Stergiopulos N, Segers P, Westerhof N
Biomedical Engineering Laboratory, Swiss Federal Institute of Technology, Parc Scientifique d'Ecublens, 1015 Lausanne, Switzerland.
Am J Physiol. 1999 Feb;276(2):H424-8. doi: 10.1152/ajpheart.1999.276.2.H424.
We determined total arterial compliance from pressure and flow in the ascending aorta of seven anesthetized dogs using the pulse pressure method (PPM) and the decay time method (DTM). Compliance was determined under control and during occlusion of the aorta at four different locations (iliac, renal, diaphragm, and proximal descending thoracic aorta). Compliance of PPM gave consistently lower values (0.893 +/- 0.015) compared with the compliance of DTM (means +/- SE; r = 0.989). The lower compliance estimates by the PPM can be attributed to the difference in mean pressures at which compliance is determined (mean pressure, 81.0 +/- 3.6 mmHg; mean diastolic pressure, over which the DTM applies, 67.0 +/- 3.6 mmHg). Total arterial compliance under control conditions was 0.169 +/- 0. 007 ml/mmHg. Compliance of the proximal aorta, obtained during occlusion of the proximal descending aorta, was 0.100 +/- 0.007 ml/mmHg. Mean aortic pressure was 80.4 +/- 3.6 mmHg during control and 102 +/- 7.7 mmHg during proximal descending aortic occlusion. From these results and assuming that upper limbs and the head contribute as little as the lower limbs, we conclude that 60% of total arterial compliance resides in the proximal aorta. When we take into account the inverse relationship between pressure and compliance, the contribution of the proximal aorta to the total arterial compliance is even more significant.
我们使用脉压法（PPM）和衰减时间法（DTM），根据七只麻醉犬升主动脉的压力和流量来测定总动脉顺应性。顺应性在对照条件下以及在主动脉四个不同位置（髂动脉、肾动脉、膈肌和胸降主动脉近端）闭塞期间进行测定。与DTM的顺应性（均值±标准误；r = 0.989）相比，PPM的顺应性始终给出较低的值（0.893±0.015）。PPM较低的顺应性估计值可归因于测定顺应性时的平均压力差异（平均压力，81.0±3.6 mmHg；DTM适用的平均舒张压，67.0±3.6 mmHg）。对照条件下的总动脉顺应性为0.169±0.007 ml/mmHg。在胸降主动脉近端闭塞期间获得的近端主动脉顺应性为0.100±0.007 ml/mmHg。对照期间平均主动脉压力为80.4±3.6 mmHg，胸降主动脉近端闭塞期间为102±7.7 mmHg。根据这些结果，并假设上肢和头部对总动脉顺应性的贡献与下肢一样小，我们得出结论，总动脉顺应性的60%存在于近端主动脉中。当我们考虑压力与顺应性之间的反比关系时，近端主动脉对总动脉顺应性的贡献更为显著。
