The role of echocadiography in the differential diagnosis between PRKAG2 syndrome and Fabry disease

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background Storage of glycogen and glycosphingolipids occurs in the heart with PRKAG2 Syndrome and Fabry Disease (FD), respectively. Identification of specific echocardiographic parameters could contribute to early diagnosis, which is fundamental to initiate appropriate treatment and improve prognosis. Material and methods: Prospective, transversal, observational study involving 45 patients, 30 genetically identified with the PRKAG2 gene mutation and 15 with FD. Conventional transthoracic, bi-, and tridimensional echocardiography as well as strain/strain rate speckle tracking were measured during one examination. Specific echocardiographic measurements were obtained and the data exported to a workstation for subsequent evaluation. Analyses were performed with 5% significance using the R program, version 3.1.3. Results: Compared to FD patients, PRKAG2 patients presented increased left atrium volume index, mean LV septum, posterior wall thickness, right ventricle (RV) dimensional values, and RV thickness in diastole. LV hypertrophy was found in varying degrees in 25 (86%) of PRKAG2 and 8 (53%) of FD Pts. We detected a binary appearance of LV endocardial border ("binary sign") and hypertrophy of the anterolateral papilary muscle in 60% of FD Pts. PRKAG2 Pts showed reduced global longitudinal strain (2DGLS), 4D GLS, 4D global radial strain (GRS), and aortic diameter compared to FD patients. In PRKAG2 Pts the bull’s-eye plot showed a stripe-like pattern. In FD Pts, however, it showed a peak systolic strain reduction in basal and mid- anterolateral segments. Conclusion: Echocardiography is an important technique in differentiating both diseases to determine adequate treatment and prognosis. We have demonstrated that PRKAG2 Pts present moderately greater cardiac involvement than FD Pts.