Paediatrics - cardiology Flashcards
Where do the umbilical arteries run between?
Internal iliac arteries and placenta - there are two of them
Where does the umbilical vein run between?
Placenta and portal vein
Where does the ductus venosus run between?
Umbilical vein and inferior vena cava to bypass the liver
Where does the ductus arteriosis connect?
Pulmonary artery and aorta - shunt blood from pulmonary artery
Does the umbilical arteries carry O2 or not?
No they are deoxygenated
Does the umbilical vein carry O2 or not?
Yes they are oxygenated by placenta
How does the foramen ovale close?
Alveoli open with first breath –> pulmonary BP decreases –> right atrium pressure decreases –> left atrium pushes foramen ovale inward (like a closing valve)
How does the ductus arteriosis close?
Prostaglandins needed to keep ductus arteriosis open –> oxygenated blood causes drop in prostaglandins –> ductus arteriosis closes after a few days
What are some examples of non-cyanotic congenital heart disease (most to least common) (6)?
- VSD
- Patent ductus arteriosus
- ASD
- Pulmonary stenosis
- Aortic stenosis
- Coarctation of the aorta
What is the most common form of heart defect?
Ventricular septal defect
What is the pathophysiology of the movement of blood around the heart in a ventricular septal defect?
Blood is shunted from the left to the right
What happens as a result of left to right shunting of blood in a VSD?
Pulmonary hypertension can occur
What can happen as a result of a severe VSD?
Eisenmenger syndrome - pulmonary pressure increases to more than systemic pressure and the shunt reverses from left to right and becomes right to left
What will happen to the patient as a result of eisenmenger syndrome?
They will become cyanotic
What are symptoms of a VSD (4)?
- Tachypnoea
- Dyspnoea
- Poor feeding
- Failure to thrive
however often symptomless
When are VSD usually picked up + what sort of murmur (2)?
- Sometimes visible on antenatal scanning
- Ascultation - pansystolic murmur at lower left sternal border
What are some risk factors for VSD (6)?
- Fam history
- Genetic conditions e.g. Downs, Edwards, Pataus
- Smoking
- Maternal diabetes
- Maternal rubella
- Prematurity
How are VSDs treated (2)?
- Small = left alone and monitored
- Medication e.g. ACE-i + diuretics, open heart surgery, transvenous catheter closure
What are some complications of VSD (2)?
- Heart failure
- Endocarditis
What is the flow of blood around the heart in a patient with an atrial septal defect?
Shunting of blood from left to right atria
What complication of ASD can occur and how would the patient present?
Eisenmenger syndrome - patient would be cyanotic
What are the symptoms of an ASD (4)?
- Tachy/dyspnoea
- Poor weight gain
- Recurrent chest infections
- Difficulty feeding
often asymptomatic however
What would be heard on auscultation of those with ASD (2)?
- Soft, systolic ejection murmur
- Fixed split S2
these are due to more blood being forced through pulm valve
What are some complication of ASD (3)?
- Stroke (from DVT)
- AF
- Pulmonary hypertension
How are ASDs managed (3)?
- Watch and wait if small
- Blood thinners (in adults) to prevent stroke
- Catheter/ surgical repaire
What two other septal defects can occur (other than ASD and VSD)?
- Patent foramen ovale (although not strictly a steal defect)
- Atrio-ventricular septal defect
How would a patent ductus arteriosis present (4)?
Same as an ASD
* Poor feeding
* Recurrent LRTI
* Tachy/dyspnoea
* Poor weight gain
What would a patent ductus arteriosis sound like?
Continuous machinery murmur
How is patent ductus arteriosis managed?
- Medications e.g. ibuprofen to inhibit prostaglandins
- Surgical catheter repair if not closed by age 1
What is congenital pulmonary stenosis?
Pulmonary valve is malformed and has a narrow opening between the right ventricle and pulmonary artery
What does pulmonary stenosis sound like upon auscultation?
Ejection systolic murmur @ 2nd intercostal, left sternal border
What does aortic stenosis sound like?
Ejection systolic murmur @ second intercostal right sternal border
How do congenital pulmonary and aortic stenosis present?
Often asymptomatic, but similar to in adults
What is coarctation of the aorta?
Narrowing of the aorta, usually around the ductus arteriosis
What genetic syndrome is coarctation of the aorta often associated with?
Turners syndrome
What are signs/ symptoms of coarctation of the aorta (5)?
- Week femoral pulse
- Ejection systolic murmur
- Tachypnoea
- Poor feeding
- Grey and floppy baby
What signs/ symptoms of coruscation of the aorta may show with development (2)?
- Underdevelopment of legs/ left arm
- Left ventricular heave
How is coruscation of aorta treated (2)?
- Surgery
- Prostaglandin E can be used to keep the ductus arteriosus open
What are some causes of cyanotic congenital heart disease (3)?
- Tetralogy of Fallot
- Transposition of the great arteries
- Complete AVSD = less common
What is transposition of the great arteries?
The aorta and pulmonary artery have switched place - so the aorta connects to right ventricle and pulmonary artery connects to left ventricle. This effectively creates a separate pulmonary and systemic circulation.
What are some risk factors for these cyanotic congenital heart diseases (4)?
- Rubella infection
- Increased maternal age
- Diabetic mother
- Alcohol consumption
How does transposition of the great arteries present (2)?
- Sometimes picked up antenatally
- Cyanotic baby within first day (after ovale and ductus arteriosus close)
How is transposition of the great arteries treated?
