Paeds cardio (ILA 3) Flashcards
Describe the circulation in the foetus
- umbilicus supplies oxygen to the foetus
- umbilical cord goes into liver and empties into portal vein
- portal vein -> IVC -> R atrium
- R atrium has higher pressure than L atrium as gets all the systemic venous return
- blood flows through foramen ovale across the atrial septum into L atrium
- L atrium blood flows into L ventricles and pumped to upper body
What is the role of the ductus arertiosus?
connects pulmonary artery to the aorta
What circulatory changes occur with the foetus’s first breath?
- resistance to pulmonary blood falls and volume of blood flowing through lungs increases -> rise in L atrial pressure
- foramen ovale closes
- ductus arteriosus closes within first few hours
Outline the possible causes of congenital heart disease?
MATERNAL DISORDERS - rubella, SLE, diabetes mellitus
MATERNAL DRUGS - warfarin, fetal alcohol syndrome
CHROMOSOMAL ABNORMALITY - downs syndrome, Edwards syndrome, Palau syndrome, Turners syndrome, Williams syndrome
Describe the 5 ways in which congenital heart disease presents?
- antenatal diagnosis
- heart murmur
- heart failure
- cyanosis
- shock
How are congenital heart defects detected in the foetus ?
fetal anomaly scan at 18-20 weeks gestation
checks anatomy of fetal heart
if abnormality detected, do a detailed fetal ECHO
How do “innocent murmurs” present?
4 S's... aSymptomatic Soft blowing murmur Systolic murmur only left Sternal edge
List the possible neonatal causes of heart failure?
neonatal heart failure is caused by obstructed systemic circulation
L->R shunts
severe coarction of the aorta
interruption of the aortic arch
hypoplastic L heart syndrome
List the possible infantile causes of heart failure?
heart failure in young children is caused by high pulmonary blood flow
VSD
atrioventricular septal defect
persistent ductus arteriosus
List the causes of heart failure in older children?
caused by right to left heart failure
Eisenmenger syndrome rheumatic heart disease cardiomyopathy myocarditis pericardial effusions
List the signs of left sided heart failure
breathlessness - on exertion, feeding sweating poor feeding recurrent chest infections palpitations
List the signs of right sided heart failure
ankle oedema
hepatomegaly
raised JVP
ascites
State the 3 types of cyanosis
- peripheral cyanosis
- central cyanosis
- persistent cyanosis
Describe peripheral cyanosis
“blue hands and feet”
occurs when a child is cold or unwell or with polycythaemia
Describe central cyanosis
“blue tongue”
haemoglobin in blood >50g/L
seen in bronchiolitis, sepsis, resp infection
How are congenital heart defects detected?
ECHOCARDIOGRAM
List the 3 left to right shunts causing breathlessness
- atrial septal defect
- ventricular septal defect
- patent ductus arteriosus
What is the most common atrial septal defect
secundum ASD in 80% = defect in centre of atrial septum involving foramen ovale
How does an atrial septal defect present?
asymptomatic
breathlessness
recurrent chest infections
What murmur is heard with an atrial septal defect?
ejection systolic murmur at L sternal edge
How is atrial septal defect managed?
if small - closes spontaneously
if large - surgical correction
How might a large ventricular septal defect present?
breathlessness
faltering growth
recurrent chest infectons
failure to thrive
Which murmur is heard with ventricular septal defect?
pan systolic murmur
heard loudest with a small VSD
softer with a larger VSD
List the signs on examination of a patient with a VSD
tachycardia tachypnoea pan systolic murmur apical mid diastolic murmur loud pulmonary second sound enlarged liver
Outline the findings on a chest x-ray of someone with a large VSD
cardiomegaly
enlarged pulmonary arteries
increased pulmonary vascular markings
pulmonary oedema
How is VSD managed?
small - close spontaneously
large - surgery at 3-6 months of age
What is patent ductus arteriosus?
when the ductus arteriosus fails to close by 1 month after expected date of delivery due to defect in the constrictor mechanism of the duct
Which murmur is heard in patent ductus arteriosus?
continuous murmur beneath the left clavicle
What are the signs of patent ductus arteriosus?
continuous murmur collapsing or bounding pulse pulmonary hypertension tachypnoea failure to thrive
How is patent ductus arteriosus diagnosed?
echo
How is patent ductus arteriosus managed?
NSAIDs e.g. indomethacin
surgical closure with coil/ occlusion device at 1 y/o
List the right to left shunts? “cyanotic”
- tetralogy of ballot
2. transposition of great arteries
which test is done to determine heart disease in a cyanosed neonate?
hyperoxia (nitrogen washout) test
infant placed in 100% oxygen for 10 mins and if right radial arterial press still low= cyanotic congenital heart disease
outline the management for a cyanosed neonate
- stabilise ABC
2. prostaglandin infusion - keeps duct open so blood can travel to lungs
What are the side effects of a prostaglandin infusion?
apnoea seizures flushing vasodilation hypotension
What are the 4 features of tetralogy of fallot?
