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Updated: Jun 28, 2026
05:41
Non-invasive Assessment of Microvascular and Endothelial Function
Published on: January 29, 2013
Treatment of essential hypertension does not normalize capillary rarefaction
Guilherme Loures de Araújo Penna1, Rodrigo de Freitas Garbero, Mario Fritsch Neves
1Department of Clinical Medicine, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
Clinics (Sao Paulo, Brazil)
|October 18, 2008
Summary
Treated essential hypertension patients exhibit persistent microvascular rarefaction and reduced red blood cell velocity, indicating ongoing microcirculatory alterations despite effective blood pressure control.
Area of Science:
- Cardiovascular Research
- Microcirculation Physiology
- Hypertension Pathophysiology
Background:
- Essential hypertension is often associated with microvascular dysfunction.
- Understanding persistent microcirculatory changes after treatment is crucial for managing cardiovascular risk.
Purpose of the Study:
- To investigate if capillary rarefaction persists in treated essential hypertensive patients.
- To identify which microcirculatory alterations remain after anti-hypertensive therapy.
Main Methods:
- Nailfold videocapillaroscopy was used to assess functional capillary density in 28 hypertensive patients and 19 controls.
- Measurements included capillary densities at baseline, during reactive hyperemia, and venous congestion.
- Capillary loop diameters and red blood cell velocity were quantified.
Main Results:
- Hypertensive patients had significantly lower functional capillary density at all measurement points compared to controls.
- An estimated 25.1% structural capillary deficit was observed in hypertensive patients.
- Reduced baseline red blood cell velocity was noted in the hypertensive group.
Conclusions:
- Microvascular rarefaction persists in patients treated for essential hypertension, irrespective of therapy type.
- Reduced red blood cell velocity may contribute to increased systemic vascular resistance in hypertension.
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