CVS Session 3- Congenital Heart Disease Flashcards
What are three categories of causes of CHD?
- genetic
- environmental
- conditions
What is the frequency of CHD?
6-8 CHD per 1000 live births
What is an Acyanotic defect?
One that doesn’t cause a lower than normal oxygen concentration in the blood.
Name the 5 Acyanotic defects.
- ASD
- VSD
- patent ductus arteriosus
- patent foreamen ovale
- coarctation of the aorta
What is an ASD? What are the consequences?
It is an abnormal opening in the septum between the two atria that persists after birth.
Because the L pressure > R pressure, therefore is a L to R shunt of blood. This causes increased pulmonary blood flow.
What is a VSD? What are the consequences?
An abnormal opening in the interventricular septum.
The pressure in the LV is > RV, therefore there is a L to R shunt of blood.
What is the most common part of the interventricular septum to cause a VSD?
Membranous part
What is a patent foreamen ovale? What are the consequences?
It is not a true ASD. It may be present in 20% of the population but be clinically silent.
It may be the route of a venous embolism into the systemic circulation if the RA pressure increases even slightly higher than the LA.
What is patent ductus arteriosus? What are the consequences?
It is when the ductus arteriosus between the aorta and pulmonary artery doesn’t close after birth.
Causes a shunt of blood from the aorta to the pulmonary artery.
What is coarctation of the aorta? What are the consequences?
It is when the aortic lumen is narrowed in the ligamentum arteriosum Region.
It causes an increased after load on the LV, causing it to hypertrophy.
Vessels to the head and neck are proximal to the defect, therefore their blood supply is normal. Blood supply to the rest of the body, however, is reduced.
Present with upper body hypertension and delayed, weak femoral pulses.
What are cyanotic defects?
Defects that cause a lower than normal oxygen saturation of blood.
Name the 4 cyanotic defects.
- Tetralogy of Fallot
- Tricuspid Atresia
- Transposition of the great arteries
- Hypoplastic Left heart
What is Tetralogy of Fallot? What are the consequences?
It is a group of four lesions arising from one developmental defect that places the outflow of the interventricular septum too far anteriorly and cephaladly. The four abnormalities: VSD, overriding aorta, pulmonary stenosis and RV hypertrophy.
Pulmonary stenosis causes RV hypertrophy because the RV has to work harder to push blood into the pulmonary artery.
Increased R pressure, VSD and overriding aorta cause a R to L shunting and therefore oxy and deoxygenated blood to mix.
What is tricuspid atresia? What are the consequences?
It is a lack of development of the tricuspid valve which means that blood from the RA doesn’t go into the RV. There must therefore be a complete R to L shunt.
What is transposition of the great arteries? What are the consequences?
When there are two unconnected, parallel blood supplies because the aorta has connected to the RV, and the pulmonary artery to the LV.
Means that reoxygenated blood from the lungs is returned to the lungs.
