Makindo Medical Notes

Related Subjects: |Pulmonary Stenosis |Pulmonary Hypertension |Pulmonary Embolism

🫀 About

• Pulmonary valve stenosis is a rare obstruction of right ventricular outflow, restricting blood flow to the pulmonary artery. Severe cases can lead to right heart failure and cyanosis.
• Most cases are congenital, but acquired forms occur (e.g., carcinoid, rheumatic disease, radiation).

⚠️ Causes

• Congenital:
  • Isolated pulmonary valve stenosis (commonest congenital form).
  • Part of syndromes: Fallot’s Tetralogy, Noonan, Turner, William’s, congenital rubella.
• Acquired:
  • Rheumatic heart disease (rare at pulmonary valve).
  • Carcinoid heart disease (serotonin effect on right heart valves).
  • Infective endocarditis (rare pulmonary valve involvement).
  • Radiation-induced fibrosis.

🧾 Clinical Features

• Symptoms: Dyspnoea, fatigue, exertional intolerance. Severe → right heart failure (edema, ascites, hepatomegaly).
• Children may show failure to thrive, cyanosis if right-to-left shunt (ASD/PFO).

🩺 Physical Examination

• Palpable RV heave, raised JVP with prominent a wave.
• Ejection systolic murmur at left upper sternal edge, louder with inspiration.
• Ejection click after S1 (softens on inspiration → opposite to most right-sided lesions).
• Soft/absent P2 if severe (delayed/weak pulmonary closure).

🔬 Investigations

• ECG: P pulmonale, RVH, right axis deviation, ± RBBB.
• CXR: Post-stenotic dilatation of pulmonary artery, RA/RV enlargement, pulmonary oligaemia.
• Echocardiogram: Diagnostic – Doppler measures gradient across valve.
• Cardiac catheterisation: Mainly pre-intervention to assess pressures/anatomy.
• MRI: Helpful for complex CHD anatomy.

🧩 Pathophysiology

• Obstruction → ↑RV pressure → RVH.
• Severe stenosis: reduced pulmonary flow, cyanosis if R→L shunt present.
• Chronic: progressive RV dysfunction, arrhythmias, right heart failure.

💊 Management

• Conservative: Monitor mild, asymptomatic cases.
• Medical:
  • Diuretics for right HF.
  • Beta-blockers sometimes for symptomatic RV strain.
• Interventional:
  • 💉 Balloon valvuloplasty → first-line for moderate/severe valvular stenosis (gradient >50 mmHg or symptomatic).
  • 💉 Percutaneous pulmonary valve replacement (PPVR) → if failed valvuloplasty or complex anatomy.
• Surgical:
  • Pulmonary valvotomy (open valve surgically).
  • Infundibular resection for subvalvular obstruction.
  • Open-heart repair if multiple CHD defects.

📊 Follow-up & Prognosis

• Excellent long-term survival after successful intervention ✅.
• Regular echo surveillance for restenosis or RV dysfunction.
• Associated CHD → lifelong specialist follow-up.
• Endocarditis prophylaxis sometimes considered if prosthetic valve inserted.

📚 References

• AHA Guidelines on Pulmonary Valve Disease
• European Heart Journal: Congenital Heart Disease

Cases — Pulmonary Stenosis (PS)

• Case 1 — Asymptomatic Child with Incidental Murmur 👶: A 7-year-old girl attends a school medical where a systolic ejection murmur is noted at the left upper sternal edge with an ejection click. She is otherwise well, with normal growth and exercise tolerance. Diagnosis: Mild congenital pulmonary valve stenosis. Management: No immediate treatment; monitor with echocardiography; most mild cases remain stable.
• Case 2 — Young Adult with Exertional Dyspnoea 🏃: A 22-year-old man presents with breathlessness and fatigue on exertion. Exam: right ventricular heave, systolic thrill at left upper sternal edge, loud ejection systolic murmur with widely split S2. Echo: peak gradient 60 mmHg across pulmonary valve. Diagnosis: Moderate pulmonary valve stenosis with RV hypertrophy. Management: Balloon valvuloplasty (first-line); surgical valvotomy if not suitable; endocarditis prophylaxis not routinely required unless prosthetic material used.
• Case 3 — Severe PS in Neonate 🚼: A 2-day-old newborn becomes cyanotic and tachypnoeic with poor feeding. Exam: harsh systolic murmur at pulmonary area, hepatomegaly, weak femoral pulses. Echo: critical pulmonary stenosis with duct-dependent pulmonary circulation. Diagnosis: Severe critical pulmonary stenosis in neonate. Management: Prostaglandin E₁ infusion to keep ductus arteriosus open; urgent balloon valvuloplasty or surgical intervention; intensive care support.

Teaching Commentary 🧠

Pulmonary stenosis is usually congenital, due to fusion or dysplasia of the pulmonary valve leaflets. - Mild: often asymptomatic, incidental murmur. - Moderate: exertional dyspnoea, fatigue, RV hypertrophy. - Severe/Critical (infants): cyanosis, RV failure, duct-dependent circulation. Dx: Echocardiography with Doppler gradient. Mx: Balloon valvuloplasty is first-line for significant PS. Prognosis is excellent if corrected early.