PA is a cardiac malformation that leads to severe consequences immediately after birth. Thus, it is commonly diagnosed within hours after birth. Children may be born cyanotic and their condition does not improve with oxygenation. Their skin is usually pale, clammy, and sometimes even cool.

Additional symptoms may be present right from the beginning and may aggravate when the ductus arteriosus closes or the symptoms may manifest only after closure of the ductus. Physiologically, the ductus arteriosus closes during the first days of life. However, there is an increased risk for patent ductus arteriosus in PA patients. Symptoms result from restricted oxygen supply to the whole body and generally consist of tachycardia, tachypnea, and dyspnea. An affected child tends to demonstrate feeding difficulties and fatigue. All these symptoms are not specific for either cardiovascular or respiratory problems.

• Atrial Septal Defect

  A thorough examination revealed platypnea-orthodeoxia syndrome due to an interatrial right-to-left shunt through a secundum atrial septal defect. Percutaneous closure with an Amplatzer Septal Occluder resulted in resolution of the syndrome. [ncbi.nlm.nih.gov]

  Therefore, the right atrium will empty its blood into the left atrium through a communication (patent foramen ovale or atrial septal defect) to mix with the blood returning from the lungs. [pedcard.rush.edu]

  It is usually associated with tetralogy of fallot, transposition of great vessels, or other cardiovascular anomalies. tricuspid atresia absence of the tricuspid orifice, circulation being made possible by an atrial septal defect. [medical-dictionary.thefreedictionary.com]

  The atrial septal defect was partly closed from each side with bilayer patches of autologous pericardium that overlapped at the center of the defect. [cardiothoracicsurgery.biomedcentral.com]

• Fatigue

  We believe that aneurysm formation of the conduit was a result of fatigue of the conduit wall under suprasystemic pressure. [ncbi.nlm.nih.gov]

  Signs and symptoms of severe defects in newborns include Rapid breathing Cyanosis - a bluish tint to the skin, lips, and fingernails Fatigue Poor blood circulation Many congenital heart defects cause few or no signs and symptoms. [nlm.nih.gov]

  Excessive fatigue or sweating. Pale looking skin that may be even sensitive to touch. Improper eating habits. Causes There is no cause of this disease as such. However, it is believed to cause difficulty during early pregnancy. [medanta.org]

  Symptoms of pulmonary atresia often appear within the first few hours or days of life and may include: Rapid breathing A bluish tinge to the skin, especially the lips, fingers, and toes Cool, pale, or clammy skin Breathing problems Fatigue or tiredness [my.clevelandclinic.org]

• Congestive Heart Failure

  Untreated, most patients die early in life, either with severe cyanosis and its attendant complications or with congestive heart failure and progressive pulmonary vascular disease. [doi.org]

  If the ductus arteriosus is of normal size, too much blood can actually pass through to the lungs, which can result in symptoms of congestive heart failure. [secondscount.org]

  At 2 months of age, the patient had no cyanosis and other signs of congestive heart failure. Echocardiography showed a completely normal heart with regression of the right ventricular hypertrophy. [annalspc.com]

  heart failure (CHF), in addition to complications of prolonged cyanosis and hypoxemia. [emedicine.com]

• Pulmonary Valve Stenosis

  Left ventricular dysfunction following neonatal pulmonary valve balloon dilation for pulmonary atresia or critical pulmonary stenosis. Pediatr Cardiol. 2015 Aug. 36 (6):1186-93. [Medline]. Schneider AW, Blom NA, Bruggemans EF, Hazekamp MG. [emedicine.com]

  If the stenosis is very severe, especially in babies, not enough blood crosses the valve to reach the lungs to become oxygenated. This is called critical pulmonary valve stenosis. [luriechildrens.org]

  […] and tricuspid valves Q22.0 Pulmonary valve atresia Q22.1 Congenital pulmonary valve stenosis Q22.2 Congenital pulmonary valve insufficiency Q22.3 Other congenital malformations of pulmonary valve Q22.4 Congenital tricuspid stenosis Q22.5 Ebstein's anomaly [icd10data.com]

• Fever

  Call your child’s healthcare provider if your child has fever, increased draining from the wound, or any severe symptoms. Follow all the instructions you are given. [hopkinsmedicine.org]

