[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Conditions](https://durgical.com/en/conditions/) › Patent ductus arteriosus

[Conditions](https://durgical.com/en/conditions/) · [Chest](https://durgical.com/en/anatomy/region/chest/)

# Patent ductus arteriosus

Patent ductus arteriosus is when a fetal vessel joining the aorta and pulmonary artery stays open after birth, sending extra blood to the lungs.

Updated 2026-10-29

## Structures involved

Tap one to see what it is and open it in 3D.

- [Ligamentum arteriosum](https://durgical.com/en/anatomy/ligamentum-arteriosum/)
- [Pulmonary trunk](https://durgical.com/en/anatomy/pulmonary-trunk/)
- [Aortic arch](https://durgical.com/en/anatomy/aortic-arch/)
- [Thoracic aorta](https://durgical.com/en/anatomy/thoracic-aorta/)
- [Pulmonary arteries](https://durgical.com/en/anatomy/right-pulmonary-artery/)
- [Left atrium](https://durgical.com/en/anatomy/left-atrium/)
- [Left ventricle](https://durgical.com/en/anatomy/left-ventricle/)
- [Recurrent laryngeal nerves](https://durgical.com/en/anatomy/recurrent-laryngeal-nerve/)
- [Subclavian artery](https://durgical.com/en/anatomy/right-subclavian-artery/)

## In biochemistry

- [Eicosanoids: prostaglandins, thromboxanes and leukotrienes](https://durgical.com/en/biochemistry/topics/eicosanoids-prostaglandins-thromboxanes-and-leukotrienes/)

## Microorganisms that cause it

- [Rubella virus](https://durgical.com/en/microbiology/rubella-virus/)

## In embryology

- [Fetal circulation and the changes at birth](https://durgical.com/en/embryology/fetal-circulation-and-the-changes-at-birth/)
- [Fetal lung, kidney and brain maturation: what preterm birth interrupts](https://durgical.com/en/embryology/fetal-lung-kidney-and-brain-maturation-what-preterm-birth-interrupts/)
- [Pharyngeal arches: nerve, muscles, skeleton and artery (the table)](https://durgical.com/en/embryology/pharyngeal-arches-nerve-muscles-skeleton-and-artery/)
- [Fourth and sixth pharyngeal arches: the larynx and the vagus nerve](https://durgical.com/en/embryology/fourth-and-sixth-pharyngeal-arches-the-larynx-and-the-vagus-nerve/)
- [Embryonic heart structures and their adult derivatives (the table to know)](https://durgical.com/en/embryology/embryonic-heart-structures-and-their-adult-derivatives/)
- [Aortic arch arteries and their derivatives](https://durgical.com/en/embryology/aortic-arch-arteries-and-their-derivatives/)
- [Patent ductus arteriosus](https://durgical.com/en/embryology/patent-ductus-arteriosus/)
- [Congenital rubella syndrome](https://durgical.com/en/embryology/congenital-rubella-syndrome/)

## In physiology

- [Physiology of congenital shunts](https://durgical.com/en/physiology/physiology-of-congenital-shunts/)
- [Fetal circulation and the transition at birth](https://durgical.com/en/physiology/fetal-circulation-and-the-transition-at-birth/)

## Why it happens

- [Arachidonic acid metabolites in inflammation, and the drugs that block them](https://durgical.com/en/general-pathology/arachidonic-acid-metabolites-in-inflammation-and-the-drugs-that-block-them/)
- [Neonatal respiratory distress syndrome: surfactant and hyaline membranes](https://durgical.com/en/general-pathology/neonatal-respiratory-distress-syndrome-surfactant-and-hyaline-membranes/)
- [Prematurity and fetal growth restriction](https://durgical.com/en/general-pathology/prematurity-and-fetal-growth-restriction/)

## What it is

Persistence after birth of the ductus arteriosus, the fetal vessel that joins the pulmonary artery to the aorta. Blood then flows from the aorta into the lungs, overloading the left heart.

## Who gets it

Much more frequent in premature babies, especially the most preterm, than in term babies. It is also more common in children born at high altitude, which is relevant in Andean cities, and after congenital rubella.

## Causes

- Failure of normal closure: the duct usually closes in the first days as oxygen rises and prostaglandin levels fall, then becomes the [ligamentum arteriosum](https://durgical.com/en/anatomy/ligamentum-arteriosum/)
- Immature duct tissue in premature babies
- Congenital rubella
- Genetic syndromes, such as trisomy 21

## Risk factors

- Prematurity and low birth weight
- Neonatal respiratory distress syndrome
- Maternal rubella in pregnancy
- Birth at high altitude
- Female sex
- Genetic syndromes

## Pathophysiology

After birth aortic pressure exceeds pulmonary pressure through the whole cycle, so a continuous left-to-right shunt overloads the lungs, [left atrium](https://durgical.com/en/anatomy/left-atrium/) and [left ventricle](https://durgical.com/en/anatomy/left-ventricle/). Run-off in diastole widens the pulse pressure and, in preterm babies, can reduce gut and [kidney](https://durgical.com/en/anatomy/kidney/) perfusion. A long-standing large duct can cause pulmonary vascular disease and reversal, with cyanosis of the lower body only.

