Idiopathic Eosinophilic Myocarditis Presenting with Features of an Acute Coronary Syndrome

Abstract

Summary A 62-year-old female was admitted with severe left-sided chest pain, nausea and pre-syncope. She had widespread T wave inversion on ECG and elevated troponins and was suspected to have an acute coronary syndrome event. Invasive coronary angiogram revealed normal coronary anatomy with no flow-limiting lesions. Echocardiography and cardiac MRI revealed impaired left ventricular (LV) systolic impairment, a mobile LV apical thrombus and a moderate global pericardial effusion with no significant compromise. Full blood count analysis indicated the patient to have significant eosinophilia, and the patient was diagnosed with idiopathic eosinophilic myocarditis. She was commenced on Prednisolone and Apixaban, and eosinophil levels returned to normal after 10 days of steroids. Over the course of 3 months, the patient had a complete recovery of her LV function and resolution of the LV thrombus. This case highlights a rare, reversible case of idiopathic eosinophilic myocarditis which may present similar to acute coronary syndrome. Learning points: Eosinophilic myocarditis (EM) is a rare disease that can exhibit symptoms similar to acute coronary syndrome events. The diagnosis of EM should be considered in patients with chest pain, normal coronary angiogram and pronounced eosinophilia levels. Endomyocardial biopsy is the gold standard diagnostic tool; however, it has a low sensitivity detection rate and its use is not indicated in some patients. Echocardiography is useful in the initial detection of cardiac involvement and complications. However, echocardiography lacks diagnostic specificity for all forms of myocarditis including EM. Cardiac magnetic resonance is a useful method and may add in diagnosing all forms of myocarditis including EM. Patients with EM should be identified promptly and treated with high doses of oral glucocorticoid to reduce the risk of permanent cardiac dysfunction.

Case Report: Multimodal Imaging Guides the Management of an Eosinophilic Leukemia Patient With Eosinophilic Myocarditis and Intracardiac Thrombus

“…Therefore, in our case with chest pain, pronounced eosinophilia levels, and normal coronary computed tomography angiography, the diagnosis of EM should be considered. In some individuals, EM masquerades as acute coronary syndrome, with severe chest pain, electrocardiographic changes, and elevated serum levels of troponins (12). If patients who have hypereosinophilia presenting as acute coronary syndrome only receive stent implantation and anti-angina pectoris, coronary spasm will occur repeatedly and may even lead to sudden death.…”

Cardiogenic Shock Induced by Anterior Pituitary Hypofunction and Thyrotoxicosis

“…In 2019, Mosebach et al reported a case of acute myocarditis presenting as an acute coronary syndrome [7]. In 2020, Tran et al studied a case of idiopathic eosinophilic myocarditis presenting with features of an acute coronary syndrome [8]. Viral myocarditis is regarded as a precursor of cardiomyopathy, which results from common viral infections and post-viral immune-mediated responses [9].…”

Eosinophilic Myocarditis: An Often-Overlooked Diagnosis in Patients Presenting with Heart Failure

“…The extent of fibrosis shows thickening of involved valve leaflets, and an increase in the intensity of endomyocardial echoes in areas of endomyocardial fibrosis. However, the accuracy of TTE to diagnosis is limited due to highly variable finding associated with myocarditis resulting false negative diagnosis [10]. Coronary angiography does not diagnose the EM, but it helps to rule out acute coronary disease.…”