congenital heart defects

Question 1

how can congenital heart lesions be categorised

Answer 1

acyanotic or cyanotic

Question 2

what is cyanosis

Answer 2

blue-purple discoloration of the skin and mucous membranes caused by an elevated blood concentration of deoxygenated hemoglobin

Question 3

in which direction is the shunt in an acyanotic defect

Answer 3

left to right shunt.

flow from left to right

Question 4

in which direction is the shunt in a cyanotic defect

Answer 4

right to left shunt

Question 5

give some examples of acyanotic lesions

Answer 5

atrial septal defect 
ventricular septal defect 
Patent Ductus Arteriosus
Congenital Aortic Stenosis
Pulmonic Stenosis
Coarctation of the Aorta

Question 6

give some examples of cyanotic lesions

Answer 6

Tetralogy of Fallot

Transposition of the Great Arteries

Question 7

what is an atrial septal defect

Answer 7

a persistent opening in the interatrial septum after birth that allows direct communication between the left and right atria

Question 8

where is the most common site of ASD

Answer 8

most common site is at the region of the foramen ovale, termed an ostium secundum ASD

Question 9

what is a patent foramen ovale (PFO)

Answer 9

not a true ASD
the foramen ovale typically functionally closes in the days after birth, and it is permanently sealed by the age of 6 months through fusion of the atrial septa. A PFO remains when this fusion fails to occur.
clinically silent until the right atrial pressure becomes elevated (pulmonary hypertension or right-heart failure)
deoxygenated blood passes directly into the arterial circulation

Question 10

what are the consequences fo ASD

Answer 10

• oxygenated blood from the left atrium is shunted into the right atrium
• increased pulmonary blood flow
• RV vol overload , leading to enlargement of right side of heart
• pulmonary hypertension is rare
• eventual right heart failure

Question 11

what is a ventricular septal defect and where are they most commonly found

Answer 11

an abnormal opening in the interventricular septum

most often located in the membranous and muscular portions of the septum

Question 12

what are the haemodynamic effects of ventricular septal defects

Answer 12

• left to right shunt
• LV volume overload
• pulmonary venous congestion
• eventual pulmonary hypertension

Question 13

what is Patent Ductus Arteriosus

Answer 13

The ductus arteriosus is the vessel that connects the pulmonary artery to the descending aorta during fetal life. PDA results when the ductus fails to close after birth, resulting in a persistent connection between the great vessels

Question 14

what are the consequences of Patent Ductus Arteriosus

Answer 14

Prenatally, when the pulmonary vascular resistance is high, blood is diverted away from the immature lungs to the aorta. As the pulmonary resistance drops postnatally, the shunt reverses direction, and blood flows from the aorta into the pulmonary circulation instead. Because of this left-to-right shunt, the pulmonary circulation, left atrium, and LV become volume overloaded. This can lead to left ventricular dilatation and left-sided heart failure

Question 15

what is Congenital Aortic Stenosis

Answer 15

when the aortic valve has bicuspid leaf structure instead of three-leaflet configuration

Question 16

what are the consequences of Congenital Aortic Stenosis

Answer 16

the valvular opening has narrowed so left ventricular systolic pressure must increase to pump blood across the valve into the aorta.
LV hypertrophies
The high-velocity jet of blood that passes through the stenotic valve may damage the aortic wall and contribute to dilatation of that vessel.

Question 17

what is Pulmonic Stenosis

Answer 17

Obstruction to right ventricular outflow due to stenosis of pulmonary valve

Question 18

what is the consequence of pulmonary stenosis

Answer 18

right ventricular outflow, which leads to increased RV pressures and chamber hypertrophy

Question 19

what is Coarctation of the Aorta and what are the effects

Answer 19

discrete narrowing of the aortic lumen
the LV faces an increased afterload
development of left ventricular hypertrophy

Question 20

what is the Tetralogy of Fallot

Answer 20

1) a VSD caused by anterior malalignment of the interventricular septum
2) pulmonary stenosis
3) right ventricular hypertrophy
4) overriding aorta

Question 21

what happens in transposition of great arteries

Answer 21

1)RV is connected to aorta
2)LV is connected to pulmonary artery
this is not viable
this is a =n example of bidirectional shunting

Question 22

what happens in hypoplastic left heart syndrome

Answer 22

1) left ventricle is underdeveloped
2) ascending aorta very small
3) right ventricle supports systemic circulation
4) obligatory right to left shunt

Question 23

what is pulmonary atresia

Answer 23

the pulmonary valve doesn’t develop properly, preventing it from opening. Blood can’t flow from the right ventricle to the lung
blood flow to lungs via Patent ductus arteriosus

Question 24

what is tricuspid atresia

Answer 24

lack of development of tricuspid valve leaving no inlet to the right ventricle.