Congenital Heart Disease Flashcards
Atrial Septal Defects
- Increased pulmonary blood flow
- RV volume overload
- Pulmonary hypertension is rare
- Right heart failure
Acyanotic defects (left to right shunt)
- Atrial septal defect
- Ventricular septal defect
- Patent ductus arteriosus
- Aortic, pulmonary and mitral stenosis
- Coarctation of the aorta
- Atrio ventricular septal defects
Cyanotic defects (right to left shunt)
- Tetralogy of fallot
- Transposition of the great arteries
- Univentricular heart
- Total anomalous pulmonary venous drainage
- Hypoplastic left heart
- Tricuspid atresia
- Pulmonary atresia
Patent Ductus Arteriosus
Aorta and pulmonary arteries connected
Ventricular septal defects
- Left to right shunt
- LV volume overload
- Pulmonary venous congestion
- Eventual pulmonary hypertension
Atrio-ventricular septal defects
- Common in Down’s syndrome
- Atrial and ventricular shunts
Coarction
Narrowing around the aorta
Tetralogy of Fallot
- Pulmonary stenosis
- Ventricular septal defect
- Right ventricular hypertrophy
- Overriding aorta (aorta positioned over ventricular septal defect instead of left ventricle)
Transposition of the Great Arteries
- Right vent connected to aorta
- Left vent connected to pulmonary artery
- Not viable unless the two circuits communicate i.e. via atrial, ventricular or ductal shunts
- Example of bidirectional shunting
Hypoplastic Left Heart
- 20% to 30% won’t survive
- Left ventricle is underdeveloped
- Ascending aorta very small
- Right ventricle support system circulation
- Obligatory right to left shunt
Pulmonary Atresia
- No RV outlet
- R to L atrial shunt of entire venous return
- Blood flow to lungs via PDA
Univentricular heart
No septum
Tricuspid Atresia
- No RV inlet
- R to L atrial shunt of entire venous return
- Blood flow to lungs via VSD (or PDA)
Why do the abnormalities in Tetralogy of Fallot arise?
Ventricular septal defect - due to malalignment of the interventricular septum
Pulmonary stenosis - narrowing of the PV, due to an obstruction from the narrow right ventricular outflow region
Overriding aorta - aorta is attached over the VSD, so receives blood from both ventricles rather than just the left ventricle
Why is the patient cyanotic in the Tetralogy of Fallot?
- VSD and distal obstruction (pulmonary stenosis) which causes pressure in the RV to be higher than LV, blood is therefore shunted from right to left
- Deoxygenated and oxygenated blood get mixed due to overriding aorta
