Makindo Medical Notes

Related Subjects: |Pulmonary Stenosis |Pulmonary Regurgitation |Pulmonary Hypertension |Tricuspid Stenosis |Pulmonary Embolism |Carcinoid Heart Disease

📖 About

• Carcinoid Heart Disease (CHD) is due to prolonged exposure to circulating serotonin (5-HT) and other vasoactive substances from carcinoid tumours. 🧪
• Primarily affects the right heart (tricuspid & pulmonary valves) → leaflet thickening, retraction, fibrosis → regurgitation or stenosis.
• Occurs in up to 50% of patients with carcinoid syndrome, especially with liver metastases (since normally the liver metabolises serotonin). ⚠️

🧬 Aetiology

• Tricuspid Valve → Regurgitation most common (leaflet thickening + retraction). 🔁
• Pulmonary Valve → Often stenosed due to fibrotic narrowing. 🚪
• Left-sided valves → Rare, unless right-to-left shunt (e.g. PFO) allows serotonin to bypass the lungs. 🌬️

🩺 Clinical Features

• Right-sided heart failure:
  • Dyspnoea, fatigue 🏃
  • Peripheral edema 🦶
  • Ascites, abdominal distension 💧
• Carcinoid syndrome symptoms:
  • Flushing of face/upper chest 🔴
  • Profuse diarrhoea, cramping 💩
  • Triggered by food, alcohol, stress 🍷

🔍 Investigations

• Echocardiogram (gold standard):
  • Thickened, retracted tricuspid/pulmonary leaflets
  • Severe TR + pulmonary stenosis
  • Right heart enlargement 🫀
• Biochemical markers:
  • ↑ 24-hour urinary 5-HIAA (serotonin metabolite)
  • ↑ Chromogranin A
• CT/MRI → for primary tumour & liver metastases. 🩻

🧪 Pathology

• Endocardial plaque-like fibrous thickening → restricted leaflet motion.
• Valve dysfunction = regurgitation (TS/TR) or stenosis (PS).
• Right-sided predominance (tricuspid + pulmonary). Left-sided only if shunt present.

💊 Management

• Medical:
  • Somatostatin analogues (octreotide, lanreotide) → ↓ serotonin release → less flushing/diarrhoea 🌙
  • Diuretics → control fluid overload 💧
• Interventional:
  • Valve replacement (bioprosthetic preferred to avoid thrombosis) 🛠️
  • Debulking liver mets (resection or embolisation) → ↓ serotonin production 🏥

📚 References

• AHA: Carcinoid Heart Disease Overview
• ESC: Carcinoid Heart Disease Management

Cases — Carcinoid Heart Disease (CHD)

• Case 1 — Classic Carcinoid Syndrome with Right-Sided Lesions 🦐: A 58-year-old man with flushing, diarrhoea, and bronchospasm develops progressive ankle swelling and fatigue. Exam: elevated JVP with prominent ‘v’ waves, pansystolic murmur at the left lower sternal edge, hepatomegaly, and ascites. Echo: severe tricuspid regurgitation and pulmonary stenosis due to thickened, retracted leaflets. Diagnosis: Carcinoid syndrome with right-sided valvular lesions. Management: Octreotide for carcinoid syndrome, diuretics for right heart failure, surgical valve replacement if severe symptomatic disease.
• Case 2 — Isolated Pulmonary Valve Disease 🌬️: A 62-year-old woman with known midgut neuroendocrine tumour presents with exertional dyspnoea and peripheral oedema. Exam: early diastolic murmur at the pulmonary area, parasternal heave. Echo: pulmonary regurgitation and stenosis due to plaque-like deposits on pulmonary valve. Diagnosis: Pulmonary valve involvement in carcinoid heart disease. Management: Control of tumour with somatostatin analogues; valve replacement if right ventricular dysfunction develops.
• Case 3 — Left-Sided Involvement (Uncommon) ❤️: A 65-year-old man with bronchial carcinoid tumour (not filtered by liver) develops progressive dyspnoea and orthopnoea. Exam: mid-diastolic murmur at the apex, early diastolic murmur at the aortic area. Echo: carcinoid-related thickening of mitral and aortic valves causing regurgitation. Diagnosis: Left-sided carcinoid valvular disease due to bronchial primary (bypassing hepatic metabolism). Management: Somatostatin analogues for tumour control, surgical replacement of affected valves, multidisciplinary oncology + cardiology input.

Teaching Commentary 🧠

Carcinoid heart disease = endocardial fibrosis from serotonin and vasoactive substances secreted by carcinoid tumours. - Typically affects right-sided valves (tricuspid regurgitation, pulmonary stenosis/regurgitation). - Left-sided lesions occur if serotonin bypasses hepatic metabolism (bronchial carcinoid or PFO). - Suspect in patients with carcinoid syndrome (flushing, diarrhoea, bronchospasm) who develop right heart failure signs. Dx: Echocardiography + raised urinary 5-HIAA. Mx: Tumour control (somatostatin analogues, surgery, PRRT), diuretics, valve replacement when symptomatic.