1.What is congenital heart disease?
Congenital heart disease (congenital heart disease for short) refers to the abnormalities of cardiovascular structure and function that exist at birth. It is a structural or cardiovascular malformation of the heart caused by abnormal or impaired cardiovascular development during fetal life and failure to degenerate the tissues that should degenerate after birth.
2.Why do you get precocious heart disease?
The causes of precardiac disease are broadly divided into two categories: endogenous and exogenous.
Endogenous factors are genetic factors, such as chromosomal abnormalities and genetic aberrations. About 4% to 5% of precocious heart disease is caused by chromosomal disease.
The more important exogenous factors are viral infections, especially rubella, mumps, influenza and coxsackievirus. The critical period of heart embryonic development is from the 2nd to 8th week of gestation, and the main cause of cardiovascular malformations occurs during this period. The incidence of precocious heart disease is higher in newborns born to mothers with severe viral infections during the third trimester, especially rubella virus. Secondly, fetal environmental and maternal factors, including local mechanical compression around the fetus, nutritional or vitamin deficiencies of the mother, can affect the fetal heart development. Other factors such as highland areas, where the incidence of ductus arteriosus is higher, may be related to hypoxia in the highlands. Other factors such as the mother’s exposure to high doses of X-rays or use of certain drugs during pregnancy, suffering from chronic diseases, hypoxia, the mother’s advanced pregnancy, abortion preservation and multiple births are all high-risk factors.
3.What are the manifestations of precordial disease?
Precocious heart disease with small defects and minor malformations are mostly like normal people and can have no symptoms at all. However, the main manifestations of severe precardiac disease, such as large ventricular septal defect, large arteriovenous catheter failure and complex precardiac disease are cyanosis, abnormal breathing and hypoxic attacks.
(1) Cyanosis: It is often the only symptom of severe precordial disease, and is often progressively worse. Cyanosis should be examined under well-lit conditions, when the child is quiet or sleeping and when the extremities are warm. Those who have obvious cyanosis immediately after birth mostly have large-vessel misalignment and tricuspid atresia, while those with tetralogy of Fallot and ectopic pulmonary venous drainage tend to develop cyanosis gradually after the neonatal period.
(2) Respiratory abnormalities: they are often short and labored, especially when feeding, which often makes feeding difficult. Due to shortness of breath, there are intermittent pauses during breastfeeding and easy choking. Respiration is faster, even in a quiet state, exceeding 60 breaths/min.
(3) Hypoxic attack: Sudden irritability, increased cyanosis, deep and fast breathing, confusion, fainting and convulsions in severe cases, and diminished or absent heart murmurs during feeding or defecation, which can last from a few minutes to several hours. It is mostly seen in cyanotic precordial disease, such as tetralogy of Fallot, tricuspid atresia, etc. In non-cyanotic preconditioning, pallid episodes may also occur, manifested by paroxysmal crying, pallor, cold sweating, curling of the limbs, shortness of breath, and in severe cases, fainting, mostly due to temporary cerebral hypoxia caused by insufficient left ventricular blood displacement, such as aortic valve, severe stenosis of the mitral valve, three-chamber heart and left-to-right shunt preconditioning.
4. What are the risks of precordial disease?
The incidence of precordial disease accounts for about 0.7~0.8% of the total number of newborn babies. About 20% to 50% of the children die within one year of age, while others survive, but as they grow older, the abnormal hemodynamics will lead to cardiovascular malformations, which can easily lead to pneumonia, heart failure, shortness of breath, easy fatigue, syncope, chest pain, and so on, which can cause serious harm to the patient, and as a result, the best opportunity for surgery is lost. Some children are treated surgically, but eventually the risk and complication rate of surgery increases significantly due to the severity of secondary lesions.
Hazard 1: Half of the children with untreated precardiac disease die by age 1 and two-thirds by age 2. And the more complex the malformation, the more severe the condition the more death and the earlier death.
Hazard 2: Blood turbulence caused by abnormal heart structure can cause damage to the local endocardial structure, which can easily harbor bacteria. Bacteria may make their “home” in the heart and grow and multiply, aggravating the damage to the heart and causing infective endocarditis.
Hazard 3: Ischemia and hypoxia in children with precordial disease may result in sudden respiratory distress, increased bruising, unconsciousness, convulsions, and affect the blood supply to the brain. Long-term severe ischemia and hypoxia will lead to the decline of intelligence of the affected children.
Hazard 4: The flow and deformation of blood and blood vessels increase the burden on the heart and cannot meet the normal needs. Insufficient blood perfusion of organs and tissues occurs heart failure and induces malignant arrhythmia or even sudden death.
5. Can children with precocious heart disease receive normal preventive vaccination?
Some children with precardiac disease are weak and may be combined with low immunity, and there is a possibility that some live attenuated vaccines may cause infective endocarditis. Therefore, it is generally accepted that vaccination of children with precocious heart disease must be done with caution. Live attenuated vaccines should be selected on a case-by-case basis. Inactivated vaccines are generally the best choice.
Some experts also consider cyanotic congenital heart disease, a contraindication to vaccination. Other types of congenital heart disease should be treated differently depending on the child’s heart function and the type of vaccine. If the child’s heart function is good and growth and development are normal, he or she can receive those vaccines that are less reactive and safer, such as polio pill vaccine and hepatitis B vaccine. Some vaccinations can be postponed from the normal vaccination time.
6.How can parents detect children with precocious heart disease at an early stage?
After birth, if the child is found to have the following conditions, the child has a higher possibility of developing precocious heart disease.
(1) The appearance of cyanosis: the skin continues to appear cyanotic, most obvious at the tip of the nose, lips, and nail roots of the fingers and toes. Some children have persistent cyanosis after birth, while others have progressively more pronounced cyanosis three to four months after birth.
(2) Heart murmur: normal pediatric heartbeat like a pendulum, two groups of two sounds, each one is very clear, if the child’s chest heard between the two sounds there is a blowing wind-like, machine-starting-like sound, some chest can feel the tremor. This means that there may be precordial disease.
(3) Poor physical strength: infants have difficulty feeding or refusing to eat, choking and coughing, often eating and stopping, shortness of breath, pale face, breath-holding, etc.
(4) susceptible to respiratory infections: most precardiac disease due to increased pulmonary blood, usually susceptible to repeated respiratory infections, further leading to cardiac failure, the two are often causal to each other as the cause of death in precardiac disease.
(5) poor development: normal children within one year of age in the first six months of weight growth of 0.6 kg per month, the last six months of monthly growth of 0.5 kg. Weight growth below this rate indicates stunted development.
(6) squatting: infants and toddlers hold when the legs are not straight, but like to bend in the abdomen of adults, sitting like to lift the feet to the stool surface, standing when the lower limbs to maintain a bent posture. Older children walking, walking for a period of time to squat down two knees close to the chest to rest for a moment, medically known as squatting phenomenon.
(7) Other: hoarse crying, shortness of breath, coughing since childhood; elevation of the precordial region, thoracic deformity. Older children may complain of chest tightness, pain in the precordial region, and panic, and these symptoms are more pronounced especially after activity. Some children may also have swelling of the lower extremities.
If parents find that their children have the above symptoms, they should go to the hospital early to find out if they have precordial disease.