Cardiac problems Paeds.txt

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Cardiac problems Paeds.txt
2011-07-07 19:12:19


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  1. What is the most common group of structural malformation in children?
    Congenital heart disease
  2. What kind of shunt is an acyanotic heart lesion? (which direction)
    • L to R shunt
    • ie baby does not have cyanosis
  3. what are the 3 most common acyanotic heart lesions?
    • VSD
    • PDA
    • ASD
  4. What are the 3 types of outflow obstruction congenital heart lesion? (these are ACYANOTIC)
    • Pulmonary stenosis
    • Aortic stenosis
    • Coarctation of the aorta
  5. What are the 3 cyanotic congenital heart lesions?
    • Tetralogy of fallot
    • Transposition of the great arteries
    • Atrioventricular septal defect (complete)
  6. In the fetus, which atrium has higher pressure L or R and why?
    • L has lower pressure as little blood returning from lungs
    • R has higher pressure as it receives all the SYSTEMIC VR inc. blood from PLACENTA
    • What happens to the circulation with the first breaths?
    • Resistance to pulmonary blood flow falls
    • vol of blood through the lungs increases x6
    • so get rise in LA pressure
    • at same time as placenta is excluded from circulation → less blood returning to RA
  7. what causes the flap valve of the foramen ovale to close?
    Change in pressure difference – now L>R
  8. What does the DA connect and when does it close?
    • Connects pulmonary artery to aorta in fetal life
    • Normally closes in first few hours/days
  9. When does a baby with a duct dependent circulation present?
    1-2 days of age when duct closes their condition deteriorates dramatically
  10. What are the 5 ways of congenital heart disease presenting?
    • Antenatal cardiac US diagnosis
    • Heart murmur
    • Cyanosis
    • Heart failure
    • Shock
  11. Which mothers have a detailed fetal echocardiogram done?
    • Downs syndrome
    • Parents have previous child with heart disease
    • Mother has congenital heart disease
  12. What is the most common presentation of a congenital heart disease?
    Heart murmur
  13. What is an innocent murmur?
    • In a normal heart
    • Turbulent flow in outflow tracts/vessels either side of heart
  14. What are the 2 types of innocent murmur?
    • Ejection murmur: turbulent blood flow in outflow tract, not assoc with structural abnormality. Soft blowing systolic
    • Venous hum: turbulent flow in HEAD AND NECK VEINS.
  15. Where do you hear a venous hum? What phase?
    • Low pitch rumble heart beneath CLAVICLE
  16. What increases a venous hum?
    • Inspiration
    • Louder after exercise
  17. What can a venous hum be mistaken for and how do you distinguish the 2?
    • Mistaken for PDA
    • But venous hum disappears on lying flat or with compression of jugular veins on the same side
    • What are the hallmarks of an innocent ejection murmur? (clue…)
    • 5 s’s
    • Soft
    • Systolic murmur: diastolic murmur by itself is NEVER INNOCENT
    • sternal edge – left (localised)
    • no added sounds, no radiation
    • aSymptomatic patient
  18. Why are innocent murmurs often heard during febrile illness/anaemia?
    Due to increased CO
  19. Why do some infants with VSD or PDA present after several weeks of age?
    As their pulmonary vascular resistance is still high for a few weeks then falls later
  20. What are the causes of CYANOSIS in a newborn with respiratory distress (>60/min)
    • Cardiac disorders – cyanotic congenital heart disease
    • Resp disorders: surfactant deficiency, MAS, pulmonary hypoplasia
    • Persistent Pulmonary Hypertension of the Newborn (PPHN): failure of the pulmonary vascular resistance to fall after birth
    • Infection
    • Inborn error of metabolism
    • Polycythaemia
  21. What level of DEOXYGENATED Hb gives rise to central cyanosis?
    Deoxygenated blood exceeds 5g/dL
  22. In the neonatal period, what are the 2 main categories, causes of cardiac cyanosis?
    • 1. Reduced pulmonary blood flow: infants with duct-dependent pulm circ (relies on DA – so when it closes they become severely cyanosed. They have ROTO so depend on PDA. Severe cyanosis develops when duct closes. Also in Fallot’s get pulmonary stenosis so ROTO
    • 2. Abnormal mixing of systemic venous and pulmonary venous blood: present with cyanosis first 2 days. TGA there must be some mixing.