  The first patient died from a cardiac arrest and could not be resuscitated, in the context of severe respiratory distress and fever. The second died during an interventional catheterization, in the setting of acute RV failure with arrhythmia. [em-consulte.com]

  […] months), 2 patients with a previous fistula died: 1 of them at 2 months due to heart failure, undergoing a surgical closure of the fistula that evolved into an irreversible episode of shock; the other patient at 5 months, after being hospitalized for fever [revespcardiol.org]

  […] wall motion局所壁運動 regression退縮 regurgitant逆流　【形】 remodelingリモデリング reninレニン renovascular腎血管性　【形】 reperfusion再灌流 repolarization再分極 residual残存［性］、残留　【形】 resistance vessel抵抗血管 restenosis再狭窄 retrograde cardioplegia逆行性心筋保護 revascularization血管再生、血行再建 rheumatic fever [tokyo-med.ac.jp]

  Prevention of infective endocarditis: guidelines from the American Heart Association: a guideline from the American Heart Association Rheumatic Fever, Endocarditis, and Kawasaki Disease Committee, Council on Cardiovascular Disease in the Young, and the [circ.ahajournals.org]

• Tachypnea

  Symptoms result from restricted oxygen supply to the whole body and generally consist of tachycardia, tachypnea, and dyspnea. An affected child tends to demonstrate feeding difficulties and fatigue. [symptoma.com]

  blood flows from the right to the left heart via a shunt → deoxygenated blood enters the systemic circulation → cyanosis General clinical features “Blue b abies” : pale gray or blue skin color caused by cy anosis Nail clubbing Exertional dyspnea, tachypnea [amboss.com]

  It is manifested during infancy with cyanosis, dyspnea, and tachypnea. A congenital heart defect characterized by the narrowing or complete absence of the opening between the right ventricle and the pulmonary artery. [icd10data.com]

  These can include an abnormal heart sound during a heartbeat (heart murmur), rapid breathing (tachypnea), low blood pressure (hypotension), low levels of oxygen in the blood (hypoxemia), and a blue or purple tint to the skin caused by a shortage of oxygen [icdlist.com]

  On the other hand, fall of pulmonary vascular resistance during early infancy allows increase in pulmonary blood flow leading to heart failure and present with feeding difficulty, failure to thrive, signs of respiratory distress, tachypnea, tachycardia [heartviews.org]

• Clubbed Finger

  She was referred to our institution with the chief complaint of clubbing fingers. A thorough examination revealed platypnea-orthodeoxia syndrome due to an interatrial right-to-left shunt through a secundum atrial septal defect. [ncbi.nlm.nih.gov]

• Failure to Thrive

  Further symptoms include failure to thrive, characteristic heart murmurs, and symptoms of heart failure. The diagnosis is confirmed through visualization of the defect on echocardiography. [amboss.com]

  Failure to thrive in the absence of heart failure has been reported as a presenting symptom but the mechanism is unclear and can be secondary to underlying genetic abnormality. [heartviews.org]

  As a matter of fact, in these specific cases, the first surgical step is necessary but does not improve and even impairs clinical status, increasing the failure to thrive and signs of congestive heart failure. [em-consulte.com]

• Heart Disease

  Pulmonary atresia is a form of heart disease in which the pulmonary valve does not form properly. It is present from birth (congenital heart disease). [nlm.nih.gov]

  {at}gstt.nhs.uk Abstract Aim: The impact of prenatal diagnosis on morbidity and mortality for certain types of congenital heart disease (obstructive left heart lesions and transposition of the great arteries) is well established. [doi.org]

  We review the medical literature on pregnancy course as well as maternal and foetal outcome in cases involving this maternal congenital heart disease. [ncbi.nlm.nih.gov]

• Heart Failure

  Early outcomes are acceptable; however, the long-term sequelae include protein-losing enteropathy, declining functional status, increased pulmonary vascular resistance, heart failure, and hepatic and renal dysfunction. [ncbi.nlm.nih.gov]

  Further symptoms include failure to thrive, characteristic heart murmurs, and symptoms of heart failure. The diagnosis is confirmed through visualization of the defect on echocardiography. [amboss.com]

