Circulating Biomarkers of Vascular Regeneration are not Associated with Residual Pulmonary Vascular Obstruction after Pulmonary Embolism: A Retrospective Observational Biomarker Study.

BACKGROUND: Residual pulmonary vascular obstruction (RPVO) persists in a substantial proportion of patients after acute pulmonary embolism (PE) despite adequate anticoagulation and is associated with long-term functional impairment. Angiogenesis plays a central role in thrombus resolution and vascular repair. In a recent prospective study, lower circulating CD34⁺ cell levels at follow-up were associated with the presence of RPVO, suggesting impaired regenerative and angiogenic capacity in patients with persistent perfusion defects. Whether classical circulating angiogenic biomarkers reflect this process remains unknown.

OBJECTIVE: To assess the relationship between angiogenic marker levels and the presence of RPVO ≥10% after an episode of PE.

PATIENTS AND METHODS: This single-center retrospective study included patients diagnosed with acute PE who received at least three months of anticoagulant therapy between January 1999 and June 2006. During the follow-up consultation, performed 6-12 months after PE diagnosis, patients underwent a ventilation/perfusion lung scan, and peripheral blood sampling for plasma biobanking. Angiogenic markers (VEGF-A, FGF-2, PlGF, MMP-1, MMP-8, endoglin, and endostatin) were measured in plasma samples collected at this visit. Levels were compared between patients with a perfusion defect (RPVO ≥10%) and those without (RPVO <10%) on ventilation/perfusion scintigraphy.

RESULTS: Among 126 patients evaluated 6 to 12 months after a PE diagnosis, 39 (31%) had RPVO ≥10%. Median levels of VEGF-A, FGF-2, PlGF, MMP-1, MMP-8, endostatin, and endoglin did not significantly differ between patients with RPVO ≥10% and those with RPVO <10%.

CONCLUSION: None of the angiogenic markers measured reflected the perfusion defect observed in patients.