Patent ductus arteriosus | |
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Other names | Persistent ductus arteriosus |
Diagram of a cross-section through a heart with PDA | |
Specialty | Cardiac surgery, paediatrics |
Symptoms | Shortness of breath, failure to thrive, tachycardia, heart murmur |
Complications | Heart failure, Eisenmenger's syndrome, pulmonary hypertension |
Causes | Idiopathic |
Risk factors | Preterm birth, congenital rubella syndrome, chromosomal abnormalities, genetic conditions |
Diagnostic method | Echocardiography, Doppler, X-ray |
Prevention | Screening at birth, high index of suspicion in neonates at risk |
Treatment | Nonsteroidal anti-inflammatory drugs (NSAIDs), surgery |
Patent ductus arteriosus (PDA) is a medical condition in which the ductus arteriosus fails to close after birth: this allows a portion of oxygenated blood from the left heart to flow back to the lungs from the aorta, which has a higher blood pressure, to the pulmonary artery, which has a lower blood pressure. Symptoms are uncommon at birth and shortly thereafter, but later in the first year of life there is often the onset of an increased work of breathing and failure to gain weight at a normal rate. With time, an uncorrected PDA usually leads to pulmonary hypertension followed by right-sided heart failure.
The ductus arteriosus is a fetal blood vessel that normally closes soon after birth. This closure is caused by vessel constriction immediately after birth as circulation changes occur, followed by the occlusion of the vessel’s lumen in the following days. [1] In a PDA, the vessel does not close, but remains patent (open), resulting in an abnormal transmission of blood from the aorta to the pulmonary artery. PDA is common in newborns with persistent respiratory problems such as hypoxia, and has a high occurrence in premature newborns. Premature newborns are more likely to be hypoxic and have PDA due to underdevelopment of the heart and lungs.
If the congenital defect transposition of the great vessels is present in addition to a PDA, the PDA is not surgically closed since it is the only way that oxygenated blood can mix with deoxygenated blood. In these cases, prostaglandins are used to keep the PDA open, and NSAIDs are not administered until surgical correction of the two defects is completed.
In full-term newborns, PDA occurs in 1 in 2,000 births, and accounts for 5–10% of congenital heart disease cases. PDA occurs in 20–60% of all premature newborns, where its incidence inversely linked with gestational age and weight. [2]
Common symptoms include:[ citation needed ]
Signs include:[ citation needed ]
People with patent ductus arteriosus typically present in good health, with normal respirations and heart rate. If the PDA is moderate or large, widened pulse pressure and bounding peripheral pulses are frequently present, reflecting increased left ventricular stroke volume and diastolic run-off of blood into the (initially lower-resistance) pulmonary vascular bed. [4] Eisenmenger physiology is pulmonary hypertension due to a left-to-right shunt. Prominent suprasternal and carotid pulsations may be noted secondary to increased left ventricular stroke volume. [5]
Known risk factors include: [6]
PDA is usually diagnosed using noninvasive techniques. Echocardiography (in which sound waves are used to capture the motion of the heart) and associated Doppler studies are the primary methods of detecting PDA. Electrocardiography (ECG), in which electrodes are used to record the electrical activity of the heart, is not particularly helpful as no specific rhythms or ECG patterns can be used to detect PDA. [7]
A chest X-ray may be taken, which reveals overall heart size (as a reflection of the combined mass of the cardiac chambers) and the appearance of blood flow to the lungs. A small PDA most often accompanies a normal-sized heart and normal blood flow to the lungs. A large PDA generally accompanies an enlarged cardiac silhouette and increased blood flow to the lungs.[ citation needed ]
Some evidence suggests that intravenous NSAIDs, such as indomethacin, administration on the first day of life to all preterm infants reduces the risk of developing a PDA and the complications associated with PDA. [8] Intravenous indomethacin treatment in premature infants also may reduce the need for surgical intervention. [8] Administering ibuprofen probably helps to prevent PDA and reduce the need for surgery but it also likely increases the risk of kidney complications. [9]
Symptomatic PDA can be treated with both surgical and non-surgical methods. [10]
