Complete Atrioventricular Septal Defect with Atrial and Ventricular Components

Complete atrioventricular septal defect with atrial and ventricular components (complete AVSD) is a birth heart problem where there is one large hole in the center of the heart and one shared valve instead of two separate valves. Blood can pass freely between the top chambers and the bottom chambers, and between the right and left sides, so oxygen-rich and oxygen-poor blood mix. In a normal heart, a solid wall separates the two upper chambers (atria) and the two lower chambers (ventricles), and there are two separate valves (mitral and tricuspid) that control blood flow between them. In complete AVSD, the wall is missing in the middle, and the valves are fused into one “common” valve, so the heart has to work much harder than normal.

Complete atrioventricular septal defect (AVSD) with atrial and ventricular components means there is a big hole in the middle of the heart, where the wall between the top chambers (atria) and the wall between the bottom chambers (ventricles) should meet. There is also one large “common” valve instead of two separate valves (mitral and tricuspid).

Because of this hole and the abnormal valve, oxygen-rich blood and oxygen-poor blood mix together. Blood flows in the wrong direction and in the wrong amounts to the lungs and to the body. The heart has to work very hard, and this can quickly lead to heart failure, high blood pressure in the lungs (pulmonary hypertension), poor feeding, and poor weight gain in babies.

For a complete AVSD, surgery is the main and only curative treatment. Medicines, nutrition, and other therapies are “supportive” care. They help the baby stay stable and grow enough to have safe surgery and then help protect the heart and lungs after surgery. Most guidelines recommend repair in early infancy, usually by 2–6 months of age, before permanent lung damage develops.

This defect is congenital, which means it starts when the baby is still in the womb. It does not close by itself and almost always needs surgery in early childhood to close the holes and repair the valve so blood flows in the correct one-way path.

Other names

Doctors use several other names for this same defect. Common names include atrioventricular canal defect (AV canal), atrioventricular septal defect (AVSD), endocardial cushion defect, complete AV canal defect (CAVC), and common atrioventricular canal. All of these describe a similar problem in the central part of the heart where the walls and valves should meet.

Basic anatomy and what happens in complete AVSD

In a healthy heart, the right side pumps blood to the lungs to pick up oxygen, and the left side pumps oxygen-rich blood to the body. A firm wall keeps the two sides separate so the two blood streams do not mix. Two valves (mitral on the left, tricuspid on the right) keep blood moving in one direction from the atria into the ventricles.

In complete AVSD with atrial and ventricular components, there is a large combined hole in the lower part of the atrial wall (ASD) and the upper part of the ventricular wall (VSD), plus one shared atrioventricular valve. Because of this, oxygen-rich blood from the left heart mixes with oxygen-poor blood in the right heart, and some blood leaks backward through the faulty valve. This causes high blood flow and pressure in the lungs and can quickly lead to heart failure and lung damage if not treated.

Types of complete atrioventricular septal defect

Even though we are talking about complete AVSD, doctors still divide it into types based on how the common valve sits and how blood flows to the two ventricles.

1. Balanced complete AVSD
   In this type, the common valve sends blood fairly evenly to both ventricles. Both the right and left ventricles are normal size. This makes surgery easier and the long-term outlook better, because both pumping chambers can work well after repair.

2. Unbalanced complete AVSD – right-dominant
   Here, most of the blood from the common valve goes into the right ventricle. The left ventricle can be much smaller and weaker. This can make surgery more complex, and sometimes doctors must consider special operations such as single-ventricle (Fontan-type) pathways.

3. Unbalanced complete AVSD – left-dominant
   In this less common pattern, the left ventricle receives most of the blood, and the right ventricle is small. This also makes repair harder and may need advanced surgical planning to ensure that blood reaches both the lungs and the body in the best way.

4. Complete AVSD with additional heart defects
   Some babies have complete AVSD together with other heart problems, such as narrowing of the outflow to the body (coarctation) or to the lungs, or abnormalities of the great vessels. These extra defects can change symptoms and the timing and type of surgery.

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Causes

These are conditions or risk factors that increase the chance of a baby being born with complete AVSD. In many children, more than one factor may be present, and in some children, no clear cause is found.

1. Down syndrome (trisomy 21)
   Down syndrome is the single most common cause of complete AVSD. Around half of children with complete AVSD have Down syndrome, because the extra chromosome 21 affects how the central heart cushions grow and join together in the embryo.

2. Other chromosome problems (for example trisomy 18 or 13)
   Some babies with other chromosomal syndromes also develop AVSD. The abnormal number or structure of chromosomes can disturb early heart development and lead to holes in the central septum and abnormal valves.

3. Noonan syndrome
   Noonan syndrome is a genetic condition that can affect the heart, face, and growth. Children with Noonan syndrome have a higher chance of AV canal defects, including forms of complete AVSD.

4. Heterotaxy syndromes (abnormal organ arrangement)
   In heterotaxy, organs such as the heart, liver, and spleen are not in their usual positions. This disordered development often affects the central heart structures and can cause AVSD and other complex heart malformations.

