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In mild cases, children may show no signs or symptoms at first and their condition may not be diagnosed until later in life. Some children born with coarctation of the aorta have other heart defects too, such as aortic stenosis, ventricular septal defect, patent ductus arteriosus or mitral valve abnormalities.
Coarctation is about twice as common in boys as it is in girls. It is common in girls who have Turner syndrome.
Symptoms may be absent with mild narrowings (coarctation). When present, they include: difficulty breathing, poor appetite or trouble feeding, failure to thrive. Later on, children may develop symptoms related to problems with blood flow and an enlarged heart. They may experience dizziness or shortness of breath, faint or near-fainting episodes, chest pain, abnormal tiredness or fatigue, headaches, or nosebleeds. They have cold legs and feet or have pain in their legs with exercise (intermittent claudication).
In more severe cases, where severe coarctations, babies may develop serious problems soon after birth because not enough blood can get through the aorta to the rest of their body.
Arterial hypertension in the arms with low blood pressure in the lower extremities is classic. In the lower extremities, weak pulses in the femoral arteries and arteries of the feet are found.
The coarctation typically occurs after the left subclavian artery. However, if situated before it, blood flow to the left arm is compromised and asynchronous or radial pulses of different "strength" may be detected (normal on the right arm, weak or delayed on the left), termed "radio-radial delay". In these cases, a difference between the normal radial pulse in the right arm and the delayed femoral pulse in the legs (either side) may be apparent, whilst no such delay would be appreciated with palpation of both delayed left arm and either femoral pulses. On the other hand, a coarctation occurring after the left subclavian artery will produce synchronous radial pulses, but "radio-femoral delay" will be present under palpation in either arm (both arm pulses are normal compared to the delayed leg pulses).
It can be diagnosed with an echocardiogram. Patients will have a loss of appetite, turn pale, may feel cold in the lower half of the body due to not enough blood flow.
Symptoms are caused by vascular compression of the airway, esophagus or both. Presentation is often within the first month (neonatal period) and usually within the first 6 months of life. Starting at birth an inspiratory and expiratory stridor (high pitch noise from turbulent airflow in trachea) may be present often in combination with an expiratory wheeze. The severity of the stridor may depend on the patient’s body position. It can be worse when the baby is lying on his back rather than its side. Sometimes the stridor can be relieved by extending the neck (lifting the chin up). Parents may notice that the baby’s cry is hoarse and the breathing noisy. Frequently a persistent cough is present. When the airway obstruction is significant there may be episodes of severe cyanosis (“blue baby”) that can lead to unconsciousness. Recurrent respiratory infections are common and secondary pulmonary secretions can further increase the airway obstruction.
Secondary to compression of the esophagus babies often feed poorly. They may have difficulties in swallowing liquids with choking or regurgitating and increased respiratory obstruction during feeding. Older patients might refuse to take solid food, although most infants with severe symptoms nowadays are operated upon before they are offered solid food.
Occasionally patients with double aortic arches present late (during later childhood or adulthood). Symptoms may mimic asthma.
A right ventricular outflow tract obstruction (RVOTO) may be due to a defect in the pulmonic valve, the supravalvar region, the infundibulum, or the pulmonary artery.
- Pulmonary atresia
- Pulmonary valve stenosis
- Hypoplastic right heart syndrome
- Tetralogy of Fallot
A left ventricular outflow tract obstruction (LVOTO) may be due to a defect in the aortic valve, or a defect located at the subvalvar or supravalvar level.
- Aortic valve stenosis
- Supravalvar aortic stenosis
- Coarctation of the aorta
- Hypoplastic left heart syndrome
There are three types of aortic coarctations:
1. Preductal coarctation: The narrowing is proximal to the ductus arteriosus. Blood flow to the aorta that is distal to the narrowing is dependent on the ductus arteriosus; therefore severe coarctation can be life-threatening. Preductal coarctation results when an intracardiac anomaly during fetal life decreases blood flow through the left side of the heart, leading to hypoplastic development of the aorta. This is the type seen in approximately 5% of infants with Turner syndrome.
