Rare case of mitochondrial cardiomyopathy in adolescent girl

Abstract

Mitochondrial diseases are rare and heterogeneous conditions frequently affecting the heart. They are caused by mutations in nuclear or mitochondrial DNA with maternal inheritance or de novo occurrence. We present a case of 13-year-old girl with malignant mitochondrial cardiomyopathy. First presentation of the disease is with tamponade and atrial fibrillation. Cardiac imaging shows non-specific changes of the left ventricle that cannot be explained by any cardiomyopathy: hypertrophy, dilation, hypertrabeculation. These findings raised the suspicion for mitochondrial cardiomyopathy. The patient is examined by neurologist due to multisystem character of the disease. Electromyography reveals myopathy. Serum lactate and creatine phosphokinase are elevated. Acute inflammation is excluded with endomyocardial biopsy which also discovers complex III deficiency. Genetic testing identified likely pathogenic mutation in mitochondrial DNA with maternal inheritance. Two years after initial presentation patient was referred for cardiac transplantation due to fast progression of the disease. Mitochondrial cardiomyopathies have variable clinical manifestation which impedes the diagnosis and makes impossible the creation of unified criteria. The disease often affects various organs with high oxygen demand. Multiparametric approach and multidisciplinary team are recommended to increase diagnostic accuracy.

Keywords

• mitochondrial disease
• mitochondrial cardiomyopath