Department of Aerospace & Mechanical Engineering, University of Southern California, Los Angeles, United States of America.
Division of Cardiovascular Medicine, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, United States of America.
Physiol Meas. 2021 Nov 2;42(10). doi: 10.1088/1361-6579/ac2671.
Wave intensity (WI) analysis is a well-established method for quantifying the energy carried in arterial waves, providing valuable clinical information about cardiovascular function. The primary drawback of this method is the need for concurrent measurements of both pressure and flow waveforms.. We have for the first time investigated the accuracy of a novel methodology for estimating wave intensity employing only single pressure waveform measurements; we studied both carotid- and radial-based estimations in a large heterogeneous cohort.Tonometry was performed alongside Doppler ultrasound to acquire measurements of both carotid and radial pressure waveforms as well as aortic flow waveforms in 2640 healthy and diseased participants (1439 female) in the Framingham Heart Study. Patterns consisting of two forward waves (Wf1, Wf2) and one backward wave (Wb1) along with reflection metrics were compared with those obtained from exact WI analysis.. Carotid-based estimates correlated well for forward peak amplitudes (Wf1,r = 0.85,p < 0.05; Wf2,r = 0.72,p < 0.05) and peak time (Wf1,r = 0.94,p < 0.05; Wf2,r = 0.98,p < 0.05), and radial-based estimates correlated fairly to poorly for amplitudes (Wf1,r = 0.62,p < 0.05; Wf2,r = 0.42,p < 0.05) and peak time (Wf1,r = 0.04,p = 0.10; Wf2,r = 0.75,p < 0.05). In all cases, estimated Wb1 measures were not correlated. Reflection metrics were well correlated for healthy patients (r = 0.67,p < 0.05), moderately correlated for valvular disease (r = 0.59,p < 0.05) and fairly correlated for CVD (r = 0.46,p < 0.05) and heart failure (r = 0.49,p < 0.05).. These findings indicate that pressure-only WI produces accurate results only when forward contributions are of primary interest and only for carotid pressure waveforms. The pressure-only WI estimations of this work provide an important opportunity to further the goal of uncovering clinical insights through wave analysis affordably and non-invasively.
波强（WI）分析是一种用于量化动脉波所携带能量的成熟方法，可为心血管功能提供有价值的临床信息。该方法的主要缺点是需要同时测量压力和流量波形。我们首次研究了一种仅使用单个压力波形测量来估计波强的新方法的准确性；我们在一个大型异质队列中研究了基于颈动脉和桡动脉的估计。在弗雷明汉心脏研究中，对 2640 名健康和患病参与者（1439 名女性）进行了血压和多普勒超声检查，以获取颈动脉和桡动脉压力波形以及主动脉流量波形的测量值。将由两个前向波（Wf1、Wf2）和一个后向波（Wb1）组成的模式以及反射指标与从精确 WI 分析获得的模式进行了比较。基于颈动脉的估计与前向峰值幅度（Wf1，r=0.85，p<0.05；Wf2，r=0.72，p<0.05）和峰值时间（Wf1，r=0.94，p<0.05；Wf2，r=0.98，p<0.05）具有良好的相关性，而基于桡动脉的估计与幅度（Wf1，r=0.62，p<0.05；Wf2，r=0.42，p<0.05）和峰值时间（Wf1，r=0.04，p=0.10；Wf2，r=0.75，p<0.05）相关性差。在所有情况下，估计的 Wb1 测量值均无相关性。对于健康患者，反射指标相关性良好（r=0.67，p<0.05），对于瓣膜疾病中度相关（r=0.59，p<0.05），对于 CVD（r=0.46，p<0.05）和心力衰竭（r=0.49，p<0.05）相关性较好。这些发现表明，仅压力 WI 仅在主要关注前向贡献时才能产生准确的结果，并且仅适用于颈动脉压力波形。这项工作的仅压力 WI 估计为通过负担得起且非侵入性的波分析揭示临床见解提供了一个重要机会。
