Paediatric Cardiology 3 Flashcards
What syndromes are associated with coarctation of the aorta?
Turner syndrome
Shone complex
P wave criteria for atrial hypertrophy:
RAH >3mm high
LAH >0.1s long (2.5 squares) or >0.08 in infants, bifid P wave
What is the normal BP difference between arms + legs?
What about in coarctation?
Legs - 10-20mmHg higher due to arterial pressure waves and stretch reflex.
Neonates - same in arms and legs
Coarctation - arms > legs
What % of people with coarctation have bicuspid AV?
70%
ECG signs of LVH:
- LAD for the patient’s age
- QRS voltages in favour of the LV (in the presence of a normal QRS duration): R in I, II, III, aVL, AVF, V5 or V6 > ULN for age; S in V1 or V2 > ULN for age
- Abnormal R/S ratio in favour of the LV; R/S ratio in V1 and V2 < LLN for age
- Q in V5 and V6, 5 mm or more, plus tall symmetric T waves in the same leads (“LV diastolic overload”)
- In the presence of LVH, a wide QRS-T angle with the T axis outside the normal range indicates “strain” pattern; this is shown by inverted T waves in I or AVF.
What does PHACE stand for in PHACE syndrome?
P - posterior brain fossa malformations H - haemangiomas A - arterial anomalies C - cardiac, coarctation of the aorta E - eye and endocrine
What would be complications expected after RVOT obstruction repair?
RBBB if RV opened
Pulmonary regurgitation e.g. with valvotomy
What findings do you expect with pulmonary regurgitation?
- Majority is well tolerated and therefore asymptomatic
- Decrescendo, low pitched diastolic murmur at the ULSE/mid LSE upper and midleft sternal border
- CXR - Enlarged MPA and possibly RV enlargement
- ECG - normal or mild RVH
Describe the murmur of mitral regurgitation:
Mild - high-pitched, apical holosystolic murmur
Moderate to severe - low-pitched, apical mid-diastolic rumble
What syndromes and congenital anomalies are associated with MV prolapse?
- Fragile X
- Marfan
- Ehlers-Danlos
- Straight back syndrome
- Pseudoxanthoma elasticum
- Osteogenesis imperfecta
- Scoliosis
Being female!
May be inherited - autosomal dominant
When are tet spells most commonly seen in Tetralogy of Fallot (and what do you do about them)?
First 2 years of life, after crying and on waking
Reduction in pulmonary blood flow
Knees-to-chest, oxygen, morphine
Name cardiac lesions associated with Tetralogy of Fallot and approximate percentages:
R sided arch - 20% Coronary artery anomalies - 5-10% Absent pulmonary valve Absent branch PA (L>R) PDA ASD AVSD esp if Trisomy 21
Describe the presentation and clinical findings in Tetralogy of Fallot in infancy:
Infancy/young toddler:
- Heart failure - Dyspnoea, diaphoresis, poor feeding, may have cyanotic “tet spells”
- Cyanosis usually in the first year of life unless severe RVOT which may present early in life.
Examination
- normal pulse
- substernal RV impulse
- systolic thrill LSE 3rd and 4th spaces
- harsh ejection systolic murmur LSE (mixed RVOT/VSD), radiates to lungs, can get quieter with tet spell
- Single S2
What are the ECG findings in Tetralogy of Fallot?
- Right axis deviation
- RVH - may have dominant R wave in chest leads, positive T wave in V1
- Tall peaked P wave for RA enlargement
Complications of late repair/diagnosis of Tetralogy of Fallot:
- Cerebral thromboses due to extreme polycythemia and dehydration (<2 years)
- Brain abscess
- Endocarditis
Normal value for PA pressure?
15mmHg
Normal value for atrial pressures?
<10mmHg
Formula for Qp/Qs:
(Aortic sats - mixed venous sats) / (pulmonary vein sats -pulmonary artery sats)
When do you fix VSD?
- Heart failure
- Qp>Qs is 2 or higher
Formula for pulmonary vascular resistance:
What are normal values?
PVR in units x m^2 = (mean PA pressure - left atrial pressure) / (pulmonary blood flow in L/min/m^2)
Normal: 1-2
Mild: 2-4
Moderate: 4-6
Severe: >8
Previously correlated with biopsies done for PVOD
Which cardiac conditions are associated with neurofibromatosis?
