What Is Angiogenesis?
Angiogenesis is the biological process through which new blood vessels form from pre-existing capillaries. It is a fundamental mechanism involved in healing, growth and the body’s adaptation to changing metabolic demands.
In pathological conditions such as chronic wounds, ischaemic disorders and radiation-induced tissue injury, angiogenesis may be inadequate or impaired. Restoring this process therefore becomes a major therapeutic objective.
In clinical practice, inadequate angiogenesis may present as delayed healing, chronic ischaemia, failure of implant osseointegration or incomplete recovery following injury. The ability to stimulate angiogenesis is one of the principal reasons why hyperbaric oxygen therapy has such a broad range of applications in vascular medicine and in the treatment of chronic pathological conditions more generally.
Characteristics of Angiogenesis
Angiogenesis is regulated by a complex network of molecular signals, with vascular endothelial growth factor (VEGF) acting as a central regulator. VEGF is released by cells exposed to hypoxic conditions and acts on capillary endothelial cells, stimulating their growth and the formation of new blood vessels.
In chronic ischaemic conditions, this mechanism is often inadequate. Despite the presence of hypoxia, angiogenesis may not proceed effectively because of depleted regenerative capacity, chronic inflammation or the absence of essential biological cofactors.
Understanding this dysfunction is crucial. Hypoxia alone is not sufficient to activate effective angiogenesis; the appropriate biological environment is also required.
Scientific Basis
Hyperbaric oxygen therapy has emerged as one of the most potent clinically available stimulators of angiogenesis. Molecular, cellular and clinical studies have shown that the alternation between hyperoxia during treatment sessions and relative hypoxia between sessions provides a powerful stimulus for the release of VEGF and other growth factors.
Histological studies of tissue samples from patients treated with hyperbaric oxygen therapy have demonstrated a significant increase in vascular density compared with control groups. This finding directly reflects induced neovascularisation and helps explain the clinical benefits observed in conditions characterised by vascular insufficiency.
Hyperbaric Oxygen Therapy and Angiogenesis
The stimulation of angiogenesis is one of the fundamental mechanisms through which hyperbaric oxygen therapy benefits a wide range of conditions.
This mechanism is particularly important in vascular indications. The formation of new blood vessels in ischaemic areas may represent the only available physiological means of improving perfusion in patients who are not candidates for vascular intervention.
Each session in the hyperbaric chamber acts as a controlled biological stimulus. Hyperoxia during treatment is followed by relative hypoxia between sessions, and this alternation represents one of the most powerful known physiological stimuli for VEGF release.
After enough sessions, the resulting formation of a new vascular network can produce a sustained improvement in oxygen delivery to the affected area.
The treatment course is determined according to the underlying vascular condition.