Congenital Heart Disease Flashcards
When is the critical time for heart development?
3-6 weeks
What are some causes of congenital heart defects?
Family history Prematurity Genetics Environment Multifactorial/Unknown Alcohol exposure Infections Medications Maternal conditions
What is the most common type of congenital heart defect?
VSD
What is the first branch of the aorta?
Coronary arteries
What is the common heart defect from Down’s?
Atrioventricular septal defect
Gives a common AV valve
Size of appendages in LA vs RA
RA = large appendage LV = small apppendage
What does
- Situs
- Solitus
- Inversus
- Isomerism
- Position or location in body
- Normal
- Inversus
- Mixed up
4 causes of pump malfunction
Muscle of the pump is defective
Inadequate filling of the pump
Too much fluid to pump
Too much resistance to output
Reasons for muscle pump being defective
Most common intrinsic muscle disease (myocyte, storage, metabolic)
Abnormal coronary supply (ischemia)
Reasons for pump inadequately filling
Pericardial restriction (fluid or fibrosis) Muscle restriction Obstruction of venous return (systemic or pulmonic)
Reasons for too much fluid to pump (excessive preload)
Left to right shunt
Regurgitant valve lesions
Reasons for excessive resistance (increased afterload)
Left side: could be due to aorta, aortic valve, sub-aortic shelf, left heart
Right side: could be due to pulmonary valve, obstruction
How can a fetal diagnosis be made?
Recognized on ultrasound
Allows you to get a good picture of the 4 chambers of the heart as long as fetus is positioned well
3 diagnoses we can make prenatally
Heart rate and rhythm block (congenital heart block or tachyarrhythmia)
Hydrops fetalis (edema of whole body)
Structure abnormality
When is the fetal anomaly screen?
18-20 weeks
How does fetal circulation work
Pumped into aorta Through systemic circulation Oxygen is picked up from the placenta Oxygenated blood enters RA Through foramen ovale Into LA Into LV Out into aorta
Transitional circulation
Once baby begins to breath
Equal L and R ventricular pressure
Still have a patent ductus arteriosus and foramen ovale (close within a couple of days)
Critical heart disease
Requires appropriate intervention within the first month for optimal outcome
Typically the lesions are duct-dependent
May be masked by transitional circulation
Beware early hospital discharge
What screen should every newborn get?
Pulse oximetry screening
Enhances teh detection of critical congenital heart disease
What is the classification for cyanosis? When can you see it?
Technically under 95%
See it under 85%
5 presentations in the newborn
Cyanotic CHD R-L shunt Complex mixing Transposition Heart failure complex
4 defects in the tetralogy of Fallot
VSD (membranous part)
Pulmonary stenosis
Dextroposition of the aorta (moved to the right and overrides the septum, so gets blood from RV and LV)
RV hypertrophy (compensatory)
Babies with tetralogy of Fallot present with…
Cyanosis
Because PA is narrow, less blood enters lungs to be oxygenated
RV attempts to overcome resistance and hypertrophies, but ends up pumping blood through VSD into LV
Mixing of oxygenated and deoxygenated blood in the aorta
Need a surgical repair
How can you survive a transposition?
If you have an open ASD
Mixing must occur to allow some oxygenated blood to go to the systemic circulation
Will have really low O2 sats
Coarctation
Narrowing of the aorta
Innocent murmur is recognized by (6)
Sternal location Systolic timing Stays sternal Short duration Soft intensity Sounds are normal
What is the resp rate in a child to be worried about?
60 breaths/min
Normal is about 45-50
What medications do you not give to children for CHD?
Prostaglandins
