CHDFNigeria
Definition
Cyanotic CHD is a group of congenital heart defects that results in low levels of oxygen in the blood, leading to cyanosis (a bluish discoloration of the skin, lips, and nails). Cyanosis occurs because of a right-to-left shunt, where oxygen-poor blood bypasses the lungs and mixes with oxygenated blood. In cyanotic CHD, there is a structural abnormality that causes deoxygenated blood to flow from the right side of the heart directly to the left side, entering systemic circulation without passing through the lungs for oxygenation. This mixing of blood reduces the overall oxygen saturation, leading to visible cyanosis.
Risk factors
As with many other CHDs, the risk factors included are linked to maternal, or paternal conditions/exposures as well as their genes. They include:
- Maternal infection: having German measles (rubella) or another viral illness during early pregnancy.
- Family history of congenital heart disease.
- Drinking alcohol during pregnancy.
- Smoking before or during pregnancy.
- Poorly controlled diabetes during pregnancy.
- Use of certain medications during pregnancy, including some used to treat acne, bipolar disorder and seizures.
Diagnosis and Diagnostic Investigations
Prenatal diagnosis: This is usually carried out in the prenatal period when the child is still in utero as part of anomaly screening for pregnant women around 20 weeks gestational age. A foetal echocardiography helps identify and detect CHDs at this stage.
Postnatal diagnosis (after childbirth): These are carried out at any stage after the child is born, they include:
- Physical examination: here the child is examined physically from head to toe by a clinician (specialist nurses, midwife, medical officer, specialist doctors or consultants) for features of CHD and other congenital diseases which might necessitate further diagnosis and help rule out congenital syndromes like VACTERL
- Auscultation: The clinician/paediatrician will also listen to the chest for murmur.
- Pulse oximetry: Which is a simple bed side test where a pulse oximeter is connected to a finger or toes to take the oxygen level reading. Oxygen saturation levels, SPO2 are usually less than 90%. This can be monitored continuously or one-off at your appointment.
- Chest X-ray: This is a radiological examination that looks into the chest organ. This service is usually available in most general, private, and tertiary hospitals in Nigeria.
- Electrocardiogram (ECG): This is a non-invasive test to check the electrical activity of the heart at the point of care. It can give clues about heart enlargement and heart muscle functions. ECG is readily available in diagnostic centres and teaching hospitals.
- Echocardiography: This uses soundwaves to visualize the heart. The cardiologist or sonographer take images, pictures, flow, pressure or volume across the heart chambers. This can be done either by Transoesophageal (TOE the oral cavity) means or transthoracic echocardiography, TTE means. TOE is invasive requiring admission, sedation or some anaesthesia. TTE is available and common in Nigeria, especially in teaching hospitals like LUTH, FMC, UPTH, diagnostic centres like Afri-global, as well as top private hospitals in Nigeria.
- Cardiac catheterization (diagnostic): Done by trained cardiologist helps to further examine the heart in order to arrive at definitive conclusions. Diagnostic cath help PVR studies and vascular measurements possible. Paediatric cardiac catheterization service is available in less than or about 5 centres in Nigeria as of 2025.
- Computed Tomography or Cardiac CT scan: uses X-ray and computer to take cross-sectional images of the heart. It gives detailed view of internal organs, bones and soft tissue in the mediastinum.
Common Types of Cyanotic CHD:
1. Tetralogy of Fallot (TOF): Characterized by four heart defects—ventricular septal defect (VSD), pulmonary stenosis, right ventricular hypertrophy, and an overriding aorta—resulting in oxygen-poor blood reaching systemic circulation.
2. Transposition of the Great Arteries (TGA): The positions of the aorta and pulmonary artery are swapped, causing oxygen-poor blood to be circulated to the body, while oxygen-rich blood circulates back to the lungs.
3. Truncus Arteriosus: A single blood vessel comes out of the heart instead of separate pulmonary artery and aorta, causing mixed oxygenated and deoxygenated blood to be distributed throughout the body.
4. Total Anomalous Pulmonary Venous Return (TAPVR): Pulmonary veins drain into the right side of the heart instead of the left, leading to mixed blood entering systemic circulation.
5. Tricuspid Atresia: Here the right side of the heart is underdeveloped.
Clinical presentation: CCHDs presentation depends on the lesion type, however the following signs and symptoms are commonly seen.
- Cyanosis
- Clubbing
- Acidosis
- Increased respiratory rate
- Parlor
- Increased heart rate
- Lethargy
- Cyanotic spells
- Poor response to oxygenation
- Heart murmur
- Finger/digital clubbing
Complications
CCHDs can lead to development of spell episodes, desaturations, fainting, and sudden cardiac arrest. Post operative complication following cardiac surgery can include prolonged hospitalization, cardiac arrest, arrythmias (JET), infection, surgical wound infection, even death in the operating room or during the period of treatment.
Generally, CCHDs are associated with higher mortality (death) rate with many occurring in the neonatal and infant age.
Management of Cyanotic Congenital Heart Defects.
Most CCHDs are corrected surgically, although stabilization of child is necessary. The Nigerian Open-Heart Surgery Registry can provide insight on which hospital does which and their figures. https://www.nigeriaheartregistry.com/operation-activity-by-institutions
Nutritional support is mostly essential for children with CHDs because some of these children become tired while feeding or expend calories at a higher than normal rate. To make sure babies have a healthy weight gain, a special high-calorie formula might be prescribed. Some babies become extremely tired while feeding by themselves, hence, they might need to be fed through a feeding tube enterally (usually NG tube passed in the nose). Cardiac Nutritionist may be very helpful; however, this service is nearly unavailable in Nigeria.
Other specialist services like Speech and language therapist, Physiotherapist, Respiratory therapist, Dietitians, Pharmacist , Psychotherapist, play specialist etc, all play huge roles in the successful management of children with congenital heart defects, and their families especially post-operatively.
What to Expect After Treatment
- Recovery: With early surgery, many children live into adulthood (61–85% survival at 20 years post-Fontan). Multiple surgeries are needed, and exercise capacity may be limited.
- Follow-Up: Lifelong care with a pediatric or adult congenital heart specialist is essential. Regular echocardiograms, ECGs, and check-ups monitor heart function.
- Complications: Risks include arrhythmias, stroke (if shunts remain), heart failure, or need for heart transplantation. Preventive measures for bacterial endocarditis are required for lifelong.
- Support: Join support groups (e.g., American Heart Association, Mended Little Hearts) for emotional and practical support.
With treatment, many children with Cyanotic CHD can thrive.
How to Help Your Child
- Act Quickly: Seek immediate medical help if you notice cyanosis, fast breathing, or poor feeding.
- Follow Medical Advice: Attend all appointments and follow medication or surgery plans.
- Keep Records: Document your child’s diagnosis, surgeries, medications, and doctor contacts for easy reference.
- Stay Informed: Ask your cardiologist about the Cyanotic CHD, treatment plans, and long-term care.
- Seek Support: Connect with other families through support groups or organizations like the National Organization for Rare Disorders (NORD) and Congenital Heart Disease Foundation of Nigeria (CHDFNigeria). Follow CHDFNigeria on all platforms for up-to-date information about your child’s condition.
