Gizdulich P, Imholz B P, van den Meiracker A H, Parati G, Wesseling K H
Clinical Physiopathology Department, University of Florence, Italy.
J Hypertens. 1996 Feb;14(2):243-50. doi: 10.1097/00004872-199602000-00014.
Arterial pressure waveforms distort between brachial and finger arteries, causing differences mainly in systolic pressure. Distortion, reportedly, can be removed by applying a waveform filter to the finger pressure.
We analysed the data from two studies that detected discrepancies in systolic tracking between Finapres and brachial pressures. The first set comprised waveforms of seven volunteers during incremental bicycle exercise to exhaustion and the second set comprised waveforms of eight volunteers during increasing phenylephrine infusion.
We applied the filter and compared 1 min averaged unfiltered and waveform-filtered finger and brachial pressures.
During exercise, finger systolic pressure overestimated brachial increasingly, from 7(SD 10) mmHg at rest to 27(17) mmHg at maximal exertion. Differences were reduced by waveform filtering from 3 (SD 9)mmHg at rest to 1 (SD 15)mmHg at maximal exertion. During phenylephrine infusion finger systolic pressure overestimated brachial pressure, but the magnitude of the overestimate decreased from 14 (SD 15)mmHg at baseline to -1(SD 16)mmHg at maximal rate. After waveform filtering overestimation was an almost constant 6(SD 11)mmHg. Median baroreflex sensitivities from brachial, unfiltered and waveform-filtered finger pressure were 5.8, 7.5 and 5.3 ms/mmHg and correlation increased after filtering. The results indicate improved systolic pressure tracking after waveform filtering.
Finger pressure distortion follows a general pattern correctable by waveform filtering. Waveform filtering allows a 'brachial' view to be obtained from Finapres data.
肱动脉与指动脉之间的动脉压力波形会发生畸变，主要导致收缩压出现差异。据报道，通过对指压应用波形滤波器可消除这种畸变。
我们分析了两项研究的数据，这两项研究检测到Finapres血压与肱动脉血压在收缩压追踪方面存在差异。第一组数据包括7名志愿者在递增式自行车运动至力竭过程中的波形，第二组数据包括8名志愿者在去氧肾上腺素输注量增加过程中的波形。
我们应用该滤波器，并比较了未经过滤和经过波形滤波的1分钟平均指压与肱动脉压。
运动期间，指收缩压对肱动脉收缩压的高估程度逐渐增加，从静息时的7（标准差10）mmHg增至最大运动时的27（17）mmHg。通过波形滤波，差异从静息时的3（标准差9）mmHg降至最大运动时的1（标准差15）mmHg。在去氧肾上腺素输注期间，指收缩压高估了肱动脉压，但高估幅度从基线时的14（标准差15）mmHg降至最大输注速率时的-1（标准差16）mmHg。经过波形滤波后，高估几乎恒定在6（标准差11）mmHg。肱动脉、未经过滤和经过波形滤波的指压的压力反射敏感性中位数分别为5.8、7.5和5.3 ms/mmHg，滤波后相关性增加。结果表明波形滤波后收缩压追踪得到改善。
指压畸变遵循一种可通过波形滤波校正 的一般模式。波形滤波可从Finapres数据中获得“肱动脉”视角。
