TOPLINE:

In patients with pulmonary arterial hypertension (PAH), the use of anticoagulants was not associated with improvement in overall survival, and these results were confirmed by an updated meta-analysis.

METHODOLOGY:

• Investigators examined data of 1597 patients diagnosed with PAH between 2009 and 2020 from a French registry to assess whether the use of anticoagulants was associated with overall survival; 380 of these patients had been prescribed anticoagulants.
• PAH was defined as having a mean pulmonary artery pressure of ≥ 25 mm Hg, a pulmonary capillary wedge pressure of ≤ 15 mm Hg, and pulmonary vascular resistance > 3 WU. Subgroups of PAH included idiopathic/heritable PAH or PAH associated with anorexigens, PAH associated with connective tissue disease, and PAH due to repaired congenital disease.
• Adjustments based on propensity scores yielded a pseudopopulation of 1591 patients who received anticoagulants (mean age, 61.4 years; 33.6% men) and 1598 patients who did not (mean age, 61.6 years; 34.3% men).
• The primary outcome was overall survival, tracked over a minimum follow-up period of 3 years.
• Investigators conducted an updated meta-analysis that pooled five prior prospective nationwide studies with the current registry analysis.

TAKEAWAY:

• The analysis found a median survival of 5.62 years for patients receiving anticoagulants and 5.37 years for those not receiving anticoagulants, with no significant difference between the groups.
• Idiopathic/heritable PAH associated with anorexigens accounted for about 64.1%-65.0% of cases of PAH. The use of anticoagulants was not associated with survival in either patients with idiopathic/heritable PAH associated with anorexigens or those with PAH associated with connective tissue disease.
• The updated meta-analysis found no association between anticoagulant therapy and survival in the overall group or key subgroups of PAH; the pooled analysis showed heterogeneity (I² = 65%).

IN PRACTICE:

“Despite a strong pathophysiological rationale supporting the use of anticoagulant therapy in PAH, our analysis, based on a large national registry and integrated into an updated meta-analysis of contemporary registry data, did not show an association between anticoagulant use and improved survival outcomes,” the investigators reported.

“The study is to be commended strongly as important work with direct clinical relevance to a treatment decision that clinicians managing PAH patients face regularly. The field is, however, left to reconcile pathological and pathophysiological observations implicating thrombosis in PAH that do not seem to match clinical research on the use of anticoagulation to mitigate adverse outcome,” experts wrote in an editorial comment accompanying the journal article.

SOURCE:

This study was led by Laurent Bertoletti, MD, PhD, of CHU Saint-Étienne in Saint-Étienne, France. It was published online on September 22, 2025, in the Journal of the American College of Cardiology.

LIMITATIONS:

The use of anticoagulants was recorded only when the patients were included in the registry, which might have changed during the follow-up. This study did not account for the type and dosage of anticoagulants or the indicators of quality of treatment. The findings may not apply to other forms of PAH such as portopulmonary hypertension.

DISCLOSURES:

Several authors reported receiving institutional research support, honoraria for speaking or consulting, and support for attending meetings from various pharmaceutical and healthcare companies, including Bayer and Merck Sharp & Dohme, Bayer, and AstraZeneca.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.