Ch 17 - Cardiac disorders Flashcards
Heart disease in children is mostly congenital. The most common congenital abnormalities (account for 80%) can be categorized into 5 groups - name these
Left-to-right shunts (breathless)
Right-to-left shunts (blue)
Common mixing (breathless & blue)
Outflow obstruction in well child (asymptomatic with murmur)
Outflow obstruction in sick neonate (collapsed with shock)
Give 3 examples of left-to-right shunts (breathless)
- VSD
- presistent arterial duct (PDA)
- ASD
Give 2 examples of right-to-left shunts (blue)
tetralogy of fallot
transposition of great arteries
Give 1 example of common mixing defect (blue and breathless)
Atrioventricular septal defect (complete)
Give 2 examples of outflow obstruction in a well child
Pulmonary stenosis
aortic stenosis
Give an example of outflow obstruction in a sick neonate
coarctation of aorta
The most common presentation of congenital heart disease is a heart murmur; give 4 hallmarks of an innoSent ejection mumur
aSymptomatic
Soft blowing murmur
Systolic murmur only (not diastolic)
Left Sternal edge
Causes of HF in neonates (4)
Hypoplastic left heart syndrome (severely underdeveloped LH - small LV & aorta)
Severe AS
severe aortic coarctation (narrowing at area of ductus arteriosus)
interruption of aortic arch (gap between ascending & descending thoracic aorta - in a sense the complete form of coarctation of aorta)
Causes of HF in infants (3)
VSD
ASD
large PDA
causes of HF in older children (3)
Eisenmenger syndrome (RH failure only)
rheumatic HD
cardiomyopathy
Features of HF (6)
Tachycardia,
tachypnoea
murmur
creps oedema
cool peripheries sacral oedema cardiomegaly hepatomegaly
HF in 1st week of life usually results from LH obstruction e.g. coarctation of aorta. What is the pathophysiology? how would you manage?
If very severe coarctation, the only thing that can maintain perfusion is if the ductus arteriosus is open - allowing a R to L shunt “duct dependent circ”.
When this duct closes, the baby rapidly devlopes severe acidosis, collapse & death - unless you restore the ductal patency via PROSTAGLANDIN infusion.
Followed by prompt surgical repair
After 1st week of life progressive HF is probably due to L to R shunt. Explain the pathophysiology (3)
L to R shunt (e.g. VSD) results in eventual increase in pulmonary blood flow > pulmonary oedema > dyspnoea
If an L to R shunt is left untreated will develop Eisenmenger syndrome - explain pathophysiology (4)
Eventually in response to the L to R shunt, the pulmonary vasc resistance will rise (at about 3 months age) > symptoms will improve but if left untreated will develop Eisenmenger syndrome - which is irreversibly raised pulmonary vascular reistance (resulting from chronically raised pulmonary arterial pressure/flow) this also causes the shunt to become from R to L - and the teenager becomes blue. (requires heart lung trasnplant)
Causes of cyanosis (6) (physical sign that causes bluish discoloration of the skin and is due to lack of oxygenated blood)
Cardiac - R to L shunts, common mixing, outflow obstruction
Resp - RDS, meconium aspiration Persistent pulmonary HTN of newborn (pulmonary resistance fails to fall post natally) Septicaemia Inherited metabolic disorders
Name the types of ASDs (2), and where the defects are in these specifically (2)
Secundum ASD (80%) - defect in CENTRE of ATRIAL SEPTUM involving foramen ovale
Partial atrioventricular septal defect (pAVSD) - defect of AV septum (both present with similar signs and symptoms)
Partial AVSD is a defect of AV septum and is characterised by: (2)
An inter-atrial communication between bottom of atrial septum & AV valves Abnormal AV valves (left AV valve has 3 leaflets & leaks - regurgitates)
Features of ASDs (6)
symptoms - usually none,
can get reccurent chest infections,
arrythmias - after 4th decade
Physical signs: Ejection systolic murmur best heard at upper left sternal edge - due to increased flow via pulmonary valve (because of L to R shunt) Fixed & split 2nd heart sound
if partial AVSD will hear an apical pansystolic murmur (due to regurg)
CxR signs of ASDs (3)
Cardiomegaly
Larger PAs
increased vascular markings
ECG signs of ASDs (3)
Secundum ASD shows partial RBBB + RAD (due to RV hypertrophy)
