treatment of pulmonary hypertension

Last edited 08/2022

  • Diuretics are needed to control oedema from right heart failure and home oxygen to correct hypoxia.
  • Anticoagulation is recommended in pulmonary arterial hypertension (PAH) and is essential for patients with chronic thromboembolic pulmnary hypertension (CTEPH).
    • Primary (idiopathic) pulmonary hypertension is treated with anticoagulants (because it is virtually impossible to rule out persistent micro-emboli as the cause).
  • Calcium channel blockers are indicated in a small subset of patients with idiopathic hypertension who show a vasoreactive response at right heart catheterisation.
  • In patients with group 1 pulmonary arterial hypertension (idiopathic PAH, PAH associated with connective tissue disease - predominantly seen with scleroderma) (1).
    • Specific drugs have been found to be beneficial in randomised controlled trials with improvement in symptoms, delayed disease progression and improved survival.
    • There are three main drug classes: prostanoids delivered iv, by nebuliser or subcutaneous (eg epoprostenol, iloprost, treprostinil), endothelin receptor antagonists (eg bosentan, ambrisentan), and phosphodiesterase inhibitors (eg sildenafil, tadalafil).
      • These drugs are only prescribed through the designated centres.
      • Side effects include flushing, headaches, gastro-intestinal disturbance and hypotension.
      • Endothelin receptor antagonists require monthly liver function monitoring.

CTEPH

  • Treatment of choice for patients with CTEPH is pulmonary endarterectomy (PEA) surgery.
  • Lifelong anticoagulation is also recommended; antiplatelet therapy is not an alternative.
  • Majority of patients can be cured with normalisation of pulmonary pressure following surgery with improvement in symptoms and prognosis, with a > 90% 5 year survival.
  • Patients unsuitable for pulmonary endarterectomy surgery and patients who still have residual PH following pulmonary endarterectomy surgery might be considered for treatment with the drugs described above.

Endothelin receptor antagonists

  • A systematic review concluded (1)
    • endothelin receptor antagonists probably increase exercise capacity, improve World Health Organization functional class (a measurement
      of how severe a person's pulmonary hypertension symptoms are), and may improve death rates and symptoms in people with PAH;
      however they may also increase the risk of liver damage, although this was rare.

In selected patients who have class 4 symptoms despite optimal medical therapy, bilateral lung or heart lung transplantation may be considered. The 5 year survival following transplantation is approximately 50-60%.

Notes:

  • A meta-analysis showed evidence an improvement of survival in the patients treated with the targeted therapies approved for pulmonary arterial hypertension (2).
    • With respect to the effects of the different classes of drugs (prostanoids, thromboxane synthase inhibitors, endothelin receptor antagonists, and phosphodiesterase type-5 inhibitors), no statistically significant between-group heterogeneity emerged in subgroup analyses in total mortality or between the subgroups testing each of the treatments.
  • The clinical classification of pulmonary hypertension is helpful in understanding the different aetiology and determining treatment (3):
      • Group 1 Pulmonary arterial hypertension (PAH)
        • idiopathic PAH
        • PAH associated with connective tissue disease: predominantly seen with scleroderma
      • Group 2 Left heart disease
        • PH associated with left heart dysfunction, systolic, diastolic or valve disease
      • Group 3 Lung disease
        • PH in patients with COPD or interstitial lung disease
      • Group 4 Chronic thromboembolic pulmonary hypertension
      • Group 5 Unclear and multifactorial mechanisms
        • Rare diseases.
  • World Health Organization classification functional status in primary pulmonary hypertension:
    • class I - no limitation on physical activity functional
    • class II - slight limitation functional class
    • III - pronounced limitation functional
    • class IV - inability to carry out any physical activity without symptoms.

References:

Related pages:

World Health Organization classification of functional status for primary pulmonary hypertension