Eosinophilic myocarditis mimicking acute coronary syndrome secondary to idiopathic hypereosinophilic syndrome: a case report

Reza Amini,Craig Nielsen

doi:10.1186/1752-1947-4-40

Abstract

IntroductionEosinophilic myocarditis is a rare form of myocarditis. It is characterized pathologically by diffuse or focal myocardial inflammation with eosinophilic infiltration, often in association with peripheral blood eosinophilia. We report a case of eosinophilic myocarditis secondary to hypereosinophilic syndrome.Case presentationA 74-year-old Caucasian woman with a history of asthma, paroxysmal atrial fibrillation, stroke and coronary artery disease presented to the emergency department of our hospital with chest pain. Evaluations revealed that she had peripheral blood eosinophilia and elevated cardiac enzymes. Electrocardiographic findings were nonspecific. Her electrocardiographic finding and elevated cardiac enzymes pointed to a non-ST-elevated myocardial infarction. Echocardiogram showed a severe decrease in the left ventricular systolic function. Coronary angiogram showed nonobstructive coronary artery disease. She then underwent cardiac magnetic resonance imaging, which showed neither infiltrative myocardial diseases nor any evidence of infarction. This was followed by an endomyocardial biopsy which was consistent with eosinophilic myocarditis. Hematologic workup regarding her eosinophilia was consistent with hypereosinophilic syndrome. After being started on steroid therapy, her peripheral eosinophilia resolved and her symptoms improved. Her left ventricular ejection fraction, however, did not improve.ConclusionEosinophilic myocarditis can present like an acute myocardial infarction and should be considered in the differential diagnosis of acute coronary syndrome in patients with a history of allergy, asthma or acute reduction of the left ventricular function with or without peripheral eosinophilia.

Highlights

Eosinophilic myocarditis is a rare form of myocarditis
Eosinophilic myocarditis can present like an acute myocardial infarction and should be considered in the differential diagnosis of acute coronary syndrome in patients with a history of allergy, asthma or acute reduction of the left ventricular function with or without peripheral eosinophilia
Well-established etiologies include hypersensitivity myocarditis due to medication (Table 1); acute necrotizing eosinophilic myocarditis (ANEM), usually with a fulminant course; hypersensitivity myocarditis associated with specific agents including smallpox, meningococcal C and hepatitis B vaccines; hypereosinophilic syndrome; Loeffler’s endocarditis; tropical endomyocardial fibrosis; vasculitis such as Churg-Strauss; and malignancies including Tcell lymphoma and cancer of the lung and biliary tract [8,15]

Summary

Conclusion

Our patient with EM secondary to idiopathic hypereosinophilic syndrome presented with several misleading features, including symptoms of acute coronary syndrome, nonspecific electrocardiography changes, echocardiographic findings and increased cardiac enzymes. Negative workup with regard to coronary artery disease prompted us to look for infiltrative disease with cardiac magnetic resonance imaging and endomyocardial biopsy. The endomyocardial biopsy results led to the correct diagnosis and guided the patient’s treatment. In patients with a history of allergy and asthma and presenting with chest pain or symptoms of heart failure, EM should be considered. Because of the disease’s potentially fatal course if left untreated, endomyocardial biopsy should be performed and repeated if necessary. Consent Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal

Introduction

Discussion

Findings

Löffler W