Neonates without adverse symptoms may simply be monitored as outpatients.[ citation needed ]
Surgically, the DA may be closed by ligation (though support in premature infants is mixed). [11] This can either be performed manually and be tied shut, or with intravascular coils or plugs that leads to formation of a thrombus in the DA.[ citation needed ]
Devices developed by Franz Freudenthal block the blood vessel with woven structures of nitinol wire. [12] Newer procedures performed effectively in older, bigger children include catheter PDA occlusion and video-assisted thoracoscopic PDA clipping. [13]
Because prostaglandin E2 is responsible for keeping the DA open, NSAIDs (which can inhibit prostaglandin synthesis) such as indomethacin or a special form of ibuprofen have been suggested as therapy to initiate PDA closure. [3] [14] [15] Findings from a 2015 systematic review concluded that, for closure of a PDA in preterm and/or low birth weight infants, ibuprofen is as effective as indomethacin. It also causes fewer side effects (such as transient acute kidney injury) and reduces the risk of necrotising enterocolitis. [16] The evidence supporting the effectiveness and safety of paracetamol (acetaminophen) is less clear. [17] A review and meta-analysis showed that paracetamol may be effective for closure of a PDA in preterm infants. [18] A 2018 network meta-analysis that compared indomethacin, paracetamol and ibuprofen at different doses and administration schemes among them found that a high dose of oral ibuprofen may offer the highest likelihood of closure in preterm infants. [19] [20] [21] However, a 2020 systematic review found that early (≤7 days of life) or very early (≤72 hours of life) pharmacological treatment of symptomatic PDA does not reduce death or other poor clinical outcomes in preterm infants but instead increases their exposure to NSAIDS. [22] Vasodilator therapy is suitable for people with Eisenmenger physiology. To assess improvement in people with Eisenmenger physiology, close monitory of toe oxygen saturation is required, for there exists a chance of reversal after a successful right-to-left shunt [ citation needed ]
While indometacin can be used to close a PDA, some neonates require their PDA be kept open. Keeping a ductus arteriosus patent is indicated in neonates born with concurrent heart malformations, such as transposition of the great vessels. Drugs such as alprostadil, a PGE-1 analog, can be used to keep a PDA open until the primary defect is corrected surgically.[ citation needed ]
If left untreated, the disease may progress from left-to-right shunt (acyanotic heart) to right-to-left shunt (cyanotic heart), called Eisenmenger's syndrome. Pulmonary hypertension is a potential long-term outcome, which may require a heart and/or lung transplant. Another complication of PDA is intraventricular hemorrhage.[ citation needed ]
Robert Edward Gross, MD performed the first successful ligation of a patent ductus arteriosus on a seven-year-old girl at Children's Hospital Boston in 1938. [23]
Since PDA is usually identified in infants, it is less common in adults, but it can have serious consequences, and is usually corrected surgically upon diagnosis.[ citation needed ]
Paracetamol, or acetaminophen, is a non-opioid analgesic and antipyretic agent used to treat fever and mild to moderate pain. It is a widely used over-the-counter medication. Common brand names include Tylenol and Panadol.
Tetralogy of Fallot (TOF), formerly known as Steno-Fallot tetralogy, is a congenital heart defect characterized by four specific cardiac defects. Classically, the four defects are:
Preterm birth, also known as premature birth, is the birth of a baby at fewer than 37 weeks gestational age, as opposed to full-term delivery at approximately 40 weeks. Extreme preterm is less than 28 weeks, very early preterm birth is between 28 and 32 weeks, early preterm birth occurs between 32 and 34 weeks, late preterm birth is between 34 and 36 weeks' gestation. These babies are also known as premature babies or colloquially preemies or premmies. Symptoms of preterm labor include uterine contractions which occur more often than every ten minutes and/or the leaking of fluid from the vagina before 37 weeks. Premature infants are at greater risk for cerebral palsy, delays in development, hearing problems and problems with their vision. The earlier a baby is born, the greater these risks will be.
dextro-Transposition of the great arteries is a potentially life-threatening birth defect in the large arteries of the heart. The primary arteries are transposed.
