A congenital heart defect ( CHD ), also known as congenital heart defects or congenital heart disease , is a problem in the structure of the heart that is present at birth. Signs and symptoms depend on the specific type of problem. Symptoms may vary from non-life-threatening. Currently they may include rapid breathing, bluish skin, weight gain, and feel tired. It does not cause chest pain. Most congenital heart problems do not occur in other diseases. Complications that can occur due to heart defects include heart failure.
The cause of congenital heart defects is often unknown. Certain cases may be caused by infections during pregnancy such as rubella, use of drugs or certain drugs such as alcohol or tobacco, close parenthood, or malnutrition or maternal obesity. Having a parent with congenital heart defects is also a risk factor. A number of genetic conditions are associated with heart defects including Down syndrome, Turner syndrome, and Marfan syndrome. Congenital heart abnormalities are divided into two main groups: cyanotic heart defects and non-cyanotic heart defects, depending on whether the child has the potential to turn bluish in color. The problem may involve the inner wall of the heart, the heart valve, or the large blood vessels leading to and from the heart.
Congenital heart abnormalities can be partially prevented through rubella vaccination, addition of iodine to salt, and addition of folic acid to certain food products. Some defects do not require maintenance. Others may be effectively treated with catheter-based procedures or cardiac surgery. Sometimes a number of surgeries may be needed, or a heart transplant may be required. With proper care, the results are generally good, even with complicated problems.
Heart defects are the most common birth defects. By 2015 they are present in 48.9 million people worldwide. They affect between 4 and 75 per 1,000 live births depending on how they are diagnosed. Around 6 to 19 per 1,000 causes moderate to severe problems. Congenital heart abnormalities are the leading cause of death related birth defects. By 2015 they produced 303,300 deaths down from 366,000 deaths in 1990.
Video Congenital heart defect
Signs and symptoms
Signs and symptoms related to the type and severity of heart defects. Symptoms are often present early in life, but it is possible for some CHD to be undetectable throughout life. Some children have no signs while others may show shortness of breath, cyanosis, fainting, heart grumbling, lack of limbs and muscles, poor eating or growth, or respiratory infections. Congenital heart abnormalities cause abnormal heart structures that produce a certain sound production called heart snoring. This can sometimes be detected by auscultation; However, not all heart murmurs are caused by congenital heart defects.
Related symptoms
Congenital heart abnormalities are associated with an increased incidence of several other symptoms, together called the VACTERL association:
- V - Vertebral anomalies
- A - anal Atresia
- C - Cardiovascular anomalies
- T - Fistula trakeoesofagus
- E - esophageal atresia
- R - Kidney (Kidney) and/or radial anomalies
- L - Stuttering
The ventricular septal defect (VSD), atrial septal defect, and tetralogy of Fallot are the most common congenital heart abnormalities seen in the VACTERL association. Less common defects in associations are the truncus arteriosus and transposition of the large arteries.
Maps Congenital heart defect
Cause
The cause of congenital heart disease may be genetic, environmental, or a combination of both.
Genetic
Most of the known causes of congenital heart disease are sporadic genetic changes, either focal mutations or removal or addition of DNA segments. Large chromosomal abnormalities such as trisomy 21, 13, and 18 cause about 5-8% of CHD cases, with trisomy 21 being the most common genetic cause. Small chromosomal abnormalities also often cause congenital heart disease, and examples include long-term chromosomal microdeletion 22 (22q11, DiGeorge syndrome), long arm chromosome 1 (1q21), short arm chromosome 8 (8p23) and many other less recurrent genomic areas, such as which is shown by high-resolution wide-genome screening (Array comparative genomic hybridization).