pAVSD shows superior QRS axis
Management of ASDs (2)
treatment only if significant ASD (ie large enough to cause RV dilation)
Secundum ASDs - cardiac catheterization with insertion of an occlusion device pAVSD - require surgery
Murmur of Small VSDs (1)
asymptomatic loud pansystolic murmur at lower left sternal edge
quiet pulmonary 2nd sound (p2) (NO PULMONARY htn)
Ix (3) and management (1) of VSDs
Ix - CxR & ECG (normal), echo + doppler
Management - spontaneous closure - murmur disappears
prevent bacterial endocarditis via good dental hygiene
Large VSDs - same size/larger than aortic valve, features (6)
HF + SOB + failure to thrive after 1 week old recurrent chest infections tachycardia tachypnoea
soft pansystolic mumur/ no mumur (implying larger defect)
apical mid-diastolic murmur - from increased blood flow across the mitral valve after the blood has circulated through the lungs
Ixs (3) & management (3) of VSD
CxR - cardio megaly + large PAs + increased vascular markings + pulmonary oedema ECG - biventricular hypertrophy Echo - pulmonary HTN management - diuretics + ACEis, surgery
PDA - definition, associations (3), features (3)
Failure of DA closure by 1 month
associations - Down’s, prematurity, female, rubella
features - loud P2, continous mumur at upper left sternal edge, bounding pulse (increased pulse pressure)
PDA - Ix (3), management (3)
Ix - CXR, ecg - usually normal, echo management - prostaglandin synthetase inhibitors e.g. ibuprofen; occlusion device closure via catheter, surgery
Hyperoxia (nitrogen washout test): defintion (1), method (3), management (1)
Used to determine heart disease in a CYANOSED infant
give 100% oxygen for 10 min > check right radial PO2, if remains less than 15kPa = congenital cyanotic heart disease (if >20 then not)
managemnet - prostaglandin infusion to maintain ductal patency
Tetralogy of fallot - the 4 cardinal features
PROV: subPulmonary stenosis (causing RV outflow obstruction) RV hypertrophy (as a result of above) Overriding aorta - with respect to septum large VSD
Tetralogy of fallot features (4)
Clubbing
hypercyanotic spells - rapid increase in cyanosis, inconsolable crying + SOB + pallor squatting on exercise in infants loud harsh ESM at left sternal edge
Tetralogy of fallot Ix (3)
CxR - small heart, ‘boot shaped’ because RVH will cause uptilting of apex. pulmonary artery ‘bay’ echo ecg - RVH signs
Tetralogy of fallot management (3)
surgical VSD closure + RV obstruction relief Blalock-taussig shunt - connects a branch of subclavian artery with PA - allowing more blood to flow to lungs symptomtatic treatment of hypercyanotic episodes - propanol, ventilation, morphine
Transposition of great arteries: definition
RV connected to aorta & LV connected to PA = deoxygenated blood to body & oxygenated blood to lungs = INCOMPATIBLE with life; unless mixing occurs - which often does (as ppl with this often have other congenitatl defects) e.g. ASD/VSD/PDA
Transposition of great arteries: features (2)
Consistenly present cyanosis starting from day 2 Loud S2 may have systolic murmur
Transposition of great arteries: Ix (3)
CxR - narrow upper mediastinum (due to anterposterior relationship of great vessels) ‘egg on side’ appearance ECG - norm Echo
Transposition of great arteries: management (3)
Prostoglandin infusion
balloon atrial septostomy
arterial switch procedure
Complete atrioventricular septal defect (common mixing): features (3), Ix (2), management (2)
F - Down’s, cyanosis at birth, SOB
Ix - ECG - superior axis,
Echo - 5 LEAFLET VALVE (in centre of heart)
M - treat HF (diuretics etc.), surgical repair at 3 months
Complex congenital heart disease e.g. tricuspid atresia: definition, features (2), management (3)
D - basically only LV is effective (small and non functional RV)
F - cyanosis in neonate if duct dependent, SOB
M - Blalock Taussig shunt (increase blood flow to lungs) palliation - ‘hemi-fontan operation’ = connect SVC to RPA ‘fontan operation’ = connect IVC to RPA
Outflow obstruction in well child: AS: features (5)
ES murmur Slow rising pulse carotid bruits low volume pulse exertional chest pain syncope
Outflow obstruction in well child: AS: Ix (2), management (2)