5. Isolated gene mutations affecting heart cushions
   Research has found gene changes that affect the endocardial cushions, the tissue that should form the middle of the heart. When these cushions do not grow or fuse correctly, a complete AVSD can form even without a full syndrome like Down syndrome.

6. Family history of congenital heart disease
   Having a close relative with congenital heart disease slightly increases the chance that a baby will have a heart defect, including AVSD. This suggests there is a genetic contribution even when no single gene is known.

7. Maternal diabetes (poorly controlled during pregnancy)
   When a pregnant person has diabetes that is not well controlled, high blood sugar can interfere with organ formation in the baby. This is linked to a higher risk of many congenital heart defects, including AVSD.

8. Maternal rubella or other viral infection early in pregnancy
   Infections like rubella (German measles) during the first trimester can damage the developing heart. This may cause structural defects such as AVSD along with other heart and organ problems.

9. Maternal alcohol use in pregnancy
   Drinking alcohol while pregnant, especially heavy or frequent use, is a known cause of fetal alcohol spectrum disorders and is linked to a higher risk of congenital heart defects, including AVSD.

10. Maternal smoking in pregnancy
    Cigarette smoking can reduce oxygen delivery to the baby and expose the fetus to harmful chemicals. Studies show a modest increase in congenital heart disease, including septal defects, among babies of mothers who smoke.

11. Use of certain medicines in early pregnancy
    Some medicines, especially if taken in high doses or without medical advice in the first trimester, increase the risk of heart defects. Examples include some anti-seizure medicines and high-dose vitamin A derivatives.

12. Maternal phenylketonuria (poorly controlled)
    If a woman with phenylketonuria (PKU) does not control her diet during pregnancy, high phenylalanine levels can harm the developing baby and increase the risk of heart defects such as AVSD.

13. Maternal obesity
    Higher body mass index before pregnancy is linked with a greater chance of some congenital heart defects. Extra weight may be associated with metabolic and inflammatory changes that affect fetal heart development.

14. Low folate or vitamin deficiency before and early in pregnancy
    Poor intake of key vitamins and folic acid before conception and in early pregnancy has been linked to a higher risk of heart defects. Adequate folate seems to lower the risk of several types of congenital heart disease.

15. Exposure to certain industrial chemicals or pesticides
    Parents who work with or live near certain chemicals may have a slightly higher risk of having a child with a heart defect, though the exact chemicals and risk level are still being studied.

16. Uncontrolled thyroid disease in the mother
    Thyroid hormone levels that are too high or too low during early pregnancy may affect the baby’s heart formation and have been linked with congenital heart disease in some studies.

17. Older maternal age
    Older age at pregnancy is associated with a higher risk of chromosomal conditions like Down syndrome, and therefore indirectly increases the chance of AVSD.

18. Consanguinity (parents closely related)
    When parents are blood relatives, recessive gene changes can show up more often in children, which can include genes that affect heart development and raise the chance of AVSD.

19. Previous child with AVSD
    If parents have already had a baby with AVSD, the risk that another baby will have the same or another heart defect is higher than in the general population, suggesting inherited and environmental factors together.

20. Unknown or multifactorial causes
    In many children, no single clear cause can be found. Experts believe that many cases come from a mix of mild genetic tendencies plus small environmental effects that together disturb the normal joining of the endocardial cushions.

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Symptoms and signs

These are common symptoms and clinical signs seen in babies or children with complete AVSD. Not every child has all of them, and the severity can vary.

1. Fast breathing (tachypnea)
   Babies often breathe quickly and may look like they are working hard to breathe, especially when feeding or crying. This happens because extra blood is going to the lungs and the heart is struggling to keep up.

2. Difficulty with feeding
   Feeding may take a long time, and the baby may tire easily or stop before finishing. The extra work of breathing and the weak heart make it hard for the baby to coordinate sucking, breathing, and swallowing.

3. Poor weight gain or failure to thrive
   Because feeding is hard and the body uses more energy to breathe and pump blood, babies may gain weight very slowly or even lose weight. Growth charts may show that they fall behind other children of the same age.

4. Sweating, especially with feeding
   Many babies with heart failure from AVSD sweat a lot on the head and neck when feeding or crying. This is a sign that the body and heart are under stress and working very hard.

5. Bluish color (cyanosis) of lips, tongue, or fingers
   If oxygen-rich and oxygen-poor blood mix and the lungs or heart cannot keep up, parts of the body may look blue or purple. Cyanosis can appear when the baby cries, feeds, or sometimes all the time.

6. Rapid heart rate (tachycardia)
   The heart often beats faster than normal as it tries to move enough blood through the large central hole and leaky valve. This is a common sign of heart failure in infants.

7. Heart murmur
   Doctors can often hear a whooshing or extra sound when listening to the chest with a stethoscope. This murmur comes from turbulent blood flow across the large defect and the abnormal valve.

8. Enlarged liver (hepatomegaly)
   Because the heart is pumping poorly, blood can back up into the veins and the liver can become swollen. A doctor can feel this by gently pressing on the child’s abdomen.

