The role of neovascularisation in the resolution of venous thrombus

Bijan Modarai; Kevin Guiver Burnand; Julia Humphries; Matthew Waltham; Alberto Smith

doi:10.1160/TH04-09-0596

Thrombosis and Haemostasis, Table of Contents

Thromb Haemost 2005; 93(05): 801-809
DOI: 10.1160/TH04-09-0596

Review Article

Schattauer GmbH

The role of neovascularisation in the resolution of venous thrombus

Authors

Bijan Modarai

¹Academic Department of Surgery, Cardiovascular Division, St Thomas’ Hospital, King’s College, London, UK
Kevin Guiver Burnand

¹Academic Department of Surgery, Cardiovascular Division, St Thomas’ Hospital, King’s College, London, UK
Julia Humphries

¹Academic Department of Surgery, Cardiovascular Division, St Thomas’ Hospital, King’s College, London, UK
Matthew Waltham

¹Academic Department of Surgery, Cardiovascular Division, St Thomas’ Hospital, King’s College, London, UK
Alberto Smith

¹Academic Department of Surgery, Cardiovascular Division, St Thomas’ Hospital, King’s College, London, UK

Abstract

Summary

Deep vein thrombosis (DVT) can give rise to chronic debilitating complications, which are expensive to treat. Anticoagulation, the standard therapy for DVT, prevents propagation, but does not remove the existing thrombus, which undergoes slow natural resolution. Alternative forms of treatment that accelerate resolution may arise from a better understanding of the cellular and molecular pathways that regulate the natural resolution of thrombi. This review will outline our current understanding of the mechanisms of thrombus resolution and the role of neovascularisation in this process. Novel experimental treatments that may one day find clinical use are also discussed. The process of thrombus resolution resembles wound healing. The mainly monocytic inflammatory infiltrate, which develops, is associated with the appearance of vascular channels. These cells may drive resolution by encouraging angiogenesis, which contributes to restoration of the vein lumen. Significant numbers of bone marrow-derived progenitor cells have also been found in naturally resolving thrombi, but their precise phenotype and their role in thrombus recanalisation is unclear. Enhanced thrombus neovascularisation and rapid vein recanalisation have been achieved in experimental models with proangiogenic agents. Recent reports of the role of bone marrow-derived progenitor cells in the revascularisation of ischaemic tissues suggest that it may be possible to obtain the same effect by delivering pluripotent or lineage specific stem cells into thrombus. These cells could contribute to thrombus recanalisation by expressing a variety of proangiogenic cytokines or by lining the new vessels that appear within the thrombus.

Keywords

Deep vein thrombosis - angiogenesis - gene therapy

Full Text

References

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