2. Ductal coarctation: The narrowing occurs at the insertion of the ductus arteriosus. This kind usually appears when the ductus arteriosus closes.
3. Postductal coarctation: The narrowing is distal to the insertion of the ductus arteriosus. Even with an open ductus arteriosus, blood flow to the lower body can be impaired. This type is most common in adults. It is associated with notching of the ribs (because of collateral circulation), hypertension in the upper extremities, and weak pulses in the lower extremities. Postductal coarctation is most likely the result of the extension of a muscular artery (ductus arteriosus) into an elastic artery (aorta) during fetal life, where the contraction and fibrosis of the ductus arteriosus upon birth subsequently narrows the aortic lumen.
Aortic coarctation and aortic stenosis are both forms of aortic narrowing. In terms of word root meanings, the names are not different, but a conventional distinction in their usage allows differentiation of clinical aspects. This spectrum is dichotomized by the idea that aortic coarctation occurs in the aortic arch, at or near the ductus arteriosis, whereas aortic stenosis occurs in the aortic root, at or near the aortic valve. This naturally could present the question of the dividing line between a postvalvular stenosis and a preductal coarctation; nonetheless, the dichotomy has practical use, as most defects are either one or the other.
Double aortic arch (DAA) is a relatively rare congenital cardiovascular malformation. DAA is an of the aortic arch in which two aortic arches form a complete vascular ring that can compress the trachea and/or esophagus. Most commonly there is a larger (dominant) right arch behind and a smaller (hypoplastic) left aortic arch in front of the trachea/esophagus. The two arches join to form the descending aorta which is usually on the left side (but may be right-sided or in the midline). In some cases the end of the smaller left aortic arch closes (left atretic arch) and the vascular tissue becomes a fibrous cord. Although in these cases a complete ring of two patent aortic arches is not present, the term ‘vascular ring’ is the accepted generic term even in these anomalies.
The symptoms are related to the compression of the trachea, esophagus or both by the complete vascular ring. Diagnosis can often be suspected or made by chest x-ray, barium esophagram, or echocardiography. Computed tomography (CT) or magnetic resonance imaging (MRI) show the relationship of the aortic arches to the trachea and esophagus and also the degree of tracheal narrowing. Bronchoscopy can be useful in internally assessing the degree of tracheomalacia. Treatment is surgical and is indicated in all symptomatic patients. In the current era the risk of mortality or significant morbidity after surgical division of the lesser arch is low. However, the preoperative degree of tracheomalacia has an important impact on postoperative recovery. In certain patients it may take several months (up to 1–2 years) for the obstructive respiratory symptoms (wheezing) to disappear.
During pregnancy, prenatal ultrasound may reveal the abnormal course of the arch. On chest radiography, a right-sided aortic arch is visualized by the aortic knob (the prominent shadow of the aortic arch) that is located right from the sternum instead of left. Complex lesions are often assessed by MRI or CT.
Simple l-TGA does not immediately produce any visually identifiable symptoms, but since each ventricle is intended to handle different blood pressures, the right ventricle may eventually hypertrophy due to increased pressure and produce symptoms such as dyspnea or fatigue.
Complex l-TGA may produce immediate or more quickly-developed symptoms, depending on the nature, degree and number of accompanying defect(s). If a right-to-left or bidirectional shunt is present, the list of symptoms may include mild cyanosis.
In many cases, a bicuspid aortic valve will cause no problems. People with BAV may become tired more easily than those with normal valvular function and have difficulty maintaining stamina for cardio-intensive activities due to poor heart performance.
BAV frequently leads to significant complications in over one-third of affected individuals which often lead to significant morbidity and mortality. Notable complications of BAV include narrowing of the aortic valve opening, backward blood flow at the aortic valve, dilation of the ascending aorta, and infection of the heart valve.