  23. On chest x-ray, how do you differentiate between the 2 main causes of cyanotic heart disease?
    • Abnormal mixing: pulmonary vascularity is increased, pulmonary plethora is apparent
    • Inadequate pulm blood flow: pulmonary vascularity decreased, oligaemic lung fields
  24. If echo is unavailable, how is congenital cyanotic heart disease confirmed?
    • HYPEROXIA TEST (nitrogen washout)
    • Infant is placed in 100% oxygen for 10 minutes
    • If the R radial arterial PaO2 remains low <15KPa then cyanotic congenital heart disease can be diagnosed if lung disease & PPHN
    • If the PaO2 > 20 then it is NOT cyanotic heart disease
  25. How is central cyanosis due to congenital heart disease distinguished from that due to respiratory disease?
    Failure of R radial artery PO2 to rise above 15kPa after breathing 100% for 10 minutes
  26. What sort of heart lesion do most infants with cyanotic heart disease presenting in first few days of life have? And so what is the Rx?
    • Duct dependent (as closes in first few days)
    • Rx = maintenance of the ductal patency with PGE
  27. What are potential SE of PGE?
    • Apnoea
    • Jitterniess
    • Seizures
    • Flushing
    • Vasodilation
    • Hypotension
  28. What are the most common symptoms of heart failure in children?
    • Breathlessness – esp on feeding/exertion
    • Sweating
    • Poor feeding
    • Recurrent chest infections
  29. What are the signs of heart failure in an infant?
    • Poor weight gain, failure to thrive
    • Tachypnoea
    • Tachycardia
    • Murmur, Gallop rhythm
    • Enlarged heart
    • Hepatomegaly
    • Cool peripheries
  30. What is the main title and 4 causes of heart failure in the NEONATAL period?
    • Obstructed (DUCT DEPENDENT) systemic circulation
    • Hypoplastic left heart syndrome
    • Critical aortic valve stenosis
    • Severe coarctation of the aorta
    • Interruption of the aortic arch
    • (if the obstruction is very severe, then arterial perfusion may be predominantly by R to L flow of blood via the DA = duct dependent systemic circulation)
  31. What are the main causes of heart failure in INFANCY? Which kind of shunt?
    • L to R shunt – so volume overload to lungs!
    • VSD
    • AVSD
    • Large PDA
  32. In heart failure in infants, when may symptoms increase and then improve and why?
    • Increase up to age of 3 months as the pulmonary vascular resistance FALLS initially
    • Then improve as pulmonary vascular resistance rises in response to the L to R shunt!
  33. If heart failure is untreated in infancy, what complication/syndrome can develop and why?
    • L to R shunt, if untreated get EISENMENGER’S SYNDROME
    • IRREVERSIBLY raised pulmonary vascular resistance due to chronically raised pulmonary artery pressure and flow
  34. What is the treatment of Eisenmenger’s syndrome?
    Heart-lung transplant
  35. Which Ix do you do in suspected heart failure? And what would they show?
    • CXR: enlarged heart, pulmonary congestion/plethora
    • ECG: may be suggestive of heart defect
    • Echo: shows defect and poor contractility of ventricles
  36. What does differential cyanosis in the limbs indicate?
    R to L shunting across the DA
  37. What are the 2 types of ASD? Which is the more common type?
    • Ostium Secundum ASD: 80% of ASDs (more common)
    • Ostium primum ASD (also known as partial AVSD)
  38. Where is the defect in the secundum ASD? And what causes it?
    • High in the atrial septum
    • Enlarged Foramen ovale, inadequate growth of septum secundum or xs absorption of septum primum