The genes that regulate the order of complex development have only been partially explained. Some genes are associated with specific defects. A number of genes have been linked to cardiac manifestations. Mutation of heart muscle protein, myosin-heavy chain (MYH6) is associated with atrial septal defect. Some of the proteins that interact with MYH6 are also associated with heart damage. GATA4 transcription factor forms a complex with TBX5 that interacts with MYH6. Another factor, the homeobox (developmental) gene, NKX2-5 also interacts with MYH6. Mutations of all these proteins are associated with atrial and ventricular septal defects; In addition, NKX2-5 is associated with defects in cardiac electrical conduction and TBX5 associated with Holt-Oram syndrome that includes electrical conduction defects and upper limb abnormalities. Other T-box genes, TBX1, are involved in the velo-cardio-facial syndrome DiGeorge syndrome, the most common deletion that has widespread symptoms including cardiac duct defects including tetralogy of Fallot.
Molecular path
Notch signal pathways, regulatory mechanisms for cell growth and differentiation, play a broad role in some aspects of cardiac development. The notch element is involved in the determination of the right and left sides of the body plan, so that the folds in the direction of the heart tube can be affected. Marking the notch engages in the beginning of the formation of the endocard bearing and continues to activate as it progresses to the septa and valve. It is also involved in the development of ventricular walls and outlet connections to large blood vessels. Mutations in the gene for one of the notch ligands, Jagged1 , are identified in most cases examined by arteriohepatic dysplasia (Alagille syndrome), characterized by large vessel defects (pulmonary artery stenosis), heart. (tetralogy of Fallot in 13% of cases), liver, eyes, face, and bones. Although less than 1% of all cases, where no defects are found in the Jagged1 genes, defects are found in the Notch2 genes. In 10% of cases, no mutations were found in the gene. For other members of the gene family, mutations in the Notch1 gene are related to a bicuspid aortic valve, a valve with two leaflets, not three. Notch1 is also associated with aortic valve calcification, the third most common cause of heart disease in adults.
Mutations from cell regulatory mechanisms, Ras/MAPK pathways are responsible for various syndromes, including Noonan syndrome, LEOPARD syndrome, Costello syndrome and cardiofaciocutaneous syndrome in which there is cardiac involvement. While the conditions listed are known genetic causes, there are likely many more subtle genes. It is known that the risk of congenital heart defects is higher when there is a close relative to one.
Environment
Known environmental factors include certain infections during pregnancy such as Rubella, drugs (alcohol, hydantoin, lithium and thalidomide) and maternal disease (diabetes mellitus, phenylketonuria, and systemic lupus erythematosus).
Being overweight or obese increases the risk of congenital heart disease. In addition, when maternal obesity increases, the risk of heart defects also increases. Different physiological mechanisms have not been identified to explain the relationship between maternal obesity and CHD, but folic acid deficiency and pre-pregnant diabetes have been implicated in several studies.
Mechanism
There is a complex sequence of events that produce a well-formed heart at birth and disruption of any part can cause defects. The regular time of cell growth, cell migration, and programmed cell death ("apoptosis") has been studied extensively and the genes that control the process are being described. Around the 15th day of development, the cells that will become the heart are in two horseshoe-shaped ribbons of the intermediate mesoderm layer, and some cells migrate from some of the outer layer (ectoderm), the neural symbol, which is the source of the various cells found in whole body. On the 19th day of development, a pair of vascular elements, "endocardial tubes", are formed. The tubes coalesce when the cells in between then undergo programmed death and cells from the first heart field migrate to the tube, and form the ring of heart cells (myocytes) around it on the 21st day. On day 22, the heart begins to beat and at noon. 24, blood is circulating.
On day 22, the circulatory system is bilaterally symmetrical with ships paired on each side and the heart consists of a simple tube located at the centerline of body order. The parts that will become the atria and will be located closest to the head are the most distant from the head. From day 23 to 28, the folds of the heart tube and the bend, with the ventricle of the future moving to the left of the center (the location of the peak of the heart) and the atria moving toward the head.
