Congenital Heart Disease

Question 1

Types of congenital heart disease

• Acyanotic
• Cyanotic
• Common mixing
• Outflow obstruction

Answer 1

• Acyanotic (L→R shunt) → Breathless
  
  • Ventricular septal defect (VSD) ~25%
  • Patent ductus arteriosus (PDA)
  • Atrial septal defect (ASD)
• Cyanotic (R→L shunt) → Blue
  
  • Tetralogy of Fallot
  • Transposition of the great arteries
• Common mixing → Breathless + Blue
  
  • Atrioventricular septal defect (AVSD)
  • Tricuspid atresia
• Outflow obstruction
  
  • Pulmonary stenosis
  • Aortic stenosis
  • Coarctation of the aorta

Question 2

Aetiology / Risk factors of congenital heart disease

Answer 2

• FHx
• Maternal factors
  
  • Rubella (PDA)
  • Diabetes mellitus
  • Phenylketonuria
  • Drugs & toxins
    
    • Warfarin (PDA)
    • Foetal alcohol syndrome
      
      • ASD
      • VSD
      • Tetralogy of Fallot
• Chromosomal abnormalities
  
  • Down syndrome (trisomy 21)
    
    • AVSD
  • Turner syndrome (45XO)
    
    • Coarctation
    • Aortic stenosis
  • DiGeorge syndrome (22q11 deletion)
    
    • Tetralogy of Fallot
    • VSD

Question 3

Presentation of congenital heart disease

Answer 3

• Antenatal cardiac ultrasound diagnosis
  
  • Foetal anomaly scan 18-20 weeks
• Detection of a heart murmur
• Heart failure
• Shock
• Cyanosis

Question 4

Characteristic features of an innocent/flow murmur

Answer 4

• Majority of heart murmurs are ‘innoSent’:
  
  • aSymptomatic
  • Systolic
  • Soft
  • left Sternal edge
  • ↑ when Supine
    
    • May present with ↑ CO
      
      • Febrile (important to re-examine when well)
      • Anaemia

Question 5

Presentation of heart failure (congenital)

Answer 5

• Symptoms
  
  • Breathless (particularly on feeding/exertion)
  • Sweating
  • Poor feeding
  • Recurrent chest infections
• Signs
  
  • FTT
  • Tachypnoea
  • Tachycardia
  • Heart murmur
  • Cardiomegaly
  • Hepatomegaly
  • Cool extremities
  • Weak pulses

Question 6

Presentation of shock (paediatric)

Answer 6

• Signs
  
  • ↑ capillary refill time (cool extremities)
  • Tachycardia
  • Mottling of the skin
  • ↓ urine output
  • Weak/absent pulses

Question 7

Ventricular septal defect (VSD)

• Clinical features
• Investigations
• Management
• Complications

Answer 7

• Acyanotic (L→R shunt)
• Symptoms
  
  • Asymptomatic (small lesion)
  • Heart failure with SOB
  • Recurrent RTI (pulmonary hypertension → oedema)
• Signs
  
  • Pansystolic murmur (LLSE)
  • Heart failure (large lesion)
    
    • Tachycardia
    • Tachypnoea
    • Hepatomegaly
• Investigations
  
  • CXR
    
    • Cardiomegaly
    • Enlarged pulmonary arteries
    • ↑ pulmonary vascular markings
    • Pulmonary oedema
  • ECG
    
    • Biventricular hypertrophy
  • Echo
• Management
  
  • Spontaneous closure
  • Heart failure
    
    • Diuretics + Captopril
  • Surgical closure
• Complications
  
  • Eisenmenger syndrome
    
    • Untreated pulmonary hypertension → permanent shunt reversal (R→L) + cyanosis
    • Rx: heart-lung transplant

Question 8

Atrial septal defect (ASD)

• Clinical features
• Investigations
• Management

Answer 8

• Acyanotic (L→R shunt)
• Symptoms
  
  • Usually none
• Signs
  
  • Systolic murmur (ULSE)
  • Fixed, widely split S2
• Investigations
  
  • CXR
    
    • Cardiomegaly
    • Enlarged pulmonary arteries
    • ↑ pulmonary vascular markings
  • ECG
    
    • RVH
    • Incomplete RBBB
  • Echo
• Management
  
  • Catheter occlusion device
  • Surgical correction

Question 9

Patent ductus arteriosus (PDA)

• Clinical features
• Investigations
• Management
• Complications

Answer 9

• Acyanotic (L→R shunt)
• Signs
  
  • Continuous machinery murmur (beneath L clavicle)
  • Collapsing / bounding pulse
  • Heart failure
  • Pulmonary hypertension (SOB, recurrent RTI)
• Investigations
  
