Cardiology Flashcards
What is the ductus arteriosus?
Connects the pulmonary artery to the aorta so that blood doesn’t flow to the lungs, closes within first few hours or days
What % of congenital heart defects are picked up antenatally? And when?
70% at 18-20 week anomaly scan
What is the most common presentation of congenital heart disease - complication of presentation?
A heart murmur - however 30% of children will have an innocent murmur at some point which is present in a normal heart
What are the hallmarks of an innocent ejection murmur?
4 s's aSymptomatic patient Soft blowing murmur Systolic murmur only - not diastolic left Sternal edge - no radiation Also - normal heart sounds with no added sounds and no parasternal thrill
What can be causes of innocent murmur
Anaemia or febrile illness due to increased cardiac output
Main cause of heart failure in first week of life
Coarctation of the aorta
What can be important in maintaining arterial perfusion in coarctation of the aorta
Right to left flow of blood via the arterial duct = duct dependant systemic circulation
If the duct closes then severe acidosis, collapse and death
Main cause of heart failure after first week of life - mechanism and symptoms (when?)
Left to right shunt. As weeks go on, pulmonary vascular resistance falls, progressive increase in left to right shunt and increase pulmonary blood flow
Causes pulmonary oedema and breathlessness - about 3 months of life
What will happen if left to right shunt goes untreated
Children will develop Eisenmenger syndrome - irreversibly raised pulmonary vascular resistance as resistance rises in response to the left right shunt
Shunt is now from right to left due to raised pulmonary pressure and TEENAGER is blue
Treatment of Eisenmenger syndrome
Only really heart lung transplant - medication is available to palliate symptoms
Causes of neonatal heart failure other than coarctation of the aorta x3
Hypoplastic left heart syndrome
Critical aortic valve stenosis
Interruption of the aortic arch
Causes of heart failure in infants
Due to high pulmonary flow therefore ventricular septal defect, atrioventricular septal defect and large persistent ductus arteriosus
Causes of heart failure in older children
Rheumatic heart disease and cardiomyopathy
When can peripheral cyanosis occur? X3
If child is cold, unwell from any cause or due to polycytheamia
When does central cyanosis occur? What level of reduction needs to be present for its identification
Due to fall in arterial blood oxygen tension
Can only be recognised if concentration of reduced haemoglobin in blood exceeds 5g/dl
Therefore less pronounced if child is anaemic
What is persistent cyanosis in an otherwise well child a sign of?
Structural heart disease
Presentation of right to left shunt symptom wise
Blue child
Presentation of left to right shunt symptom wise
Breathlessness or asymptomatic
3 causes of left to right shunt
ASD, VSD, or persistent ductus arteriosus
Two types of ASD and incidence
Secundum ASD (80%) Partial atrioventricular septal defect
What is Secundum ASD
Defect in centre of atria where foramen ovale is
What is partial AVSD?
Defect of AV septum involving atrial septum and av valves
Also 3 leaflet defect in left av valve with regurgitant leak
Symptoms of ASD
Asymptomatic or recurrent lung infections/wheeze
Arrhythmias from 4th decade onward
Physical signs of ASD on auscultation
Ejection systolic murmur best heard at left Sternal edge because increase blood flow over pulmonary valve
Physical sign of partial AVSD on auscultation
Apical pan systolic murmur due to regurgitation through AV valve
Signs of ASD and AVSD on chest X-ray x3
Cardiomegaly, increased pulmonary vascular markings, enlarged pulmonary arteries
ECG signs with Secundum ASD
Partial right bundle branch block is common
Right axis deviation due to right ventricle enlargement
ECG in partial AVSD
Superior QRS complex - mainly negative in avF - because defect is near av node therefore displaced node conducts to the ventricles superiorly
Management of Secundum ASD
Cardiac catheterisation with insertion of occlusion device usually done 3-5 years of age
Management of partial AVSD
Surgical correction. - usually done 3 years of age
What % of congenital heart disease is due to VSD
30%
Symptoms and signs of small VSD (what size?)