  Rarely, an infant with a large PDA or well-developed systemic collateral arteries may present at age 4-6 weeks with heart failure symptoms secondary to increased pulmonary blood flow. This heart failure may be very difficult to control medically. [emedicine.com]

  Overall, the modes of presentation in Tet-PA consisted of cyanosis (50%), heart failure (25%) or murmur with mild cyanosis with or without failure to thrive (25%) [5]. Newborns present with cyanosis with or without a heart murmur. [heartviews.org]

• Hypertension

  KEYWORDS: Aortopulmonary collaterals; Pulmonary atresia; Pulmonary hypertension; Tetralogy of Fallot [ncbi.nlm.nih.gov]

• Heart Murmur

  The main sign of heart valve disease is an unusual heartbeat sound called a heart murmur. Your doctor can hear a heart murmur with a stethoscope. But many people have heart murmurs without having a problem. [icdlist.com]

  Your child's physician may have also heard a heart murmur during a physical examination. A heart murmur is simply a noise caused by the turbulence of blood flowing through the openings that allow the blood to mix. [cincinnatichildrens.org]

  Sloan came into the world on February 28 th, 2017; doctors quickly picked up a heart murmur and decided to monitor it closely even though it wasn’t much of a concern initially (it is not uncommon for newborn babies to have... [savetheheartbeat.org]

  Using a stethoscope, a doctor will check for a heart murmur (an abnormal “whooshing” sound caused by blood not flowing properly). However, it is not uncommon for a heart murmur to be absent right at birth. [cdc.gov]

  […] include: Blue or purple tint to lips, skin and nails (cyanosis) Shortness of breath Difficulty feeding Heart murmur — the heart sounds abnormal when a doctor listens with a stethoscope Pulmonary atresia may be diagnosed before birth, with a fetal echocardiogram [chop.edu]

• Systolic Murmur

  Auscultatory finding: harsh systolic murmur that is best heard over Erb's point and left upper sternal border ; single second heart sound Diagnostics Pulse oximetry : ↓ SpO2 Hyperoxia test : to distinguish cardiac from pulmonary causes of cyanosis ECG [amboss.com]

  Cardiovascular examination revealed generalized cyanosis, single S2 and 1/6 systolic murmur best heard over the left sternal border. After three hours of birth, oxygen saturation by pulse oximetry was 24%. [annalspc.com]

  On auscultation there is a pan systolic murmur of VSD and machinery murmur of patent ductus arteriosus. With progressive right ventricular failure, hepatomegaly and prominent “a” wave of jugular venous pulse may be observed. [ispub.com]

  A grade 3/6 systolic murmur usually is audible along the lower left sternal border. A continuous murmur is best heard over the upper chest in the presence of a PDA. [emedicine.com]

• Hydrops Fetalis

  fetalis ), pleural effusions, pericardial effusions Postnatal Cyanosis Auscultation Tricuspid regurgitation : wide split S2, holosystolic murmur at the left sternal border Features unique to Ebstein anomaly : gallop rhythm with multiple clicks at the [amboss.com]

• Sweating

  Excessive fatigue or sweating. Pale looking skin that may be even sensitive to touch. Improper eating habits. Causes There is no cause of this disease as such. However, it is believed to cause difficulty during early pregnancy. [medanta.org]

  Symptoms may include: Bluish colored skin (cyanosis) Fast breathing Fatigue Poor eating habits (babies may get tired while nursing or sweat during feedings) Shortness of breath A medicine called prostaglandin E1 is usually used to help the blood move [nlm.nih.gov]

  Common symptoms of pulmonary atresia include: Difficulties in breathing, including shortness of breath and/or rapid breathing Becoming easily fatigued Cyanosis: Grey and blue skin tone Getting too tired to finish feeding Sweating during feedings Clammy [zofranlawsuitguide.com]

• Flushing

  An IV iopromide (Ultravist 370; Schering, Berlin, Germany) (2.0 mL/kg, 80 mL maximum volume) was injected by mechanical power injector (Injektron CT2, Medtron, France) followed by a 10-30ml saline flush at rates ranging from 1.5 to 2.5 ml/s. [journals.plos.org]

