Case#: Deceased child, female; age 5.5 months

DiseaseAssertion: Hypertrophic cardiomyopathy with endomyocardial fibroelastosis

FamilyInfo: The mother carried c.2373dup, and the father carried c.592G>T.

ParentalTesting: The mother carried c.2373dup, and the father carried c.592G>T.

CasePresentingHPOs: HP:0001706 HP:0200128 HP:0012664 HP:0002094 HP:0000961

CaseHPOFreeText: Acute heart failure; massive biventricular cardiac enlargement; biventricular dysfunction; progressive dyspnea; blue lips; pale appearance; endocardial fibrosis; cardiopulmonary arrest.

CaseNotHPOs: NR

CaseNotHPOFreeText: No congenital heart disease or valve abnormalities were found at autopsy

CasePreviousTesting: NR

Genotyping Method: Postmortem molecular testing

FunctionalAnalysis: NR

Variant: MYBPC3 c.592G>T (p.Asp198Tyr); missense

MYBPC3 c.2373dup, p.Trp792Valfs*41); frameshift duplication

ClinVar: c.592G>T: NR; c.2373dup: 42619

CAID: c.592G>T: NR; c.2373dup: CA012139

gnomAD: c.592G>T was not observed in more than 123,000 individuals; c.2373dup: 0.0017% overall

AdditionalInfo: The child died from severe early-onset cardiac disease at 5.5 months. Autopsy showed endomyocardial fibroelastosis and severe biventricular involvement.