## Classification

- Silent: tiny, found only on echocardiography
- Small, moderate or large according to the shunt
- In preterm babies: haemodynamically significant or not

## Symptoms and signs

- Continuous «machinery» murmur below the left [clavicle](https://durgical.com/en/anatomy/clavicle/) or at the upper left sternal border
- Bounding pulses and a wide pulse pressure
- Fast breathing, poor feeding and poor weight gain with large shunts
- In preterm babies: worsening breathing or difficulty coming off the ventilator
- Often no symptoms when the duct is small

## Red flags

- Differential cyanosis (blue feet, pink hands), which suggests a reversed shunt
- Heart failure signs in an infant
- Sudden collapse of a newborn with a duct-dependent heart defect as the duct closes

## Diagnosis

**Clinical**
Continuous machinery murmur in the left infraclavicular area, bounding pulses and a wide pulse pressure.

**Tests**
ECG may show left ventricular hypertrophy with large shunts. Newborn pulse oximetry screening, comparing a hand and a foot, helps detect critical congenital heart disease.

**Imaging**
Echocardiography with Doppler confirms the duct, its size, the direction of flow and left heart enlargement. [Chest](https://durgical.com/en/anatomy/region/chest/) X-ray may show cardiomegaly and increased lung markings.

## Differential diagnosis

- Venous hum
- Coronary arteriovenous fistula
- Ruptured sinus of Valsalva aneurysm
- Aortopulmonary window
- Ventricular septal defect with aortic regurgitation

## Goal of treatment

Close a haemodynamically significant duct to prevent heart failure, pulmonary vascular disease and endarteritis, while keeping it open in newborns whose circulation depends on it.

## Treatment

**Follow-up**
Many ducts in preterm babies close on their own; teams give supportive care, adjust fluids and repeat echocardiography.

**Medical**
In preterm babies, cyclo-oxygenase inhibitors (NSAIDs) or, in some units, acetaminophen can promote closure; practice varies between centres.

**Procedure**
Transcatheter closure with a coil or occluder device is standard for most children and adults and is increasingly used in preterm babies.

**Surgical**
Surgical ligation or clipping when other methods fail or are unsuitable.

**Acute**
In duct-dependent defects, a prostaglandin E1 infusion keeps the duct open until surgery or a catheter procedure.

## Drugs for this condition

- [Indometacin](https://durgical.com/en/pharmacology/indometacin/)

## Complications

- Heart failure
- Pulmonary hypertension and Eisenmenger syndrome
- Infective endarteritis
- In preterm babies: associations with bronchopulmonary dysplasia, necrotising enterocolitis and intraventricular haemorrhage
- [Recurrent laryngeal nerve](https://durgical.com/en/anatomy/recurrent-laryngeal-nerve/) injury after surgical ligation

## Prognosis

After closure, life expectancy is normal. In preterm babies the outcome depends mostly on the degree of prematurity and its other problems.

## Prevention

- Rubella vaccination before pregnancy
- Good antenatal care to reduce preterm birth

## Test yourself

Think of the answer, then tap the question to see it.

## What murmur is classic for a patent ductus arteriosus?

A continuous machinery murmur below the left clavicle.

## Which drug class can close a patent ductus in a preterm baby?

Cyclo-oxygenase inhibitors (NSAIDs), which lower prostaglandin levels.

## Which drug keeps the ductus open in a duct-dependent heart defect?

Prostaglandin E1.

## What structure does the ductus arteriosus normally become?

The ligamentum arteriosum.

## Why does a reversed patent ductus cause cyanosis of the feet but not the hands?

Deoxygenated blood enters the aorta beyond the left subclavian artery, so it reaches mainly the lower body.

[Add to my cards (5)](https://durgical.app/estudiar/?add=/en/conditions/patent-ductus-arteriosus/)

## Related conditions

- [Ventricular septal defect](https://durgical.com/en/conditions/ventricular-septal-defect/)
- [Atrial septal defect](https://durgical.com/en/conditions/atrial-septal-defect/)
- [Coarctation of the aorta](https://durgical.com/en/conditions/coarctation-of-the-aorta/)
- [Tetralogy of Fallot](https://durgical.com/en/conditions/tetralogy-of-fallot/)
- [Heart failure](https://durgical.com/en/conditions/heart-failure/)
- [Infective endocarditis](https://durgical.com/en/conditions/infective-endocarditis/)
- [Aortic regurgitation](https://durgical.com/en/conditions/aortic-regurgitation/)

Educational information, not medical advice. For any symptom, see a health professional.

Sources: [Patent Ductus Arteriosus](https://www.ncbi.nlm.nih.gov/books/NBK430758/) (StatPearls (NCBI Bookshelf), 2023).

[← All conditions](https://durgical.com/en/conditions/)

## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake

Representative model, for educational purposes only.

---
Source: https://durgical.com/en/conditions/patent-ductus-arteriosus/
License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/conditions/patent-ductus-arteriosus/