Endocardial fibroelastosis (EFE) is a rare heart disorder in which the endocardium of the heart becomes thickened by the proliferation of elastic and fibrous tissues. Signs and symptoms of the disease are characterized by impairment of cardiac function due to these multiple layers of collagen and elastin. It mainly affects infants and children with the usual age of presentation of one; however, it can sometimes be seen in adults. Several etiologies have been suggested for EFE, among which genetic etiology with inheritance of X-linked recessive and via a protein named Tafazzin is one of the most important ones. The clinical manifestations may vary and include constitutional, cardiovascular, fetus-related, gastrointestinal, and pulmonary signs and symptoms. The diagnostic approach is mostly similar to cardiac assessment, and the mainstay of management is heart failure control via pharmacologic agents.