  39. Which syndrome is affected by primum ASD /pAVSD?
    Down’s syndrome
  40. Which murmur is AVSD commonly associated with?
    Mitral regurgitation
  41. What are the symptoms of ASD?
    • Asymptomatic commonly
    • Recurrent chest infection/wheeze
    • Heart failure
    • Arrhythmia: 40s onwards
  42. What is an ASD commonly mistaken for?
    Patent foramen ovale
  43. How do you distinguish between an ASD and a patent foramen ovale?
    • PFO opens only in conditions of raised atrial pressure or volumes
    • Whereas ASDs are LARGE and ALWAYS open
  44. What % of people have a patent foramen ovale?
  45. What are the 3 physical signs of ASD?
    • 1. Fixed and widely SPLIT 2nd heart sound (as RVSV is equal in both insp and exp)
    • 2. ESM best heard at upper left sternal edge – due to inc flow across RV outflow tract due to L-R shunt
    • 3. With a partial AVSD – apical pansystolic murmur from the AV valve regurgitation
  46. Is there a murmur generated by the flow across the ASD, why?
    No because it is LOW VELOCITY
  47. What does CXR of ASD show?
    • Pulmonary plethora
    • Cardiomegaly
  48. What does ECG of ASD show?
    • RV hypertrophy
    • Incomplete RBBB
  49. Which Ix is needed to diagnose ASD?
  50. What is the Rx of ASD? And what is it trying to prevent?
    • Surgical – for secundum insertion of an occlusion device
    • Prevent cardiac failure, arrhythmia in later life
  51. When is surgery for ASD best done? Where?
    • 3-5 years of age
    • 30% in cardiac catheter lab
  52. Is endocarditis prophylaxis needed for ASD repair?
    Not for secundum ASD
  53. How are VSDs classified?
    According to size
  54. What are the symptoms of a small VSD?
  55. What are the 2 main signs of a small VSD?
    • LOUD Pansystolic murmur at lower left sternal edge
    • Thrill at lower left sternal edge
    • (quiet P2)
  56. What do CXR, ECG and echo show in small VSD?
    • CXR, ECG are normal
    • Echo shows anatomy of defect.
  57. What is the management of small VSD?
    • Most close spontaneously
    • Need antibiotic prophylaxis of bacterial endocarditis before dental extraction
  58. What are the symptoms of a large VSD?
    • Heart failure
    • Breathlessness
    • Failure to thrive after 1 week old
  59. What are signs of large VSD?
    • SOFT pansystolic murmur (because big hole!)
    • Apical mid diastolic murmur – due to increased flow across mitral valve after blood has circulated through lungs
    • Loud P2 due to raised pulm art DBP
    • Tachypnoea
    • Tachycardia
    • Enlarged liver – due to heart failure
  60. What does CXR of large VSD show?
    • Cardiomegaly
    • Enlarged pulm artery
    • Increased pulm vasc markings
    • Pulm oedema
  61. What does ECG of large VSD show?
    • LVH and RVH
    • Signs of pulm HTN
  62. What is the management of a large VSD – remember medical and surgical
    • Drugs for heart failure: diuretics + captopril (ACEi)
    • Additional calorie input
    • Surgery: at 3-6 months of age to manage heart failure, prevent permanent lung damage from high pressures
  63. What is a complication of a VSD – think about having such a big L to R shunt?
    • Increased flow in pulm vessels → pulmonary hypertension → increased pressure on R heart → reversal of shunt → so then right to left → CYANOSIS!!!
