Treatment of Pulmonary Hypertension
The recommended treatment for pulmonary hypertension depends on classification, with initial combination therapy of ambrisentan plus tadalafil being the first-line treatment for most patients with pulmonary arterial hypertension (PAH) to improve exercise capacity and delay clinical worsening. 1
Classification and Initial Assessment
- Pulmonary hypertension (PH) is classified into five groups based on etiology, with treatment approaches differing significantly between groups 1
- Risk stratification is essential to guide therapy intensity, with parameters including clinical evidence of right ventricular failure, functional class, exercise capacity, and hemodynamics 2
- Vasoreactivity testing is recommended for patients with PAH (in the absence of contraindications) to identify the small subset who may respond to calcium channel blockers 2
Treatment Algorithm Based on PAH Classification
For Vasoreactive Patients
- High-dose calcium channel blockers are recommended for the approximately 10% of idiopathic PAH patients who demonstrate acute vasoreactivity 2
For Non-Vasoreactive Patients
Low or Intermediate Risk (WHO FC II-III):
- Initial oral combination therapy with ambrisentan and tadalafil is recommended as it has proven superior to initial monotherapy in delaying clinical failure 2, 1
- PDE-5 inhibitors (sildenafil, tadalafil) significantly improve clinical status, exercise capacity, and hemodynamics of PAH patients 3
- Tadalafil 40mg once daily has been shown to increase 6-minute walk distance and improve quality of life measures 4
High Risk (WHO FC IV):
- Initial combination therapy including intravenous prostacyclin analogues is recommended 2
- Intravenous epoprostenol should be prioritized as it has reduced the 3-month mortality rate in high-risk PAH patients 2, 5
- Treprostinil injection is indicated for the treatment of PAH to diminish symptoms associated with exercise 6
Sequential Therapy for Inadequate Response
- If clinical response to initial therapy is inadequate, sequential double or triple combination therapy is recommended 2
- The combination of riociguat and PDE-5 inhibitors is contraindicated due to risk of hypotension 2, 1
- For patients transitioning between PDE-5 inhibitors, overnight switching from sildenafil to tadalafil appears feasible without clinical deterioration 7
Supportive Measures
- Diuretic treatment is indicated in PAH patients with signs of right ventricular failure and fluid retention 2
- Continuous long-term oxygen therapy is indicated when arterial blood O2 pressure is consistently less than 8 kPa (60 mmHg) 2, 8
- Oral anticoagulation should be considered in patients with idiopathic PAH, heritable PAH, and PAH due to anorexigens 2
- Supervised exercise rehabilitation should be considered for physically deconditioned patients 2, 8
Advanced Therapies
- Lung transplantation is recommended soon after inadequate clinical response on maximal medical therapy 2, 8
- Balloon atrial septostomy (BAS) may be considered as a palliative or bridging procedure in patients deteriorating despite maximal medical therapy 2
- In emergency situations, inotropic support is recommended for hypotensive patients 2, 8
Treatment for Other PH Groups
- For Group 2 (PH due to left heart disease), treatment should focus on optimizing the underlying cardiac condition; PAH-specific therapies are not recommended 2
- For Group 4 (Chronic thromboembolic PH), pulmonary endarterectomy is the recommended treatment when feasible 2
Important Considerations
- Patients with PAH should be managed at specialized centers with expertise in pulmonary hypertension 2, 1
- Avoid abrupt cessation of prostacyclin therapy as this can lead to rebound pulmonary hypertension 6
- In emergency settings, careful volume management is imperative, especially in the setting of hypotension, as patients with right ventricular failure are often volume overloaded 9
- Intubation should be avoided if possible in patients with severe PH, as it may worsen right ventricular function 9