  Antibiotics are given, patients are fully heparinized, and continuous heparinized fluid infusion is flushed through large sheaths to prevent thrombus formation. [circ.ahajournals.org]

• Lethargy

  Symptoms may include: Rapid breathing Difficulty breathing Irritability Lethargy Pale, cool, or clammy skin Cyanosis The symptoms of pulmonary atresia may resemble other medical conditions or heart problems. [cincinnatichildrens.org]

  The signs and symptoms of Pulmonary Valve Atresia include: The baby turns blue soon after birth due to lack of oxygen in blood Rapid breathing: In order to increase the amount of oxygen, the baby tries to breathe faster Irritability and lethargy Cool [dovemed.com]

  Symptoms may include: rapid breathing difficulty breathing irritability lethargy pale, cool, or clammy skin The symptoms of pulmonary atresia may resemble other medical conditions or heart problems. [chd-uk.co.uk]

  Symptoms include: Rapid breathing Difficulty breathing Poor feeding Lethargy Pale, cool, or clammy skin Blue color of the lips or skin The symptoms of pulmonary atresia may look like other medical conditions or heart problems. [stanfordchildrens.org]

Symptoms present at birth or shortly after with severe cardiovascular or respiratory distress. If a child is born with cyanosis and this condition does not normalize within a very short time span, diagnostic measures need to be taken to identify its cause.

While arrhythmias may be detected in an electrocardiogram, echocardiography will directly visualize the defect pulmonary valve. If additional malformations such as a ventricular septal defect are present, these may also be seen in an echocardiographic examination.

If radiographic images will reveal a slightly enlarged heart. More striking may be the lack of or abnormal appearance of pulmonary vascular structures. Collaterals may be visible in the form of speckled areas. If pulmonary vessels seem to be well developed on one side and appear abnormal on the other, then the problem might be at the level of one of the two pulmonary arteries rather than cardiac. Pulmonary artery stenosis can then be considered in differential diagnosis.

Magnetic resonance imaging may help to further determine the vascular anatomy of the heart, lungs and surrounding tissues [8]. This may be facilitated by administering intravenous contrast agents [9]. A precise definition of the individual case is essential before planning surgical treatment.

Such pre-surgical information may be supplemented by results of cardiac catheterization.

• Oxygen Saturation Decreased

  His saturations increased from 70% to 85% following placement of the central shunt. At 16 months of age, his oxygen saturation decreased to 68%. [ncbi.nlm.nih.gov]

• Ventricular Hypertrophy

  [3] There was significant right ventricular hypertrophy in our patient. [annalspc.com]

  Right atrium and pericardium was normal. 2D analysis showed large left ventricle and right ventricular hypertrophy. There was subaortic ventricular septal defect (VSD) of 1.3 cm size with overriding of great vessels which were dilated. [ispub.com]

  Classic Tetralogy of Fallot consists of right ventricular outflow tract stenosis, malaligned ventricular septal defect, overriding of aorta and right ventricular hypertrophy. [heartviews.org]

  […] outflow obstruction ( RVOT ) due to pulmonary valve stenosis Right ventricular hypertrophy Ventricular septal defect ( VSD ) Overriding aorta (above the VSD ) Epidemiology Most common cause of cyanotic CHD ( ∼ 4/10,000 live births in the US) Etiology [amboss.com]

  Electrocardiogram shows normal QRS axis, right atrial enlargement, left ventricular hypertrophy with monopartite type and possible right ventricular hypertrophy with tripartite type. [omicsonline.org]

Treatment depends on the overall condition of the child, on the extent of the disease and the individual development of pulmonary arteries and collaterals. Treatment needs to be initiated as soon as possible since an untreated PA may be fatal within a few days.

To gain some time, the closure of the ductus arteriosus is prevented by administering prostaglandin E1 intravenously immediately following diagnosis. In children with PA, an atrial septal defect favors circulation and passage of blood low in oxygen to the left atrium and finally to the ductus arteriosus, the foramen ovale may be dilated in a procedure called balloon atrial septostomy. It may be performed via cardiac catheterization and does not require open surgery.

