Overview
Remaining unclosed atrial foramina in the right and left ventricles of the heart
Usually asymptomatic in childhood; in adults, symptoms such as fatigue, shortness of breath after exertion, or palpitations may occur.
It is the result of the interaction between genetic and environmental factors.
Treatment options include interventional and surgical procedures
Definition
Atrial septal defect (ASD) is a congenital abnormality of the atrial septum with an unclosed foramen ovale between the right and left atria, and is a common congenital heart disease.
Epidemiology
Incidence rate
There is a lack of authoritative epidemiologic information on the incidence of atrial septal defect in China.
According to the statistics of some hospitals, the incidence rate of this disease among newborn infants is 1/1500.
Gender distribution
Females are more likely to develop atrial septal defect than males, with a male to female ratio of about 1:2.
Types of atrial septal defects
Atrial septal defects can be categorized into two types: primary foramen ovale and secondary foramen ovale.
Primary foramen ovale
The defect is in the lower part of the atrial septum, in front of and below the coronary sinus.
It is often combined with mitral valve dehiscence.
Secondary foramen ovale
More common than the primary foramen ovale.
The defect is located in the upper part of the atrial septum and can be subdivided into:
Central: the defect is located at the foramen ovale of the atrial septum.
Superior vena cava type: the defect is located on the septum at the entrance of the superior vena cava of the atrium.
Inferior vena cava type: the defect is located on the septum at the entrance of the inferior vena cava of the atria.
Mixed: Two or all three of the above conditions are present, resulting in a large defect in the atrial septum.
Secondary foraminal defects may be present alone or in conjunction with ventricular septal defects, patent ductus arteriosus, or other complex congenital cardiovascular malformations.
Etiology
Pathogenic factors
Atrial septal defects are the result of the interaction of genetic and environmental factors. The following factors may affect the development of the fetus, leading to atrial septal defects.
Genetic factors
Atrial septal defects run in families.
The mechanism of inheritance is not yet understood. Scientists believe that the disease is polygenic, with a heritability of about 57%.
Environmental factors
Infectious factors: virus infection in early pregnancy, such as rubella virus, coxsackie virus, etc.
Disease factors: pregnant women suffering from diabetes, phenylketonuria, hypercalcemia and other diseases, amniotic membrane lesions and so on.
Nutritional factors: Pregnant women suffer from malnutrition during pregnancy.
Physical factors: Pregnant women are exposed to more than the normal dose of radiation during pregnancy.
Other factors: intrauterine pressure on the fetus and amniotic membrane abnormalities.
Pathogenesis
The normal human heart is divided into left and right atria and left and right ventricles, which are separated from each other by a septal tissue called the atrial septum. Atrial septal defects occur when the septum does not close well during fetal heart development and an unclosed foramen ovale remains between the left and right atria.
As the child grows older, the left atrial pressure exceeds that of the right atrium, the left-to-right shunt increases, the pulmonary circulation load increases, and the corresponding symptoms appear.
Symptoms
Main Symptoms
Childhood
Atrial septal defects are usually asymptomatic in childhood.
In some cases, there may be developmental delay (height and weight are lower than those of healthy peers) and poor activity tolerance.
Adults
Dyspnea: usually after exercise or physical activity.
Shortness of breath: manifested as rapid breathing, uneven respiratory rate, etc.
Palpitations: i.e. increased heart rate, subjective feeling of panic.
Accompanying symptoms
Atrial septal defect is usually accompanied by symptoms such as weakness and cough.
Complications
Atrial septal defect can induce the following complications:
Arrhythmias: mainly right bundle branch conduction block. Self-experienced symptoms are usually rare, but some people present with blackouts (sudden blackness before the eyes), syncope, shortness of breath, palpitations, and cyanosis (cyanotic coloration of the skin and mucous membranes).
Eisenmenger Syndrome: The prolonged non-closure of the atrial septum creates pulmonary hypertension, resulting in higher pressure in the right atrium than in the left atrium, which in turn results in a right-to-left flow of blood, leading to a generalized hypoxia of the body due to the flow of unoxygenated blood through the entire body. Symptoms are mild to moderate cyanosis throughout the body.
Heart failure: Atrial septal defects can be complicated by right heart failure. The following manifestations may be seen.
Jugular vein varicose, which is known as “cyanosis”.
