[Microangiopathy in chronic venous insufficiency].

Area of Science:

• Vascular Biology
• Dermatology
• Microcirculation Research

Background:

• Chronic venous insufficiency (CVI) leads to skin changes, particularly in the medial malleolar region.
• Understanding the microvascular alterations in CVI is crucial for managing associated trophic lesions.

Purpose of the Study:

• To investigate the microvascular morphology and dynamics in patients with moderately severe venous insufficiency.
• To compare these findings with a healthy control group.
• To assess the functional response of skin microvasculature to postural changes.

Main Methods:

• Intravital fluorescence microscopy to visualize capillary morphology and leakage.
• Transcutaneous pO2 measurements to assess tissue oxygenation.
• Laser Doppler flowmetry to evaluate microvascular blood flow and response to posture changes.
• Comparison between 15 patients with venous insufficiency and 15 healthy controls.

Main Results:

• Patients exhibited significantly dilated, elongated, and winding capillaries with increased pericapillary leakage (halo effect).
• The vasoconstrictive response to postural changes remained largely intact.
• Despite normal capillary counts, transcutaneous pO2 was reduced in patients, correlating with observed microangiopathy.
• Increased flow was noted in the recumbent position due to measurement of deeper non-nutrient vessels.

Conclusions:

• Moderately severe venous insufficiency is characterized by significant microangiopathy, including capillary dilation and increased leakage.
• These microvascular changes, despite a preserved vasoconstrictive response, contribute to the development of skin trophic lesions.
• Reduced tissue oxygenation is a key consequence of the observed microcirculatory dysfunction.