Cor Pulmonale

Question 1

What is cor pulmonale?

Answer 1

Right heart failure caused by chronic pulmonary arterial hypertension.

Question 2

What are the causes of cor pulmonale

Answer 2

Lung disease: COPD, lung fibrosis, bronchiectasis and severe chronic asthma

Pulmonary vascular disease: pulmonary embolism, pulmonary vasculitis, primary pulmonary hypertension and sickle-cell disease

Thoracic cage abnormalities: kyphosis, scoliosis and thoracoplasty

Neuromuscular disease: mysthaenia gravis and motor neurone disease

Question 3

Briefly describe the pathophysiology of cor pulmonale

Answer 3

Right ventricular hypertrophy, dilation and/ or dysfunction due to pulmonary hypertension secondary to pulmonary disease, upper airway obstruction or chest wall abnormalities.

Question 4

Why does peripheral oedema occur in cor pulmonale?

Answer 4

Increased pulmonary vascular resistance → increased pulmonary circuit afterload → increased right ventricular workload → right ventricular hypertrophy or dilation → impaired right ventricular function and failure → increased right arterial pressure → fluid back-up into venous system

Question 5

What risk factors are associated with cor pulmonale?

Answer 5

• Presence of parenchymal or vascular lung disease, COPD
• Smoking

Question 6

What are the signs of cor pulmonale?

Answer 6

• Cyanosis
• Tachycardia
• Raised JVP with prominent a and v waves
• RV heave
• Loud P2
• Pansystolic murmur (tricuspid regurgitation)
• Hepatomegaly
• Oedema

Question 7

What are the symptoms of cor pulmonale?

Answer 7

• Dyspnoea
• Fatigue
• Syncope

Question 8

What investigations should be ordered for cor pulmonale?

Answer 8

• FBC
• ABG
• CXR
• ECG
• Echocardiography

Question 9

Why investigate using FBC? And what may this show?

Answer 9

• Raised haematocrit and haemoglobin (secondary polycythaemia)

Question 10

Why investigate using ABG? And what may this show?

Answer 10

• Hypoxia with or without hypercapnia

Question 11

Why investigate using CXR? And what may this show?

Answer 11

• Visualises right atria and ventricle
• Hypertrophy and distension of pulmonary vasculature

Question 12

Briefly describe what can be seen on the CXR of cor pulmonale

Answer 12

• Right sided hypertrophy therefore loss of cardiac silhouette
• Prominent pulmonary arteries

Question 13

Why investigate using ECG? And what may this show?

Answer 13

• P pulmonale, right axis deviation and right tricular hypertrophy or strain

Question 14

Why investigate using echocardiography? And what may this show?

Answer 14

• Detects structural and functional changes of the right ventricle
• Hypertrophy; dilation of the right heart ventricle; dilation of the coronary sinus and stimation of pulmonary arterial pressure

Question 15

How is respiratory failure treated in cor pulmonale?

Answer 15

In the acute situation give 24% oxygen if P_aO₂ <8 kPa. Monitor ABG and gradually increase O₂ concentrations if P_aCO₂ is stable.

Question 16

How is cardiac failure treated in cor pulmonale?

Answer 16

Loop diuretic use (e.g. furosemide). Alternative spironolactone.

Question 17

When is heart-lunfg transplant considered in cor pulmonale?

Answer 17

If the patient is young or has resistant cor pulmonale.

Question 18

What are the complications of cor pulmonale?

Answer 18

• RV failure
• Liver dysfunction