Parenteral prostanoids for severe Group 3 pulmonary hypertension with right ventricular dysfunction

Area of Science:

• Cardiology
• Pulmonology
• Pharmacology

Background:

• Group 3 pulmonary hypertension (PH) is a frequent complication of lung diseases, lacking FDA-approved treatments.
• Existing data on using Group 1 PH therapies for Group 3 PH is conflicting, with some suggesting benefits in severe cases with right ventricular (RV) dysfunction.

Purpose of the Study:

• To evaluate the efficacy of parenteral prostanoids in patients with severe Group 3 PH and RV dysfunction.
• To assess changes in prognostic markers, exercise capacity, and functional class following prostanoid therapy.

Main Methods:

• Retrospective cohort study of 9 patients with severe Group 3 PH and RV dysfunction treated with parenteral prostanoids (2007-2018).
• Severe PH defined by mean pulmonary arterial pressure (mPAP) ≥35 mmHg or mPAP 25-34 with cardiac index (CI) <2.4 L/min/m².
• Prognostic markers (NT-proBNP, 6MWD, WHO FC, oxygen needs, saturation, RVSP, RHC pressures) were measured before and after therapy.

Main Results:

• No significant improvement in NT-proBNP, exercise capacity, or functional class was observed.
• Resting oxygen requirement increased (4 to 6 L/min, P=0.04) and exertional oxygen saturation worsened (90% to 83%, P=0.01).
• Outcomes were heterogeneous; while some patients stabilized or underwent transplantation, most remained symptomatic, with three discontinuing therapy for hospice care.

Conclusions:

• Parenteral prostanoids did not yield statistically significant improvements in key clinical outcomes for Group 3 PH patients.
• Worsening oxygen requirements and saturation suggest these therapies may not be suitable for this population.
• The study advises against the general use of parenteral prostanoids in treating Group 3 PH with RV dysfunction.