📋 MOCK OSCE · FCPS, MCPS, MD PAEDIATRICS ⏱ 10 min · AORTIC STENOSIS

Aortic Stenosis · Short Case

Candidate task: perform focused cardiovascular examination on a child with suspected aortic stenosis.
Then discuss differential diagnosis, investigations, management & follow‑up.
Pre‑exam Protocol
⏤ · Wash, Warm, Introduce, Position, Expose, Approach ▾

Standard pre‑examination protocol – must be demonstrated:

🖐 Wash hands with sterilizing solution.
🔥 Warm hands and stethoscope.
👋 Introduce yourself to child & parent.
🧍 Position child: supine, sitting, then leaning forward (to accentuate aortic murmurs).
👕 Exposure — chest fully exposed, warm environment.
➡️ Approach from the right side.
✔ CPSP marker: Pre‑exam Protocol is observed and scored.
1. Clinical Examination (≈6 min)
02 General Look (Inspection from end of bed) ▾

Key observations:

  • Colour: pallor (low cardiac output – severe AS), cyanosis (rare).
  • Respiratory rate: tachypnoea (heart failure – critical AS in neonate).
  • Precordial bulge: chronic LV enlargement (severe AS).
  • Nutritional status: failure to thrive (severe AS).
  • Dysmorphic features: Williams syndrome (supravalvular AS + elfin facies).
  • Activity: exercise intolerance, chest pain, syncope (classic triad).
👁 Red flags: systolic ejection murmur at right upper sternal border + ejection click + radiation to carotids → AS.
03 Precordium & Cardiovascular Examination ▾

Systematic cardiovascular exam:

  • Inspection: scars (previous surgery), chest asymmetry, apex beat visible.
  • Palpation: apex displaced laterally (LVH), thrills at right upper sternal border and suprasternal notch.
  • Auscultation: S1 normal, S2 may be single (if severe), systolic ejection murmur at right upper sternal border (RUSB) radiating to carotids, ejection click (if valvular).
  • Additional: S4 (if severe, decreased LV compliance).
  • Positional changes: squatting → murmur decreases (increased venous return).
🔍 Key: systolic ejection murmur at RUSB + ejection click + radiation to carotids + LVH → AS.
04 General Physical Exam (Hands → Face → Chest → Limbs) ▾

Systematic examination:

  • Hands: clubbing (if cyanotic heart disease), capillary refill time.
  • Face: mucous membrane colour, dental caries (SBE risk).
  • Chest: auscultate lung fields (crackles – heart failure).
  • Pulses: weak, slow-rising (pulsus parvus et tardus) – hallmark of severe AS.
  • Blood pressure: 4‑limb BP (exclude coarctation).
  • Lower limbs: oedema (right heart failure – late).
📏 Anthropometry: weight, length – plot growth.
05 Developmental Assessment & Associated Signs ▾

Assess:

  • Motor milestones: may be delayed (chronic low cardiac output).
  • Growth: failure to thrive (severe AS).
  • Syndromic: Williams syndrome (supravalvular AS + elfin facies + intellectual disability).
  • Eyes: stellate iris (Williams).
  • Neurological: syncope (exercise-induced).
🧠 Genetic clues: supravalvular AS + elfin facies + hypercalcaemia → Williams syndrome (7q11.23 deletion).

📋 Case Presentation – (fill in during exam)

This is a _____-year-old _____ child, referred for _____ (murmur / chest pain / syncope). On examination, the child appears _____ (well/unwell/lethargic), with _____ (tachypnoea / pallor / oedema). Precordial inspection: _____ (bulge / scar). Palpation: _____ (apex displaced / thrill). Auscultation: S1 _____, S2 _____, murmur _____ (systolic ejection) at _____ (right upper sternal border) radiating to _____ (carotids). Additional: ejection click _____ (present / absent). Pulses: _____ (weak/slow-rising). BP: _____. Growth: weight _____ percentile, length _____ percentile. Associated signs: _____.