Edema of the feet, ankles, and tibialis anterior appears first, and gradually spreads upward to the whole body.
Increased heart rate.
Cyanosis.
Pain in the right upper abdomen.
Consultation
Department of Medicine
Cardiovascular Medicine
Routine physical examination reveals atrial septal defect, or symptoms such as fatigue, shortness of breath after exertion or palpitations, it is recommended to consult the Department of Cardiovascular Medicine promptly.
Emergency Department
Sudden severe chest pain, dyspnea, etc., it is recommended to go to the Emergency Department immediately.
In the event of loss of consciousness, respiratory and cardiac arrest, immediately call the 120 emergency number and perform cardiopulmonary resuscitation (CPR) on the patient at the same time.
Preparation
Preparing for your visit: registration, information preparation, common problems
Tips for medical treatment
Atrial septal defects in young children are usually characterized by lower height and weight than their healthy peers and inactivity. Parents should take their children for regular medical checkups and pay attention to whether their children’s behavior is normal or not.
Preparation List
Symptom list
Particular attention should be paid to the time of onset of symptoms, special manifestations, etc.
What are the main symptoms? Is there any discomfort such as dyspnea, shortness of breath, palpitations, or fatigue?
How long have they lasted? Do these symptoms resolve on their own? Are there any mitigating factors?
Is it aggravated by exercise? Any other aggravating factors?
Have you experienced similar symptoms in the past? How often?
Medical History Checklist
Has anyone else in the family had congenital heart disease?
Did the mother have any illnesses during pregnancy and what was her nutritional status during pregnancy?
Are there any other medical conditions?
What treatments were received and what were the results?
Checklist
Test results from the last six months, which can be brought to the doctor’s office
Blood tests
Blood biochemistry
Echocardiogram
Chest X-ray
Catheterization
Electrocardiogram and 24-hour ECG
Diagnosis
Disease Diagnosis
Diagnosis is made by relevant medical history, clinical manifestations (signs and symptoms), ECG, imaging, and catheterization findings.
Medical history
There is a family history of the disease.
History of infectious diseases, radiation exposure, malnutrition, diabetes mellitus, hypercalcemia, etc. in the mother of the newborn during pregnancy.
Clinical manifestations
Symptoms: symptoms such as fatigue, shortness of breath after exertion or palpitations.
Signs: A systolic ejective heart murmur may be present on auscultation in the anterior chest region, and a hyperactive and fixed splitting of the second heart sound may also be heard.
Electrocardiogram
The electrocardiogram is one of the main tests for diagnosing heart disease. Therefore, an electrocardiogram should be performed whether or not it is accompanied by symptoms.
Atrial septal defect ECG shows right bundle branch conduction block and right deviation of electrical axis.
Echocardiography
Echocardiography can clearly observe the structure of the heart, determine the presence of underlying heart disease, and detect abnormal blood shunting, and is currently the main examination for diagnosing atrial septal defect.
Transesophageal echocardiography (TOE or TEE) may be used when conditions permit. The doctor will place an ultrasound probe into the esophagus to explore the deep structures of the heart from the back of the heart forward at close range, thus avoiding interference from the chest wall, lung air, etc., and therefore providing a clearer image. It is mainly used for people with sternal deformities or poor sound transmission conditions.
Chest X-ray
The right atrium and right ventricle can be found to be enlarged in size, the so-called “pear-shaped heart”. In addition, this examination may also reveal a compensatory increase in pulmonary vascularization, resulting in the “hilar chorea sign”, which is a distinctive pulsation of the pulmonary arteries and hilar vessels that appears on x-ray.
Catheterization
A catheterization can be used to visualize atrial septal defects, as well as to check the function of the heart valves and to measure the pulmonary wedge pressure.
Catheterization is an invasive test and is generally not used to diagnose atrial septal defects, but is often used when the defect is small enough to be treated with occlusion.
Differential diagnosis
Idiopathic pulmonary hypertension
Similarities: Dyspnea, fatigue and other symptoms. Complications such as right heart failure and lung infection can be induced.
Differences: idiopathic pulmonary hypertension usually does not have an atrial septal defect and does not present with symptoms such as cyanosis. It can be differentiated by echocardiography and chest X-ray.
