Patent ductus arteriosus with small caliber may present with minimal signs or no signs at all. However, large caliber PDA may present with the following system wise symptomatology:

• General appearance: Patients will appear fatigued due to tissue hypoxia. Infants will have difficulty in eating because of breathlessness during swallowing.
• Integumentary system: Patients will appear cyanotic due to poor oxygen perfusion of the skin.
• Head and Neck: Dark discoloration around the eyes due to chronic cyanosis.
• Chest and heart: Machinery like murmur on auscultation due to volume overload through the PDA. Infants will exhibit tachypnea due pulmonary congestion.
• Abdomen: Ascites may occur with late stage heart failure.
• Extremities: Fingernail clubbing may be due to nail bed chronic hypoxic state. 

• Congestive Heart Failure

  PDA can place strain on the heart and lead to congestive heart failure. [ucsfbenioffchildrens.org]

  It can lead to congestive heart failure and sudden death. Heart failure in PDA develops because of an excessive workload on the heart. It enlarges so much that the heart wall is weakened, such that the heart can no longer pump blood effectively. [news-medical.net]

  […] palpitations, shortness of breath, and complications such as high blood pressure in the lungs, an enlarged heart, or congestive heart failure. [healthline.com]

  Clinical findings: Most children with PDA do not have heart related symptoms. If the ductus is large in size, symptoms of congestive heart failure may develop. [mottchildren.org]

• Asymptomatic

  Children with a small PDA are often asymptomatic, but may develop Infective Endocarditis. Surgery may be needed when the ductus is large, but in many cases the ductus can be closed using a spring coil introduced with a heart catheter. [rch.org.au]

  The clinical presentation is variable, and many patients can be asymptomatic for many years and even throughout their lives. We report the case of a 44-year-old female patient with a history of hemoptysis. [ncbi.nlm.nih.gov]

  We describe 2 cases illustrating the discovery of an asymptomatic PDA on routine physical examination of adult patients. [jabfm.org]

• Poor Feeding

  feeding Weight loss Failure to thrive Diagnosis and Treatment If a PDA is suspected, an echocardiogram of the heart will typically be performed. [preemies.about.com]

  This may be more obvious during times of exertion, such as feeding in an infant. Other symptoms in infants include sweating with exertion, poor feeding due to fatigue, and poor weight gain. [pediatricheartspecialists.com]

  However, some infants may have symptoms such as: Fast breathing Poor feeding habits Rapid pulse Shortness of breath Sweating while feeding Tiring very easily Poor growth Babies with PDA often have a heart murmur that can be heard with a stethoscope. [medlineplus.gov]

• Fatigue

  An adult with a large patent ductus arteriosus may present with fatigue, dyspnea or palpitations or in rare presentation with endocarditis. [ncbi.nlm.nih.gov]

  Other symptoms in infants include sweating with exertion, poor feeding due to fatigue, and poor weight gain. PDA’s may also predispose to an increased risk of lung infections such as pneumonia. [pediatricheartspecialists.com]

  Symptoms may go undetected into adulthood, but others may feel fatigued fast breathing, and low weight gain. Seek medical help if your child is experiencing symptoms. [bonsecours.com]

  This keeps blood pressure low and results in many disorders from oxygen starvation, such as fatigue and fainting. The disorder is usually detected in childhood, but in rare cases is not detected until the patient reaches adulthood. [house.wikia.com]

• Atrial Septal Defect

  It may be associated with various intracardiac defects, including atrial septal defects, ventricular septal defects, patent ductus arteriosus or more complicated structural congenital heart defects. [ncbi.nlm.nih.gov]

  References:[2][3][4][5][6][7][8][9] Atrial septal defect (ASD) Etiology Down syndrome Fetal alchohol syndrome Holt-Oram syndrome Pathophysiology Impaired growth or excessive resorption of the atrial septa in utero leads to atrial septal defects. [amboss.com]

  Septal defects The treatment of ventricular and atrial septal defects depends on the size of the hole. No treatment will be required if your child has a small septal defect that doesn't cause any symptoms or stretch on the heart. [nhs.uk]

  Do you have a child between 30 days and 17 years old who will have elective surgery to close an atrial septal defect? This study tests a tool that allows surgeons to tell the difference between various types of heart tissue and avoid injury. [nhlbi.nih.gov]