    • = Eisenmenger’s syndrome
  64. What is the main complication of Eisenmengers syndrome, and when does E occur?
    • Cyanosis
    • E occurs in 2nd decade of life
  65. What does the DA connect?
    Aorta to L pulm artery
  66. When does the DA usually close by?
    Fourth day of life
  67. When is a PDA diagnosed?
    If duct does not close after 1 month POST TERM
  68. Which direction is the flow of blood in a PDA?
    • From aorta to pulmonary artery (L→ R)
    • Following the fall in pulm vasc res after birth
  69. Give 3 risk factors for PDA?
    • Preterm infants
    • Downs
    • High altitude
  70. Is the PDA in preterm infants the same as congenital PDA?
  71. What are the 2 main clinical features of a PDA?
    • 1. Bounding pulse due to wide pulse pressure
    • 2. Machinery murmur
    • (if large duct then may get pulm HTN)
  72. Describe the change in murmur type in PDA
    • Initially SYSTOLIC
    • Then as pulmonary vasc res falls – a continuous run off from the aorta to the pulm artery occurs with a continuous MACHINERY MURMUR
    • Hear it beneath the clavicle
  73. Why does the murmur in PDA continue into diastole?
    Because the pressure in the pulm artery is lower than that in the aorta throughout the cardiac cycle
  74. Normally the ECG and CXR features of PDA are normal but if large what are the features similar to?
    Large VSD
  75. What is the management of a PDA?
    • If asymptomatic PDA – must close ALL to prevent bacterial endocarditis (higher risk of pulm vasc dis and BE from PDA than VSD! )
    • Coil or occlusion device via cardiac catheter at 1yr age
    • If large PDA may need surgical close at 1-3 months
  76. Usually PDAs are asymptomatic, but if the duct is large what can happen?
    • L→ R shunt as pulm vasc res falls
    • Heart failure
  77. What are the 3 types of outflow obstruction in the WELL child?
    • Aortic stenosis
    • Pulmonary stenosis
    • Adult type coarctation of the aorta
  78. If you see aortic stenosis, what other things do you have to exclude?
    • Mitral valve stenosis
    • Coarctation of aorta
  79. How does mild aortic stenosis present?
    Asymptomatic murmur
  80. How does severe stenosis present?
    • Reduced exercise tolerance
    • Chest pain on exertion
  81. In the neonatal period how many AS present?
    • Severe heart failure
    • Duct dependent SYSTEMIC circulation leading to shock
  82. What causes aortic stenosis?
    Partial FUSION of the aortic valve leaflets – so restricted LV exit
  83. What is the pulse like in aortic stenosis?
    Small volume, slow rising pulses
  84. What type of murmur do you get in aortic stenosis? And where do you hear it?
    • Ejection systolic murmur radiating to neck
    • Murmur in ‘A’ – upper right sternal edge
  85. What 2 features do you get of the heart sounds in AS?
    • Delayed and soft aortic S2
    • Apical ejection click
  86. What do you see on CXR of AS?
    • Normal or prominent LV
    • Post stenotic dilatation of aorta
  87. What do you see on ECG of AS? (2 main things)
    • LVH – deep S wave in V2 and tall R wave in V6 (>45mm)
    • Downward T wave suggests LV strain and severe AS
  88. What is the management of AS?
    • If symptomatic or high resting pressure gradient across aortic valve need
  89. If there is significant AS what will the children eventually need?
    Valve replacement
  90. What is the pathology of pulmonary stenosis?
    Pulmonary valve leaflets are partly fused together – restrictive RV exit
  91. What type of pulmonary circulation may some neonates with pulmonary stenosis have?
    • Duct dependent pulmonary circulation
    • So they present in first few days of life
  92. What type of murmur do you get in aortic stenosis? And where do you hear it?
    • Ejection systolic murmur
    • Murmur in ‘P’ – upper left sternal edge
  93. Where do you hear an ejection click in pulm stenosis?
    Upper left sternal edge
  94. What happens to HS in pulm stenosis?
    Soft or absent P2
  95. What may you see on CXR of pulm stenosis?
    • Normal
    • Or post stenotic dilatation of pulm artery
  96. What does ECG of pulm stenosis show?
    RVH – upright T wave in V1 indicates RVH in children
  97. Although most children with PS are asymptomatic, what will eventually occur to them?
    • Progressive RVH
    • Reduced exercise tolerance
  98. What is management of pulm stenosis?
    Transcatheter balloon dilatation
  99. Why must you palpate for femoral pulses in cardiovascular examination of any child?
    Detect coarctation of aorta
  100. Which of the 3 outflow obstruction heart defects in a WELL child is not duct dependent?
    coarctation of the aorta
  101. how is coarctation of aorta classified?
