Aetiology                                                                                                

Congenital heart Disease is the commonest malformation and, after prematurity the commonest cause of neonatal and infant deaths in affluent societies. The overall incidence is 6-8 per 1000 live births. This figure includes small VSDs etc. The rate for significant disease defined as requiring intervention in the first year of life is half this figure (3-4/1000).

Chromosomal Disorders (Macro)

Trisomies (21, 18, 13) eg Down’s associated with septal defects including ASD, VSD, AVSD & PDA
Turners (XO) associated with bicuspid aortic valve & coarctation are common causes of congenital heart disease.

Chromosomal Microdeletions

These are are being identified at an ever increasing rate. Examples include chromosome 22 (conotruncal defects - interrupted aortic arch, tetralogy of Fallot, Truncus arteriosus), chromosome 12 (Noonan’s - PS, HCM), chromosome 7 (Williams – supravalve AS). FISH (fluorescent insitu hybridisation) techniques have allowed microdeletions of chromosomes to be identified at an ever increasing rate.

The current situation has recently been reviewed in an excellent series of eight articles by Azra Alizad MD and James B. Seward MD were published in Journal of the American Society of Echocardiography Jan to Aug 2000.

• Cardiomyopathy
• Fabry's Disease, Gaucher's Disease, Glycogen Storage Disease, Familial Hemochromatosis, Familial Hyperlipidemia
• Familial Atrial Septal Defect, Holt-Oram Syndrome, Osler-Weber-Rendu Disease, Scimitar Syndrome
• Ehlers-Danlos Syndrome, Marfan Syndrome, Morquio's Syndrome
• Neurofibromatosis, Pheochromocytoma, Syndrome Myxoma, Tuberous Sclerosis
• Down Syndrome, Shone's Syndrome, Turner's Syndrome, Williams Syndrome
• Alagille Syndrome, DiGeorge Syndrome and Velocardiofacial Syndrome, Goldenhar's Syndrome, Trisomy 13 (Patau's Syndrome), Trisomy 18 (Edwards' Syndrome)
• Syndromes of Asplenia and Polysplenia, Congenital Absence of the Pericardium, Kartagener's Syndrome, Polycystic Kidney Disease

Vitamin Supplementation

Studies by Botto et al have shown that periconceptual multivitamin use may significantly decrease the incidence of cardiac disease (Am J Epidemiol 2000 May 1;151(9):878-84). Conversely other studies by the same group showed a marked increase in transposition of great arteries in those mothers taking Vitamin A supplementation. (Epidemiology. 2001 Sep;12(5):482-4).

Micro-organisms

Congenital Rubella has for a long time been associated with an embryopathy which includes cardiac defects such as PDA, VSD/PS. Many viruses can cause a cardiomyopathy - Coxsackie is perhaps the commonest. CMV is also known to cause cardiac disease. Botto et al have shown there to be an association between maternal fever in pregnancy and the development of cardiac disease (Epidemiology 2002 Jul;13(4):485-8).

Drugs

Some drugs are known to cause cardiac disease - this list is by no means exhaustive.

• Lithium (Ebstein’s disease)
• Anticonvulsants
• Warfarin (VSD, PDA, ASD, ToF)
• Alcohol (PS, AS, CoA, VSD, ASD)

Maternal Disease

Maternal insulin dependent diabetes may cause structural disease and the incidence is related to the degree of glycaemic control i n the preconception period and the first trimester. In later pregnancy poor glycaemic control is associated with hypertrophic cardiomyopathy. Phenylketonuria is also associated with an increased incidence of structural cardiac disease.
Collagen disease eg SLE may cause complete heart block in fetal and early infant life.

Associations

Many malformations are associated with cardiac disease and this is not surprising as an insult during the period of organogenesis will affect many organs. Approximately 20% of children with congenital heart disease will have additional medical or learning problems. Tracheo-oesophageal fistula, duodenal atresia, omphalocele and renal disorders are particularly common.

This page was last edited 16/2/2004