• Dyspnea

  […] including: Lethargy and weakness Fast or labored breathing Bounding (very strong) pulse Tachycardia (a heart rate exceeding the normal resting rate) Cyanosis (a blue-ish skin color due to a lack of oxygen), primarily affecting the lower extremities Dyspnea [preemies.about.com]

  An adult with a large patent ductus arteriosus may present with fatigue, dyspnea or palpitations or in rare presentation with endocarditis. [ncbi.nlm.nih.gov]

• Hoarseness

  Babies with a patent ductus arteriosus will often have a hoarse cry, a cough, pneumonia, heart failure with difficulty breathing, and poor weight gain. They may perspire when they are feeding and have a rapid heart and respiratory rate. [health.state.mn.us]

  On rare occasion an ADA is discovered during evaluations for perinatal distress, pulmonary hypertension, dyspnea, stridor, hoarseness, severe perinatal hypoxia, or neonatal thromboembolic events. FIGURE 14-1. Fetal echocardiogram. [accesspediatrics.mhmedical.com]

  If they do happen, they do not last long and may include hoarseness, infection, bleeding, or fluid around the lungs. The baby may need a machine to help with breathing for a short period of time, but this is rare. [nationwidechildrens.org]

• Tachypnea

  Infants will exhibit tachypnea due pulmonary congestion. Abdomen: Ascites may occur with late stage heart failure. Extremities: Fingernail clubbing may be due to nail bed chronic hypoxic state. [symptoma.com]

  Eg: tachypnea, tachycardia, growth retardation. Features of heart failure These symptoms are present in patients with large left to right shunt. Eg: tachypnea, tachycardia, growth retardation. [medicaljoyworks.com]

  Three-week to 6-week-old infants can present with tachypnea, diaphoresis, inability or difficulty with feeding, and weight loss or no weight gain. [emedicine.medscape.com]

  Symptoms may include failure to thrive, poor feeding, tachycardia, and tachypnea. A continuous murmur at the upper left sternal border is common. Diagnosis is by echocardiography. [merckmanuals.com]

• Cough

  […] catheterization procedure, call the doctor right away if your child has any of the following: Increased redness, draining, swelling, or bleeding at the incision or insertion site Fever 100.4°F (38°C) or higher Trouble feeding Tiredness Shortness of breath Cough [saintlukeskc.org]

  Babies with a patent ductus arteriosus will often have a hoarse cry, a cough, pneumonia, heart failure with difficulty breathing, and poor weight gain. They may perspire when they are feeding and have a rapid heart and respiratory rate. [health.state.mn.us]

  Annual flu vaccines are recommended, and parents should watch for signs of infection such as fever, cough, chills, and any difficulty breathing. [healthofchildren.com]

• Hemoptysis

  She continued to suffer from recurrent hemoptysis, even after switching from i.v. epoprostenol to i.v. treprostinil. [ncbi.nlm.nih.gov]

• Failure to Thrive

  […] to thrive Diagnosis and Treatment If a PDA is suspected, an echocardiogram of the heart will typically be performed. [preemies.about.com]

  Symptoms Failure to thrive, tachypnea, easy fatigability, tachycardia, and cyanosis may occur. Diagnosis Clinical examination, ECG, echocardiogram and chest X-ray are used to diagnose PDA. [symptoma.com]

  Infants and children with a small PDA are generally asymptomatic; infants with a large PDA present with signs of heart failure (eg, failure to thrive, poor feeding, tachypnea, dyspnea with feeding, tachycardia). [merckmanuals.com]

• Heart Failure

  It can lead to congestive heart failure and sudden death. Heart failure in PDA develops because of an excessive workload on the heart. It enlarges so much that the heart wall is weakened, such that the heart can no longer pump blood effectively. [news-medical.net]

  PDA can place strain on the heart and lead to congestive heart failure. [ucsfbenioffchildrens.org]

  In addition, heart failure, severe pulmonary hypertension, and calcification of the ductus may also exist. [ncbi.nlm.nih.gov]

  This extra blood flow into the lungs can overload the lungs and put more burden on the heart to pump this extra blood. Some babies may need more support from a ventilator and have symptoms of congestive heart failure. [cincinnatichildrens.org]

• Heart Murmur

  Many babies and children will have no symptoms, and the presence of a PDA is only noticed because of a Heart Murmur. [chfed.org.uk]