    • Preductal: symptomatic infants
    • Postductal: asymptomatic chidren
  102. What is the prognosis of coarctation of the aorta?
    Gradually becomes more severe over many years
  103. What are symptoms of coarctation of the aorta?
    • Asymptomatic
    • May have leg pains or headache
  104. What do you find on cardiac examination in coarctation of the aorta? – think systematically
    • Pulse: radiofemoral delay (due to blood bypassing the obstruction via collateral vessels in the chest wall – hence pulse in legs is delayed)
    • BP: always systemic hypertension in the R arm
    • Heart: ESM at upper sternal edge
  105. What 2 things do you see on CXR of coarctation of aorta?
    • Rib NOTCHING due to development of large collateral intercostal arteries under the ribs posteriorly to bypass obstruction
    • 3 sign: aortic knob → notch where coarctation is →post stenotic dilatation
  106. What does ECG of coarcation show?
  107. What is management of coarctation, when does this happen?
    • When the condition becomes severe (assess by echo), then STENT at cardiac catheter
    • May need surgical repair
  108. What is the other name for adult type coarctation of the aorta?
    Post ductal coarctation
  109. What is the other name for interruption of the aortic arch?
    Pre ductal coarctation
  110. What is the problem with pre ductal coarctation?
    No connection between aorta PROXIMAL and DISTAL to the arterial DUCT
  111. What other heart defect is commonly seen with preductal coarctation?
  112. When does preductal coarctation present? With what features?
    • Neonatal – when DA closes get heart failure!
    • Features of duct dependent systemic circulation
  113. On diagnosis of preductal coarctation what needs to be done?
    PG infusion to maintain ductal patency and transfer to cardiac centre for surgery
  114. What is the management of preductal coarctation?
    Complete correction with closure of VSD and repair of aortic arch in first few days of life
  115. What other conditions is preductal coarctation associated with?
    • DiGeorge syndrome
    • Palatal defects
    • Immunodeficiency
    • hypoCa
    • 22q11.2 gene deletion
  116. What are the 2 forms of outflow obstruction in the sick infant?
    • Interruption of aortic arch (preductal coarctation)
    • Hypoplastic left heart syndrome
    • They are both DUCT DEPENDENT
  117. What is hypoplastic left heart syndrome?
    Underdevpt of entire L side of heart
  118. What happens when the DA constricts in hypoplastic L heart syndrome?
    • Profound acidosis and rapid cardiovascular collapse as it is a duct dependent systemic circulation with no L heart!
    • Therefore need to give PG urgently!
  119. On examination how do you tell between coarctation and hypoplastic left heart syndrome?
    • Coarctation: weak FEMORAL pulses
    • Hypoplastic L heart: ALL PERIPHERAL pulses are weak/absent
  120. What is Rx of hypoplastic L heart syndrome?
    Norwood procedure – difficult neonatal operation!
  121. In congenital heart disease, what are the 2 causes of CYANOSIS?
    • 1. Decreased pulmonary blood flow, with R to L shunt – FALLOTS
    • 2. Abnormal mixing of systemic and pulmonary venous return – TRANSPOSITION OF GREAT ARTERIES & TRICUSPID ATRESIA
  122. What is the most common cause of cyanotic congenital heart disease?
    Tetralogy of fallot
  123. What are the 4 main features of Fallot?
    • Large VSD
    • Overriding aorta
    • Subpulmonary stenosis → RVOTO
    • RVH as a result
  124. When are most Fallots diagnosed?
    • Antenatally
    • Or after identifying MURMUR in few months of life
    • Rapid increase in cyanosis
    • Associated with irritability or inconsolable crying due to severe HYPOXIA and BREATHLESSNESS and PALLOR
