Cardio - 2

Question 1

Which are the duct-dependent lesions?

Answer 1

Coarctation of the aorta
Tetralogy of Fallot
Pulmonary stenosis, atresia
Tricuspid atresia

CYANOTIC:
Hypoplasic left heart syndrome
Transposition of great arteries

Death if duct closes!

Question 2

What is the immediate management of a closing duct in a duct-dependent lesion?

Answer 2

Withhold high concentration of inspired oxygen
Administer iv Prostaglandin E2 (opens duct)

Maintain ABC

Question 3

What are the presenting features of coarctation of the aorta?

Answer 3

Depends on anatomical site. Usually where the ductus arteriosus inserts - when it constricts to close, aorta may become constricted. Thus, it usually presents on day 2 with acute circulatory collapse.

Sick baby. Heart failure (pale, sweaty, irritable, SOB).
Absent femorals.
Lower extremity cyanosis (when duct still patent)
Severe metabolic acidosis

Weak/unequal pulses or BP

Duct-dependent lesion in neonatal period-
HTN in older child.
Ejection-systolic murmur between shoulder blades

Question 4

What are the CXR and ECG findings in coarctation of the aorta?

Answer 4

CXR - cardiomegaly from HF and shock

ECG - normal

Diagnosis made with echo usually, which can also show other anatomical defects (such as concurrent bicuspid AV)

Question 5

Which syndrome is coarctation of the aorta highly associated with?

Answer 5

Turner syndrome (45XO)

Question 6

What is the management of coarctation of the aorta?

Answer 6

Balloon angioplasty (via cardiac catheter)
Sometimes stent

Surgery - remove the narrow part of the aorta and reconstruct or patch.

Often, HTN remains and medication + cardiologist follow up needed

Question 7

Which CHDs is coarctation of the aorta associated with?

Answer 7

Bicuspid aortic valve

Question 8

What is venous hum?

Answer 8

Normal phenomenon in up to 20% of children.
Best heard just above right clavicle, radiates into neck. Continuous and constant.

Can typically be obliterated by brief digital pressure on the ipsilateral internal jugular vein.

Question 9

What are the possible causes for heart failure which need to be eliminated and treated?

Answer 9

Sepsis + other systemic disease
Electrolyte imbalance (eg. hypocalcaemia)

Question 10

What are the general measures taken in paediatric heart failure?

Answer 10

Nutritional support in infants (150kcal/kg/d)
Children/adolescents 25-30kcal/kg/day

High protein (aa essential), low fat, low carbs

If acyanotic, O2 when sats < 90%
If cyanotic, O2 is not indicated (has no effect)

Reduction of salt intake if fluid retention. Reduction of fluid intake if edema or unresponsive to diuretic therapy or hyponatraemia

Question 11

What is the medical management of paediatric heart failure?

Answer 11

Diuretics - reduce systemic, pulmonary and venous congestion. Spironolactone very good. Furosemide.
Needs monitoring of electrolytes!

ACE inhibitors - prevent pathophysiological cardiac remodelling/reverse. Also decrease afterload.
Start low-dose and titrate up while monitoring BP, renal function, and serum Potassium

Beta-blockers - low dose in stable patients (titrate up)

Digoxin (ionotrope) in ventricular dysfunction. Reserved for severe reduction in cardiac output.

Question 12

Signs of cardiac failure

Answer 12

Faltering growth
Tachypnoea
Tachycardia
Heart murmur, gallop rhythm
Cardiomegaly
Hepatomegaly
Cool peripheries

Question 13

Symptoms of cardiac failure

Answer 13

Breathlessness, particularly on feeding or exertion

Sweating
Poor feeding
Recurrent chest infections

Question 14

Examination of a child with cardiac symptoms

Answer 14

Cyanosis
Clubbing

Pulse (rate, rhythm character)
BP
Cap refill

Inspection (distress, pre-cordial bulge, scars, ventricular pulse)

Palpation (thrill, apex beat, RV heave)

Auscultation (apex, LLSE, ULSE, URSE) and back (murmurs, loud heart sounds, splitting of heart sounds)

Hepatomegaly
Lung bases
FEMORAL pulses

Question 15

Causes of HF in neonates

Answer 15

Duct-dependent circulation:

Hypoplastic left heart syndrome
Severe coarctation of the aorta
Critical aortic valve stenosis

Question 16

Causes of HF in infants

Answer 16

High pulmonary blood flow:

VSD
AVSD
Large PDA

Question 17

Causes of HF in older children

Answer 17

R or L HF
Eisenmenger syndrome
Rheumatic heart disease
Cardiomyopathy

Question 18

What is usually the cause of HF in the 1st week of life

Answer 18

Left heart obstruction (coarctation of the aorta)

Question 19

What is usually the cause of HF after the 1st week of life

Answer 19

L-to-R shunt

Decreasing pulmonary vascular resistance keeps increasing L-to-R shunt and thus pulmonary blood flow (pulmonary oedema and breathlessness)

Question 20

Initial management of child with cardiac failure

Answer 20

Treat underlying cause

Bed-rest in semi-upright position
Supplemental O2 (unless L-to-R shunt)
Diet
Diuretics and ACIE in L-to-R shunt
Beta blockers and digoxin may help

Prostaglandin infusion if duct-dependent lesion

Question 21

Features of pathologic murmurs

Answer 21

All diastolic and pansystolic
Late systolic
Loud murmurs (3/6)
Continuous murmurs

if abnormal s&s:
SOB, tiredness, failure to thrive, caynosis, clubbing, hepatomegaly

Question 22

Characteristics of innocent heart murmurs

Answer 22

Systolic
Short duration
Low intensity
Intensifies with exercise/fever
May change with posture/head position
No thrill/heave
No radiation
Asymptomatic patient

Left sternal edge

Question 23

What are the types of innocent murmurs

Answer 23

Venous hum
Flow murmur (short, systolic, often in fever)
Musical murmur (systolic, LLSE)

Question 24

Features of venous hum

Answer 24

Common and harmless
Above right clavicle and over right jugular (flow of blood causes vein wall to vibrate)

Hum is heard throughout the cardiac cycle
If finger on jugular, sound stops

Sound may disappear in supine position