Lecture 3 - Congenital Heart Disease

Question 1

what causes murmurs at rest?

Answer 1

disturbed flow

Question 2

what causes tetralogy of fallot?

Answer 2

single developmental defect placing the outflow portion of the iv septum too far in the anterior and cephalad directions

Question 3

what is an acyanotic defect?

Answer 3

doesn’t result in lower than normal concentration of oxygen in the blood

Question 4

what is an atrial septal defect?

Answer 4

opening in the septum between the two atria that persists following birth

Question 5

what is the purpose of the foramen ovale?

Answer 5

allows right to left shunting of oxygenated blood before birth

Question 6

why is an ostium secundum asd (at the foramen ovale) acyanotic?

Answer 6

left atrial pressure is higher than right atrial pressure so flow will mostly be left to right, so there’ll be no deoxy blood mixing with oxy blood being pumped around the circulation

Question 7

what is a patent foramen ovale?

Answer 7

foramen ovale doesn’t close

generally clinically silent because higher left atrial pressure causes functional closure of the flap valve

Question 8

what is the clinical consequence of a pfo?

Answer 8

may allow a route for a venous embolism to reach the systemic embolism if right pressure increases

Question 9

what is a ventricular septal defect?

Answer 9

opening in the iv septum, mostly in the membranous portionbecause left ventricular pressure is higher than right, allows left to right blood flow

Question 10

what is the role of the ductus arteriosus?

Answer 10

shunts blood from the pulmonary artery to the aorta before the lungs are functioning

Question 11

what is a patent ductus arteriosus?

Answer 11

the ductus arteriosus doesn’t close

allows blood flow from aorta to pulmonary artery

Question 12

what is the result of chronic left to right shunting?

Answer 12

vascular remodelling of the pulmonary circulation

increase in pulmonary resistance

Question 13

what is eisenmenger syndrome?

Answer 13

resistance of pulmonary circulation increases above systemic
shunt reverses direction as pressure on the right side increases
result of vsd

Question 14

what is coarction of the aorta?

Answer 14

narrowing of aortic lumen in the region of the ligamentum arteriosum

Question 15

what is the result of a narrowed aorta?

Answer 15

increased afterload on the left ventricle
left ventricular hypertrophy
reduces blood flow to the body

Question 16

what four conditions come under the tetralogy of fallot?

Answer 16

vsd
overriding aorta
pulmonary stenosis
right ventricular hypertrophy

Question 17

how does pulmonary stenosis causes rv hypertrophy?

Answer 17

rv must operate at higher pressure to pump blood through the pulmonary artery

Question 18

how does tetralogy of fallot cause cyanosis?

Answer 18

increased right side pressure, vsd and overriding aorta allow right to left shunting so deoxy blood mixes with the oxy blood being pumped round the circulation

Question 19

what is tricuspid atresia?

Answer 19

lack of development of tricuspid valve so there is no inlet to rv
complete right to left shunt of all blood returning to ra (by asd or pfo)v
sd or pda allows blood flow to lungs

Question 20

what is transposition of the great vessels?

Answer 20

two unconnected parallel circulations rather than two in series
rv connected to aorta and lv to pulmonary trunk
not compatible with life after birth unless a shunt exists to allow the two circulations to communicate

Question 21

what is hypoplastic left heart?

Answer 21

lv and ascending aorta fail to develop properly
pfo or asd are also present
blood supply is via a pda
lethal without surgical correction