These treatments provide only short term relief. Surgical interventions are necessary to restore physiological heart function. There are different options that may be considered depending on the existence of a ventricular septal defect and development of pulmonary arteries. The former may prove beneficial for limited periods of time, the latter may be stimulated by increasing blood flow through the respective vessels. Certain interventions may only be carried out at a later time because pressure ratios do not favor them initially. Also, staged procedures are much better tolerated than one stage, major surgeries [10].

For instance, the pulmonary valve and parts of the pulmonary artery may be transplanted in the form of a homograft. If such treatment cannot be performed then a shunt may be temporarily placed between the right ventricle and the pulmonary artery. This shunt is removed in a second surgery that takes place when the child is approximately six months old. During that same intervention, the superior vena cava is connected to the pulmonary artery (hemi-Fontan procedure). This connection allows the blood to bypass the right heart. The same child needs to undergo a third surgery between the age of 3 to 6 years. During the third surgery the inferior vena cava is connected to the pulmonary artery (Fontan completion). Other surgical approaches may be chosen depending on the individual case.

Prognosis depends on the individual case, but is generally good if adequate treatment is provided. Depending on the extent of malformation, several surgeries may be required to ensure optimal heart function and oxygen supply to the body [7]. However even after surgical correction patients should undergo regular follow-ups during their lifetime.

The exact etiology of PA is not known. However, genetic factors seem to play a role in this and other cardiac developmental disorders. This hypothesis is supported by the fact that the risk for such diseases is increased in siblings of affected patients and in children born to parents who have been diagnosed with cardiac malformations themselves [2].

There is a high incidence of patent ductus arteriosus among PA patients. Furthermore, this malformation has been associated with a variety of other congenital defects, e.g., Alagille syndrome, DiGeorge syndrome, Down syndrome and VACTERL association (vertebral anomalies, anal atresia, cardiac defects, tracheoesophageal fistula, esophageal atresia, renal anomalies and limb defects).

The overall incidence of PA has been estimated in several studies and seems to range between 5 and 15 per 100,000 births [3] [4] [5]. PA only accounts for a small subset of congenital cardiac malformations [4] [5].

With regards to gender distribution, males seem to be affected slightly more than females.

Development of the pulmonary arteries, potential collaterals and the ductus arteriosus depends on demands for blood flow and as PA patients maintain pulmonary circulation by means of different blood vessels, distinct anatomical situations may be encountered in these individuals.

Poorly oxygenated blood may reach the lungs via native pulmonary arteries in this condition. Due to PA there is no direct connection between the right ventricle and these arteries and a patent ductus arteriosus may supply blood to the latter. If the ductus arteriosus closes, there may be major aortopulmonary collaterals that lead aortic blood into native pulmonary arteries. While most collaterals originate from the thoracic aorta, the existence of branches of bronchial, pleural or mammary arteries that serve as pulmonary collaterals has been described. In rare cases, collaterals may originate from coronary arteries [6]. If blood flow to the pulmonary trunk or to both pulmonary arteries is assured by a patent ductus arteriosus or collateral arteries, pulmonary vessels usually develop normally.

However, not all collaterals do necessarily connect to pulmonary arteries. They may instead reach the lungs themselves. Here, intrapulmonary vessel development will be altered.

In some cases, collaterals are the only vessels supplying the lungs with blood. If native pulmonary arteries have never been connected to the cardiovascular system, they do not develop and are virtually absent. Patients presenting this last anatomic situation are often diagnosed with pulmonary artery atresia to distinguish their condition from that of local PA, which mainly affects the pulmonary valve.

A significant number of patients with collateral arteries supplying blood to the pulmonary circulation also present with some degree of stenosis of these arteries. Stenosis often progresses over time.

Detailed knowledge about the individual development of pulmonary arteries, collaterals and ductus arteriosus is of utmost importance before deciding on surgical intervention. Also, the clinical presentation of the patient depends on their individual developmental disorder.

No measures can be recommended to prevent PA.

In healthy individuals, blood flow from the cardiac ventricles into the aorta and pulmonary artery occurs during ventricle contraction or systole. Aortic and pulmonary valves mark the limits of the left and right cardiac ventricle, respectively, and are open during this stage of the cardiac cycle. In order to enable subsequent filling of the ventricles, the myocardium relaxes and the respective valves close.