9. Frequent lung infections
   Extra blood flow and pressure in the lungs make infections such as pneumonia or bronchiolitis more likely. Children may get cough, wheeze, and fevers more often than other children.

10. Tiredness and low energy
    Older infants and children may seem less active than others. They may rest often, not want to play, or become tired quickly with normal activity.

11. Swelling of legs, feet, or around the eyes
    In more advanced heart failure, fluid can build up in the body, causing puffiness or swelling. This is less common in very young babies but can occur in older children.

12. Loud or abnormal heart sounds
    On exam, doctors may hear extra heart sounds, a loud second heart sound, or other unusual patterns caused by high pressure in the lungs and mixed blood flow across the defect.

13. Signs of pulmonary hypertension (high lung pressure)
    Over time, high flow and pressure can damage lung vessels, making it even harder for blood to pass through. Children may have more severe breathlessness and sometimes fainting or chest pain with exertion.

14. Developmental delay in some children
    Children with syndromes such as Down syndrome can have both AVSD and developmental delays. Long-term low oxygen or repeated hospital stays can also affect development.

15. No or very mild symptoms in early life (rare)
    Occasionally, symptoms are mild at first, especially if lung pressure is still low or the valve leak is small. However, without treatment, most children with complete AVSD will develop symptoms as the lungs and heart become more stressed.

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Diagnostic tests –

Physical exam

1. General inspection of the child
   The doctor first looks at the baby’s overall condition: breathing pattern, color, weight, and level of alertness. Signs like fast breathing, poor growth, or bluish color raise suspicion of a serious heart defect such as complete AVSD.

2. Cardiac auscultation (listening to the heart)
   Using a stethoscope, the doctor listens for murmurs, extra heart sounds, and how loud the sounds are. In AVSD, there is often a loud murmur and sometimes a widely split second heart sound, suggesting abnormal blood flow between chambers.

3. Lung and breathing examination
   The doctor listens to the lungs for crackles, wheezes, or reduced air entry, and watches how hard the child works to breathe. Crackles and labored breathing can be signs of fluid buildup in the lungs due to heart failure from AVSD.

4. Abdominal and liver examination
   By feeling the abdomen, the doctor checks if the liver is larger than normal, which can be a sign of blood backing up from the failing heart. This helps support the diagnosis of congestive heart failure in the setting of a suspected AVSD.

Manual tests

5. Pulse oximetry (oxygen saturation check)
   A small sensor on the finger or foot measures how much oxygen is in the blood. Lower-than-normal readings or big differences between upper and lower limbs suggest mixing of blood or other structural heart problems.

6. Blood pressure measurement in all limbs
   Measuring blood pressure in both arms and legs helps detect other associated heart problems and gives a picture of how hard the heart and vessels are working. Abnormal pressures can support the suspicion of significant heart disease.

7. Growth and weight charting
   Regularly plotting weight, length, and head size on standard growth charts helps show poor weight gain or failure to thrive. This manual tracking is a simple but important “test” of how much the heart condition is affecting the child’s nutrition and growth.

8. Feeding and activity assessment
   Healthcare workers ask detailed questions about how long feeds take, how the child breathes during feeds, and how active the child is. Observing a feed can give strong clues about heart failure severity in complete AVSD.

Lab and pathological tests

9. Complete blood count (CBC)
   A CBC measures red cells, white cells, and platelets. It can show anemia, infection, or clues of another disorder such as Down syndrome-related blood changes, and helps prepare safely for surgery in children with AVSD.

10. Blood chemistry and organ function tests
    Tests for kidney and liver function, electrolytes, and blood sugar help doctors understand how the child’s body is coping with heart failure and medicines. This information is important for planning surgery and ongoing treatment.

11. Arterial or capillary blood gas analysis
    Blood gas tests measure oxygen and carbon dioxide levels and the acidity (pH) of the blood. Abnormal results can show poor lung function or severe heart failure in a child with suspected AVSD.

12. Genetic testing (karyotype, microarray, or gene panels)
    Because AVSD is strongly linked with chromosomal problems like Down syndrome, doctors often send blood for chromosome testing. More detailed tests such as microarray or gene panels may look for other genetic causes.

Electrodiagnostic tests

13. Standard electrocardiogram (ECG or EKG)
    An ECG records the electrical activity of the heart with skin electrodes. In AVSD it often shows enlargement of both atria and ventricles and sometimes rhythm problems, helping confirm that the heart is under strain.

14. Holter monitor (24-hour ECG recording)
    A Holter monitor is a small portable ECG that the child wears for a day or more. It can detect intermittent rhythm problems or pauses that may not appear on a short ECG in clinic, especially in older children with repaired AVSD.

15. Exercise or stress ECG (in older children)
    For school-age children or teenagers, a stress test on a treadmill or bike with ECG monitoring can show how well the heart responds to exercise and whether arrhythmias or ischemic changes appear. This helps guide activity advice and follow-up after repair.