- Pulmonary Stenosis
ECG findings in antidromic SVT?
- Rate usually 200 – 300 bpm.
- Wide QRS
- anterograde conduction via accessory pathway, retrograde conduction via AV node.
- ~5% of patients with WPW
DO NOT GIVE DIGOXIN
ECG findings in orthodromic SVT?
- Rate 200-300bpm
- P in QRS or retrograde
- Narrow QRS unless BBB/aberrant conduction
- anterograde conduction via AV node, retrograde conduction via accessory pathway
- QRS Alternans – phasic variation in QRS amplitude associated with AVNRT and AVRT, normal QRS amplitude
- TWI, ST depression
How does iloprost work?
- Synthetic analogue of prostacyclin PGI2.
What is the abnormality in the cardiac action potential which results in QT prolongation in LQT1, LQT2 and LQT5?
- Prolonged potassium efflux
- QT 1-3 is 97% of all cases
- All but QT3 are potassium channel issues
Which cardiac condition is most commonly associated with neurofibromatosis?
PS
Describe the presentation of untreated ToF in childhood:
Tet squat/dyspnoea with exertion, dusky blue skin, gray sclerae with engorged blood vessels, and marked clubbing of fingers and toes.
Examination
- normal pulse
- substernal RV impulse
- systolic thrill LSE 3rd and 4th spaces
- harsh ejection systolic murmur LSE (mixed RVOT/VSD), radiates to lungs, can get quieter with tet spell
- Single S2
What are the causes of complete heart block in children?
- Most common is surgery for congenital heart disease - usually well, post-op
- drugs - digitalis/digoxin
- infective - viral myocarditis, Lyme, EBV
- post-infective - ARF
- neonatal lupus
- sarcoidosis
What type of immune reaction is acute rheumatic fever?
Type II
How does simvastatin work?
Upregulation of low density lipoprotein (LDL) receptor activity
‘Egg on a string’ heart on CXR suggests:
TGA
‘Snowman sign’ on CXR suggests:
Supracardiac/Type 1 TAPVR
What are the first 3 normal aortic branches?
R brachiocephalic, L common carotid, L subclavian
Which type of AVRT gives you WIDE complex tachycardia?
Antidromic atrio-ventricular re-entrant tachycardia
Which neonatal congenital heart lesion presents with LVH?
Tricuspid atresia (although other signs must be in keeping!!)
Which congenital heart lesions present with LAD?
- Tricuspid atresia
- Endocardial cushion defects (both complete atrioventricular [AV] canal and primum ASD) b
What congenital anomalies are associated with WPW?
- TGA and Ebstein’s
Describe examination and investigation findings of a large VSD:
Exam - Prominent left precordium is common, palpable parasternal lift, displaced apex+apical thrust, thrill. May be quieter murmur. Louder P2 due to pulmonary hypertension. Mitral rumble - mid-diastolic, low-pitched rumble at the apex with increased blood flow across the MV
Ix - ECG shows biVH, notched/peaked P wave. CXR frank cardiomegaly + failure with oedema or effusion. Qp : Qs ratio of ≥2 : 1.
Describe typical clinical presentation of large VSD:
Dyspnoea, feeding difficulties, poor growth, profuse diaphoresis, recurrent pulmonary infections, and cardiac failure in early infancy (2-6 weeks). May get cyanosis with crying/infections or shunt reversal.
What is the most common cardiac anomaly in Costello syndrome?
Valvular PS
What is the most common cardiac anomaly in Alagille?
ToF
What are the triggers for the different types of long QT?
- 1: 5-15yo male, swimming/emotion
- 2: Female, post partum, loud noise/surprise e.g. alarms
- 3: Young men who die in their sleep, emotion
How do you calculate CO when you are given sats and VO2?
Ca-Cv in ml/L so you should get O2 in mL/L
Multiply same by sats to get difference
CO = VO2/(Ca-Cv)
What’s actually absent in PCD/Kartagener?
Absent dynein arms
Associated with dextrocardia
Look for Nasal Nitric Oxide - LOW in PCD