The ductus arteriosus, also called the ductus Botalli, named after the Italian physiologist Leonardo Botallo, is a blood vessel in the developing fetus connecting the trunk of the pulmonary artery to the proximal descending aorta. It allows most of the blood from the right ventricle to bypass the fetus's fluid-filled non-functioning lungs. Upon closure at birth, it becomes the ligamentum arteriosum.
Blue baby syndrome can refer to conditions that cause cyanosis, or blueness of the skin, in babies as a result of low oxygen levels in the blood. This term has traditionally been applied to cyanosis as a result of:.
Infant respiratory distress syndrome (IRDS), also known as surfactant deficiency disorder (SDD), and previously called hyaline membrane disease (HMD), is a syndrome in premature infants caused by developmental insufficiency of pulmonary surfactant production and structural immaturity in the lungs. It can also be a consequence of neonatal infection and can result from a genetic problem with the production of surfactant-associated proteins.
A congenital heart defect (CHD), also known as a congenital heart anomaly, congenital cardiovascular malformation, and congenital heart disease, is a defect in the structure of the heart or great vessels that is present at birth. A congenital heart defect is classed as a cardiovascular disease. Signs and symptoms depend on the specific type of defect. Symptoms can vary from none to life-threatening. When present, symptoms are variable and may include rapid breathing, bluish skin (cyanosis), poor weight gain, and feeling tired. CHD does not cause chest pain. Most congenital heart defects are not associated with other diseases. A complication of CHD is heart failure.
Eisenmenger syndrome or Eisenmenger's syndrome is defined as the process in which a long-standing left-to-right cardiac shunt caused by a congenital heart defect causes pulmonary hypertension and eventual reversal of the shunt into a cyanotic right-to-left shunt. Because of the advent of fetal screening with echocardiography early in life, the incidence of heart defects progressing to Eisenmenger syndrome has decreased.
The Blalock–Thomas–Taussig shunt, previously known as the Blalock–Taussig Shunt, is a surgical procedure used to increase blood flow to the lungs in some forms of congenital heart disease such as pulmonary atresia and tetralogy of Fallot, which are common causes of blue baby syndrome. The procedure involves connecting a branch of the subclavian artery or carotid artery to the pulmonary artery. In modern practice, this procedure is temporarily used to direct blood flow to the lungs and relieve cyanosis while the infant is waiting for corrective or definitive surgery when their heart is larger. The BTT shunt is used in the first step of the three-stage palliation.
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Hypoplastic left heart syndrome (HLHS) is a rare congenital heart defect in which the left side of the heart is severely underdeveloped and incapable of supporting the systemic circulation. It is estimated to account for 2-3% of all congenital heart disease. Early signs and symptoms include poor feeding, cyanosis, and diminished pulse in the extremities. The etiology is believed to be multifactorial resulting from a combination of genetic mutations and defects resulting in altered blood flow in the heart. Several structures can be affected including the left ventricle, aorta, aortic valve, or mitral valve all resulting in decreased systemic blood flow.
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Persistent truncus arteriosus (PTA), often referred to simply as truncus arteriosus, is a rare form of congenital heart disease that presents at birth. In this condition, the embryological structure known as the truncus arteriosus fails to properly divide into the pulmonary trunk and aorta. This results in one arterial trunk arising from the heart and providing mixed blood to the coronary arteries, pulmonary arteries, and systemic circulation. For the International Classification of Diseases (ICD-11), the International Paediatric and Congenital Cardiac Code (IPCCC) was developed to standardize the nomenclature of congenital heart disease. Under this system, English is now the official language, and persistent truncus arteriosus should properly be termed common arterial trunk.
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