16. Continuous in-hospital ECG telemetry
    When a child with AVSD is very sick or around the time of surgery, continuous ECG monitoring in the hospital can quickly detect dangerous rhythm changes and guide immediate treatment.

Imaging tests

17. Chest X-ray
    A simple chest X-ray can show an enlarged heart and increased blood flow to the lungs, both of which are common in complete AVSD. It can also reveal fluid in the lungs or other chest problems that affect breathing.

18. Transthoracic echocardiogram (heart ultrasound)
    This is the main test for diagnosing AVSD. A probe on the chest uses sound waves to create moving pictures of the heart, showing the big central hole, the common AV valve, the direction of blood flow, and lung pressures.

19. Fetal echocardiogram (before birth)
    Special ultrasound of the baby’s heart during pregnancy can detect AVSD before delivery. Early diagnosis allows planning for birth at a center with pediatric cardiology and surgery, which improves safety for the newborn.

20. Cardiac catheterization and angiography
    In this invasive test, a thin tube is passed through blood vessels into the heart to measure pressures and oxygen levels. Contrast dye can outline the holes and valve in detail. Catheterization is used when echo images are not clear enough or when surgical planning needs very precise information.

Non-pharmacological treatments (therapies and other care)

1. Care by a pediatric cardiology team
   A baby with complete AVSD should be followed by a pediatric cardiologist and a heart team in a center that knows congenital heart disease very well. They check breathing, weight gain, heart sounds, oxygen levels, and test results such as echocardiograms. The purpose is to time surgery correctly and adjust all treatments early. This close follow-up helps prevent severe heart failure and lung damage.

2. Frequent monitoring and echocardiography
   Regular heart ultrasound (echo) shows how big the hole is, how much blood is leaking through the common valve, and how well the ventricles pump. Doctors also watch lung artery pressure. The purpose is to see whether heart failure is getting worse and to plan surgery and medicines. Echo is painless and safe and is the main imaging test for AVSD.

3. Optimized feeding and high-calorie nutrition
   Babies with complete AVSD burn a lot of energy because breathing and circulation cost more effort. They often cannot drink enough milk to gain weight. Dietitians may add calories to breast milk or formula and may suggest smaller, more frequent feeds or feeding through a tube. The purpose is to help the baby gain enough weight and strength before surgery.

4. Feeding support tools (bottles, nipples, or feeding tubes)
   Special nipples, slower-flow bottles, or nasogastric feeding tubes can make feeding easier and less tiring. The goal is to reduce the baby’s work during feeding so breathing stays easier and calories are used for growth, not just for breathing. A speech or feeding therapist may teach techniques to make swallowing safer and more efficient.

5. Careful fluid management (non-drug side)
   Nurses and doctors carefully track how much fluid the baby drinks and how much urine comes out. They may slightly limit fluids if there is severe heart failure and fluid overload. The purpose is to avoid extra stress on the lungs and reduce swelling. This works together with diuretic medicines but also includes simple measures like weighing the baby daily.

6. Oxygen and respiratory support when needed
   Some babies need extra oxygen, or short periods on breathing support devices, if they are very breathless or have lung infections. The aim is to keep oxygen levels safe and lower the work of breathing. Too much oxygen can sometimes increase blood flow to the lungs, so it must be carefully controlled by specialists.

7. Infection prevention and good hygiene
   Respiratory infections, like RSV or influenza, can be very dangerous for a baby with heart failure. Hand-washing, masks during outbreaks, avoiding crowded places, and making sure close contacts are vaccinated help prevent illness. Some babies may receive special injections (such as RSV monoclonal antibodies) during viral seasons if the cardiologist recommends it.

8. Early treatment of lung infections
   If a baby with AVSD develops cough, fast breathing, or fever, early evaluation and treatment of pneumonia or bronchiolitis is vital. Rapid antibiotics or antiviral care can stop extra stress on the heart and lungs. The purpose is to avoid a dangerous spiral of worsening heart failure triggered by infection.

9. Positioning to ease breathing
   Simple things like holding the baby slightly upright, not flat, and using safe sleep positions recommended by the doctor can reduce pressure on the lungs and make breathing easier. Parents are trained in safe methods so that the baby can rest with less work of breathing.

10. Energy-saving daily routines
    Families learn to plan care so the baby is not over-tired. Short, calm play times, gentle handling, and allowing frequent rest can lower the body’s energy use. This helps preserve calories for growth and keeps symptoms like sweating and fast breathing under better control.

11. Psychological and social support for family
    Having a child with a serious heart defect is very stressful. Social workers, psychologists, and support groups help parents cope with fear, hospital stays, and financial strain. Emotional support indirectly improves the child’s care, because calmer parents can follow complex treatment plans more easily.

12. Pre-operative optimization programs
    Before surgery, teams often follow structured care plans: correcting anemia, checking kidney and liver function, reviewing medicines, and giving all needed vaccines. The purpose is to make surgery safer and reduce complications. These programs come from congenital heart disease guidelines and hospital protocols.

