The effect of drugs and stem cell therapies on established abdominal aortic aneurysms in mice: A systematic review and meta-analysis.

BACKGROUND

Effective pharmacological therapies for small abdominal aortic aneurysms (AAAs) have not been identified. Most preclinical work focuses on aneurysm initiation rather than established disease, reducing translational relevance.

METHODS

We conducted a systematic review and meta-analysis of murine studies evaluating pharmacological or stem cell-based interventions on established small AAAs. Forty-three studies met inclusion criteria, and 35 (n = 1163 mice) provided quantitative data. Aneurysms were induced using angiotensin II, calcium chloride, or elastase.

RESULTS

Anti-inflammatory agents, protease inhibitors, stem cells, antithrombotic therapies, and renin-angiotensin system inhibitors each significantly reduced aneurysm diameter. Earlier initiation of therapy enhanced intervention efficacy (R2 = 10.5%; p = 0.03). Only anti-inflammatory drugs significantly reduced rupture incidence (risk ratio 0.40; 95% CI 0.18-0.89). Risk of bias was moderate-to-high across most studies, with indications of potential publication bias.

CONCLUSION

Targeting inflammation, proteolysis, thrombosis, and vascular remodelling can attenuate progression of established small AAAs in mice, with anti-inflammatory therapy uniquely demonstrating protection against rupture.