Cyanotic heart diseases are congenital heart defects (heart diseases present at birth) that result in low oxygen levels in the blood and cause the child's skin to look blue (cyanosis). This bluish coloration is most often detected on the lips, fingers, and toes or during exercise. Some heart defects cause major problems immediately after birth, and some cause few if any problems until adulthood. Not all congenital heart diseases are cyanotic. Congenital heart defects that cause cyanosis include the following: Most congenital heart disease occurs as a birth defect limited only to the heart, but some conditions occur as part of genetic and chromosomal syndromes that affect many organs. Some syndromes that include congenital heart disease (not all cyanotic) are Down syndrome, trisomy 13, Turner's syndrome, Marfan syndrome, Noonan syndrome, and Ellis-van Creveld syndrome.
Some congenital heart diseases are caused by drugs, chemical exposure, or infections during pregnancy. Fetal rubella, infection by cytomegallovirus (CMV), maternal alcohol use (fetal alcohol syndrome), lithium carbonate use (for manic-depressive disorder), and retinoic acid use (for acne) are examples of infections and drugs that can cause congenital heart disease.
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