    • Due to tissue acidosis
  126. What are signs of Fallots?
    • Clubbing of fingers and toes – older children
    • Cyanosis
    • Loud single S2 (only A2)
    • Loud ESM
  127. What type of murmur do you get in Fallots? (remember one of the 4 features…valve one)
    ESM at LSE
  128. What happens to heart sound in Fallots?
    Single 2nd HS – A2
  129. What causes the murmur to become shorter and cyanosis to increase?
    • Increased RVOTO
    • Mainly muscular and BELOW the pulm valve
  130. During a hypercyanotic spell what happens to the murmur in Fallots?
    Very short or inaudible
  131. Why is it important to recognise hypercyanotic spells?
    They may lead to myocardial infarction, CVA, death if untreated
  132. In fallots what happens on exercise?
    Squatting – late in infancy
  133. What is the ECG of Fallots at birth and later?
    • Birth: normal
    • Later: RAD, RVH – upright T wave in V1 with pure R wave (no S wave)
  134. What is the characteristic feature on CXR of Fallots?
    • Boot shaped (uptilted apex) heart caused by RVH
    • As there is pulm stenosis – get decreased pulm blood flow – so dec pulm vasc markings
  135. What is the initial management of Fallots? And when is corrective surgery done? What are the 2 main aspects of surgery
    • Medical
    • Surgery at 6 months age
    • 1. Patch closure of VSD
    • 2. Widening of RVOT
  136. What needs to be done with neonates who are very cyanosed?
    • SHUNT to increase pulm blood flow
    • Artificial tube between subclavian artery and pulm artery – modified Blalock Taussig shunt
    • Or balloon dilatation of RVOT
  137. What is management of hypercyanotic spells?
    • Morphine – relieve pain and abolish hyperpnoea
    • Sodium bicarbonate – correct acidosis
    • Propranolol – peripheral vasoconstriction to relieve subpulmonary muscular obstruction that is the cause of reduced pulm bld flw.
    • Iv fluids
  138. What can be done to prevent hypercyanotic spells?
    Oral propranolol
  139. What is the problem in transposition of the great arteries?
    • Aorta is connected to the RV
    • Pulmonary artery is connected to LV
    • The blue blood us returned to the body
    • Pink blood is returned to the lungs
  140. Describe the 2 circulations in TGA? Is it compatible with life?
    • 2 PARALLEL circulations
    • Unless mixing of blood between the 2 circulations, the condition is incompatible with life
  141. What is the main symptom of TGA?
    • CYANOSIS!!
    • Can be profound and life threatening
  142. When does TGA usually present?
    • Day 1-2 of life
    • When ductal closure leads to a marked reduction in mixing of the desat and sat blood
  143. What other anomalies would make the cyanosis less severe?
    Mixing of blood from VSD
  144. What is the heart sound in TGA?
  145. When may you see clubbing in TGA?
    Rare child who presents after 1 yr of life
  146. What does CXR of TGA look like?
    • Narrow upper mediastinum with an egg on side appearance of heart shadow
    • Increased pulmonary vasc markings
  147. What is the main aspect of management of TGA?
    • To improve mixing of saturated and desat blood
    • So maintain PDA – PGE infusion
  148. What is the life saving procedure for TGA?
    • Balloon atrial septostomy
    • Catheter with balloon at tip through umb/fem vein to RA and foramen ovale - balloon inflated when in LA then pulled through the atrial septum – tear the septum and makes the flap valve of the foramen ovale incompetent – allow mixing of systemic and pulm venous blood within the atrium