On the 28th day, the tissue area inside the heart tube begins to expand inside; after about two weeks, this expansion, the "septum primum" membrane and the muscular "endocard pillow", combine to form four chambers of the heart. Failure to blend properly will result in defects that allow blood to leak between rooms. Once this happens, cells that have migrated from the neural crest begin to divide the bulbus cordis, the main flow channel divided into two by the growth of the spiral septum, into large blood vessels - ascending aortic segments and pulmonary trunk.. If the separation is incomplete, the result is a "persistent trunk artery". The vessels may be reversed ("transposition of large blood vessels"). Two parts of the split tract should migrate to the correct position above the right ventricle. Failure can cause some blood to flow into the wrong vessel ( for example overwrites the aorta). The four-chambered heart and large vessels have the features required for fetal growth. The lungs are not expanded and can not accommodate full circulation volume. There are two structures to clog the bloodstream from the lungs. The cells in the dead primum septum create holes while the muscle cells, "septum secundum", grow along the right atrium of the primum septum, except for one region, leaving a gap where blood can pass from the proper meaning into the left atrium, foramen ovale. A small vessel, ductus arteriosus allows blood from the pulmonary artery to pass into the aorta.
Change at birth
The ductus arteriosus remains open due to circulatory factors including prostaglandins. The foramen ovale remains open due to blood flow from the right atrium to the left atrium. As the lungs expand, blood flows easily through the lungs and the membranamen part of the foramen ovale (the primum septum) flaps over the muscle (septum secundum). If the closure is incomplete, the result is a patent foramen ovale. Both flaps can melt, but many adults have a foramen ovale that remains closed only because of the difference in pressure between the atria.
Theory
Rokitansky (1875) describes congenital heart defects as a breakdown in heart development at different stages of ontogenesis. Spitzer (1923) treats them as returning to one of the phylogenetic stages. Krimsky (1963), synthesizing two earlier points of view, considers congenital cardiovascular disease to cease development at certain ontogenesis stages, according to this or that phylogenesis stage. Therefore, these theories can explain the types of feminine and neutral defects only.
Diagnosis
Many congenital heart defects can be diagnosed before birth with fetal echocardiography. This is a test that can be done during the second trimester of pregnancy, when the woman is about 18-24 weeks pregnant. This can be a transvaginal ultrasound of the abdomen or ultrasound.
If the baby is born with cyanotic heart disease, the diagnosis is usually made soon after birth because of their skin blue color (called cyanosis).
If the baby is born with a septal defect or an obstruction defect, often their symptoms are only seen after a few months or sometimes even after many years.
Classification
A number of classification systems exist for congenital heart defects. In 2000, the International Congenital Heart Surgery Nomenclature was developed to provide a generic classification system. Hypoplasia
Hypoplasia can affect the heart, usually resulting in backwardness of the right ventricle or left ventricle. This causes only one side of the heart that is able to pump blood to the body and lungs effectively. Cardiac hypoplasia is rare but is the most serious form of CHD. This is called the left hypoplastic heart syndrome when it affects the left side of the heart and the right hypoplastic heart syndrome when it affects the right side of the heart. In both cases, the presence of patent ductus arteriosus (and, when hypoplasia affects the right side of the heart, the foramen ovale) is essential for the baby's ability to survive until emergency heart surgery can be performed, because without this path blood can not circulate into the body -power, depending on which side of the heart is broken). Cardiac hypoplasia is generally a cyanotic heart defect.
Disabled obstruction
Obstruction defects occur when the heart valves, arteries, or veins are abnormal or clogged. Common defects include pulmonary stenosis, aortic stenosis, and aortic coarctation, with other types such as bikuspid aortic valve stenosis and subaortic stenosis relatively rare. Any constriction or blockage can cause heart or hypertension enlargement.
Septum defect
The septum is the network wall separating the left heart from the right heart. Defects in the interatrial septum or interventricular septum allow blood to flow from the right side of the heart to the left, reducing the efficiency of the heart. The ventricular septal defect is collectively the most common type of CHD, although about 30% of adults have an atrial septal defect type called the foramen ovale probe.