2. Viva Discussion (≈4 min)
06 Viva · Differential, Investigations, Management, Follow‑up ▾
🔹 Differential Diagnosis

• Valvular aortic stenosis – most common, bicuspid valve
• Subvalvular aortic stenosis – fixed membrane, dynamic (HCM)
• Supravalvular aortic stenosis – Williams syndrome
• Coarctation of aorta – femoral pulses, hypertension
• Hypertrophic cardiomyopathy – dynamic obstruction, S4
• Innocent murmur – no other signs
• Pulmonary stenosis – ejection click at LUSB, no carotid radiation
• VSD – holosystolic murmur at LLSB
• Mitral regurgitation – apical holosystolic

🔹 Investigations – Diagnosis

• Echocardiography: 2D + Doppler – valve morphology, peak/mean gradient, LV thickness, valve area.
• Chest X‑ray: cardiomegaly (LV), post‑stenotic dilation of aorta.
• ECG: LVH, LV strain (ST‑T changes), LAD.
• Cardiac catheterisation: if gradient >50 mmHg, or for balloon valvuloplasty.
• Exercise testing: to assess symptoms and blood pressure response.

🔹 Investigations – Aetiology

• Genetic: FISH for 7q11.23 (Williams syndrome).
• Karyotype: Turner syndrome (bicuspid aortic valve).
• Echocardiography: to differentiate valvular, subvalvular, supravalvular.

🔹 Investigations – Exclude Others

• Echocardiography: differentiate from HCM (SAM, LVOT obstruction).
• CXR: differentiate from coarctation (rib notching).
• ECG: differentiate from HCM (deep Q waves).

🔹 Investigations – Rule Out Complications

• Echocardiography: LV dysfunction, aortic regurgitation, endocarditis.
• Holter: arrhythmias (VT, sudden death risk).
• Exercise testing: to assess symptoms and blood pressure response.
• Blood cultures: if infective endocarditis suspected.

🔹 Management – Across Organ Systems

Medical (Neonatal)

Prostaglandin E1 (duct‑dependent), careful fluid management.

Heart Failure

Diuretics, ACE inhibitors – but avoid in severe AS (afterload reduction can cause hypotension).

Nutrition

High‑calorie feeds if failure to thrive.

Infective Endocarditis

Prophylaxis recommended for prosthetic valves and unrepaired AS (AHA 2007).

Exercise Restriction

No competitive sports if severe AS (gradient >40 mmHg).

Balloon Valvuloplasty

First‑line for valvular AS (especially neonates and children).

Surgical

Valvotomy (neonates/infants), Ross procedure, or valve replacement (older children).

Genetic Counselling

Recurrence risk ~3‑4% (isolated); higher if syndromic.

📈 Prognosis

  • Mild AS: excellent prognosis; may progress.
  • Moderate AS: monitor for progression; may require intervention.
  • Severe AS: risk of sudden death, heart failure, syncope.
  • Post‑valvuloplasty: 80‑90% success; restenosis may occur.
  • Post‑surgical: excellent outcomes; need lifelong follow‑up.

📋 Follow‑up Schedule

  • Mild AS: annual cardiology review.
  • Moderate AS: 6‑12 monthly with echocardiography.
  • Severe AS: 3‑6 monthly; consider intervention.
  • Post‑intervention: 6‑12 monthly for 1‑2 years, then annually.
  • Lifelong: follow‑up (adult congenital cardiology).
💡 Examiner expectation: logical differential (valvular vs subvalvular vs supravalvular), systematic investigation (diagnosis → aetiology → exclude others → complications), and a management plan covering balloon valvuloplasty, surgical options, and exercise restriction. Know the classic triad: chest pain, syncope, and dyspnoea.
📚 Visit paeds.online for more CPSP resources
Mock OSCE · Aortic Stenosis · Based on Wyne‑Harris, Nelson & Pediatric Clinical Advisor