  149. What is the definitive Rx of TGA and when is it done?
    • Surgery – arterial switch procedure
    • Done first few days of life
    • Pulm artery and aorta transected above the valves and switched over
  150. As well as the pulm and aorta which other arteries need to be transferred in surgery for TGA?
    Coronary arteries transferred to the new aorta
  151. Who is more likely to get AVSD?
    Downs syndrome
  152. What is a complication of AVSD?
    Pulmonary hypertension
  153. What are the different ways AVSD can present?
    • Antenatal US screening
    • Cyanosis at birth or HF at 2-3weeks
    • Routine echo screening for Downs
  154. What do you always see on ECG of AVSD?
    Superior axis
  155. What is the management of AVSD?
    • Treat heart failure medically: diuretics, captopril, calories
    • Surgical repair at 3-6months
  156. What happens to the chambers in tricuspid atresia?
    • Only LV is effective
    • R is small and non functional
  157. Where is there common MIXING of sys and pulm venous return?
  158. How does tricuspid atresia present?
    • Cyanosis in newborn period if duct dependent
    • May be well at birth then become cyanosed or breathless
  159. What is management of tricuspid atresia?
    • Blalock Taussig shunt – between subclavian and pulm artery
    • Pulm artery banding to reduce pulm blood flow if breathless
  160. Why is complete corrective surgery for tricuspid atresia not possible?
    As there is only one effective functioning ventricle
  161. What operation can be done to bypass the RA and RV?
    • Glenn: Connecting the SVC to the pulm artery after 6 months
    • Fontan: connect IVC to pulm artery
  162. how is rheumatic fever diagnosed?
    • Duckett Jones criteria
    • 2 major
    • or 1 major 2 minor
    • as well as evidence of preceding strep infection eg ASOT
  163. what are major criteria?
  164. what are minor criteria?
    • FLAPPP
    • fever
    • leucocytosis
    • arthralgia
    • positive acute phase protein
    • previous rheumatic fever
    • prolonged PR interval on ECG
  165. what is Rx of rheumatic fever?
    • bed rest
    • high dose aspirin to suppress fever and arthritis
    • steroids for severe carditis
    • diuretics and ACEi for heart failure
    • abx if still infection
  166. how can recurrent attacks of rheumatic fever be prevented?
    • prophylactic penicillin
    • lifelong
  167. what is main complication of rheumatic fever?
    scarring and fibrosis of mitral valve
  168. what are the 2 main cardiac infections?
    • infective endocarditis
    • myocarditis
  169. what is main cause of infective endocarditis?
    strep viridans (alpha haemolytic)
  170. what Ix for IE?
    • 3 separate blood cultures in first 24 hours
    • echo
    • CRP raised
  171. what is treatment of infective endocarditis?
    • high dose ampicillin
    • gentamicin
    • 4-6 weeks iv
  172. which children need abx prophylaxis against IE?
    all CHD except osteum secundum defects
  173. what age children does myocarditis affect?
    neonates and infants
  174. what are the 3 main causes of myocarditis?
    • coxsackie
    • echovirus
    • rubella
  175. what are the 2 different presentations of myocarditis?
    • acute: cardiovascular collapse
    • gradual: congestive cardiac failure
  176. what is Rx of myocarditis?
  177. what is complication of myocarditis?
    chronic dilated cardiomyopathy
  178. what is the upper limit of normal sinus rhythm in children?
  179. what is the significance of premature atrial and ventricular contractions in children?
    common and benign
  180. what is heart rate in SVT?
    > 220/min
  181. what is the cause of SVT in 95% of children?
    accessory connection
  182. how do children and infants present with SVT?
    • children - asymptomatic
    • infants - heart failure: poor feed, sweat, irritable
    • older children - palpitations
  183. how is the diagnosis of SVT made?
    • ECG
    • narrow complex tachycardia
    • P waves after QRS complex
  184. which syndrome is related to SVT in children? what causes it?
    • Wolff-Parkinson White syndrome
    • accessory bundle of Kent - allows premature activation of the ventricles
  185. when can you see features of WPW on ECG? what are they?
    • when in sinus rhythm
    • short PR
    • wide QRS
    • slurred upstroke - delta wave
  186. how is an acute episode of SVT managed in children?
    • need to terminate and restore SR by
    • - vagal stimulation: ice cold compress to face or carotid sinus massage
    • - iv adenosine
    • - synchronised DC cardioversion if above fail
  187. what is prognosis of SVT?
    • good
    • majority have no further episodes after infancy
  188. if a child has persistent paroxysms of SVT what can be done?
    radiofrequency ablation