  A patient with a PDA often comes to attention due to the presence of a heart murmur. This simply refers to the sound that blood is making as it flows from the aorta into the lungs. [pediatricheartspecialists.com]

  However, in premature infants, a heart murmur may not be heard. The health care provider may suspect the condition if the infant has breathing or feeding problems soon after birth. Changes may be seen on chest x-rays. [medlineplus.gov]

• Heart Disease

  Congenital heart disease. In: Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 10th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 62. Updated by: Michael A. [medlineplus.gov]

  Congenital heart disease. In: Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 10th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 62. [mountsinai.org]

  Major aortopulmonary collateral arteries are abnormal vascular structures that may be seen in cyanotic diseases that progress with reduced pulmonary flow. They occur rather rarely in the absence of cyanotic congenital heart disease. [ncbi.nlm.nih.gov]

• Cyanosis

  However, when the PDA is larger, it can result in more significant symptoms, including: Lethargy and weakness Fast or labored breathing Bounding (very strong) pulse Tachycardia (a heart rate exceeding the normal resting rate) Cyanosis (a blue-ish skin [preemies.about.com]

  At that time, there was differential cyanosis with clubbing and lower oxygen saturations in the toes (82%) compared with her fingers (95%). [ncbi.nlm.nih.gov]

  cyanosis in the lower extremities when the Eisenmenger reaction occurs For specific features, see “Clinical features” in the subsections below. [amboss.com]

• Continuous Murmur

  […] loud continuous murmur 9. [slideshare.net]

  Continuous murmur. S2 is obliterated by the waxing and waning of the murmur. (Reproduced, with permission, from T. Anthony Don Michael, MD. Mastering Auscultation [CD-ROM], 2000.) Play Video B. [accessmedicine.mhmedical.com]

  She presented not only polydipsia, polyphagia, and weight loss but also small elfin face, distended abdomen, enlarged clitoris, hypertrichosis, acanthosis nigricans of the neck, decreased subcutaneous fat and 3/6 continuous murmur radiating to the right [ncbi.nlm.nih.gov]

  Classic continuous machinery murmur best heard in the left second inter costal space. [medicaljoyworks.com]

  A grade 1 to 4/6 continuous murmur is characteristic. If the murmur is loud, it has a “machinery-sounding” quality. [merckmanuals.com]

The diagnosis of PDA in infants is initially done by clinical examination by the attending pediatrician. However, additional tests may be recommended to confirm the diagnosis of PDA. The following diagnostic modalities are used in the examination of PDA patients:

• Electrocardiography (ECG): A left ventricular hypertrophy may be demonstrated by voltage in ECG.
• Chest X-ray: This radiograph will show a prominent left atria, left ventricle and ascending aorta. There is an increased pulmonary markings in a significant shunt.
• Echocardiography: A two dimensional imaging of the heart with colored Doppler studies can identify the patent ductus radiographically [3]. A suprasternal view of the aortic side of the PDA in echocardiogram can accurately reveal its diameter [4].

• Prominent Aortic Knob

  With greater degrees of shunting, the chest x-ray may reveal a prominent main pulmonary artery, a prominent aortic knob, increased pulmonary vascular markings, and enlargement of the cardiac silhouette. [youtube.com]

• Right Axis Deviation

  It is agreed by most authors writing on the subject that the electrocardiographic findings in patent ductus are usually normal, although prolonged P-R intervals, left axis, and occasionally right axis deviation are also seen (5, 8, 11). [pubs.rsna.org]

• Incomplete Right Bundle Branch Block

  His chest X-ray showed cardiomegaly and enlargement of the left pulmonary hilum, and an electrocardiogram revealed sinus tachycardia with incomplete right bundle branch block ( Figure 1 A). [elsevier.pt]

• Biventricular Hypertrophy

  With a larger degree of shunting, there may be biventricular hypertrophy. [youtube.com]

  A large PDA may be associated with signs of biventricular hypertrophy (BVH) and in those with pulmonary hypertension, right ventricular hypertrophy (RVH) may be present. [patient.info]

  The electrocardiography showed sinus tachycardia and biventricular hypertrophy. The chest X-ray showed a normal cardiac silhouette and pulmonary circulation, and widening of the superior mediastinum (fig. 1). [scielo.br]

