Related Experiment Videos
Peripheral vascular changes and ambulatory blood pressure profiles
D Duprez1, M De Buyzere, J De Sutter
1Department of Cardiology and Angiology, University Hospital, Gent, Belgium.
American Journal of Hypertension
|December 1, 1993
Summary
This study reveals that higher blood pressure (BP) levels correlate with reduced blood flow and impaired vasodilating capacity in both skin and muscle vessels. Essential hypertension particularly affects muscle circulation, even at moderate levels.
Area of Science:
- Cardiovascular Physiology
- Hypertension Research
- Vascular Biology
Background:
- Blood pressure (BP) regulation involves complex interactions between central and regional hemodynamics.
- Understanding regional blood flow and vascular resistance in relation to BP is crucial for diagnosing and managing hypertension.
- Previous studies have shown varying correlations between systemic BP and peripheral circulation.
Purpose of the Study:
- To correlate casual and 24-hour ambulatory BP measurements with regional (calf and finger) blood flow and vascular resistance.
- To investigate changes in vasodilating capacity across a spectrum of BP levels, from low to hypertensive.
- To identify differences in vascular response between muscle and skin circulation in relation to BP.
Main Methods:
- Simultaneous measurement of calf and finger blood flow using ECG-triggered venous occlusion plethysmography in 75 subjects.
- Correlation analysis between BP (casual and ambulatory) and regional vascular resistance/blood flow at rest and during reactive hyperemia.
- Adjustment for age-related changes in BP to isolate the effects of BP on vascular function.
Main Results:
- Significant correlations were found between calf/finger vascular resistance and both casual and ambulatory BP across the entire BP range.
- Skin blood flow was consistently higher than muscle blood flow at all BP levels, both at rest and after occlusion.
- A progressive decrease in vasodilating capacity was observed with increasing BP in both muscle and skin vessels.
- Borderline to moderate essential hypertensives showed significantly reduced muscle blood flow post-occlusion compared to normotensives, while skin circulation remained preserved.
Conclusions:
- Regional vascular resistance, particularly in muscle and skin, is significantly associated with both casual and ambulatory BP measurements.
- Vasodilating capacity diminishes progressively with increasing BP, affecting both muscle and skin circulations.
- Muscle vascular beds appear more vulnerable to the effects of essential hypertension than skin vascular beds, showing reduced reactive hyperemia even at moderate BP levels.