No symptoms and loud pan systolic murmur at lower left sternal edge (louder the murmur, smaller the defect)
Smaller than 3mm
Investigations in small VSD
Normal ecg normal X-ray - echo will show defect
Management of small VSD
They will close spontaneously
Symptoms of large VSD x4
Heart failure
Breathlessness and failure to thrive in 1 week old
Recurrent chest infections
Signs of large VSD x 5
Tachycardia, tachypnoea and enlarged liver from heart failure
Active precordium
Soft pansystolic murmur or no murmur
Apical mid-diastolic murmur (increased flow across mitral valve with return of blood through lungs)
Loud pulmonary second sound from raised pulmonary arterial pressure
Chest X-ray with large VSD
Cardiomegaly
Enlarged pulmonary arteries
Increased pulmonary vascular markings
Pulmonary oedema
What is the foramen ovale?
Hole between the right and left atrium. As the lungs are not in use, pressure in them is high and blood flow is low, therefore pressure is low in the left atria…also pressure in the right atria is high as it receives all the blood flow from the placenta. Therefore hole stays open. When lungs start breathing, blood flow to lungs increases and pressure in right atria drops as no more placenta therefore pressure higher in left atria and foramen closes
ECG in large VSD
Biventricular hypertrophy by 2 months of age
Management of large VSD
Treat heart failure with diuretics and captopril
Additional calorie intake
Surgery at 3-6months to prevent Eisenmenger syndrome
Two causes of patent ductus arteriosus
Congenital heart defect or prematurity (if in preterm infant)
Clinical features of patent ductus arteriosus with additional features if it’s a large duct
Continuous murmur upper left sternal edge (always a murmur because pressure is lower in the pulmonary artery than in the aorta throughout the cardiac cycle)
Pulse pressure increased causing a bounding or collapsing pulse
Large duct - heart failure and pulmonary hyper tension
Investigations in patent ductus arteriosus
X-ray and ECG usually normal
However if large the signs are the same as with large VSD
Management of patent ductus arteriosus
Closure with coil or occlusion device via cardiac catheterisation at 1 year of age
Occasionally surgical ligation
What sort of heart disease does right to left shunts cause
Cyanotic heart disease - present with cyanosis and O2 sats
Diagnostic test of cyanotic heart disease
Hyperoxia (nitrogen washout) test
Place infant in 100% oxygen for 10min - if right radial artery pao2 from blood gas remains low diagnosis can be made (if lung disease and persistent pulmonary hypertension of newborn have been excluded)
Management of neonatal cyanotic heart disease
Start prostaglandin infusion - maintain duct patency as they are duct dependant
What is most common cause of cyanotic heart disease and features x4
Tetralogy of fallot
- large VSD
- overriding aorta with respect to ventricular septum
- sub pulmonary stenosis causing right ventricular outflow tract obstruction
- right ventricular hypertrophy as a result
When are most tetralogy of fallot diagnosed?
Most are diagnosed antenatally or following identification of murmur in the first 2 months of life
Cyanosis may not be obvious at this stage - although a few present with severe cyanosis in first few days of life
Classical description of symptoms of tetralogy of fallot
Severe cyanosis
Hypercyanotic spells (irrability, crying, breathlessness and pallor) and squatting on exercise
Developing late in infancy
- now rarely seen in developed countries
Murmur in tetralogy of fallot
Loud harsh ejection systolic murmur at left Sternal edge from day 1 of life
With increasing outflow obstruction (due to muscular hypertrophy) murmur will shorten and cyanosis with increase
Chest X-ray in tetralogy of fallot
May have pulmonary artery ‘bay’ - concavity on left heart border where artery and outflow tract would normally be
Decreased pulmonary vascular markings
Management of tetralogy of fallot
Surgery to remove obstruction and close VSD at around 6 months of age
Very cyanosed infants may require shunt in the meantime eg. from subclavian artery to pulmonary artery
What does transposition of the great arteries cause
Right to left shunt
What is transposition of the arteries anatomically
Pulmonary artery is connected to the left ventricle and aorta to the right ventricle therefore oxygenated blood returns to the lungs and deoxygenated blood returns to the body
Unless there is a defect such as VSD, ASD or pda this is not compatible with life
Symptoms/presentation of transposition of the great arteries
Cyanosis - usually at 2 days of life when closure of pda leads to decreased mixing
Auscultation in transposition of great arteries
Usually no murmur but may be systolic murmur due to stenosis of left pulmonary outflow tract
Management of transposition of great arteries
Maintain ductus arteriosus - prostaglandin infusion
Balloon atrial septostomy may be life saving
Most need surgery - arterial switch procedure within first few days of life
- transected above the valves and switched over
Transfer coronary arteries over to new aorta
Which syndrome cause common mixing cardiac problems
Complete atrioventricular septal defect and complex congenital heart disease (such as mitral atresia, tricuspid atresia)
Breathless and blue
When is complete AVSD commonly seen?
