Cardiac Phenotype Characterization at MRI in Patients with Danon Disease: A Retrospective Multicenter Case Series.

Danon disease (DD) is a rare X-chromosome-linked dominant lysosomal glycogen storage disease. Its features have seldom been reported by using cardiac MRI. This case series aimed to evaluate cardiac features of DD on the basis of MRI observations from five centers in China. From January 2010 to May 2019, 16 patients with DD (13 male patients [81%]; median age, 19 years; age range, 14-44 years) underwent MRI. The most frequent DD cardiomyopathy manifestation was symmetric hypertrophy cardiomyopathy (HCM) phenotype (nine of 16; 56%), followed by asymmetric HCM phenotype (six of 16; 38%) and dilated cardiomyopathy phenotype (one of 16; 6%). The characteristic late gadolinium enhancement features included midbasal septum sparing (14 of 16; 88%) and apex involvement (16 of 16; 100%) with a base-to-apex increasing tendency, free wall involvement (15 of 16; 94%), and extensive subendocardium involvement (14 of 16; 88%). Abnormal T2 signal (seven of 16; 44%) and resting perfusion defect (14 of 16; 88%) were not uncommon in patients with DD. Furthermore, the cardiac MRI features of DD cohort in this study were compared with those of DD in previous literature and with genetically confirmed sarcomeric HCM.