Arathy R, Nabeel P M, Joseph Jayaraj, Sivaprakasam Mohanasankar
Annu Int Conf IEEE Eng Med Biol Soc. 2018 Jul;2018:4571-4574. doi: 10.1109/EMBC.2018.8513156.
In this work, we demonstrate an accelerometric patch probe with two microelectromechanical accelerometer sensors for local pulse wave velocity (PWV) measurement from the carotid artery. Dual acceleration plethysmogram (APG) signals were acquired from a small section of the artery by keeping the sensors at 32 mm apart. A custom analog front-end circuit (inter-channel delay $< 0.15$ ms) was used for reliable signal acquisition. Simultaneously acquired dual APG signals were processed in real-time and local PWV was evaluated in a beat-by-beat manner. A transversal study on a cohort of 15 volunteers (4 males, 11 females, mean age = $25.6 \pm 1.92$ years) was conducted to validate the developed prototype system. During the study, carotid local PWV and brachial blood pressure (BP) parameters were recorded from both sitting and standing posture. The absolute values of measured carotid local PWV were in the range of 3 m/s - 4.2 m/s (beat-to-beat variation $=$ 2.61% - 13.07%). Measured local PWV values significantly correlated with brachial systolic BP ($\textbf{R}^{\mathbf {2}} =$ 0.87) and diastolic BP ($\textbf{R}_{\mathbf {, }}^{\mathbf {2}} \quad =$ 0.79). Logarithmic functions provided the best monotonic model for carotid local PWV versus brachial BP parameters for the recorded data points. The developed population-specific mathematical models were then used for cuffless evaluation of BP parameters from carotid local PWV. The root-mean-square error in the estimated systolic and diastolic pressure was 7.53 mmHg and 6.0 mmHg respectively. Study results illustrate the potential application of the developed dual-accelerometric system in non-invasive, continuous cuffless BP measurement techniques.
在这项工作中，我们展示了一种带有两个微机电加速度计传感器的加速度测量贴片探头，用于测量颈动脉的局部脉搏波速度（PWV）。通过将传感器保持32毫米的间距，从一小段动脉采集双加速度体积描记图（APG）信号。使用定制的模拟前端电路（通道间延迟<0.15毫秒）进行可靠的信号采集。对同时采集的双APG信号进行实时处理，并逐搏评估局部PWV。对15名志愿者（4名男性，11名女性，平均年龄=25.6±1.92岁）进行了横向研究，以验证所开发的原型系统。在研究过程中，记录了坐姿和站姿下的颈动脉局部PWV和肱动脉血压（BP）参数。测得的颈动脉局部PWV绝对值在3米/秒至4.2米/秒范围内（逐搏变化=2.61%-13.07%）。测得的局部PWV值与肱动脉收缩压（R²=0.87）和舒张压（R²=0.79）显著相关。对数函数为记录的数据点提供了颈动脉局部PWV与肱动脉血压参数之间最佳的单调模型。然后，使用所开发的特定人群数学模型从颈动脉局部PWV进行无袖带血压参数评估。估计的收缩压和舒张压的均方根误差分别为7.53毫米汞柱和6.0毫米汞柱。研究结果说明了所开发的双加速度测量系统在无创、连续无袖带血压测量技术中的潜在应用。
