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Question 1

Congenital Heart Defects Caused by

Answer 1

genetic abnormalities,
rubella virus
environmental factors.

Question 2

the common atrium is divides into

Answer 2

right & left halves.

Question 3

Septum Primum shape

Answer 3

crescent-shaped membrane

Question 4

Septum Primum grows from

towards

Answer 4

the roof of the primordial atrium towards the fusing endocardial cushions.

Question 5

foramen primum

Answer 5

Septum primum grows toward endocardial cushions, and creates a small opening

Question 6

foramen primum serves as

Answer 6

shunt, enabling the oxygenated blood to pass from right atrium to left atrium

Question 7

foramen primum. become

Answer 7

smaller and disappears as the septum primum fuses completely with endocardial cushions to form the interatrial septum.

Question 8

foramen secundum

Answer 8

opening formed by resorption of The upper part of septum primum that is attached to the roof of the common
atrium

Question 9

septum secundum.

Answer 9

Another septum descends on the right side of the septum primum

Question 10

septum secundum forms

Answer 10

an incomplete partition between the two atria → valvular foramen forms, (foramen ovale)

Question 11

Fate of site of foramen Ovale

Answer 11

site is represented by the Fossa

Ovalis.

Question 12

floor of the fossa ovalis

Answer 12

The septum primum

Question 13

margin of the fossa ovalis

Answer 13

The septum secondum

Question 14

margin of the fossa ovalis is

called

Answer 14

the limbus ovalis or (annulus)

ovalis.

Question 15

Fate of foramen Ovale

Answer 15

At birth when the lungs inflated and 
pulmonary circulation begins, the 
pressure in the left atrium increases 
and exceeds that of the right atrium.
• So the two septae oppose each 
other.

Question 16

Atrial Septal Defects (ASD) More frequent in

Answer 16

females

Question 17

Common atrium Resulting from

Answer 17

complete failure of the septum primum and septum secundum to form.
failure of both septa to develop.

Question 18

Sinus venosus ASDs are located in

Answer 18

the superior part of the interatrial septum,

close to the entry of the SVC

Question 19

Sinus venosus ASDs result from

Answer 19

incomplete absorption of the sinus venosus into the right atrium, abnormal development of the septum secundum, or both.

Question 20

Most common form of Atrial Septal Defects (ASD)

Answer 20

patent foramen ovale

Question 21

patent foramen ovale due to

Answer 21

incomplete adhesion between septum primum & secundum).

Question 22

Ostium secundum defect due to

Answer 22

defect in one or both septa.

septum primum and/or septum secundum.

Question 23

Endocardial cushions defects with ostium primum

Answer 23

septum primum does not fuse with cushions resulting in a patent
foramen primum
2.a cleft in the anterior cusp of the mitral valve

Question 24

types of ASD

Answer 24

Ostium secundum defect
Endocardial cushions defects with ostium primum
Sinus venosus defect
Common atrium

Question 25

Treatment of ASD

Answer 25

If it dose not close by age 2-5 years, then:
Cardiac Catheterization
Surgery

Question 26

Ostium Secundum ASDs Caused by

Answer 26

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