Congenital Heart  Disease is defined as an abnormality in cardio circulatory structure  or function that is present at birth even if discovered much later. Congenital cardiovascular malformations usually result from altered embryonic development of a normal structure or failure of such a structure to progress beyond an early stage of embryonic or fetal development. In united states 40,000 babies are born each year with congenital heart defects. Approximately 0.8% of live births are complicated by a cardiovascular malformation. The congenital disease may be simple, moderately complex and very complex. Moderately and very complex patients should be monitored throughout their lives in a specialized centre.

      Some known causes of CHD are  Diabetes, Rubella, Influenza, maternal phenylketonuria , Obesity Seizure disorder and medications, HIV, Retinoic acid , Thalidomide , Sulfa drugs,  Alcohol and Smoking .

Maternal Diabetes : Relative risk for cardiac defect is estimated to be 4 to 5 times.  Preexisting and gestational diabetes can lead to conotruncal anomalies, outflow tract defects, d TGA, Situs inversus Situs ambiguous. Hypertrophic cardiomyopathy is usually non obstructive.  Strict glycemic control before conception and during the course of pregnancy has been shown to reduce diabetic embryopathy significantly. 

Congenital Rubella Syndrome : Most common cardiac associations of congenital rubella syndrome are pulmonic stenosis and PDA. Risk of rubella embryopathy can be virtually eliminated by ensuring that women of child bearing age are immunization against rubella. However irrespective of immunization status every pregnant woman should be advised to maintain good hygiene and to avoid contact with possible viral infections if possible. 

Maternal phenylketonuria : Maternal phenylketonuria is associated with left obstructive lesions, Septal defects and TOF. Relative risk is 6 to 15 fold high. If the biochemical control is poor, pregnancy can be hazardous and counseling can be attempted on this issue. Rigid diet control and maintenance of near normal levels before conception and during the course of pregnancy , the additional risk involved can be nullified.

Obesity : Obesity has at least 2 fold to 6.5 fold risk of cardiac defects as compared with non obese. Achieving a healthy lifestyle with disciplined diet and exercise in tandem with appropriate medical advice will help ensuring health of offspring.

Epilepsy and antiepileptic medication :  Epilepsy itself associated with congenital heart defects , simultaneously antiepileptic drugs has teratogenc  effect . Fetal hydantoin syndrome, VSD, ASD and PDA are associated with it. Optimal medication and good control of seizure activity is cornerstone of prevention. 

HIV  Infection : HIV has increased risk of dilated cardiomyopathy and disproportionate LV hypertrophy. It is prudent to advice every pregnant woman to take proper care of overall wellbeing and to strictly adhere to the standards of care and medication with correct execution of peripartum protocols of management.  

Drugs : Drugs that have teratogenic effect and cause congenital  heart disease that are to be avoided are Retinoic acid and Vit A congeners, maternal vaginal metronidazole, high dose fluconazole, zidovudine, thalidomide, lithium, maternal alcohol ingestion, maternal cocaine and marijuana ingestion and  maternal tobacco ingestion. 

Social and epidemiological issues : Elderly primi has risk of TGA, Ebstein anomaly, bicuspid aortic valve and ASD. Young maternal age < 20 are associated with increased risk of tricuspid atresia.

Prevention of Congenital heart disease

CHD  has a large scope for prevention. The broad categorization ofprevention can be summarized as

1. 1. Primary prevention : modification / abolishment of risk factors eg. vaccines or health promotion via         exercise, vitamins.
2. 2. Secondary prevention : Recognisation of sub clinical disease and early treatment of initial clinical manifestations to prevent progression of disease.
3. 3. Tertiary prevention : limiting the disability to the least possible and aiding the recovery from complications eg rehabilitation efforts. 

To conclude any women of child bearing age and a prospective mother should follow the following agenda.

1. 1. Folic acid 400mcg for 3 months
2. 2. Screening and management of phenylketonuria and DM
3. 3. Immunization  rubella
4. 4. Consult physician before taking any medicine during pregnancy
5. 5. Avoid contact with people with flu or any febrile illness
6. 6. If in doubt get a fetal echocardiogram at 16 to 18 weeks of gestation.

Dr Manjulata Mahanta, MD Pediatrics

HEARTMATE INSTITUTE.

B-1514, Sector 6. CDA. Cuttack.

9040183301, 9040283301