QuestionSBA
QuestionChoice
This is the cause of a patent ductus arteriosus, which forms a shunt between the aorta and the pulmonary trunk. It does not cause the development of a VSD.
10007784
e
Failure of the ductus arteriosus to close at birth
QuestionChoice
The ostium secundum is present in the embryology of the inter-atrial septum (the septum between the right and left atria). If it is too large within the septum primum, it can result in an atrial septal defect. It does not cause the development of a VSD.
10007782
c
Ostium secundum defect with an abnormally large opening
QuestionChoice
Atherosclerotic damage occurs as a result of plaque build-up over the lifespan. It is not a cause of congenital heart defects in a developing foetus. It is not a cause of a VSD.
10007781
b
Atherosclerotic damage to the interventricular septum
QuestionChoice
This occurs in a AVSD - atrioventricular septal defect. It does not cause the development of a VSD.
10007783
d
Failure of the endocardial cushions to develop properly
QuestionChoice
The foetus has a congenital heart defect responsible for the flow of oxygenated blood from the left ventricle to the right ventricle. This is due to a VSD (ventricular septal defect). You may recall from embryology of the heart that the muscular portion of the interventricular septum grows cranially from the base of the heart tissue towards the endocardial cushions. Then, the membranous portion grows caudally from the endocardial cushions to close the primary interventricular foramen. In a VSD, the membranous portion of the interventricular septum is most likely to fail in development.
10007780
a
Membranous portion of the interventricular septum fails to develop
Concept
Chapter
2693
4099
Congenital malformations of the heart
Topic
171
Embryology
14103
A 28-year-old pregnant woman visits the antenatal clinic for a third trimester review. A ventricular septal defect (VSD) is detected, presenting as a shunt between the left and right ventricles. The process of developing this heart defect is due to the failure in part of an embryological process during pregnancy.

Which of the following embryological processes is likely to have resulted in this defect?
a