Down’s syndrome
What are the defects present in complete AVSD
5 leaflet av valve - defect stretches all across the av junction and tends to leak
Which lesions cause outflow obstruction in a well child x3
Aortic stenosis, pulmonary stenosis, adult-type coarctation of the aorta
Features and symptoms of aortic stenosis
Can occur in association with mitral stenosis and coarctation of the aorta
Most have asymptomatic murmur but may present with chest pain on exertion, reduced exercise tolerance or syncope
Signs of aortic stenosis
Ejection systolic murmur - maximal at left Sternal edge and radiating to neck
Small volume, slow rising pulses
Apical ejection click
Features of pulmonary stenosis
Most are asymptomatic
Ejection systolic murmur best heard upper left Sternal edge
If severe might be right ventricular hypertrophy and heave
Features of adult-type coarctation of the aorta
Not duct dependant - gradually becomes more severe over many years
Features of coarctation of the aorta
Asymptomatic
Systemic hypertension in the right arm
Ejection systolic murmur at upper sternal edge
Collaterals heard with continuous murmur at the back
Radio femoral delay
Adult type coarctation of the aorta on X-ray
Rib notching - due to development of large intercostal arteries running under ribs to bypass obstruction
‘3’ sign with visible notch in the descending aorta at site of coarctation
Adult type coarctation of the aorta on ecg
Left ventricular hypertrophy
Causes of outflow obstruction in a sick child
Coarctation of the aorta
Interruption of the aortic arch
Hypoplastic left heart syndrome
How do sick children with outflow obstruction present?
Sick with heart failure and shock in neonatal period
Prostaglandin should be commenced straight away
When do children with coarctation of the aorta present?
Usually at 2 days of age with acute circulatory collapse when the da closes
Physical signs in children with coarctation of the aorta
Severe heart failure
Absent femoral pulses
Severe metabolic acidosis
Management of coarctation of the aorta
Surgical repair
What is interruption of aortic arch
Aorta does not continue to lower body - instead the connection to the pulmonary artery becomes the vessel and continues this way, there is also a VSD therefore cardiac output is maintained via left-to right flow across duct
What is Hypoplastic left heart syndrome?
Underdevelopment of the left side of the heart - surgical treatment with complicated operation
What is the most common childhood arrhythmia
Supra ventricular tachycardia
Treatment of supraventricular tachycardia in neonate
Very fast heartbeat (250-300bpm) therefore need circulatory and respiratory support
Vagal stimulating manoeuvres (carotid sinus massage or cold ice pack to face) successful in 80%
IV adenosine or cardio version if that fails
Maintenance with flecainide or sotalol
Resting ECG will remain normal but 90% will have no further attacks after infancy therefore treatment can be stopped at age 1
What mostly causes syncope in teenagers
Neurocardiogenic, situational, orthostatic or ischaemic causes
Features of a cardiac cause of syncope
Symptoms on exercise
Family Hx of sudden unexplained death
Palpitations
What age usually affected by rheumatic fever
5-15 years
Following group a b-haemolytic strep -2-6 weeks later
Most common cardiac sequela of rheumatic fever
Mitral stenosis, can also get carditis, also less frequently aortic, tricuspid and rarely pulmonary disease
Acute management of rheumatic fever heart disease
Aspirin for inflammation and bed rest
If aspirin doesn’t work then corticosteroids
Antibiotics if evidence of persisting infection
Management following resolution of acute rheumatic fever episode
Prophylaxis with monthly penicillin injections
Up until the age of 18-21
Severity of episodes influences length of treatment
What are all children with congenital heart disease (except for Secundum ASD) at high risk of
Infective endocarditis - highest risk with turbulent jet of blood - eg. VSD, coarctation of the aorta and persistent DA
Most common organism for infective endocarditis
A-haemolytic strep
Treat with high dose penicillin + amino glycoside given IV for 6 weeks