13. Cardiac rehabilitation and gentle activity after surgery
    As the child grows, doctors usually encourage appropriate physical activity. Over time, many children can play and exercise with reasonable limits. Carefully supervised activity improves fitness, mood, and appetite. The purpose is to strengthen muscles and lungs while respecting any heart or valve limitations.

14. Neurodevelopmental follow-up
    Children with complex congenital heart disease can have learning or developmental challenges later, especially after neonatal heart surgery. Follow-up with developmental specialists, physical therapists, and occupational therapists can detect delays early and give extra help. This supports long-term quality of life.

15. Dental care and endocarditis prevention education
    Good dental hygiene, regular brushing, and professional dental visits are important. For some high-risk heart conditions or certain surgeries, antibiotics may be recommended before major dental work to reduce the risk of heart valve infection (endocarditis). Parents learn which procedures need extra protection according to current guidelines.

16. Genetic counseling for the family
    Complete AVSD is more common in children with Down syndrome and sometimes other genetic syndromes. Genetic counseling can explain recurrence risk in future pregnancies and options for prenatal testing. It can also connect families with early-intervention services linked to genetic conditions.

17. Prenatal diagnosis and planning
    If AVSD is seen on fetal ultrasound, families can be referred to a fetal cardiology center. The team plans delivery in a hospital with surgical and intensive care services for newborns with heart disease. This advanced planning is non-drug care that greatly improves safety right after birth.

18. Education about warning signs at home
    Parents are taught to watch for rapid breathing, poor feeding, color changes, extreme sleepiness, or swelling. They learn when to call the doctor or emergency services. This “home monitoring” is a very important non-pharmacological safety tool.

19. Vaccination according to schedule
    Keeping routine childhood vaccines up to date, including influenza and other recommended vaccines, protects the child from infections that would strain the heart. In many guidelines, children with serious congenital heart disease are placed in a higher-priority group for some vaccines.

20. Long-term lifestyle counseling as the child grows
    Later in life, healthy weight, no smoking, regular exercise, and control of blood pressure and diabetes become important to protect the repaired heart and valves. Counselors explain age-appropriate lifestyle habits from childhood through adulthood.

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Drug treatments – general notes and safety

Medicines for complete AVSD do not close the hole or cure the defect. They support the heart and lungs before and after surgery. Most drug use is based on general pediatric heart failure experience, not on large trials in AVSD alone.

Because the patient is usually a baby or small child, all doses are calculated very carefully by weight, kidney function, and clinical status. For safety reasons, I will not give exact dose numbers or timing schedules here. Those must always be decided by a pediatric cardiologist. The information below explains classes, purposes, basic mechanisms, and important side-effects.

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Key drug treatment options

1. Loop diuretics (for example, furosemide)
   Loop diuretics make the kidneys pass more salt and water, which reduces lung congestion and swelling. They are often the first medicine used when heart failure causes rapid breathing and poor feeding. Furosemide is approved for edema in adults and children with heart failure in official labeling. Common side-effects include dehydration, low potassium, and changes in kidney function, so blood tests are needed.

2. Thiazide diuretics (for example, hydrochlorothiazide)
   Sometimes a second diuretic from the thiazide group is added when a loop alone is not enough. Thiazides act on a different part of the kidney tubule and help remove extra fluid. They can improve symptoms but may lower sodium and potassium levels. They are usually used for a short period under close monitoring.

3. Potassium-sparing diuretics (for example, spironolactone)
   Spironolactone blocks aldosterone and helps the body keep potassium while still getting rid of salt and water. It is used as an add-on drug in some heart failure patients and has been shown to reduce deaths in severe adult heart failure. Main side-effects are high potassium levels and, in adults, breast tenderness; so potassium and kidney function must be watched.

4. ACE inhibitors (for example, captopril, enalapril)
   ACE inhibitors relax blood vessels and reduce the workload on the heart by blocking the renin–angiotensin–aldosterone system. Labels and reviews show benefit in heart failure and left-ventricular dysfunction, although pediatric data are more limited. They can improve symptoms and long-term heart function. Side-effects include low blood pressure, cough, kidney problems, and high potassium.

5. Angiotensin receptor blockers (for example, valsartan in some older patients)
   ARBs block angiotensin II at its receptor and are sometimes used when ACE inhibitors are not tolerated. They have similar benefits and side-effects, including possible low blood pressure and high potassium. They are generally used in older children or adults with repaired AVSD and persistent heart failure.

6. Digitalis glycosides (for example, digoxin)
   Digoxin makes the heart pump more strongly and can slow certain fast heart rhythms. It is approved for pediatric heart failure and for controlling heart rate in some arrhythmias. It may be used in selected infants with AVSD who have poor pumping function or atrial flutter. Too much digoxin can cause nausea, vomiting, and dangerous heart rhythms, so levels are monitored.

7. Beta-blockers (for example, carvedilol in selected cases)
   In some older infants or children, beta-blockers are used to slow the heart, reduce oxygen demand, and improve long-term remodeling. Evidence is stronger in adults, but pediatric heart failure guidelines sometimes include carvedilol as an option. Side-effects include low blood pressure, slow heart rate, and tiredness.

