JACC Case Rep. 2026 Jul 29;31(30):108232. doi: 10.1016/j.jaccas.2026.108232.
ABSTRACT
BACKGROUND: PRKAG2 cardiomyopathy is a genetic cardiomyopathy that phenotypically resembles hypertrophic cardiomyopathy (HCM) and results from myocardial glycogen accumulation. In addition to left ventricular hypertrophy (LVH), PRKAG2 cardiomyopathy is associated with ventricular pre-excitation, cardiac conduction disease, and ventricular tachyarrhythmias.
CASE SUMMARY: A 34-year-old woman with a family history of HCM and Wolff-Parkinson-White syndrome presented with exertional dyspnea, chest discomfort, and near-syncope. Electrocardiogram revealed LVH, T-wave inversions, and pre-excitation. Echocardiography demonstrated severe LVH with outflow tract obstruction. Based on family history, LVH, and pre-excitation, PRKAG2 syndrome was suspected and later confirmed by genetic testing.
DISCUSSION: PRKAG2 cardiomyopathy results from glycogen accumulation rather than sarcomeric hypertrophy. This case highlights the diagnostic importance of electrocardiography-detected pre-excitation in a patient with severe LVH, raising suspicion for nonsarcomeric HCM.
TAKE-HOME MESSAGES: Consider PRKAG2 mutations in HCM patients with pre-excitation or conduction disease. Early genetic diagnosis guides management and informs family screening.
PMID:42530173 | PMC:PMC13420607 | DOI:10.1016/j.jaccas.2026.108232