Endocardial fibroelastosis causing sudden death in an infant: Autopsy case report of an unusual lesion

Area of Science:

• Cardiovascular Pathology
• Pediatric Cardiology

Background:

• Endocardial fibroelastosis (EFE) involves abnormal proliferation of elastic and collagenous fibers in the heart's endocardium.
• This condition can lead to diffuse or localized endocardial thickening, impacting cardiac function.

Observation:

• A case study of a 4.5-month-old infant presenting with seizures and subsequent heart failure.
• The infant died within a week of hospital admission.
• Postmortem examination revealed an enlarged heart with dilated ventricles and markedly thickened, whitish endocardium of the left ventricle.

Findings:

• Histopathology confirmed a thick layer of collagenous fibrous tissue in the endocardium.
• Masson trichrome staining supported the diagnosis of endocardial fibroelastosis.
• The cause of death was attributed to dilated cardiomyopathy secondary to endocardial fibroelastosis.

Implications:

• This case underscores the importance of gross specimen examination and special stains in postmortem diagnostics.
• Understanding the underlying mechanisms of myocardial fibrosis, potentially involving genetic, infectious, inflammatory, or nutritional factors, requires further investigation.
• Accurate diagnosis of rare pediatric cardiac conditions is crucial for understanding disease progression and potential interventions.