- Congenital Heart Defects (CHD) are the most common type of birth defect. They include abnormalities in heart structure that occur before birth. These defects occur in the foetus while it is developing in the uterus during pregnancy. Chromosomal abnormalities can be a cause of CHD, although other causes include excessive alcohol consumption during pregnancy, the use of medications, maternal viral infections such as Rubella or measles during the first trimester, the presence of CHD in a parent or sibling and maternal illness (diabetes mellitus, phenylketonuria). The inheritance of these diseases follows an autosomal dominant pattern, although exceptions can be found. CHD encompasses a variety of defects that are commonly grouped based on the nature of the structural heart defect, resulting blood flow patterns, observed familial recurrence risks and shared susceptibility genes. According to the resulting blood pattern they can be classified as:
- Acyanotic conditions (“pink babies”): Have left-to-right shunt in which oxygenated blood from the lungs is shunted back into the pulmonary circulation. Examples of these include septal defects (Ventricular Septal Defect, Atrial Septal Defect), Patent Ductus Arteriosus, Coarctation of the Aorta etc.
- Cyanotic conditions (“blue babies”): Have right-to-left shunt in which deoxygenated blood is shunted into the systemic circulation. Examples of these include Transposition Of Great Vessels, Tetralogy Of Fallot, Truncus Arteriosus, Tricuspid Atresia, Total Anomalous Pulmonary Venous Return etc.
- The Igenomix Congenital Heart Disease Precision Panel can be used as a diagnostic and screening tool ultimately leading to a better management and prognosis of the disease. It provides a comprehensive analysis of the genes involved in this disease using next-generation sequencing (NGS) to fully understand the spectrum of relevant genes.
- The Igenomix Comprehensive Cardiology Precision Panel is indicated in those cases where there is a clinical suspicion or ultrasound finding with or without the following manifestations:
- Blue-tinted nails or lips
- Fast or troubled breathing (shortness of breath)
- Tiredness when feeding
- Sleepiness, tiredness and/or fatigue
- Ankle, leg or eye swelling
- Loss of consciousness during exertion
The clinical utility of this panel is:
- The genetic and molecular diagnosis for an accurate clinical diagnosis.
- Early initiation of treatment with a multidisciplinary team for appropriate surgical repair and interventional procedures to prevent further complications such as endocarditis, pulmonary hypertension, respiratory tract infections, arrhythmias, heart failure and sudden cardiac death.
- Appropriate prenatal diagnosis and close communication between obstetric, genetic and paediatric providers for optimization of neonatal outcomes.
- Risk assessment and genetic counselling of asymptomatic family members according to the mode of inheritance.
Baumgartner, H., & De Backer, J. (2020). The ESC Clinical Practice Guidelines for the Management of Adult Congenital Heart Disease 2020. European Heart Journal, 41(43), 4153-4154. doi: 10.1093/eurheartj/ehaa701
What are Congenital Heart Defects? | CDC. (2021). Retrieved 18 February 2021, from https://www.cdc.gov/ncbddd/heartdefects/facts.html
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