Loeffler Endocarditis, also known as primary eosinophilic endomyocardial restrictive cardiomyopathy, is related to primary hypereosinophilic syndrome and myeloid and lymphoid neoplasms associated with pdgfra rearrangement. An important gene associated with Loeffler Endocarditis is FIP1L1 (Factor Interacting With PAPOLA And CPSF1), and among its related pathways/superpathways are Innate Immune System and Overview of interferons-mediated signaling pathway. Affiliated tissues include heart and thyroid, and related phenotypes are eosinophilia and restrictive cardiomyopathy