Carretta R, Bardelli M, Muiesan S, Vran F, Fabris B, Fischetti F, Campanacci L
Istituto di Patologia Medica, University of Trieste, Italy.
Am Heart J. 1989 Jan;117(1):229-35. doi: 10.1016/0002-8703(89)90689-3.
Blood flow in superficial vessels was measured by means of combined two-dimensional and continuous-wave Doppler echography. In vitro validation of the technique showed precision to within 10% at flow rates greater than 300 ml/min. Assessment of common carotid artery blood flow was used to calculate vascular resistance in a single-blind, crossover study of 16 elderly patients over the age of 60 years (mean 67.7 +/- 6.5) with essential hypertension. The pulsatility index of the brachial artery was also determined. Before the study patients had previously received either placebo (twice a day) for 2 weeks or slow-release (SR) nicardipine (40 mg twice a day) for 2 months. During the study patients received a single 40 mg dose of nicardipine SR, after which mean arterial blood pressure decreased from 131 +/- 11 to 110 +/- 10 mm Hg (p less than 0.001) and from 122 +/- 13 to 108 +/- 11 mm Hg (p less than 0.001) in patients who had previously received placebo and nicardipine, respectively. Carotid vascular resistance decreased from 14.6 +/- 2.9 to 10.4 +/- 2.8 mm Hg.sec.ml-1 (p less than 0.001) and from 14.6 +/- 4.1 to 11.0 +/- 2.0 mm Hg.sec.ml-1 (p less than 0.01), respectively. The pulsatility index of the brachial artery changed from 9.4 +/- 4.4 to 9.7 +/- 8.3 and from 8.2 +/- 4.3 to 9.4 +/- 4.1, respectively (not significant). These data show that nicardipine SR reduces resistance both in the common carotid artery and in the brachial artery. Furthermore this drug appears to have an additional effect on the distensibility of the large arteries.
采用二维和连续波多普勒超声联合检查法测量浅表血管的血流。该技术的体外验证表明，在流速大于300 ml/min时，精度在10%以内。在一项针对16名60岁以上（平均67.7±6.5岁）原发性高血压老年患者的单盲交叉研究中，通过评估颈总动脉血流来计算血管阻力。同时还测定了肱动脉的搏动指数。研究前，患者曾接受安慰剂（每日两次）治疗2周或缓释硝苯地平（40 mg，每日两次）治疗2个月。研究期间，患者接受单次40 mg剂量的缓释硝苯地平，在此之后，之前接受安慰剂和硝苯地平治疗的患者平均动脉血压分别从131±11降至110±10 mmHg（p<0.001）和从122±13降至108±11 mmHg（p<0.001）。颈动脉血管阻力分别从14.6±2.9降至10.4±2.8 mmHg·sec·ml-1（p<0.001）和从14.6±4.1降至11.0±2.0 mmHg·sec·ml-1（p<0.01）。肱动脉的搏动指数分别从9.4±4.4变为9.7±8.3和从8.2±4.3变为9.4±4.1（无显著差异）。这些数据表明，缓释硝苯地平可降低颈总动脉和肱动脉的阻力。此外，这种药物似乎对大动脉的扩张性还有额外作用。
