The remnant of the ductus arteriosus is known as?

Appeared in: NORCET-7 Mains-2024

Explanation

The ductus arteriosus is a fetal vascular shunt that connects the pulmonary artery to the aorta.
Its primary function is to divert blood away from the non-functional fetal lungs directly into the systemic circulation.
After birth, hormonal changes and increased oxygen tension cause this vessel to close and transform into a fibrous cord known as the ligamentum arteriosum.

Option B: The ligamentum teres (or ligamentum teres hepatis) is the fibrous remnant of the fetal umbilical vein, not the ductus arteriosus.
Option C: The ligamentum venosum is the fibrous remnant of the fetal ductus venosus, which shunted blood past the liver.
Option D: The fossa ovalis is a depression in the interatrial septum of the adult heart, marking the location of the foramen ovale, a fetal opening between the right and left atria.

Visual 1: Diagram - A flowchart illustrating fetal circulation, highlighting the path of blood through the ductus arteriosus, foramen ovale, and ductus venosus.
Visual 2: Anatomical Illustration - A comparison of the fetal heart and the adult heart, clearly labeling the fetal structures and their corresponding adult remnants (e.g., ductus arteriosus vs. ligamentum arteriosum).

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Fetal circulation and postnatal anatomical remnants as background academic context rather than a clinical decision trigger.
A key clinical condition related to this concept is Patent Ductus Arteriosus (PDA), where the ductus arteriosus fails to close after birth.
Nurses assessing newborns should be vigilant for signs of PDA, such as a continuous 'machine-like' murmur, bounding pulses, and signs of respiratory distress or heart failure.
What if? If a preterm infant develops respiratory distress and has a prominent murmur, the nurse's priority is to notify the physician, as this population is at higher risk for a symptomatic PDA that may require medical (e.g., indomethacin) or surgical intervention.

How to Approach the Question

This is a factual recall question testing knowledge of anatomy and physiology.
First, identify the key anatomical structure mentioned in the question stem: 'ductus arteriosus'.
Next, recall the function of this structure in the context of fetal circulation (shunting blood away from the lungs).
Access your knowledge of the circulatory changes that occur after birth.
Match the fetal structure (ductus arteriosus) with its corresponding adult remnant (ligamentum arteriosum).
Review the other options to confirm they are remnants of different fetal structures (umbilical vein, ductus venosus, foramen ovale) to ensure your answer is the most accurate.

Concept Tested & Keywords

QbEFVwZHRSvZU8LhX_QZDz

Practise the full NORCET-7 Mains-2024

Attempt every question from this paper in a timed mock, then review the full solution for each one.