Congenital heart disease is the most common type of congenital malformation, accounting for about 28% of all kinds of congenital malformations. It refers to the anatomical structure abnormalities caused by the formation disorders or abnormal development of the heart and large blood vessels during embryonic development, or the failure to close the channels that should be closed automatically after birth (which is normal in the fetus). The incidence of congenital heart disease is not to be underestimated, accounting for 0.4% to 1% of births, which means that 150,000 to 200,000 new patients with congenital heart disease are born in China every year. The spectrum of congenital heart disease is particularly broad, including hundreds of specific subtypes, some patients can be combined with a variety of malformations at the same time, the symptoms vary widely, the lightest can be asymptomatic for life, and the severe symptoms such as hypoxia, shock and even premature death at birth. According to the hemodynamic and pathophysiological changes, congenital heart disease can be classified as cyanotic or non-cyanotic, and can also be divided into three categories according to the presence or absence of shunts: no shunt (e.g. pulmonary stenosis, aortic constriction), left-to-right shunt (e.g. atrial septal defect, ventricular septal defect, patent ductus arteriosus) and right-to-left shunt (e.g. tetralogy of Fallot, large vessel dislocation).
A small number of patients with congenital heart disease have a chance of self-healing before the age of 5 years, and a small number of patients with mild malformations that do not significantly affect circulatory function and do not require any treatment, but most patients require surgical treatment to correct the malformations. With the rapid development of medical technology, the effect of surgery has been greatly improved. At present, most patients can recover as normal as normal people if they are treated with surgery in time, and their growth and development will not be affected, and they can be able to perform ordinary work, study and life needs.
I. Etiology
It is generally believed that early pregnancy (5-8 weeks) is the most important period of fetal heart development, and there are many reasons for the development of congenital heart disease, genetic factors only account for about 8%, while the vast majority of 92% are caused by environmental factors, such as drugs, viral infections, environmental pollution, radiation and other factors that can cause abnormal fetal heart development. In particular, rubella virus infection in the first trimester of pregnancy can sharply increase the risk of congenital heart disease in children.
II. Clinical manifestations
There are many types of congenital heart disease, and their clinical manifestations mainly depend on the size and complexity of the malformation. Complex and severe malformations can show serious symptoms shortly after birth and even become life-threatening. It should be noted that some simple malformations such as ventricular septal defect and patent ductus arteriosus can have no obvious symptoms in the early stage, but the disease can still potentially develop and worsen, and need timely diagnosis and treatment to avoid losing the opportunity of surgery. The main symptoms are.
1. Frequent colds, recurrent respiratory infections and susceptibility to pneumonia.
2. Poor growth and development, wasting and excessive sweating.
3.Impotent sucking during breastfeeding, difficulty in feeding, or infant refusing to eat, choking and coughing, and shortness of breath in general.
4.Children complain of easy fatigue and poor physical strength.
5.Blue lips and nails or bruising after crying or activity, pestle-shaped fingers and toes (nail bed bulging like a hammer).
6.Like squatting, fainting, hemoptysis.
7. Auscultation reveals a heart murmur.
III. Diagnosis
The diagnosis is usually made by symptoms, signs, ECG, X-ray and echocardiography, and the hemodynamic changes, degree and extent of lesions can be estimated to determine the treatment plan. For congenital heart disease with multiple malformations and complex and difficult cases, the specialist will selectively take 3D CT examination, cardiac catheterization or cardiovascular angiography to understand the degree, type and scope of the lesion, make a clear diagnosis and guide the formulation of treatment plan according to the situation.
IV. Treatment
1.Only a few types of congenital heart disease in general can recover naturally, while some will gradually increase in complications and get worse as they get older.
The choice of treatment has been the right time to choose the surgery, mainly depends on the scope and degree of congenital heart malformation. Simple and mild anomalies such as atrial septal defect and simple pulmonary valve stenosis, if the diameter of the defect is small, have no significant hemodynamic impact and can be treated without any treatment for life. Severe congenital heart disease such as complete transposition of the great arteries or hypoplastic left heart syndrome must be operated immediately after birth, otherwise the child will not survive.
2.Conservatively observed cases of congenital heart disease.
(1) Secondary foramen ovale defect with small diameter and no tendency of pulmonary hypertension can be observed until 3 to 5 years of age before surgery.
