Left heart dysplasia

Introduction to left heart dysplasia Left ventricular dysplasia is a rare and complicated congenital cardiovascular malformation with an incidence of about 1 to 27/100,000, accounting for about 1.4% of congenital cardiovascular malformations. The common point of this type of malformation is that the left heart circulation has stenosis or atresia in a certain part, and the left atrium, pulmonary veins and pulmonary artery are dilated and the pressure is increased, so the blood flow in the right ventricle is increased, and the arterial catheter must be accompanied to survive. In 1952, Lev called the left ventricular dysplasia and congenital cardiovascular malformation of the right hemifacial hypertrophy as the left ventricular dysplasia syndrome. In 1958, Noonan and Nadas were referred to as left ventricular dysplasia syndrome for left ventricular access obstruction and dysplasia. basic knowledge The proportion of sickness: 0.01% - 0.02% Susceptible people: no special people Mode of infection: non-infectious Complications: hypoglycemia shock

Cause of left ventricular dysplasia

Causes:

Genetic factors (30%):

Many chromosomal abnormalities and genetic syndromes are associated with cardiac dysplasia, and 25-30% of the fetuses we found to have cardiac dysplasia before birth are chromosomal abnormalities.

Environmental factors (30%):

Exposure to certain substances or drugs during pregnancy, such as alcohol, lithium, vitamin A, anticonvulsants, reaction stop, steroids, amphetamines, anesthetics and oral contraceptives or large doses of radiation, etc., the chance of fetal heart dysplasia is about 1: 50.

Biological factors (20%):

Intrauterine infection with rubella virus, cytomegalovirus, coxsackie virus may cause fetal heart malformation.

Immunity factor (15%):

Pregnant women with diabetes have five times the chance of fetal heart malformation.

Pathogenesis:

The main pathological features of this disease are: 1 aortic valve atresia or severe stenosis and ascending aorta dysplasia, about 35 to 80% of cases with aortic coarctation. 2 mitral atresia or dysplasia. 3 left ventricular is not developed. 4 The right half of the heart hypertrophy showed an increase in the right atrium and right ventricle, especially the abnormal enlargement of the common pulmonary artery. 5 There are large arterial catheters, atrial septal defect or patent foramen ovale.

Classification: UrbaN and ScHwarzenberg divide the intrinsic into five categories:

1. Aortic atresia:

a. with mitral dysplasia or stenosis; b. with mitral atresia.

2. Mitral valve atresia.

3, mitral stenosis:

a. normal aortic orifice; b. with aortic stenosis.

4, aortic arch dysplasia.

5, the aortic arch is locked or disconnected.

Noonan is divided into two categories:

a. aortic atresia or severe stenosis; b. mitral atresia.

Hemodynamics: In the case of left ventricular dysplasia, the right atrium receives both the blood from the superior and inferior vena cava and the blood from the left atrium through the atrial septal defect. Therefore, the body and pulmonary venous blood were pumped into the common pulmonary artery and left and right pulmonary artery by the right ventricle after mixing in the right atrium, and antegrade into the descending aorta through the thick arterial catheter, and retrograde perfusion of the ascending aorta and coronary artery. Atrial septal defect and bifurcation of the arterial catheter are prerequisites for the completion of the body and pulmonary circulation in children with left ventricular dysplasia. Moreover, the partial flow of the atrial septal defect and the arterial oxygen saturation are proportional to the size of the atrial septal defect. After birth, due to the significant decrease in pulmonary circulation resistance, pulmonary blood flow increased, and often accompanied by aortic coarctation and arterial catheter closure, so the body circulation resistance is higher. The ratio of body and lung blood flow is dysfunctional, resulting in pulmonary congestion, pulmonary edema and congestive heart failure, and insufficient blood perfusion of organs, hypoxemia and acidosis, and eventually death.

Left heart dysplasia prevention

1. Age-appropriate marriage

Medicine has shown that the risk of fetal genetic abnormalities is significantly increased in pregnant women over the age of 35. Therefore, it is best to give birth before the age of 35. If this is not possible, it is recommended that older pregnant women must undergo strict perinatal medical observation and care.

2. Prepare to adjust the psychological and physiological state before preparing the child.

If the expectant mother has the habit of smoking, drinking, etc., it is best to stop at least half a year before pregnancy.

3. Strengthen health care for pregnant women

Especially in the early pregnancy, actively prevent rubella and flu such as rubella. Pregnant women should try to avoid taking drugs. If they have to use them, they must be under the guidance of a doctor.

