Acute Myocardial Dysfunction and Hypereosinophilic Infiltrative Myocarditis Secondary to New-Onset Pediatric Acute Lymphoblastic Leukemia.

Myocardial infiltration by eosinophils leads to myocardial inflammation and fibrosis, resulting in restrictive hemodynamics. We describe an uncommon presentation of eosinophilic predominant acute lymphoblastic leukemia that manifested with hypereosinophilic infiltrative myocarditis. (Level of Difficulty: Advanced.).