8. Inotropes (for example, milrinone, dopamine – short-term in ICU)
   During severe decompensated heart failure or right after surgery, inotropes may be given intravenously in the intensive care unit. They increase the strength of heart contraction and can reduce lung pressures (milrinone). Because of risks such as low blood pressure and arrhythmias, they are short-term, hospital-only medicines.

9. Pulmonary vasodilators (for example, sildenafil, bosentan in selected patients)
   If pulmonary hypertension persists, specialists may use medicines that relax the blood vessels in the lungs. The goal is to lower lung pressure and protect the right ventricle. These drugs require expert centers because they can worsen shunting if used wrongly. They are not routine for all AVSD patients.

10. Anticoagulants (for example, warfarin, heparin – after certain surgeries or valves)
    Some children with mechanical valves, arrhythmias, or clots after surgery need blood thinners to prevent stroke or valve thrombosis. Doses are adjusted after repeated blood tests (INR for warfarin). The main risk is bleeding, so parents get careful instructions about injuries and other medicines.

11. Antiplatelet drugs (for example, low-dose aspirin in selected cases)
    Low-dose aspirin may be used after some surgical repairs, especially if there is a synthetic patch or certain valve repairs. It reduces platelet stickiness and can lower clot risk. The dose is much smaller than adult pain doses and must be set by the cardiologist. Side-effects include stomach irritation and, rarely, bleeding.

12. Antiarrhythmic medicines (for example, amiodarone or others if serious rhythm issues)
    If the child develops serious arrhythmias after surgery, antiarrhythmic drugs may be needed. These medicines regulate heart rhythm but can have many side-effects on thyroid, lungs, or liver, so they are used with strong monitoring.

13. Antibiotics (for infections and sometimes for endocarditis prophylaxis)
    Antibiotics treat pneumonia, sepsis, or wound infections, which are especially dangerous in AVSD patients. In a few high-risk situations, antibiotics may also be used before major dental or surgical procedures to lower endocarditis risk, following guideline criteria.

14. Pain control medicines after surgery (paracetamol, limited opioids)
    Good pain control after open-heart surgery helps the child breathe deeply and move earlier, lowering the risk of pneumonia and blood clots. Doses are carefully calculated for age and weight.

15. Sedation medicines in ICU (for example, midazolam, morphine – short-term)
    These medicines keep very sick babies calm while on ventilators or after complex surgery. They reduce stress hormones and oxygen demand. Use is short-term and highly monitored to avoid dependence or breathing problems.

16. Gastric protection (for example, proton pump inhibitors or H2 blockers) when needed
    Stress, steroids, and some medicines can irritate the stomach. In the ICU or during long treatments, stomach-protecting drugs may be given to prevent ulcers or bleeding. They are normally stopped when the child is stable.

17. Iron and anemia treatment (if low hemoglobin)
    If the child has anemia, iron or other treatments may be used, because very low hemoglobin makes the heart work harder to carry oxygen. However, unnecessary iron in children with certain heart problems can be harmful, so tests are done first.

18. Vitamin D and calcium in selected patients
    If a child is on long-term diuretics or has limited feeding, vitamin D and calcium may be recommended to protect bone health and general growth, under pediatric guidance.

19. Anti-reflux medicines (for babies with feeding and reflux problems)
    Some infants with AVSD have reflux that makes feeding painful and worsens breathing. Medicines that reduce stomach acid can make feeding easier and reduce the risk of aspiration into the lungs.

20. Specialized drugs in research or rare situations
    Some children with complex forms of AVSD, genetic syndromes, or severe pulmonary hypertension may enter clinical trials or receive newer medicines. These are always managed by specialized centers and research teams and are not routine treatments.

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Dietary molecular supplements

Supplements are not a primary treatment for AVSD. They may support general health in some children, but every supplement should be discussed with the cardiologist because some products contain extra salt, sugar, or stimulants. Examples of nutrients doctors sometimes consider (only when needed) include:

1. Energy-dense formula additives (modular carbohydrates or fats) – used to increase calories without making the feed volume too large.

2. Protein supplements – to support growth when total intake is low.

3. Iron – if tested and found to be iron-deficient.

4. Vitamin D – if the child has low levels or poor sun exposure.

5. Calcium – when bone health is at risk, especially with long-term diuretics.

6. Omega-3 fatty acids (fish oil) – sometimes used for general heart and brain health, but evidence in congenital heart disease is limited.

7. Multivitamin drops – to cover small micronutrient gaps in picky eaters.

8. Electrolyte-balanced oral rehydration solutions – during mild illness, if approved by the cardiologist.

9. Pre- and probiotics – occasionally used to support gut health during or after antibiotics.

10. Special disease-specific formulas (for example, low-salt formulas) – in some heart failure situations, to reduce sodium and fluid retention.

All of these must be chosen by the child’s medical team; giving “heart supplements” on your own can be unsafe.

