Patients with arrhythmogenic left ventricular cardiomyopathy who underwent heart transplantation: A case study

Arrhythmogenic left ventricular cardiomyopathy (ALVC) is a left ventricle (LV)-dominant arrhythmogenic cardiomyopathy subtype that presents with malignant ventricular tachycardia and LV dysfunction and can lead to sudden cardiac death (SCD). Three male patients—Case L (48 years old), Case N (41 years old), and Case Z (60 years old)—were admitted for heart transplantation because of advanced heart failure. Echocardiography revealed severely reduced LV systolic function (ejection fraction [EF] <30%) and LV dilatation (end-diastolic diameters ranged from 67 to 81 mm). Cardiac magnetic resonance showed extensive transmural late gadolinium enhancement in the LV without right ventricle involvement. Pathological staining of the explanted heart further confirmed extensive fibrofatty replacement in the LV. Autophagic activity, abnormal mitochondria, fragmented desmosomes, and disordered intercalated discs were identified on electron microscopy. Regarding the whole-exome sequencing results, BMP2 c.371C > T for Case L, MYH6 c.3413G > A and LDB3 c.1223A > G for Case N, and TNNC1 c.397A > T and FLNC c.2653G > A for Case Z were confirmed, which were all nondesmosomal variants. All patients were diagnosed with ALVC based on multimodal imaging, genetic analysis, and histopathological findings. All patients survived for 1 year after heart transplantation. The findings revealed by cardiac magnetic resonance, genetic testing, and histopathological staining provide a deeper understanding of the clinical features and outcomes of patients with advanced ALVC.