Inheritance of congenital heart disease

Congenital heart defects (CHD) are the most common developmental anomalies and are the leading noninfectious cause of mortality in newborn babies. It has been estimated that between four and ten live-born infants per 1000 have a cardiac malformation (0.4 to 1.0%), 40% of which are diagnosed in the first year of life. The European Registration of Congenital Anomalies (EUROCAT) reported a prevalence of 58.9/10,000 live births in the northern part of the Netherlands (0.6%). Hoffman estimated that the true prevalence of CHD may be as high as 53 per 1000 pregnancies (5.3%), including a 20% occurrence of heart defects in spontaneous abortion, a 10% occurrence in stillbirth, and a 1% occurrence in live birth.     

Ischemic heart disease as deficiency disease.

Four classes of agents capable of producing human illness have been identified: toxicity, heredity, infection and deficiency. The leading paradigm for the etiology and pathophysiology of ischemic heart disease in the 20th century was that of intoxication by too much of the wrong kind of dietary fat. This overemphasis on lipid metabolism persists because important data are neglected and because of inattention to details. For example, heart disease risk does not correlate with fat intake within nations in contrast to between nations. Also development of ischemic heart disease involves inter alia arterial spasm, cardiac rhythm, metabolism of connective tissue, glucose and homocysteine, plus paraoxonase activity and thrombus formation which generally are unaffected by dietary fat. Homocysteine thiolactone accumulates when homocysteine is high. This lactone specifically inhibits lysyl oxidase which depends on copper to catalyze cross linking of collagen and elastin in arteries and bone. The lactone is hydrolyzed by paraoxonase, activity of which can be decreased by copper deficiency. Just as cholesterol was an important focus for heart disease as intoxication, homocysteine can become an excellent focus for a paradigm shift to heart disease as deficiency because supplementation with several nutrients can alter homocysteine metabolism and decrease its plasma concentration. These supplements include betaine, copper, folate, pyridoxine and vitamin B-12. Opportunities for research on ischemic heart disease as deficiency disease are plentiful.