基于外周动脉获取的主动脉压力与血流波形测量aoPWV的方法研究

Aortic pulse wave velocity (aoPWV), the "gold standard" for measurement of aortic stiffness, is widely used for the early prevention and cure of cardiovascular diseases. A simple and accurate method for the measurement of aoPWV has been an important issue. In previous study, we have proposed a method to obtain aoPWV from a single radial pressure waveform, which is effective in young and middle-aged healthy humans. In the present study, we propote a novel method for determining aoPWV based on measurements of peripheral pulse waves, which is convenient and widely-applicable over a large range of age. In order to address this comprehensively, we will conduct the following works. First, we propose an algorithm for deriving finger artery blood flow from photoplethysmographical. Rules of blood flow in arterial system are studied and a transfer function is set up based on mathematical methods, which is then used to construct aortic flow waveform. The aortic pressure waveform is generated from the radial pressure pulse using a generalized transfer function. Aortic pressure waveform is fused with aortic blood flow by impedance analysis, and then decomposed into forward and backward waves. This method can solved the problem that the accuracy of aortic pulse transit time is not enough, which is generally present in single-point measurement. Second, the movement of the first effective reflected site with aging is investigated to build transmission distance model of backward wave, which lay foundation for promoting a widely-applicable measurement of aoPWV. Third, a follow-up study on the effect of heart rate on the measurement of aoPWV is also made to build the correction model. The completion of this project will provide a new way for detecting premature arterial stiffness, and have important application prospect in the field of prevention and cure of cardiovascular diseases.

主动脉脉搏波速度(aoPWV)作为动脉硬化检测的"金标准"，广泛应用于心血管病的"上游防治"。如何进行简单准确的aoPWV测量是非常重要的研究课题。前期工作中，我们实现了基于桡动脉脉搏波的面向中青年的aoPWV快速检测。本项目将发展一种基于桡动脉和指端容积脉搏波的aoPWV测量方法：首先提出指端容积脉搏波中指动脉血流波形的分离算法，通过对血流传递规律的研究，建立主动脉血流波形的构造方法；采用传递函数基于桡动脉脉搏波重构主动脉压力波形，提出基于压力与血流波形融合的脉搏波传递时间(aoPTT)测量方法，解决单点法普遍存在的aoPTT测量精度不足问题；研究面向中老年的反射点随年龄的移动规律，构建反射波传递距离模型，实现aoPWV测量方法的年龄普适性；探索心率变化对aoPWV的影响机制并建立校正模型，提高测量信度。本项目的研究成果将为动脉硬化早期检测提供新途径，在心血管病防治领域具有重要应用价值。

主动脉脉搏波速度(aoPWV)作为动脉硬化检测的"金标准"，广泛应用于心血管病的"上游防治"。如何进行简单准确的aoPWV测量是非常重要的研究课题。前期工作中，我们实现了基于桡动脉脉搏波的面向中青年的aoPWV快速检测。本项目主要研究内容包括（1）基于外周动脉重构主动脉的传递函数研究。本研究采用交叉验证技术确定模型阶次上限，同时为了降低运算难度和达到理想效果，确定了最终阶次。我们采用时延估计函数确定了模型的最终时延。（2）基于压力与血流信息融合的aoPTT测量方法研究。采用传递函数和分离算法从桡动脉脉搏波和指端光电容积脉搏波中获取主动脉压力波形和主动脉血流波形，通过阻抗分析技术实现了aoPTT的准确测量。（3）反射点移动和心率变异影响规律研究。研究心率对aoPTT的影响机制，建立了校正方法；研究反射点随年龄的移动规律，构建了反射波的传递距离模型，建立了具有年龄普适性的aoPWV测量技术。（4）原型检测系统研制及性能验证研究。我们开发了原型检测系统及双路脉搏波信号分析软件，研究结果表明，系统与Complior测量结果显著高度相关（r =0.79, P <0.01），且具有良好的短期重复性（ICC=0.86）。该系统能够满足动脉硬化的早期筛查需求，在大众健康领域具有广泛的应用前景。相关研究成果已在国内外有影响力的期刊发表，共发表SCI论文3篇；发表EI会议论文1篇；发表中文核心期刊论文1篇，录用待发表的中文核心期刊论文2篇；申请国家发明专利4项，其中1项授权；培养研究生6名。