Related Experiment Video
Updated: Dec 13, 2025

Increasing Pulmonary Artery Pulsatile Flow Improves Hypoxic Pulmonary Hypertension in Piglets
Published on: May 11, 2015
Evidence synthesis in pulmonary arterial hypertension: a systematic review and critical appraisal
Max Schlueter1, Amélie Beaudet2, Evan Davies2
1IQVIA, 210 Pentonville Road, London, N1 9JY, UK. max.schlueter@iqvia.com.
Background:
The clinical landscape of pulmonary arterial hypertension (PAH) has evolved in terms of disease definition and classification, trial designs, available therapies and treatment strategies as well as clinical guidelines. This study critically appraises published evidence synthesis studies, i.e. meta-analyses (MA) and network-meta-analyses (NMA), to better understand their quality, validity and discuss the impact of the findings from these studies on current decision-making in PAH.
Methods:
A systematic literature review to identify MA/NMA studies considering approved and available therapies for treatment of PAH was conducted. Embase, Medline and the Cochrane's Database of Systematic Reviews were searched from database inception to April 22, 2020, supplemented by searches in health technology assessment websites. The International Society for Pharmacoeconomics and Outcomes Research (ISPOR) checklist covering six domains (relevance, credibility, analysis, reporting quality and transparency, interpretation and conflict of interest) was selected for appraisal of the included MA/NMA studies.
Results:
Fifty-two full publications (36 MAs, 15 NMAs, and 1 MA/NMA) in PAH met the inclusion criteria. The majority of studies were of low quality, with none of the studies being scored as 'strong' across all checklist domains. Key limitations included the lack of a clearly defined, relevant decision problem, shortcomings in assessing and addressing between-study heterogeneity, and an incomplete or misleading interpretation of results.
Conclusions:
This is the first critical appraisal of published MA/NMA studies in PAH, suggesting low quality and validity of published evidence synthesis studies in this therapeutic area. Besides the need for direct treatment comparisons assessed in long-term randomized controlled trials, future efforts in evidence synthesis in PAH should improve analysis quality and scrutiny in order to meaningfully address challenges arising from an evolving therapeutic landscape.
Related Concept Videos
Pulmonary Hypertension: Classification and Pathogenesis
There are various classifications for PH, each relating to different underlying causes and also...
Treatment for Pulmonary Arterial Hypertension: Endothelin Receptor Antagonists
ETs are synthesized through a complex sequence of enzymatic steps, primarily involving an enzyme referred to as endothelin-converting enzyme...
Treatment for Pulmonary Arterial Hypertension: Oxygen Therapy for Respiratory Failure
Oxygen therapy is vital in increasing and maintaining blood oxygen levels in PAH patients. As a result, it aids in reducing fatigue,...
Treatment for Pulmonary Arterial Hypertension: Receptor Tyrosine Kinase Inhibitors and Calcium Channel Blockers
TKIs, such as imatinib (Gleevec), are particularly effective in tackling the growth and mitogenic factors that become upregulated in PAH patients. These factors contribute to the...
Treatment for Pulmonary Arterial Hypertension: Prostacyclin Receptor Agonists
These agonists bind to the IPR receptor situated on the plasma membrane of the pulmonary artery smooth muscle cells. This binding triggers a cascade of reactions known as the GS-AC-cAMP-PKA pathway. This pathway results in the relaxation of smooth muscle...
Treatment for Pulmonary Arterial Hypertension: Phosphodiesterase Inhibitors
Among the PDE5 inhibitors, sildenafil (Revatio) stands out as a competitive and selective inhibitor. It operates by elevating cellular levels of cGMP and augmenting signaling through the cGMP-PKG pathway, promoting vasodilation. Upon oral...

