https://orcid.org/0009-0000-7425-8555
A 28-year-old woman was found to have Wolff–Parkinson–White syndrome on an electrocardiogram during a physical examination at a local hospital 7 years ago (Panel A). An echocardiogram revealed hypertrophy of the left ventricular wall. Initially, hypertrophic cardiomyopathy was suspected. For further diagnosis and treatment, she was admitted to our hospital 4 years ago. Advanced cardiac magnetic resonance (CMR) imaging showed hypertrophy in the left ventricle, with the interventricular septum reaching a maximum thickness of 21 mm at the end-diastolic phase (Panels B and C). Importantly, late gadolinium enhancement (LGE) imaging highlighted localized subendocardial to mid-wall enhancement in the apical–lateral wall, also involving the papillary and trabecular muscles (Panels D and E). This presentation led to the consideration of a hypertrophic cardiomyopathy phenotype mimicking another condition. Genetic testing revealed a mutation in the PRKAG2 gene (c.182G>A; PRKAG2:p.Arg61Gln), a mutation also carried by her mother. Myocardial biopsy showed hypertrophy of myocardial cells (Panel H), and electron microscopy identified a small number of glycogen particles, consistent with PRKAG2-related myocardial ultrastructural alterations (Panel I). She was referred for a CMR follow-up. Her recent CMR revealed an increase in LGE (Panel E). Native T1 mapping (Panel F) and extracellular volume (ECV) imaging (Panel G) indicated raised T1 and ECV values in the affected area. The case underscores the need for molecular screening for PRKAG2 gene mutations, particularly when cardiac MRI indicates atypical hypertrophic cardiomyopathy, in patients presenting with hypertrophy predominantly in the subendocardial and intermuscular enhancement. This is especially relevant in the coexistence of Wolff–Parkinson–White syndrome.
Funding
This study was funded by the Construction Research Project of Key Laboratory of Chinese Academy of Medical Sciences (grant 2019PT310025), the Youth Key Program of High-level Hospital Clinical Research (grant 2022-GSP-QZ-5) and Beijing Natural Science Foundation (7242110).
Data availability
The data underlying this article are available in the article.
Author notes
Conflict of interest: None declared.
