Please, review article of Pediatric cardiomyopathies previous to next lessons.

• Primary Cardiomyopathies:  Disease of myocardium in which heart muscle is structurally and functionally abnormal in the absence of coronary disease or abnormal loading conditions (Valvar/CHD/Hypertension etc). Cardiomyopathies were defined as primary myocardial disorders of unknown cause; heart muscle disorders of known aetiology or associated with systemic disorders were classified as secondary or specific heart muscle diseases. Pediatric cardiomyopathies can result from coronary artery abnormalities, tachyarrhythmias, exposure to infection or toxins, or secondary to other underlying disorders.
• The incidence of primary CM in developed countries is reported to be between 0.8 and 1.3 cases per 100,000 children. Account for 60% of children requiring a cardiac transplant
• Because the accuracy and availability of genetic testing has increased, the importance of genetic mutations in the development of pediatric cardiomyopathies has become apparent. Pediatric cardiomyopathies are genetically heterogeneous with many different causative genes and multiple mutations in each gene. Variants in the same gene can cause different phenotypes.

Echocardiography establishes the cardiac phenotype and is performed serially during follow-up and helps to determine prognosis and changes in the treatment. In addition to clinically assessing for heart failure, evaluating the child with cardiomyopathy includes searching for an underlying metabolic, congenital, or acquired cause. This is particularly important in the infant population, where the incidence of metabolic disease is greater and includes potentially reversible conditions, such as primary carnitine deficiency.

Mutations in genes encoding components of the sarcomere or costamere and related binding proteins, Z-band, nuclear membrane, desmosome, mitochondrial, and calcium-handling proteins have all been found in children with cardiomyopathy. Pedigree and cardiac study in first degree relatives are recommended.