Pulmonary HTN

Question 1

What is pulmonary hypertension?

Answer 1

Pulmonary hypertension is increased resistance and pressure of blood in the pulmonary arteries. Increasing the pressure and resistance in the pulmonary arteries causes strain on the right side of the heart trying to pump blood through the lungs. This also causes a back pressure of blood into the systemic venous system.

Question 2

What are the causes of pulmonary hypertension?

Answer 2

The causes of pulmonary hypertension can split into 5 groups:

Group 1 – Primary pulmonary hypertension or connective tissue disease such as systemic lupus erythematous (SLE)
Group 2 – Left heart failure usually due to myocardial infarction or systemic hypertension
Group 3 – Chronic lung disease such as COPD
Group 4 – Pulmonary vascular disease such as pulmonary embolism
Group 5 – Miscellaneous causes such as sarcoidosis, glycogen storage disease and haematological disorders

Question 3

What are the signs pulmonary hypertension?

Answer 3

Shortness of breath is the main presenting symptom.

Other signs and symptoms are:

• Syncope
• Tachycardia
• Raised JVP
• Hepatomegaly
• Peripheral oedema.

Question 4

Investigations of pulmonary hypertension?

Answer 4

ECG Changes

The right sided heart strain causes ECG changes such as:

• Right ventricular hypertrophy seen as larger R waves on the right sided chest leads (V1-3) and S waves on the left sided chest leads (V4-6)
• Right axis deviation
• Right bundle branch block

Chest Xray Changes

• Dilated pulmonary arteries
• Right ventricular hypertrophy

Other investigations

• A raised NT-proBNF blood test result indicates right ventricular failure
• Echo can be used to estimate pulmonary artery pressure

Question 5

Management of primary pulmonary hypertension

Answer 5

Primary pulmonary hypertension can be treated with:

• IV prostanoids (e.g. epoprostenol)
• Endothelin receptor antagonists (e.g. macitentan)
• Phosphodiesterase-5 inhibitors (e.g. sildenafil)

Supportive treatment for complications such as respiratory failure, arrhythmias and heart failure.

Question 6

Prognosis of pulmonary hypertension

Answer 6

The prognosis is quite poor with a 30-40% 5 year survival from diagnosis. This can increase to 60-70% where specific treatment is possible.

Question 7

Management of secondary pulmonary hypertension

Answer 7

Secondary pulmonary hypertension is managed by treating the underlying cause such as pulmonary embolism or SLE.