case_images: PMC11007043_01
case_images: Electrocardiographic findings in Danon disease. (A) Electrocardiogram at pre-excitation in 2003. (B) Electrocardiogram at atrial flutter in 2016. (C) Electrocardiogram at ventricular tachycardia in 2016. (D) Electrocardiogram at sinus rhythm with ventricular premature beats and a complete left bundle branch block in 2019.
case_images: fcvm-11-1369680-g001.jpg
case_images: PMC11007043_01_fcvm-11-1369680-g001.jpg
case_images: F1
case_images: In her 30s, she was diagnosed with Wolff-Parkinson-White (WPW) syndrome (Figure 1A) with paroxysmal supraventricular tachycardia, for which she received her first radiofrequency catheter ablation (RFCA). Three years ago, she was admitted with paroxysmal atrial flutter (Figure 1B), during which echocardiography revealed an enlargement of the left atrium (45 mm) but normal left ventricular wall thickness (10 mm), chamber size (51 mm), and ejection fraction (EF) (72%). Upon admission, ventricular tachycardia (Figure 1C) was recorded, which was electrically converted to sinus rhythm with a complete left bundle branch block (Figure 1D).
case_images: Imaging and genetic findings in Danon disease. (A) Patient's echocardiography view. (B,C) Patient's late gadolinium enhancement by CMR (yellow arrow). (D) Genetic analysis of the clinically affected member.
case_images: fcvm-11-1369680-g002.jpg
case_images: PMC11007043_01_fcvm-11-1369680-g002.jpg
case_images: F2
case_images: The LA remained enlarged, but the wall thickness was normal (Figure 2A). Cardiovascular magnetic resonance (CMR) imaging was further performed, which displayed endomyocardial late gadolinium enhancement (LGE) in the anterior, inferior, and lateral walls (Figures 2B,C). The following whole-exome sequencing (WES) demonstrated a heterozygous variant in lysosome-associated membrane protein 2 (LAMP2) gene (c.696T>A; p.Cys232Ter) (Figure 2D), which is located in coding exon 5 of LAMP2.