Pediatric Cardiology

Biography

Biography: Krzysztof Piotrowski

Abstract

Congenital Heart Diseases (CHD) are the most common malformations both as an isolated form and a part of genetic syndromes. Extraordinarily fast development of molecular genetics confirms that almost all CHD are genetically dependent in terms of micro-aberrations in different regions of a chromosome or single gene mutations. On the other hand, CHD are an important component of diverse genetic diseases, including monogenic, metabolic and mitochondrial disorders, most often as secondary cardiomyopathies. The genes participating there-in are located nearly on each chromosome, mainly on pathways, along with ligand genes and co-factors, transcription factors or individually. Many mechanisms on heart development are based on the balance between apoptosis, proliferation and migration. Crucial genes controlling fetal development, including the creation of heart tube and the forming of left and right ventricular outflow are primary ‘homeobox’ genes grouped in 4 clusters HOX1-4. Other genes condition the forming of different structures. Moreover, in numerous functional disorders, for example the arrhythmia or block, the reason is also genetic, namely the mutation of ion- channel gene placed in 6 chromosomes. Many genes of cardio-genesis were identified, for example PTPN11 gene in Noonan syndrome. The gene is also responsible for the development of pulmonary valves or TBX5 gene in Holt-Oram Syndrome. Heart development is also affected by the imprinting (about 30 genes) and the inactivation of the X chromosome in day 21 stage of embryo. We propose, e.g. a practical classification could refer to specific CHD characteristic of particular disorders, which might prove helpful in daily practice because in prenatal diagnosis CHD is often the sole syndrome confirmed by USG scan, which may depend on truly isolated nature or non-specific mild ultrasound co-markers.