Congenital Heart Disease Flashcards
What is atrial septal defect caused by?
Failure of the foramen ovale to close
Name the acyanotic defects
Atrial septal defect Patent foramen ovale Ventricular septal defect Patent ductus arteriosus Coarctation of the aorta
What happens to blood flow in ASD?
Blood flows from left to right atrium postnatally - no mixing of deoxygenated with oxygenated blood so is acyanotic
What causes patent foramen ovale?
Higher left atrial pressure causes closure of the flap valve in the atrial wall
What are effects if patent foramen ovale?
Generally clinically silent and may be present in 20% of population
May be the route by which a venous embolism reaches the systemic circulation if pressure on the right increases
Where does the ventricular septal defect commonly occur?
In the membranous portion of the interventricular septum
In which direction does blood flow in ventricular septal defect?
Left to right
What causes patent ductus arteriosus?
Failure of the ductus arteriosus to close after birth.
In utero, it is there for blood to flow from pulmonary artery to the aorta
Which direction does blood flow in PDA?
From aorta to pulmonary artery
What can PDA lead to?
Vascular remodelling of the pulmonary circulation and an increase in pulmonary resistance
What is Eisenmenger syndrome?
In PDA, if the pulmonary resistance increases to above that of the systemic circulation, the shunt will reverse direction and flow from the pulmonary artery to the aorta
What does the ductus arteriosus become after birth?
Ligamentum arteriosum
What causes coarctation of the aorta?
Narrowing of the aortic lumen in the region of the ligamentum arteriosum
What does coarctation of the aorta lead to?
Increased afterload in the left ventricle ➡️ left ventricular hypertrophy
Reduced blood flow to the rest of the body (except for head and neck)
Symptoms of coarctation of the aorta?
Weak and delayed femoral pulses
Upper body hypertension
When do symptoms of coarctation of the aorta normally occur?
If severe - shortly after birth
If mild - adult life
Name some cyanotic defects
Tetralogy of Fallot
Tricuspid atresia
Transposition of the great arteries
Hypoplastic left heart
What are the four anomalies of Tetralogy of Fallot?
Ventricular septal defect
Overriding aorta
Pulmonary stenosis
Right ventricular hypertrophy
What is overriding aorta?
When the aorta receives blood from both ventricles due to a ventricular septal defect.
Which direction does the blood flow in Tetralogy of Fallot?
Right to left shunt
What symptoms might affected individuals have in tetralogy of Fallot?
Cyanosis or spells of it during infancy
Mild cases can present in adulthood
What is tricuspid atresia?
Lack of development of the tricuspid valve
In tricuspid atresia, what must there be for blood to flow to the lungs?
Needs to be a complete right to left shunt of all blood returning to right atrium by an ASD or PFO and a VSD or PDA.
What is transposition of the great arteries?
Right ventricle is connected to aorta
Left ventricle connected to the pulmonary trunk.
Results in two unconnected parallel circulations
How is transposition of the heart arteries treated?
A shunt needs to be maintained or created immediately after birth until surgicalp correction can be made.
The ductus arteriosus can be maintained of an atrial septal defect formed.
What is a hypoplastic left heart?
When the left ventricle and descending aorta fail to develop properly. A PFO or ASD are also present. Blood supply to systemic circulation is via a PDA
What is cyanosis?
Abnormal blue discolouration of the skin and mucous membranes caused by an increase in deoxygenated haemoglobin.