Ectopic drainage of pulmonary vein
Similarity: Congenital heart disease caused by structural anomalies. Symptoms such as dyspnea, cyanosis, developmental delay, palpitations, shortness of breath, and fatigue can occur, and both can induce right heart failure.
Differences: Ectopic pulmonary venous drainage is a congenital cardiovascular ectasia in which the pulmonary veins fail to connect directly to the left atrium and instead connect to the right atrium or the body venous system, which is different from the pathogenesis of atrial septal defects. It can be differentiated by echocardiography.
Atrial fibrillation
Similarity: symptoms such as panic, dizziness, or even syncope and dyspnea.
Difference: Atrial fibrillation has an atrial frequency of 300-600 beats/minute and changes irregularly. It can be differentiated by electrocardiogram.
Treatment
Aim of treatment: to repair the defect, relieve the symptoms and avoid serious complications.
Treatment methods: interventional therapy, surgical treatment, etc.
Interventional therapy
The commonly used method is atrial septal defect occlusion, which is carried out under the guidance and monitoring of imaging equipment, and is able to accurately and directly reach the diseased area and occlude the defect.
Compared with traditional surgical treatment, it has the advantages of accuracy, safety, simplicity, less trauma, less pain, fewer surgical complications, and quicker postoperative recovery.
Indications
Age above 3 years old.
The diameter of the defect is 5-36 millimeters.
Increased volume load on the right heart.
The edge of the stump around the defect is more than 5 millimeters, and the mitral stump is more than 7 millimeters.
Surgical treatment
There are 2 types of traditional open heart surgery and thoracoscopic surgery.
The traditional surgical treatment is to open the chest and use a patch to repair the defect; open surgery is traumatizing, with slow postoperative recovery and a high complication rate, and is now used less frequently and has been gradually replaced by thoracoscopic surgery.
Traditional surgery requires extracorporeal circulation using hypothermic anesthesia and an artificial heart-lung device, which temporarily interrupts blood flow to the heart, and then directly repairs the defect.
Indications: Surgery is required if the defect in the atrial septum is large or combined with other cardiac malformations that are not amenable to interventional therapy.
Contraindications: Surgery cannot be performed in the presence of Eisenmenger’s syndrome.
Complications: Complications after conventional open heart surgery are atrioventricular block and air embolism.
Prognosis
Cure
Smaller atrial septal defects may close with development within the first year of life and are somewhat self-healing.
Larger atrial septal defects do not heal spontaneously and require surgery.
Large defects with complications or other malformations are more difficult to treat.
Hazards
Impact on growth and development: If the atrial septal defect is large, it will cause feeding difficulties and developmental delay, affecting the normal growth and development of the child.
Impact on normal life: Atrial septal defects can cause breathing difficulties and reduced mobility, affecting normal life.
Impact on mental health: some patients may have fear, anxiety and other negative emotions because of the disease, and children may also have low self-esteem, which affects their mental health.
Complications: It may cause arrhythmia, Eisenmenger’s syndrome and right heart failure.
Daily life
Daily life
Dietary regulation
Low salt and low fat diet.
You can eat more green vegetables, fresh fruits, foods high in calcium and potassium.
Consume sufficient amount of high quality protein and eat less food with high cholesterol.
It is not advisable to be overly satiated.
Nursing infants should ensure the amount of breastfeeding and add complementary food in time.
Lifestyle Habits
Ensure reasonable sleep time.
Avoid excessive stress and keep tension.
Prevent infection, such as in the season of high incidence of upper respiratory tract infectious diseases, should wear a mask when going out.
Atrial septal defects generally do not require restriction of exercise. Therefore, proper exercise and physical fitness should be practiced.
Adults should quit smoking and drinking.
Mood adjustment
Positively adjust the bad mood and keep a good state of mind.
Follow-up
Follow your doctor’s instructions for regular follow-up.
If any discomfort occurs on a daily basis, it is recommended to consult a doctor promptly.
Prevention
Avoid random use of medication and exposure to radiation during pregnancy.
Pregnant women with primary diseases such as diabetes and hypercalcemia need to be actively treated.
A balanced diet is needed during pregnancy, avoiding picky eating and dieting.
During the first 3 months of pregnancy, avoid going to crowded places with poor air circulation, and go out for protection, such as wearing a mask.
Those with family history of congenital heart disease are recommended to have regular medical checkups, especially cardiac ultrasound.