Ferreira-Filho S R, Dorneles H
Nephrology Division, Federal University of Uberlândia, MG Brazil.
J Hum Hypertens. 1995 Jul;9(7):535-40.
We evaluated the systemic haemodynamic alterations induced by slow-release nifedipine administered to elderly hypertensive patients, 20 mg twice daily by the oral route for 4 weeks. A non-invasive chest electrical bio-impedance method was used to detect changes in stroke volume and cardiac output. The random, double-blind, crossover study showed variations in measurements made in the supine and in the standing position: delta -18.0% (P < 0.001) and delta -14.9% (P < 0.001) for mean arterial pressure; delta -16.5% (P < 0.01) and delta -34.9% (P < 0.01) for total peripheral resistance; and delta +8.1% (P < 0.05) and delta +12.6% (P < 0.01) for heart rate, respectively. In contrast, cardiac output and stroke volume were the same when measured in the supine and standing positions both when compared with the placebo period and when compared with each other. We conclude that slow-release nifedipine is effective in reducing systemic blood pressure levels of elderly subjects and that this phenomenon occurs without reductions in cardiac output.
我们评估了老年高血压患者口服缓释硝苯地平（每日两次，每次20毫克，共4周）所引起的全身血流动力学改变。采用无创胸部电阻抗法检测每搏输出量和心输出量的变化。这项随机、双盲、交叉研究显示，仰卧位和站立位测量值存在差异：平均动脉压分别下降-18.0%（P<0.001）和-14.9%（P<0.001）；总外周阻力分别下降-16.5%（P<0.01）和-34.9%（P<0.01）；心率分别上升+8.1%（P<0.05）和+12.6%（P<0.01）。相比之下，与安慰剂期相比以及仰卧位和站立位相互比较时，心输出量和每搏输出量相同。我们得出结论，缓释硝苯地平可有效降低老年受试者的全身血压水平，且这种现象发生时心输出量并未降低。