Interrupted aortic arch is a very rare heart defect (affecting 3 per million live births) in which the aorta is not completely developed. There is a gap between the ascending and descending thoracic aorta. In a sense it is the complete form of a coarctation of the aorta. Almost all patients also have other cardiac anomalies, including a ventricular septal defect (VSD), aorto-pulmonary window, and truncus arteriosus. Interrupted aortic arch is often associated with DiGeorge syndrome.
A right-sided aortic arch does not cause symptoms on itself, however when it is accompanied by other vascular abnormalities, it may form a vascular ring, causing symptoms due to compression of the trachea and/or esophagus.
There are numerous types, differentiated by the extent of the defect. These types are:
- Type I: simple defects leading to communication between the ascending aorta and pulmonic trunk
- Type II: defects that extend to the origin of the right pulmonary artery
- Type III: anomalous origin of the right pulmonary artery from the ascending aorta
It is also classified as simple or complex. Simple defects are those that do not require surgical repair, occur with no other defects, or those that require minor stright-forward repair (ductus arteriosus, atrial septal defect). Complex defects are those that occur with other anatomical anomalies or require non-standard repair.
Fetal aortic stenosis is a disorder that occurs when the fetus’ aortic valve does not fully open during development. The aortic valve is a one way valve that is located between the left ventricle and the aorta, keeping blood from leaking back into the ventricle. It has three leaflets that separate when the ventricle contracts to allow blood to move from the ventricle to the aorta. These leaflets come together when the ventricle relaxes.
Fetal aortic valve stenosis can be diagnosed by echocardiography before birth. The diagnostic features include a poorly contracting left ventricle, aortic valve thickening/restriction, a varying degree of left ventricular hypertrophy and abnormal Doppler flow characteristics in the left heart. There may be little or no detectable flow into or out of the left side of the heart.
There are two screening periods, one during the first trimester and the other during the second trimester. Fetal aortic stenosis is typically detected between 18 and 24 weeks gestation. This early detection is important because it allows for parents to be counseled in a timely and rational manner, allowing for discussion of prognosis and possible outcomes. Another reason for this crucial early detection is because it allows for postnatal management planning.
Abdominal organs, including the liver, stomach, intestinal tract, and spleen may be randomly arranged throughout the left-right axis of the body. Distribution of these organs largely dictates treatment, clinical outcomes, and further evaluation.
The liver is typically symmetrical across the left-right axis in patients with situs ambiguous, which is abnormal. A majority of left atrial isomeric patients have defects throughout the biliary tree, which is responsible for bile production, even when the gall bladder is functional and morphologically normal. This biliary atresia can lead to acute problems such as nutrient malabsorption, pale stools, dark urine, and abdominal swelling. If this condition continues without proper treatment, cirrhosis and liver failure become a major concern. Biliary atresia is not usually observed in patients with right atrial isomerism.
Random positioning of the stomach is often one of the first signals of situs ambiguous upon examination. Malrotation of the entire intestinal tract, or improper folding and bulging of the stomach and intestines, results in bowel obstruction. This impairment leads to vomiting, abdominal distention, mucus and blood in the stool. Patients may also experience abdominal pain. Intestinal malrotation is more commonly identified in patients with right atrial isomerism than in those with left atrial isomerism.
Isomeric patients often experience disruptions to splenic development during embryogenesis, resulting in an overall lack a spleen (asplenia) or development of many spleens (polysplenia). Asplenia is most often observed in patients with right atrial isomerism. Polysplenia results in 90% of patients with left atrial isomerism. Although they have many spleens, each is usually ineffective resulting in functional asplenia. Rarely, left atrial isomeric patients have a single, normal, functional spleen. Patients lacking a functional spleen are in danger of sepsis and must be monitored.