  • CXR
    
    • Big aorta
    • Cardiomegaly
    • Enlarged pulmonary arteries
    • ↑ pulmonary vascular markings
  • ECG
    
    • Normal
    • LVH
    • RVH
  • Echo
• Management
  
  • Drugs
    
    • Dexamethasone (preterm labour)
    • Ibuprofen
    • Indometacin
  • Surgical correction
• Complications
  
  • Bacterial endocarditis

Question 10

Tetralogy of Fallot

• Definition
• Clinical features
• Investigations
• Management

Answer 10

• Cyanotic (R→L shunt)
• Definition
  
  • VSD
  • Overriding aorta
  • Pulmonary stenosis
  • RVH
• Signs
  
  • Hypercyanotic episodes
  • Harsh systolic murmur (LLSE)
  • Dyspnoea
  • Squatting on exercise (↑ peripheral vascular resistance → ↓ R→L shunt)
  • Clubbing
• Investigations
  
  • CXR
    
    • ‘Boot-shaped’ heart
    • RVH
    • ↓ pulmonary vascular markings (↓ pulmonary perfusion)
  • ECG
    
    • RVH
  • Echo
• Management
  
  • Hypercyanotic episode
    
    • Place in knee-chest position ( ↑ venous return)
    • Oxygen
      
      • CONTRAINDICATED in cyanotic neonates - ↑ duct closure)
        
        • Morphine (↓ ventilatory drive)
        • Propranolol (IV)
          
          • Relaxes sub-pulmonary muscular obstruction
        • Phenylephrine (α-agonist)
          
          • ↑ systemic vascular resistance above pulmonary resistance
        • Bicarbonate (correct acidosis)
  • Palliative surgery
    
    • modified Blalock-Taussig shunt: subclavian → pulmonary artery
    • Balloon dilatation of R outflow obstruction
  • Surgical correction

Question 11

Transposition of the great arteries

• Clinical features
• Investigations
• Management

Answer 11

• Cyanotic (R→L shunt)
  
  • Incompatible with life unless mixing occurs
• Signs
  
  • Cyanosis
  • Loud S2
• Investigations
  
  • CXR
    
    • ‘Egg on side’ heart
    • ↑ pulmonary vascular markings
  • ECG
    
    • RVH
  • Echo
• Management
  
  • Prostaglandin E2 (maintain duct)
    
    • DO NOT GIVE OXYGEN
      
      • Condraindicated in cyanotic neonates - ↑ duct closure
  • Balloon atrial septostomy
  • Surgical correction

Question 12

Atrioventricular septal defect (AVSD)

• Clinical features
• Investigations
• Management

Answer 12

• Most commonly seen in Down syndrome (trisomy 21)
• Signs
  
  • Cyanosis at birth
  • Breathless at 2-3 weeks (HF)
• Investigations
  
  • Presentation on antenatal ultrasound screening
  • Echo
• Management
  
  • Heart failure
    
    • Diuretics + Captopril
  • Surgical correction

Question 13

Pulmonary stenosis (congenital)

• Clinical features
• Investigations
• Management

Answer 13

• Signs
  
  • Usually asymptomatic
  • Systolic murmur (ULSE)
  • No thrill
• Investigations
  
  • CXR
    
    • Normal
    • Post-stenotic dilatation of pulmonary artery
  • ECG
    
    • RVH (upright T wave in V1)
• Management
  
  • Balloon dilatation

Question 14

Aortic stenosis (congenital)

• Clinical features
• Investigations
• Management

Answer 14

• Symptoms
  
  • Asymptomatic
  • ↓ exercise tolerance
  • Chest pain on exertion
  • Syncope
• Signs
  
  • Ejection systolic murmur (URSE, radiating to carotid)
  • Weak, slow rising pulse
  • Carotid thrill (always)
• Investigations
  
  • CXR
    
    • Normal
    • Prominent LV + post-stenotic dilatation of the aorta
  • ECG
    
    • LVH
• Management
  
  • Balloon dilatation

Question 15

Coarctation of the aorta

• Clinical features
• Investigations
• Management

Answer 15

• Signs
  
  • Asymptomatic
  • ↑ BP in right arm
  • Radio-femoral delay
  • Absent foot pulses
  • Systolic murmur (LSE)
  • Continuous murmur at the back (collaterals)
• Investigations
  
  • CXR
    
    • ‘Rib notching’ due to development of large collateral intercostal arteries (red arrows)
    • ‘3’ sign, with visible notch in the descending aorta at the site of coarctation
  • ECG
    
    • LVH
• Management
  
  • Stent insertion
  • Surgery