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Immunity-supporting and regenerative / stem cell approaches – current reality

1. Routine vaccines
   Vaccines against influenza, pneumococcus, and other standard childhood diseases are one of the most important “immunity boosters” for children with complete AVSD. They help prevent infections that could lead to severe heart failure episodes.

2. Targeted infection-prevention medicines (for example, RSV monoclonal antibodies)
   In some countries, high-risk infants with serious heart disease may receive monoclonal antibodies during RSV season to reduce the chance of severe lung infection. This is not a classic “immune booster,” but it is a powerful protective tool.

3. Nutritional support for immune health
   Adequate calories, protein, vitamins, and minerals (especially iron, zinc, and vitamin D) are essential for a healthy immune system. Malnutrition makes infections more frequent and more severe.

4. Experimental stem cell and regenerative therapies (not standard care for AVSD)
   Stem cell and regenerative medicine strategies are being studied for some forms of congenital heart disease, often in conditions like hypoplastic left heart syndrome, to help strengthen heart muscle or improve function. Early trials show safety but are still in research phases and not routine treatments for AVSD.

5. Tissue engineering and future valve repair options
   Scientists are exploring tissue-engineered valves and patches that grow with the child, which could reduce repeat surgeries in congenital heart disease. These approaches are promising but largely experimental.

6. Gene and cell-based therapies in very early research
   Some research groups are studying gene editing and advanced cell therapy for congenital defects, but at present these are only available in highly controlled clinical trials, not as routine “regenerative drugs” for complete AVSD. Families should be wary of any clinic claiming miracle stem-cell cures outside recognized research programs.

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Surgical treatments –

1. Complete AVSD repair (two-patch technique)
   This is the standard surgery for many complete AVSDs. The surgeon uses patches to close the hole in the atrial septum and the ventricular septum separately and reconstructs the single common valve into two valves. The aim is to restore normal blood flow between the heart chambers and reduce valve leakage. Most centers report good survival and long-term outcomes with this method.

2. Single-patch or modified single-patch repair
   Some surgeons use a single patch to close both the atrial and ventricular components and rebuild the common valve. The choice between one-patch and two-patch techniques depends on the anatomy and the surgeon’s experience. Studies compare these methods to see which gives better valve function and lower leak rates.

3. Valve cleft closure and atrioventricular valve repair
   During repair, surgeons close abnormal splits (“clefts”) in the valve leaflets and reshape the valve so it closes better. This step is critical, because long-term problems often come from valve leakage rather than the patches. Sometimes later re-operations are needed if valve regurgitation becomes severe again.

4. Pulmonary artery banding (palliative surgery before full repair in select cases)
   In some small or unstable babies, an initial palliative procedure is done. A band is placed around the pulmonary artery to limit blood flow to the lungs and reduce heart failure. Later, when the child is bigger and stronger, the full AVSD repair is performed and the band is removed.

5. Re-operations and valve replacement in older children or adults
   If repaired valves leak severely or if there are residual holes, later surgeries may be needed. In some older patients, a mechanical or bioprosthetic valve may be placed. After mechanical valve replacement, lifelong anticoagulation is usually needed.

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Prevention and risk reduction

Complete AVSD cannot always be prevented, but some risk factors can be reduced:

1. Good control of maternal illnesses such as diabetes before and during pregnancy.

2. Avoiding alcohol, smoking, and harmful drugs in pregnancy.

3. Vaccination against rubella and other infections before pregnancy when recommended.

4. Reviewing all medicines with a doctor before and during pregnancy.

5. Folic acid and good maternal nutrition as advised before conception.

6. Genetic counseling if there is a family history of congenital heart disease or Down syndrome.

7. Regular prenatal care and recommended ultrasounds so heart defects can be detected early.

8. Delivering high-risk pregnancies in centers with neonatal cardiac services.

9. After birth, preventing respiratory infections through hygiene and vaccines.

10. Lifelong follow-up to prevent late complications like pulmonary hypertension or valve failure.

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When to see a doctor or go to emergency care

You should seek urgent medical help if a baby or child with complete AVSD has any of these signs:

• Very fast or difficult breathing, flaring nostrils, grunting, or chest pulling in.

• Skin, lips, or tongue turning blue or gray.

• Refusing feeds or drinking much less than usual.

• Vomiting with inability to keep fluids down.

• Very poor weight gain or sudden weight loss.

• Extreme sleepiness, limpness, or not waking for feeds.

• New swelling of legs, feet, belly, or eyelids.

• High fever or signs of serious infection.

• Fainting, seizure-like episodes, or sudden collapse.

• Any sudden change that worries you, even if not on this list.

For non-urgent concerns (mild feeding issues, slow weight gain, scheduled follow-up), parents should contact the pediatric cardiologist or clinic promptly for advice.

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What to eat and what to avoid

Diet is always individualized and should follow the cardiologist’s and dietitian’s advice, especially in babies. General ideas:

1. Focus on breast milk or appropriate infant formula – best base nutrition for infants unless the doctor advises special formula.

2. Use high-calorie fortifiers when prescribed – adds energy without large volume so the baby uses fewer breaths per feed.

