Abstract 4142194: Comparative Characteristics and Outcomes of Primary Compared to Glycogen Storage Disease-Associated Hypertrophic Cardiomyopathy

Background: Glycogen storage disease (GSD), characterized by defects in carbohydrate metabolism, may result in left ventricular hypertrophy (GSD-CM) that mimics primary hypertrophic cardiomyopathy (HCM). Differentiation of GSD-CM and HCM relies mostly on genetic testing. We aimed to evaluate differences in demographics, comorbidities and in-hospital outcomes of GSD-CM compared to HCM. Methods: National Inpatient Sample 2016-2021 was used to identify adults with GSD-CM and HCM using appropriate ICD codes. Logistic regression was applied to compare in-hospital outcomes. Results: From 2016-2021, 110 GSD-CM and 333,685 HCM adults were admitted. Most common admitting or principal diagnoses in the GSD-CM group were acute on chronic heart failure (23.8%) and pneumonia (14.3%). In comparison to HCM, GSD-CM cases were younger (44.3 -vs- 66 years), more likely to be males (66.7% -vs- 44.1%, p<0.001) and less likely to be caucasians (40.0% -vs- 67.6%, p<0.001). Most common causes of GSD were observed to be Pompe disease (50 cases) and von Gierke disease (25 cases). As shown in Table 1, despite GSD-CM cases having lower proportions of comorbidities including hypertension, diabetes mellitus, coronary artery disease, hyperlipidemia, and chronic kidney disease, GSD-CM had a longer length of stay (LOS) as compared to HCM (12.9 -vs- 5.9 days, p<0.001). GSD-CM also had a higher total hospital cost compared to HCM ($261,167 -vs- 87,246) and higher rates of in hospital complications such as mortality (4.8%-vs-3.5%, p=0.037), cardiogenic shock (9.5% -vs- 2.6%, p<0.001) and need for heart transplant (9.5% -vs- 0.2%, p=0.041). Conclusion: This retrospective database analysis comparing GSD-CM with HCM was indicative of higher prevalence amongst younger males and resulted in higher mortality, higher in-hospital complication rate, prolonged LOS, and increased total cost of hospitalization. While the overall proportion of GSD-CM compared to other cardiomyopathies remains low, this particular subset of patients warrants further study to better understand long-term outcomes.