Retrospective Evaluation of Patients Diagnosed with Pediatric Metabolic Cardiomyopathy

Objective: In this study, we aimed to investigate the prognosis of cardiomyopathies due to inherited metabolic diseases and the effects of current treatments on survival and cardiomyopathy by analyzing the cardiac data of the patients who were followed up with the diagnosis of inherited metabolic disease and diagnosed with cardiomyopathy in the Department of Pediatric Metabolism and Nutrition at Çukurova University Medical Faculty. Material and Method: A total of 102 patients aged 0-18 years who were diagnosed with cardiomyopathy due to an inherited metabolic disease between 2010 and 2020 in the Department of Pediatric Metabolism and Nutrition were included in the study. Patients' symptoms at admission, diagnosis of inherited metabolic disease, type of cardiomyopathy, and whether they received specific treatment for inherited metabolic disease were evaluated retrospectively. In addition, echocardiographic data of 95 patients who came to the control visits at the first admission and follow-up were compared. Factors affecting morbidity and mortality were investigated. Results: The mean follow-up period of 95 patients was 60.9±54.6 months. Sixty patients (58.8%) had glycogen storage disease, 17 (16.7%) lysosomal storage disease, 11 (10.8%) fatty acid oxidation disorder, 11 (10.8%) mitochondrial disease, and 3 patients (2.9%) was diagnosed with aminoacid and organic acid metabolism disorder. The most common inherited metabolic disease subgroup was Pompe disease (n=47; 46%). The most common complaints at presentation to the cardiology outpatient clinic were respiratory distress (n=57; 55.9%), feeding difficulties (n=22; 21.6%) and cyanosis (n=20; 19.6%). The mean age at which patients were diagnosed with cardiomyopathy was 26.2±28.2 months. During the follow-up, arrhythmia was detected in 20 patients (19.6%). The most common arrhythmia was supraventricular tachycardia (n=8; 7.8%). Hypertrophic cardiomyopathy was present in 85.3% (n=87), dilated cardiomyopathy in 10.8% (n=11) and left ventricular noncompaction cardiomyopathy in 3.9% (n=4) of the patients. During follow-up, cardiomyopathy improved in 44 (46.3%) patients. Respiratory distress was detected in 40% (n=38) of the treated patients, and the survival rate was 60% (n=57). Twenty-two of the patients who died, 22 (58%) had glycogen storage disease, 8 (21%) had lysosomal storage disease, 5 (13%) had mitochondrial disease, 2 (5%) had fatty acid oxidation disorder, and had (3%) were aminoacid and organic acid metabolism disorders. Cardiomyopathy patients with a diagnosis of lysosomal storage disease were the group with the highest risk of death (p=0.021). It was determined that the interventricular septum Z score, left ventricular posterior wall diameter Z score and left ventricular mass index decreased significantly with enzyme replacement therapy in Pompe patients (p=0,001), and the shortening fraction and ejection fraction values of the patients diagnosed with fatty acid oxidation disorder increased significantly in the post-treatment period (p=0.011 and p=0.018, respectively). No significant change was observed in the echocardiographic data obtained before and after treatment in patients followed up with the diagnosis of other inherited metabolic diseases. Conclusion: Cardiac problems observed in children with inborn errors of metabolism have been increasingly defined. Cardiac involvement leads to a significant increase in morbidity and mortality. Although cardiomyopathy and echocardiographic findings can be improved, especially in Pompe patients, with inherited metabolic diseasespecific enzyme therapy, mortality is still high in inherited errors of metabolism. Key Words: Echocardiography, Cardiomyopathy, Inherited Metabolic Disease