CxR - normal/ LVH + post-stenotic ascending aorta dilatation ECG - LVH signs Management - Balloon valvotomy, AV replacement
Outflow obstruction in well child: PS: features (3)
most asymptomatic if critical stenosis neonates have duct dependent circ & will therefore present in 1st few days of life with cyanosis ESM, prominent RV heave (if severe), ejection click
Outflow obstruction in well child: PS: Ix (2) & management (2)
CxR - post-stenotic PA dilation ECG - RVH signs (upright T wave in V1) M - trans-catheter balloon dilation
Outflow obstruction in well child: Adult type aortic coarctation: definition + features (3)
uncommon lesion that is not duct dependent - so presents later as it becomes more severe over yrs
F - asymp, systemic HTN in R arm, ES murmur, collaterals heard wit continuous murmu at the back, radio-femoral delay
Outflow obstruction in well child: Adult type aortic coarctation: Ix (CxR 2 signs, ECG)
CxR - ‘rib-notching’ due to large intercostal collateral arteries for bypassing obstruction.‘3 sign’ - visible notch in descending aorta at site of coarctation ECG - LVH signs
Outflow obstruction in well child: Adult type aortic coarctation: management (2)
Stent insertion surgical repair
Outflow obstruction in sick neonate: aortic coarctation: features (3), Ix (2), Management (3)
F - acute circ collapse at day 2 (as DA closes), absent femoral pulses, severe acidosis
Ix - CxR - cardiomegaly & normal ECG
M - prostaglandin infusion, stent insertion, surgical repair
Outflow obstruction in sick neonate: interruption of the aortic arch: defintion, features (4), management (3)
D - no connection between proximal aorta & distal to DA - so CO is dependent on R-L shunt
F - VSD is usally present; present with shock, associated with Di George syndrome, absent femoral pulses + left brachial pulse
M - Prostaglandin infusion, VSD closure + Aortic arch repair
Outflow obstruction in sick neonate: hypoplastic LH syndrome: definition, features (3), management (2)
D - basically underdevelopment of LH - LV small non functional, mitral & aortic valve atresia, aortic coarctation
F - all peripheral pulses absent, collapse, acidosis
M - norwood procedure, hemi-fontan at 6 months, fontan at 3 years
SVTs: features (3), ix (1)
F - most common childhood arrythmia, HR rapid - 250-300bpm; hydrops fetalis; intrauterine death I
x - ECG - narrow complex tachy 250-300, if WPW syndrome short PR interval + delta wave
SVT management: acute (2), maintenance (2)
Acute - Vagal manoeuvres - carotid sinus massage IV adenosine - breaks re-entry circuit - terminating SVT DC cardioversion
maintenance - Flecainide; ablation of accessory pathway
Congenital complete heart block: defintion, features (3), management (1)
D - prevention of development of normal conductive tissue in heart by anti-ro/la abs in maternal serum (these mumus have connective tissue disorders e.g. sjogrens)
F - most asymptomatic for years, syncope, in utero death, HF
M - Endocardial pacemaker implantation
long QT syndrome: feature (1), complication (1), associations (3)
Feature - sudden LOC during exercise/stress/emotion complication - sudden death from VT if goes unrecognised associations - autsomal dominant inheritance, erythromycin therapy, electrolyte disorders, head injury
Syncope: causes (4),
Common in teenagers, mostly not cardiac cause neurocardiogenic - prolonged standing, vagal symptoms situational - defacation, coughing, urination, swallowing orthostatic - BP fall > 20 mmHg Ischaemic Arrythmic - Heart block, SVT, VT (increase suspicion of cardiac cause if FH of sudden death, exercise symptoms, palpitations)
Rheumatic fever: causes, features (5), Ix (1), management (3)
C - S. Pyogenes (5-15yr olds) F - Joints - migrating polyarthralgia, myocarditis, subcutaneous nodules, erythema marginatum, syndenham’s chorea mitral stenosis most common long term damage Ix - ECG - prolonged PR interval M - NSAIDs, steroids, ABs
IE: causes (2), features (4), Ix (3), mangement (2), prophylaxis (1)
C - S. viridans, enterococcus, S. aureaus F - roth spots, janeway, oslers, splinter haemorrhages, clubbing, splenomagly, haematuria, changing murmur Ix - blood culture, Echo, CRP/ESR M - high dose penicillin, aminoglycoside P - good dental hygiene