  In the patient with a large ductus arteriosus and elevated pulmonary artery pressure, signs of right atrial enlargement and biventricular hypertrophy are frequently present. [circ.ahajournals.org]

• Pleural Effusion

  No pneumothorax or pleural effusions. Multiple locules of gas and associated stranding/hematoma are in keeping with a soft tissue injury anterior to the midshaft of the left clavicle. No underlying fracture of the imaged clavicle. [radiopaedia.org]

  (2) heart (2) hrudník (2) imaging methods (2) lungs (2) magnetic resonance imaging (2) magnetická resonance (2) ovariální hyperstimulační syndrom (2) pleural effusion (2) plíce (2) pneumothorax (2) pulmonary hypertension (2) pulmonary oedema (2) radiologie [portal.mefanet.cz]

  Bilateral pleural effusions and atelectasis are also seen. [ajronline.org]

In premature babies, the PDA may close spontaneously within the first two years of life. This may no longer need any treatment especially when the PDA is small with minimal symptoms. In full term babies, the non-closure after a few weeks from birth may suggest that it may never will. The first line treatment for the closure of PDA in newborns is the use of indomethacin and ibuprofen. Both cyclooxygenase inhibitors are equipotent in PDA closure capabilities [5].

However, excess indomethacin may cause renal toxicity; thus, dose reduction is imperative if warranted [6]. Ibuprofen may be given orally or intravenously with no significant advantage over the other [7]. These regimens are noted to have fewer side effects and may significantly help in the closure if given at an early stage.

An invasive procedure known as trans-catheter device closure may be implored by blocking the PDA with a small metal coil to block the blood flow, this device is introduced through a small cardiac catheter [8]. When conservative medical management fails, a surgical repair of the PDA by ligation may be indicated by doing a chest incision in through the baby’s ribs [9]. Cardiac surgery in infants post no greater risk and threats than those given ibuprofen and indomethacin [10].

Prognosis in patent ductus arteriosus is dependent on ductal size. Smaller sized PDA may convey cardiac symptoms but infants may thrive with some difficulty. Small PDA that occurs even prematurity that appears as a solitary lesion caries a good prognosis.

The patent ductus in premature infants may close spontaneously within the first 3 months of life in 72-75% of cases. The use of prophylactic ibuprofen may lead to a 92% closure rate. However, larger PDA may lead to heart failure, pulmonary hypertension and recurrent infection of the lungs.

Complications

Patients with small PDA may not lead to any complications but larger PDA may complicate into either of these clinical disorders if left untreated:

• Pulmonary hypertension: The increased blood flow the patent ductus may cause permanent damage to the lungs.
• Eisenmenger’s syndrome: An irreversible type of pulmonary hypertension that causes a reversal of blood flow.
• Bacterial endocarditis: The PDA increases the risk of patients to any infection of the myocardial endothelium (inner lining).
• Heart failure: This is a chronic outcome if the heart muscles over works due to volume overload 
• Cardiac dysrhythmias: Arrhythmias usually develop with the enlargement of the heart.

The congenital heart defect in patent ductus arteriosus is believed to have developed early in the embryology of the heart muscle. The exact mechanism is still unknown to medical science and is continually being researched up to this day. Research scientists believes in the major role of genetics and environmental factors in the development of PDA.

Infants that suffer congenital rubella syndrome whereby the mother had rubella in the first trimester of pregnancy are most prone to PDA. Maternal intake of amphetamine, alcohol and phenytoin may be a causative factor in its development. Premature infants has a very high likelihood of a persistent ductus.

In the United States, the general incidence of patent ductus arteriosus is 6 to 20 per 100,000 live births. Premature infants less than 28 weeks old has a PDA incidence of 60% while those born more than 32 weeks gestation has an incidence rating of 20% for PDA.

Patent ductus arteriosus as an isolated case represents 5 to 10% of all congenital heart diseases. Females are more prone with a 2:1 ratio as compared with male infants. A great deal of children are usually left undiagnosed until they get older.

The failure of the ductus closure among premature neonates are primarily due to poor prostaglandin metabolism from an immature lung. The failure in prostaglandin metabolism is usually brought about by perinatal asphyxia, hypoxemia, increased pulmonary blood flow, renal failure, and respiratory disorders. It was also postulated that cyclooxygenase-2 (COX-2) induction, an isoform of the COX producing prostaglandin can prevent the duct from closing.