- pulmonary stenosis
- right ventricular hypertrophy
- overriding of the aorta
- ventricular septal defect
how does tetralogy of fallot present?
severe cyanosis
hyper cyanotic events on exercise, crying, defacating
squatting on exercise
which murmur is heard with tetralogy of fallot?
loud ejection systolic murmur at left sternal edge
How are hyper cyanotic events managed?
usually self limiting but if >15 mins…
- pain relief
- IV propanol
- bicarbonate
- artificial ventilation
What are the causes of cyanotic heart disease? (5 T’s)
Tricuspid atresia Tetralogy of fallot Transposition of the great arteries Truncus arteriosus Total anomalous pulmonary venous connection
What is transposition of the great arteries?
pulmonary artery and aorta swap!!
aorta connected to right ventricle so blue blood returned to body
pulmonary artery connected to L ventricle so pink blood returned to lungs
How does transposition of the great arteries present?
CYANOSIS - on day 2 of life
no murmur
2nd heart sound loud
Which imaging is diagnostic for translation of the great arteries?
ECHO- shows abnormal connections
How is transposition of the great arteries managed?
- prostaglandin infusion
- balloon atrial septosomy
- surgery to switch arterial supply!! (surgery when around 6kg)
When does Eisenmengers syndrome occur?
it is the reversal of a left to right shunt
if not treated at an early age, the shunt causes pulmonary arteries to have thick walls and causes PULMONARY HYPERTENSION leading to R sided heart failure and death
What are the 2 common mixing CHD?
- atrioventricular septal defect
2. tricuspid atresia
Describe the presentation of atrioventricular septal defect
commonly associated with Downs syndrome
cyanosis at birth
heart failure at 2-3 weeks
pulmonary hypertension
Describe tricuspid atresia
obstructed tricuspid valve causing a right to left shunt
only the left ventricle is effective, the right ventricle is small and nonfunctional
How does tricuspid atresia present?
CYANOSIS!
How is tricuspid atresia managed?
aim is to maintain a secure supply of blood to the lungs at low pressure by…
- Blalock Traussig shunt insertion
- pulmonary artery banding operation
- Glenn and Fontan operation
List the 3 causes of outflow obstruction in the well child
- aortic stenosis
- pulmonary stenosis
- coarction of the aorta
What is aortic stenosis?
aortic valve leaflets are partly fused together so there is restrictive exit of the blood from the left ventricle
What are the symptoms of severe aortic stenosis?
- reduced exercise tolerance Causing SOB
- chest pain on exertion
- syncope
List the signs seen in aortic stenosis
carotid thrill
narrow pulse pressure
ejection systolic murmur
small rising pulse
How would you investigate aortic stenosis?
- Chest X-ray - Left ventricular hypertrophy with post-stenotic dilatation of the ascending aorta
- ECHO
What is pulmonary stenosis?
pulmonary valve leaflets partly fused together so there is restrictive exit from the right ventricle
List the signs of pulmonary stenosis
- ejection systolic murmur
- palpable thrill
- ejection click
- R ventricular heave
Describe the findings on investigations of pulmonary stenosis
- Chest radiography - normal or post stenotic dilatation of the pulmonary artery
- ECG- R ventricular hypertrophy
List the causes of outflow obstruction in the sick infant
- coarction of the aorta
- interruption of the aortic arch
- hypo plastic left heart syndrome
What is coarction of the aorta?
narrowing of the descending aorta - usually at the ductus arteriosus
What is coarction of the aorta associated with?
males
Turners syndrome
neurofibromatosis
bicuspid aortic valve
How does coarction of the aorta present?
- peripheral cyanosis, SOB
- systemic hypertension
- ejection systolic murmur
- radio-femoral delay
- intermittent claudication
How is coarction of the aorta investigated?
chest radiograph = rib notching, 3 sign
ECG= left ventricular hypertrophy
What are the symptoms and signs of supra ventricular tachycardia?
heart rate rapid: 250-300 beats/min
narrow complex tachycardia
ECG: T wave inversion
how is supra ventricular tachycardia managed in the severely ill child?
- circulatory and respiratory support
- vagal stimulating manoeuvres e.g. carotid sinus massage
- IV adenosine
What is the maintenance therapy for supra ventricular tachycardia?
flecainide or sotalol +/- propanol
What are the most common causative pathogens of infective endocarditis?
streptococcus viridian’s
Staph. aureus
Outline the risk factors of infective endocarditis
bad dental hygiene
prosthetic material in surgery
congenital heart disease
rheumatic valve disease
How does infective endocarditis present?
fever malaise anaemia splenomegaly splinter haemorrhages Janeway lesions clubbing retinal infarcts
How is infective endocarditis diagnosed?
- blood cultures
- ECHO - detect vegetations, fibrin and platelets
- raised ESR
How is infective endocarditis managed?
high dose IV penicillin + amino glycoside for 6 weeks
How is dilated cardiomyopathy managed?
ABCD A- ACE-inhibitors B- beta adrenoreceptor blocking agent C- carvedilol D- diuretics
List the causes of an ejection systolic murmur
innocent murmur coarction of the aorta aortic stenosis pulmonary stenosis tetralogy of fallot
List the causes of a pan systolic murmur
ventricular septal defect
tricuspid regurgitation
mitral regurgitation
List the causes of a continuous murmur
patent ductus arteriosus
collateral circulation
List the causes of a diastolic murmur
aortic regurgitation
mitral stenosis
tricuspid stenosis