In patients suffering from pulmonary atresia (PA), the pulmonary valve remains closed because the orifice between its three leaflets is undeveloped. Thus, the blood flow from the right ventricle to the pulmonary artery is interrupted. This condition can be lethal if blood flow towards the lungs is not established via alternative routes. Prior to birth and in healthy fetuses, blood flows from the pulmonary artery through the ductus arteriosus directly into the aorta, thus bypassing the lungs. This ductus physiologically closes during the first days or weeks after birth. In PA patients it may persist in the form of a patent ductus arteriosus that allows blood flow from the aorta to the pulmonary artery. While a significant number of patients have pulmonary circulation via native pulmonary arteries, others develop major aortopulmonary collateral arteries. A combination of both pulmonary arteries and aortopulmonary collaterals have also been observed.

PA may be present as a single cardiac malformation or may be associated with a ventricular septal defect. In even more severe cases, PA occurs as part of a complex cardiac malformation [1]. Here, an abnormally small size of right cardiac structures can be observed. Underdevelopment of the right ventricle and related structures can result from disuse. PA and associated heart defects may be diagnosed prenatally using fetal echocardiography.

Due to the severity of the disease, symptoms manifest upon birth or soon after. Children are born cyanotic, with tachycardia and tachypnea.

In order to understand the condition of pulmonary atresia (PA), basic background knowledge regarding heart function is essential. There are four chambers in the heart and the two main chambers are called ventricles. The left ventricle is connected to the aorta and pumps blood rich in oxygen throughout the whole body. After cells and tissues use the oxygen, the blood is transported back to the heart via veins. The blood then reaches the right side of the heart and finally the right ventricle which is connected to the pulmonary artery and pumps blood into the lungs where it will be oxygenated before it reaches the left side of the heart.

In between the right ventricle and the pulmonary artery there is the pulmonary valve. This valve needs to open and close during regular heart pumping. However, in patients suffering from PA, this valve cannot open and the blood flow between the right ventricle and the pulmonary artery is interrupted. For the patient to survive, blood needs to find alternative ways to reach the lungs and tank oxygen. In some patients, vessels persisting from fetal life fulfill this task; in others, collateral vessels developed in utero perform this function.

Causes

The exact causes of PA are not known. The disease is congenital, i.e., it exists at the time of birth. Presumably, genetic factors play an important role: in certain families there are several cases of cardiac malformation. PA is sometimes associated with other heart defects such as an incomplete closure of the ventricular septum.

Symptoms

Due to the severity of the defect, symptoms often manifest immediately after birth. Children may be born cyanotic, i.e., with a bluish discoloration of their skin. Their skin may feel cool and clammy. Because of poor oxygen supply to the body, they may present with an accelerated heart rate, difficulty breathing and difficulties while feeding.

Diagnosis

Because first symptoms manifest shortly after birth, diagnostic measures need to be taken rapidly. A cyanosis that does not resolve in a very short period of time should prompt further diagnosis.

Heart murmurs can be heard easily using a stethoscope. An abnormal heart rhythm will be detected when recording an electrocardiogram. Echocardiography, an ultrasound examination of the heart, allows direct visualization of the underdeveloped pulmonary valve and other cardiac malformations if present.

Imaging studies such as X-rays and magnetic resonance imaging may reveal a slightly enlarged heart and abnormal formation of pulmonary vessels. The latter results from little use due to interruption of pulmonary circulation at the pulmonary valve.

Precise information regarding the individual vascular development of the child are necessary before any surgical intervention is planned.

Treatment

Initially, prostaglandin E1 may be administered to avoid closure of the ductus arteriosus, one of the above mentioned vessels that persist from fetal development and that may actually benefit a child suffering from PA. Also, a patent opening between the right and left atrium may be artificially dilated to improve circulation while awaiting surgery.

In less severe cases, the underdeveloped valve may be replaced with a homograft, i.e., a transplant obtained from an organ donor. Other children require more complex re-connection of major veins to the pulmonary arteries so the blood may bypass the right ventricle.

The overall prognosis is good if adequate treatment is provided in a timely manner. However, multiple surgeries are often necessary to reconstruct a functioning heart that may supply oxygen to the whole body. Regular follow-ups are needed for a lifetime.

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