, bronchial lavage showed chronic bronchitis without eosinophilia. Endobronchial biopsy of an enlarged lymph node eventually revealed multiple granulomas with an eosinophilic infiltrate (see figure 1), allowing the diagnosis of EGPA.

Conclusion and Discussion: Cardiac involvement is common in EGPA and is found in approximately 45% of cases, but the initial manifestation as NSTEMI in the eosinophilic phase is extremely rare. We only found one similar case with only cardiac symptoms at presentation and without coronary artery obstruction in ICA, however, cardiac MRI was not performed. All in all, diagnosis of EGPA is challenging due to the various manifestations. This is underlined by this case report and reminds clinicians to think broader and look for red flags like multiorgan involvement.