Cyanotic defects
Cyanotic heart defects are so called because they cause cyanosis, a grayish discoloration of the skin due to lack of oxygen in the body. Such defects include persistent tract arteries, total anomalous pulmonary vein connections, Fallot tetralogy, large vessel transposition, and tricuspid atresia.
Disabled
- Aortic stenosis
- Atrial septal defect (ASD)
- Atrioventricular septal defect (AVSD)
- Bicuspid aortic valve
- Cardiomyopathy
- Complete heart block (CHB)
- Dextrocardia
- Double left ventricle (DILV)
- Double right ventricle outlet (DORV)
- Ebstein Anomalies
- Hipoplastic left heart syndrome (HLHS)
- Right hypoplastic heart syndrome (HRHS)
- Mitral stenosis
- Persistent trunkus arteriosus
- Pulmonary Atresia
- Pulmonary stenosis
- Rhabdomyomas (Heart Tumors)
- Transposition of large ships
- dextro-Transposition of large arteries (d-TGA)
- levo-Transposition of large arteries (l-TGA)
- Tricuspid atresia
- Ventricular septal defect (VSD)
- Wolff-Parkinson-White (WPW) syndrome
conditions affect the large blood vessels or other blood vessels near the heart, but not the heart itself, but are often classified as congenital heart defects.
- Coarcation of the aorta (CoA)
- Double aortic artery, deviant subclavian artery, and other malformations of large arteries
- Aortic disorder is discontinued (IAA)
- Patent ductus arteriosus (PDA)
- Skimitar syndrome (SS)
- Partial pulmonary vein anomaly (PAPVC) connection
- Total anomalous pulmonary vein connections (TAPVC)
Some constellations of some defects are commonly found together.
- Tetralogy of Fallot (ToF)
- Pentalogy of Cantrell
- Shone's syndrome/Shone's complex/Shone's anomaly
Treatment
Sometimes CHD improves without treatment. Other defects are so small that they do not require any treatment. Most of the time the CHD is serious and requires surgery and/or medication. Drugs include diuretics, which help the body in removing water, salt, and digoxin to strengthen heart contractions. This slows the heart rate and removes fluid from the tissues. Some defects require a surgical procedure to restore normal circulation and in some cases, multiple operations are required.
Interventional cardiology now offers minimally invasive alternative patients for surgery for some patients. The Melody Transcatheter Pulmonary Valve (TPV), approved in Europe in 2006 and in the US in 2010 under the Humane Device Liberation (HDE), is designed to treat patients with congenital heart disease with dysfunctional channels in their right ventricular outflow (RVOT). RVOT is the relationship between the heart and the lungs; once the blood reaches the lungs, it is enriched with oxygen before it is pumped throughout the body. Transcacheter pulmonary valve technology provides a less invasive way to prolong the life of a failed RVOT channel and is designed to allow doctors to provide a replacement pulmonary valve through a catheter through a patient's bloodstream.
Most patients require special lifetime cardiac care, first with a pediatric cardiologist and then with an adult congenital heart expert. There are more than 1.8 million adults living with congenital heart defects.
Epidemiology
Heart defects are one of the most common birth defects, occurring in 1% of live births (2-3% including bicuspid aortic valves). In 2013, 34.3 million people have CHD. In 2010, they produced 223,000 deaths, down from 278,000 deaths in 1990.
For congenital heart defects that arise without a family history (de novo), the risk of recurrence in offspring is 3-5%. This risk is higher in left ventricular outflow obstruction, heterotaxy, and atrioventricular septal defect.
Terminology
Congenital heart abnormalities are known by a number of names including congenital heart anomalies, congenital heart disease, heart defects, and congenital cardiovascular malformations.
See also
- Congenital Heart Surgeon
- Caring for people with CHD
References
External links
- Congenital cardiac abnormalities in Curlie (based on DMOZ)
- Cove Point Cardiac Dead Sea Site - comprehensive patient education, including operational animation and intervention
- Congenital heart disease information for the elderly.
Source of the article : Wikipedia
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