-transparent.png){kind=logo}
Differences in aortic impedance between normotensives and hypertensives are not well characterized. We examined impedance in 8 normotensive and 11 hypertensive (mean 96.7 vs. 122.2 mmHg) age-matched, Chinese patients undergoing cardiac catheterization at rest, during nitroprusside, and handgrip exercise before and after beta blockade (propranolol). Hypertensives had higher resistance (2,295 vs. 1713 dyn-s/cm5), characteristic impedance (145.7 vs. 93.9 dyn-s/cm5), total external power (1,579 vs. 1174 mW), peripheral reflections (ratio of backward to forward wave components of 0.54 vs. 0.44), and first zero crossing of impedance phase angle (4.15 vs. 2.97 Hz). These abnormalities were eliminated with vasodilatation. Differences between groups were not further exacerbated when pressure was increased during handgrip exercise. Beta blockade further increased resistance and reflections. Thus, hemodynamic abnormalities of essential hypertension (increased resistance, reflections, and pulse wave velocity, and decreased compliance) are compatible with an increased vasomotor tone that is further unmasked during generalized beta blockade.
C T Ting, and
K P Brin, and
S J Lin, and
S P Wang, and
M S Chang, and
B N Chiang, and
F C Yin
January 1972,
Bollettino della Societa italiana di cardiologia,
C T Ting, and
K P Brin, and
S J Lin, and
S P Wang, and
M S Chang, and
B N Chiang, and
F C Yin
October 1970,
Circulation research,
C T Ting, and
K P Brin, and
S J Lin, and
S P Wang, and
M S Chang, and
B N Chiang, and
F C Yin
September 1991,
Circulation,
C T Ting, and
K P Brin, and
S J Lin, and
S P Wang, and
M S Chang, and
B N Chiang, and
F C Yin
January 1990,
Revista espanola de cardiologia,
C T Ting, and
K P Brin, and
S J Lin, and
S P Wang, and
M S Chang, and
B N Chiang, and
F C Yin
December 1954,
Archives des maladies du coeur et des vaisseaux,
C T Ting, and
K P Brin, and
S J Lin, and
S P Wang, and
M S Chang, and
B N Chiang, and
F C Yin
January 1962,
Minerva nefrologica,
C T Ting, and
K P Brin, and
S J Lin, and
S P Wang, and
M S Chang, and
B N Chiang, and
F C Yin
May 1997,
Minerva cardioangiologica,
C T Ting, and
K P Brin, and
S J Lin, and
S P Wang, and
M S Chang, and
B N Chiang, and
F C Yin
December 1995,
Angiology,
C T Ting, and
K P Brin, and
S J Lin, and
S P Wang, and
M S Chang, and
B N Chiang, and
F C Yin
August 1970,
The American journal of cardiology,
C T Ting, and
K P Brin, and
S J Lin, and
S P Wang, and
M S Chang, and
B N Chiang, and
F C Yin
December 1993,
Hypertension (Dallas, Tex. : 1979),