4. Minimize exposure to adverse environmental factors such as radiation and electromagnetic radiation during pregnancy.

5. Avoid going to high altitude areas during pregnancy

Because the incidence of congenital heart disease at high altitudes has been found to be significantly higher than in plain areas, it may be related to hypoxia.

Left heart dysplasia complications Complications hypoglycemia shock

The disease is often accompanied by acidosis, hypoglycemia, hypoxemia and shock. If the atrial septal defect has a large flow rate, the purpura may not be obvious, and the hypoxemia is mild. About 90% of the children are not diagnosed in time. Treatment often dies within 1 month of birth.

Left ventricular dysplasia common symptoms, acute urgency, neonatal cyanosis, dyspnea, hypoxemia, neonatal cyanosis, shortness of breath, shock

The child can be a normal term infant, but progressive purpura, shortness of breath or difficulty breathing and heart failure can occur several hours after birth. Cardiac auscultation has no specific murmur. The second sound of the pulmonary valve area is hyperthyroidism and single. The pulse is weak. With acidosis, hypoglycemia, hypoxemia and shock. If the volume of atrial septal defect is large, purpura may not be obvious, and hypoxemia is mild. About 90% of children often die within 1 month after birth if they are not diagnosed and treated in time.

Left heart dysplasia check

Chest X-ray: showing the right atrium, the right ventricle is enlarged, the heart shadow is spherical, the lung is congested, and the pulmonary edema is manifested.

Electrocardiogram examination: p wave high tip, right axis right and right ventricular hypertrophy.

Echocardiography: Two-dimensional imaging showed a large right atrium, right ventricle, and small left wall ventricular wall thickness, mitral dysplasia, ascending aorta and small bow.

Right heart catheterization: can show atrial horizontal shunt and confirm the presence of arterial catheter, but when the systemic pressure and oxygen saturation are close to the pulmonary circulation, atrial shunt can not be measured.

Cardiovascular angiography: pulmonary angiography can be found in the aorta through the arterial catheter and can show aortic coarctation. Retrograde aortic angiography shows ascending aorta and arch dysplasia or aortic coarctation or disconnection. Left atrial angiography can be understood Mitral valve development.

Diagnosis and diagnosis of left ventricular dysplasia

diagnosis

Can be diagnosed based on clinical performance and laboratory tests.

Differential diagnosis

1, aortic valve atresia

The left ventricular diastolic phase of patients with valvular insufficiency undergoes left atrial blood while additionally receiving blood from the aorta, resulting in a gradual increase in left ventricular end-diastolic volume, with the left ventricle compensating with myofibrils. Produce eccentric left ventricular hypertrophy, increase left ventricular compliance, gradually adapt to chronic left ventricular chronic volume overload, ensure - left ventricular end-diastolic volume increases and left ventricular end-diastolic pressure in the normal range, this myocardial compensation mechanism can be maintained For a long time, the patient is asymptomatic, but as the disease progresses, the ventricular wall hypertrophy is aggravated. The left heart is mainly in the subendocardial area. With left ventricular systolic and diastolic dysfunction, symptoms appear and the left ventricular function is fast. Reducing is irreversible; therefore, such patients often fail to see a doctor for a long period of time due to myocardial compensatory mechanisms because of no symptoms. Once symptoms appear, they quickly cause irreversible changes in left ventricular function, even Surgery, the prognosis is also relatively poor.

2, mitral atresia

In patients with coronary atherosclerotic heart disease, about 3% of patients undergo mitral regurgitation by cardiac catheterization. The mitral regurgitation caused by coronary heart disease can be caused by acute or chronic papillary muscle ischemia. In myocardial infarction, papillary muscle can cause Acute ischemic necrosis and complete rupture within a few hours. Although there is no abnormal lesion in the chordae and valve leaflets, the mitral valve leaflets in the corresponding site lose the function of opening and closing, and the mitral valve closure is severe in the early stage after the infarction. Incomplete, in the case of acute myocardial infarction, the sudden death of the mitral regurgitation due to rupture of the papillary muscle accounted for about 0.4 to 5%. In some patients, myocardial infarction caused avascular necrosis of the papillary muscle, but did not completely break immediately. Or due to long-term ischemia, necrotic myocardial tissue is gradually replaced by fibrous tissue, papillary muscles become thinner, elongation, contraction function is weakened or lost, mitral regurgitation is present more than 2 months after myocardial embolization, early lesions Symptoms can appear intermittently, and then the degree of mitral regurgitation gradually worsens, the ventricle and left atrium expand significantly, cardiac function declines and presents heart failure.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.