3. Offer frequent, small feeds – easier for babies who tire quickly.

4. For older children, give balanced meals – including fruits, vegetables, whole grains, and lean proteins.

5. Limit extra salt – high-salt foods (chips, canned soups, salty snacks) can worsen fluid retention in some heart failure patients.

6. Avoid sugar-only drinks – like sodas and energy drinks; they add calories but no nutrients and can upset fluid balance.

7. Avoid herbal or “heart tonic” supplements without medical approval – some affect blood pressure, bleeding, or liver function.

8. Watch total fluid if the doctor has set a limit – use measuring cups and keep a daily record if told to do so.

9. Avoid excessive caffeine in older children or teens – energy drinks or strong tea/coffee can increase heart rate and blood pressure.

10. Seek help early if feeding is stressful – feeding therapists and dietitians can adjust textures, schedules, and supplements to make things safer and easier.

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Frequently asked questions (FAQs)

1. Can medicines alone cure complete atrioventricular septal defect?
   No. Medicines can ease symptoms and help the baby grow, but they cannot close the hole or fix the valve. Surgery is needed to repair a complete AVSD.

2. At what age is surgery usually done?
   Most sources recommend repair in early infancy, commonly between 2 and 6 months of age, and before 6 months whenever possible, to prevent permanent lung damage. The exact timing depends on symptoms, heart anatomy, and the center’s practice.

3. Is surgery safe?
   Any open-heart surgery has risks, but results have improved a lot. Many centers report survival rates over 90% for uncomplicated complete AVSD repair. Long-term follow-up is still needed to monitor valves and heart function.

4. Will my child need more than one surgery?
   Some children need later operations to repair or replace leaky valves or fix residual holes. Others may do well with only one major operation. Regular cardiology visits are essential to watch for new problems.

5. Can my child live a normal life after repair?
   Many children with repaired AVSD attend school, play, and have good quality of life. Some may have limits in very hard sports or may need medicine for rhythm or valve issues. Lifelong follow-up is important.

6. Is complete AVSD linked to Down syndrome?
   Yes. Complete AVSD is common in children with Down syndrome, but it can also occur without any genetic syndrome. Genetic testing and counseling can explain this in more detail.

7. Can I prevent future pregnancies from having AVSD?
   You cannot guarantee prevention, but good prenatal care, avoiding harmful substances, and genetic counseling after having one affected child can help you understand and reduce risk where possible.

8. Why does my baby breathe so fast?
   The hole and valve leak send extra blood to the lungs, causing congestion and fluid build-up. The lungs have to work harder, so breathing becomes fast and sometimes noisy. Diuretics, careful feeding, and surgery help improve this.

9. Why is weight gain slow?
   Feeding is hard work when breathing is fast, and the body burns many calories just to stay stable. High-calorie feeds and supportive care help, but for many babies weight gain really improves after surgical repair.

10. Will my child always need medicines after surgery?
    Some children need heart medicines (for example, ACE inhibitors or diuretics) for a while after surgery, and a few need them long term. Others may be able to stop most drugs when heart function and valves are stable. The cardiologist decides this case by case.

11. Can my child play sports?
    Many children with repaired AVSD can play non-competitive or moderate sports. Very intense or collision sports may need special evaluation. The cardiologist will usually recommend an exercise test or ECG/echo before clearing high-level sports.

12. Is pregnancy safe later for a person born with AVSD?
    Some women with a repaired AVSD can have safe pregnancies, but they need pre-pregnancy counseling and close care from adult congenital heart disease specialists. Valve problems, pulmonary hypertension, or poor heart function can make pregnancy risky.

13. Are stem cell or gene therapies available now for AVSD?
    No standard stem cell or gene therapy is approved to treat complete AVSD. These approaches are still being studied in research trials for some congenital heart diseases. If you see clinics offering “cures” without trials, be very cautious.

14. Does my child need antibiotic prophylaxis for dental work?
    Some patients who have certain valve repairs or prosthetic material may need antibiotics before invasive dental procedures to reduce endocarditis risk. The cardiologist will give a written plan if this applies to your child.

15. Where can I learn more and find support?
    Large congenital heart centers, national heart foundations, and reputable hospital websites offer patient-friendly information and family support groups for AVSD and other congenital heart defects. Your cardiologist can point you to organizations that are trustworthy and up to date.

Disclaimer: Each person’s journey is unique, treatment plan, life style, food habit, hormonal condition, immune system, chronic disease condition, geological location, weather and previous medical  history is also unique. So always seek the best advice from a qualified medical professional or health care provider before trying any treatments to ensure to find out the best plan for you. This guide is for general information and educational purposes only. Regular check-ups and awareness can help to manage and prevent complications associated with these diseases conditions. If you or someone are suffering from this disease condition bookmark this website or share with someone who might find it useful! Boost your knowledge and stay ahead in your health journey. We always try to ensure that the content is regularly updated to reflect the latest medical research and treatment options. Thank you for giving your valuable time to read the article.

The article is written by Team RxHarun and reviewed by the Rx Editorial Board Members

Last Updated: February 27, 2025.