Lowe A, Harrison W, El-Aklouk E, Ruygrok P, Al-Jumaily A M
Pulsecor Limited, Auckland, New Zealand.
J Biomech. 2009 Sep 18;42(13):2111-5. doi: 10.1016/j.jbiomech.2009.05.029. Epub 2009 Aug 7.
Elevated central arterial (aortic) blood pressure is related to increased risk of cardiovascular disease. Methods of non-invasively estimating this pressure would therefore be helpful in clinical practice. To achieve this goal, a physics-based model is derived to correlate the arterial pressure under a suprasystolic upper-arm cuff to the aortic pressure. The model assumptions are particularly applicable to the measurement method and result in a time-domain relation with two parameters, namely, the wave propagation transit time and the reflection coefficient at the cuff. Central pressures estimated by the model were derived from completely automatic, non-invasive measurement of brachial blood pressure and suprasystolic waveform and were compared to simultaneous invasive catheter measurements in 16 subjects. Systolic blood pressure agreement, mean (standard deviation) of difference was -1 (7)mmHg. Diastolic blood pressure agreement was 4 (4)mmHg. Correlation between estimated and actual central waveforms was greater than 90%. Individualization of model parameters did not significantly improve systolic and diastolic pressure agreement, but increased waveform correlation. Further research is necessary to confirm that more accurate brachial pressure measurement improves central pressure estimation.
中心动脉（主动脉）血压升高与心血管疾病风险增加相关。因此，非侵入性估计该血压的方法在临床实践中会有所帮助。为实现这一目标，推导了一个基于物理学的模型，以关联超收缩期上臂袖带压力下的动脉压与主动脉压。该模型假设特别适用于测量方法，并产生一个具有两个参数的时域关系，即波传播渡越时间和袖带处的反射系数。通过该模型估计的中心压力来自肱动脉血压和超收缩期波形的完全自动、非侵入性测量，并与16名受试者同时进行的有创导管测量结果进行比较。收缩压一致性方面，差值的均值（标准差）为-1（7）mmHg。舒张压一致性为4（4）mmHg。估计的中心波形与实际中心波形之间的相关性大于90%。模型参数的个体化并未显著改善收缩压和舒张压的一致性，但增加了波形相关性。需要进一步研究以确认更准确的肱动脉压力测量是否能改善中心压力估计。
