基于袖带振荡波的个体化无创伤中心动脉压动态监测技术研究

Central aortic pressure (CAP) is a more direct reflection of left ventricular afterload and coronary perfusion than brachial blood pressure. Central aortic pressure is a better predictor of target organ damage and major cardiovascular outcomes. Existing noninvasive central aortic pressure measurement methods apply the general transfer function (GTF) to reconstruct the central pressure using the periphery arterial pressure wave. These methods applying tonometry method on the radial artery to reconstruct the CAP failed to reflect the differences between individuals. The tonometry method relyed on skilled operator requirements and this prevent the method's application out-of-office. The present research intends to propose an individualized cuff-based central aortic pressure reconstructing method which involves two steps. In previous researches, our team has found the phenomena of Korotkoff sound delay time (KDT). The forefront of the brachial artery pulse wave can be obtained by the whole process of KDT using cuff method of blood pressure measurement. These waves was used as a priori knowledge in the semi-blind source separation to reconstruct the brachial artery pressure wave; Korotkoff sound delay time and pulse wave transmission time (PTT) are high correlation and the KDT is used to substitute PTT as to get a personalized transfer function between the brachial artery - the central aortic pressure. The present method is individual adaptive. The central aortic pressure and its waveform can be measured only by a conventional cuff which is convenient for the operation and easy to implement. The present research may help the reconstruction of central aortic pressure be able to achieve out-of-office and which makes the 24-hour ambulatory monitoring of central arterial pressure feasible.

中心动脉压较肱动脉血压直接反映左心室后负荷及冠状动脉灌注，能更好的预测靶器官损害及主要心血管事件的发生。现有的无创中心动脉压测量方法大多采用"通用传递函数"转换，未能反映个体间的差异；基于桡动脉张力法的技术对操作者要求高、限制了其在诊室外推广应用。针对此不足，本项目拟研究一种基于袖带振荡波的个性化的无创中心动脉压力波重建方法，分两步完成重建。其中利用了课题组前期研究中发现的柯氏音延时（KDT)现象及其规律，根据袖带法血压测量全过程的KDT计算肱动脉脉搏波上升前沿，并将其作为先验知识用于半盲源分离以获得肱动脉压力波；利用柯氏音延迟时间和脉搏波传递时间(PTT)之间的高度相关性，用KDT代替PTT用于获得个性化的"肱动脉-中心动脉"压力波传递函数。该方法具有个体自适应特征，可以通过常规袖带测量中心动脉压及其波形，操作难度低，易于实现，将能够实现中心动脉压的诊室外自测和24小时动态监测。

中心动脉压较肱动脉血压直接反映左心室后负荷及冠状动脉灌注，能更好的预测靶器官损害及主要心血管事件的发生。现有的无创中心动脉压测量方法大多采用“通用传递函数”转换，未能反映个体间的差异；基于桡动脉张力法的技术对操作者要求高、限制了其在诊室外推广应用。针对此不足，本项目研究了一种基于袖带振荡波的个性化的无创中心动脉压力波重建方法。本研究利用了课题组前期研究中发现的柯氏音延时（KDT)现象及其规律。首先，根据袖带法血压测量全过程的KDT 测算肱动脉脉搏波上升前沿，并将其作为先验知识用于获得肱动脉压力波，同时结合袖带压力高于收缩压及袖带压低于舒张压力时的袖带振荡波形以综合比较最终获得袖带下肱动脉内的动脉压力波形。其次，利用柯氏音延迟时间和脉搏波传递时间(PTT)之间的高度相关性，用KDT 代替PTT 用于获得个性化的“肱动脉-中心动脉”压力波传递函数。根据上述方案设计了试验平台，根据血压袖带内的振荡波和柯氏音信号估测中心动脉压波形和大小，并用同步监测的人体有创中心动脉压进行对比试验，验证了该方案的可行性。该方法具有个体自适应特征，可以通过常规袖带测量中心动脉压及其波形，操作难度低，易于实现，将能够实现中心动脉压的诊室外自测和24小时动态监测。