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