- Prostaglandin E infusion (maintains ductus arteriosus)
- Surgery “artery switch”
What is tetralogy of Fallot?
- VSD
- Pulmonary valve stenosis
- Right ventricular hypertrophy
- Overriding aorta (aorta positioned over VSD)
How are most cases of tetralogy of Fallot diagnosed?
Antenatal scans
What is it known as when a child with tetralogy of Fallot becomes cyanotic for a brief period?
Tet spell
What causes a tet spell?
Decrease in systemic circulation resistance / increase in pulmonary circulation resistance e.g. exertion –> increase in CO2 which reduces systemic circulation resistance
How are congenital heart diseases investigated?
- Echo
however some picked up through antenatal scanning
What causes heart failure in children (6)?
- Congenital heart diseases
- Cardiomyopathies
- Arrhythmias
- Anaemia
- Infective endocarditis
- Rheumatic fever
What are the 3 main types of cardiomyopathy that may affect children?
- Dilated
- Restrictive
- Hypertrophic
What arrhythmias are common in children (3)?
- Supraventricular tachycardia
- Congenital heart block
- Long QT syndrome
What causes supraventricular tachycardia in children?
- AV nodal re-entrant tachycardia
- AV re-entrant tachycardia
- Atrial tachycardia
How does atrial tachycardia cause SVT?
Electrical signals originate in the atria somewhere other than the SA node and cause a faster heartbeat (the cause of the fast heart rate has originated in the atria)
What is AV re-entrant tachycardia known as?
Wolf Parkinson’s white syndrome
What is the re-entry point in WPW known as?
Bundle of Kent
What are the symptoms of SVT (6)?
- Palpitations
- Syncope
- Dizziness
- SOB
- Sweating
- Weekness
How is acute SVT managed in cases without life threatening features (4)?
- Vagal manoeuvres
- Adenosine
- Verapamil/ beta blocker
- Synchronised DC cardioversion
What are some life threatening features of SVT (4)?
- Chest pain (cardiac ischemia)
- LOC
- Shock
- Severe symptoms
What vagal manoeuvres would be used to treat SVT initially (3)?
- Valsalva manoeuvre (blow against resistance)
- Carotid sinus massage
- Diving reflex (face in cold water)
How do vagal manoeuvres slow heart rate?
Stimulate vagus nerve (PSNS)
What is the longer term management of recurrent SVT (2)?
- Radiofrequency ablation
- Long term medication
How do CCBs (adenosine and verapamil) and beta blockers treat SVT?
Slow down conduction through AV node
Anatomically, what causes congenital heart block?
Underdevelopment/ malformation of the AV node
What condition in the mother is associated with complete congenital heart block?
Sjogrens syndrome/ SLE
What causes congenital heart block in those whose mother has Sjogrens/ SLE?
Anti-ro and Anti-la antibodies cross the placenta and cause atrophy/ fibrosis of AV node
What might cause long-QT syndrome in children (2)?
- Inherited channelopathies
- Other similar causes to adults e.g. electrolyte imbalances, medications
How might long-QT present in children (2)?
- Usually during later childhood
- LOC during exercise/ intense emotion
however often symptomless
What could long-QT be mistaken as in childhood?
Epilepsy (due to LOC)
What is rheumatic fever?
Autoimmune condition affecting multiple systems throughout the body
What bacteria causes rheumatic fever?
Group A strep (strep pyogenes)
What is the mechanism by which the body attacks itself in rheumatic fever?
The antibodies on strep pyogenes are very similar to those found in the body, such as those in the myocardium, so the body ends up mistakenly attacking itself
What type hypersensitivity is rheumatic fever?
Type 2
What are the symptoms/ presentation of rheumatic fever (6)?
- FEVER
- Joint pain
- Rash
- SOB
- Chorea
- Skin nodules
- 2-4 weeks post viral infected - ‘strep throat’
Which joints are typically affected in rheumatic fever?
Larger joints
How is the skin affected in rheumatic fever (2)?
- Subcutaneous nodules (often over elbows/ extensor surfaces)
- Erythema marginatum
What valve is commonly affected by rheumatic fever?
MITRAL valve
How is rheumatic fever investigated (3)?
- Throat swab (bacterial culture)
- Anistreptolysin (ASO) antibody titre
- ECG/ CXR/ echo
What criteria can be used to diagnose rheumatic fever?
Jones criteria
How should rheumatic fever be managed (2)?
- NSAIDs
- Aspirin (for carditis)
What should be given to patients as prophylaxis follow rheumatic fever?
IM benzathine benzylpenicillin
What can be done to prevent rheumatic fever from occurring in the first place?
Prompt treatment of strep infections with phenoxymythylpenicillin (penicillin V)
What is a common cause of infective endocarditis in children?
Congenital heart disease - causing turbulent flow of blood
What are the symptoms of infective endocarditis (5)?
- Fever
- Fatigue
- Night sweats
- Muscle aches
- Anorexia
What are some examination signs of IE (7)?
- New murmur
- Splinter haemorrhages
- Osler nodes
- Janeway lesions
- Roth spots
- Petechiae
- Finger clubbing (if longstanding)
What are the 2 most common bacteria in children with IE?
- Strep viridians
- Staph aureus
What criteria is used to diagnose IE?
Dukes criteria
How is IE treated?
Broad spectrum Abx (amoxicillin + gentamicin)
should be based on blood cultures