There is no definitive cause for PDA; thus, preventive measures in ensuring that PDA doesn’t occur in your baby are hard to determine. This precludes that one must do everything to have a healthy pregnancy to prevent PDA and other congenital diseases of the infant. The following tips are most helpful in having a healthy pregnancy:

• Regular prenatal care with your doctor
• Exercise regularly
• Balanced diet
• Avoid infections
• Avoid smoking, alcohol, X-ray and illegal drugs
• Diabetic mothers should have their glucose controlled

Patent ductus ateriosus or PDA is a clinically characterized as the persistent fetal connection (ductus arteriosus) between the two major vessels from the heart, pulmonary artery and aorta after birth that usually results into the shunting of blood from left-to-right. The ductus arteriosus is a vestigial vessel that shunts the blood from the heart directly to the aorta, this vessel physiologically closes when the lung expands after birth which usually happens within 3 months from birth [1].

The persistence of the vessel is clinically referred to as patent ductus arteriosus that transmits poorly oxygenated blood to the body manifested as failure to thrive, poor feeding, tachycardia, and tachypnea in infants. The symptomatic persistence of the ductus arteriosus may need cardiac surgery or catheter-based correction to achieve normalcy [2].

Definition

Patent ductus arteriosus is a clinical disease characterized by the persistent fetal connection between the pulmonary artery and the aorta.

Cause

Genetics, rubella infection, amphetamine, phenytoin, and alcohol may cause the disorder.

Symptoms

Failure to thrive, tachypnea, easy fatigability, tachycardia, and cyanosis may occur. 

Diagnosis

Clinical examination, ECG, echocardiogram and chest X-ray are used to diagnose PDA.

Treatment and follow-up

Indomethacin and ibuprofen, trans-catheter closure device and surgical repair are the common treatment options.

1. Cassels DE, Bharati S, Lev M. The natural history of the ductus arteriosus in association with other congenital heart defects. Perspect Biol Med. Summer 1975; 18(4):541-72.
2. Schneider DJ. The patent ductus arteriosus in term infants, children, and adults. Semin Perinatol. 2012; 36(2):146-53 (ISSN: 1558-075X)
3. Amoozgar H, Soltani M, Cheriki S. Estimation of patent ductus arteriosus diameters by colour Doppler echocardiography in children. Cardiol Young. 2010; 20(6):648-53 (ISSN: 1467-1107)
4. Zhang XY, Cao TS, Yuan LJ, Liu J, Duan YY. Value of the echocardiographic suprasternal view for diagnosis of patent ductus arteriosus subtypes. J Ultrasound Med. 2012; 31(9):1421-7 (ISSN: 1550-9613)
5. Ohlsson A, Walia R, Shah S. Ibuprofen for the treatment of patent ductus arteriosus in preterm and/or low birth weight infants. Cochrane Database Syst Rev. Jan 23 2008; CD003481
6. Attridge JT, Kaufman DA, Lim DS. B-type natriuretic peptide concentrations to guide treatment of patent ductus arteriosus. Arch Dis Child Fetal Neonatal Ed. May 2009; 94(3):F178-82.
7. Olukman O, Calkavur S, Ercan G, Atlihan F, Oner T, Tavli V, Kultursay N. Comparison of oral and intravenous Ibuprofen for medical closure of patent ductus arteriosus: which one is better? Congenit Heart Dis. 2012; 7(6):534-43 (ISSN: 1747-0803)
8. Karagöz T, Akin A, Ertuğrul I, Aykan HH, Alehan D, Ozer S, Ozkutlu S. Closure of the patent ductus arteriosus with the Amplatzer Duct Occluder II: a clinical experience. Acta Cardiol. 2012; 67(6):675-80 (ISSN: 0001-5385)
9. Kang SL, Samsudin S, Kuruvilla M, Dhelaria A, Kent S, Kelsall WA. Outcome of patent ductus arteriosus ligation in premature infants in the East of England: a prospective cohort study. Cardiol Young. 2013; 23(5):711-6 (ISSN: 1467-1107)
10. Malviya M, Ohlsson A, Shah S. Surgical versus medical treatment with cyclooxygenase inhibitors for symptomatic patent ductus arteriosus in preterm infants. Cochrane Database Syst Rev. Jan 23 2008; CD003951.