Children with tetralogy of Fallot may develop "tet spells". These are acute hypoxia spells, characterized by shortness of breath, cyanosis, agitation, and loss of consciousness. This may be initiated by any event leading to decreased oxygen saturation or that causes decreased systemic vascular resistance, leading to increased venous return, which in turn leads to increased shunting through the ventricular septal defect.
Tet spells are characterized by a sudden, marked increase in cyanosis followed by syncope, and may result in hypoxic brain injury and death.
Older children will often squat during a tet spell. This increases systemic vascular resistance and allows for a temporary reversal of the shunt. It increases pressure on the left side of the heart, decreasing the right to left shunt thus decreasing the amount of deoxygenated blood entering the systemic circulation.
Tetralogy of Fallot results in low oxygenation of blood due to the mixing of oxygenated and deoxygenated blood in the left ventricle via the ventricular septal defect (VSD) and preferential flow of the mixed blood from both ventricles through the aorta because of the obstruction to flow through the pulmonary valve. This is known as a right-to-left shunt. The primary symptom is low blood oxygen saturation with or without cyanosis from birth or developing in the first year of life. If the baby is not cyanotic then it is sometimes referred to as a "pink tet". Other symptoms include a heart murmur which may range from almost imperceptible to very loud, difficulty in feeding, failure to gain weight, retarded growth and physical development, dyspnea on exertion, clubbing of the fingers and toes, and polycythemia. The baby may turn blue with breast feeding or crying.
In dextro-Transposition of the great arteries (dextro-TGA) deoxygenated blood from the right heart is pumped immediately through the aorta and circulated to the body and the heart itself, bypassing the lungs altogether, while the left heart pumps oxygenated blood continuously back into the lungs through the pulmonary artery. In effect, two separate "circular" (parallel) circulatory systems are created. It is called a cyanotic congenital heart defect (CHD) because the newborn infant turns blue from lack of oxygen.
In a normal heart, oxygen-depleted ("blue") blood is pumped from the right side of the heart, through the pulmonary artery, to the lungs where it is oxygenated. The oxygen-rich ("red") blood then returns to the left heart, via the pulmonary veins, and is pumped through the aorta to the rest of the body, including the heart muscle itself.
With d-TGA, deoxygenated blood from the right heart is pumped immediately through the aorta and circulated to the body and the heart itself, bypassing the lungs altogether, while the left heart pumps oxygenated blood continuously back into the lungs through the pulmonary artery. In effect, two separate "circular" (parallel) circulatory systems are created, rather than the "figure 8" (in series) circulation of a normal cardio-pulmonary system.
d vessels can present a large variety of , and/or . The effects may range from a change in blood pressure to an interruption in circulation, depending on the nature and degree of the misplacement and which vessels are involved.
Although "transposed" literally means "swapped", many types of TGV involve vessels that are in abnormal positions, while not actually being swapped with each other. The terms TGV and TGA are most commonly used in reference to dextro-TGA – in which the arteries "are" in swapped positions; however, both terms are also commonly used, though to a slightly lesser extent, in reference to levo-TGA – in which both the arteries and the ventricles are swapped; while other defects in this category are almost never referred to by either of these terms.
The symptoms/signs of pulmonary atresia that will occur in babies are consistent with cyanosis, some fatigue and some shortness of breath (eating may be a problem as well).
In the case of pulmonary atresia with ventricular septal defect, one finds that decreased pulmonary blood flow may cause associated defects such as:
- Tricuspid atresia
- Tetralogy of Fallot (severe)
- RV w/ double-outlet
l-TGA is often accompanied by other heart defects, the most common type being shunts such as atrial septal defect (ASD) including patent foramen ovale (PFO), ventricular septal defect (VSD), and patent ductus arteriosus (PDA). Stenosis of valves or vessels may also be present.
When no other heart defects are present it is called 'simple' l-TGA; when other defects are present it is called 'complex' l-TGA.
Isomerism of the bronchial tree is not typically damaging and presents no significant clinical complications. Pulmonary valve stenosis results in issues of blood flow to the lungs.