(2) Membranous ventricular septal defect less than 4 mm in diameter has a mild effect on cardiac function and has the possibility of automatic closure, so it can also be observed until 3 to 5 years of age, and surgery should be considered if the ventricular defect still fails to close. Since small ventricular defects have the potential to induce bacterial endocarditis, and the safety of surgical procedures is currently very high, it is not recommended to wait for a longer period of time.
(3) Aortic valve with transvalvular pressure difference less than 40 mmHg and pulmonary valve stenosis less than 60 mmHg. The prerequisite for conservative treatment in these cases is that the heart must be examined by ultrasound more than twice in a hospital with a high level of precordial surgery, and that regular follow-up observations and necessary examinations are required during the observation period to avoid misdiagnosis and delay in treatment.
3, choose the appropriate timing of surgery is the key to successful surgery and achieve a good prognosis of precordial disease.
At present, there are several main factors to determine the timing of surgery.
(1) The pathological characteristics of the preconditioning itself and the degree of impact on hemodynamics Generally speaking, the more complex the malformation, the greater the impact on hemodynamics, the more early the surgery should be treated.
(2) Progression of secondary pathological changes In left-to-right shunt type of precardiac disease, surgical correction should be sought before the development of obstructive pulmonary vascular changes. Cyanotic, obstructive congenital heart disease should strive for surgery before the occurrence of severe myocardial hypertrophy and fibrous degeneration.
4.Treatment methods of congenital heart disease.
There are various kinds of surgical treatment, interventional treatment and drug treatment. The choice of treatment and the most appropriate time for surgery should be based on the condition, and the cardiologist should make recommendations according to the specific situation of the child. The non-shunt or left-to-right shunt category has a good outcome and a good prognosis after timely surgery. For those with right-to-left shunt or compound malformation, the surgery is complicated and difficult in more severe cases, and some patients cannot be completely corrected due to imperfect development of certain cardiac structures, so only palliative surgery can be performed to alleviate symptoms and improve the quality of life.
Interventional treatment is broadly divided into two categories: one is the use of balloon dilation to release the stenosis of blood vessels and valves, such as aortic stenosis, pulmonary stenosis, aortic constriction, etc.; the other is the use of a variety of special blockers made of memory metal to close the undesirable defects, such as atrial septal defect, ventricular septal defect, arterial catheter closure, etc. Due to the progress of medical technology and the continuous research and improvement of materials and processes, interventional treatment is now further developed in domestic and international clinical applications, which not only can avoid the risk and trauma of open-heart surgery, but also has short hospitalization time and fast recovery, and is a very effective treatment method. Interventional therapy has partially replaced but not completely replaced surgical open-heart surgery, and the technique has strict indications.
The surgical methods for precardiac disease are determined by a combination of factors such as the type of heart malformation and the degree of pathophysiological changes, and can be divided into three categories: radical surgery, palliative surgery, and heart transplantation.
(1) Radical surgery can return the anatomy of the heart to a normal human structure.
(2) Palliative surgery can only play a role in improving the symptoms but not the radical effect. It is mainly used for complex precordial diseases for which there is no radical cure, such as modified Glenn and Fontan surgery, or as a preparatory surgery to promote the growth and development of the original undeveloped structures to create conditions for radical surgery, such as body-lung bypass surgery.
(3) Heart transplantation is mainly used for terminal heart disease and complex precocious heart disease that cannot be treated with current surgical methods.
V. Prevention
1.Marriage and childbirth at the right age
Medical science has proved that the risk of fetal genetic abnormalities increases significantly in pregnant women over 35 years old. Therefore, it is best to have children before the age of 35. If this is not possible, then it is recommended that pregnant women of advanced age must undergo strict perinatal medical observation and health care.
2.Prepare to have a child before the psychological and physiological state should be well adjusted
If the mother-to-be has habits such as smoking and drinking alcohol, it is best to stop at least six months before pregnancy.
3.Strengthen the health care for pregnant women
Especially in the early pregnancy actively prevent rubella, influenza and other rubella viral diseases. Pregnant women should try to avoid taking drugs, if they must be used, it must be done under the guidance of a doctor.
4.Minimize exposure to radiation, electromagnetic radiation and other adverse environmental factors during pregnancy.
5.Avoid traveling to high altitude areas during pregnancy
Because it has been found that the incidence of congenital heart disease in high altitude areas is significantly higher than that in plain areas, which may be related to the lack of oxygen.