TITLE：Vascular sound visualization system is useful for monitoring and surveillance of vascular access.

BACKGROUNDS: Vascular access (VA) is a lifeline for maintenance hemodialysis patients. Monitoring and surveillance of VA, therefore, play an important role for maintaining VA patency. Surveillance needs special apparatus to estimate the VA function, while, monitoring including physical examination does not usually need such devices but highly skill-dependent and qualitative.

PURPOSE: We report the clinical utility in monitoring and surveillance of VA using a newly developed electronic stethoscope and vascular sound visualization application.

METHODS: One hundred eight patients participated in the study. The vascular sounds were collected using the electronic stethoscope, converted into digital data, sent wirelessly to a personal computer, and then calculated. The units for the calculated intensity of the vascular sound were decibel [dB]. The intensity, however, was normalized as INDEX values ranging from 0 to 99 for practical use. Correlation between INDEX and the mean flow volume (mFV) and resistance index (RI) of brachial artery measured by Doppler ultrasound sonography were examined for VA surveillance. INDEX was continually measured at each dialysis session in ten patients who underwent the angioplasty for VA monitoring.

RESULTS: INDEX significantly correlated with the mFV (coefficient of correlation value = 0.68, p < 0.001) and RI (coefficient of correlation value = -0.51, p < 0.001) of brachial artery. Using the calculated cut-off values, the accuracy of INDEX for the diagnosis of AVF dysfunction ranged from 66% to 82%. INDEX attained the peak just after the angioplasty of culprit lesions and gradually decreased from one patient to another.

CONCLUSION: These results suggest that vascular sound visualization system can be useful in VA monitoring and surveillance for detecting and predicting the access stenosis.

SOUCE：Tsuboi M, Suzuki H, Kawai H, et al. Vascular sound visualization system is useful for monitoring and surveillance of vascular access[J]. J Vasc Access, 2021 :1129729821993984. DOI: 10.1177/1129729821993984.

背景：血管通路（VA）是维持性血液透析患者的生命线。因此，VA的监视和监视对于维持VA的通畅性起着重要的作用。监视需要专用设备来估计VA功能，而包括身体检查在内的监视通常不需要这种设备，而是高度依赖技术和定性的。

目的：我们报告了使用新开发的电子听诊器和血管声音可视化应用程序在VA监测中的临床实用性。

方法：108例患者参加了这项研究。使用电子听诊器收集血管声音，将其转换为数字数据，无线发送至个人计算机，然后进行计算。计算出的血管声音强度的单位为分贝[dB]。但是，实际使用时，将强度标准化为INDEX值，范围从0到99。通过多普勒超声检查，检查INDEX与肱动脉平均流量（mFV）和阻力指数（RI）之间的相关性，以进行VA监测。在每次透析过程中，对接受血管成形术监测VA的10例患者进行INDEX连续测量。

结果：INDEX与肱动脉的mFV（相关系数= 0.68，p <0.001）和RI（相关系数-0.51，p <0.001）显着相关。使用计算出的临界值，INDEX诊断AVF功能障碍的准确性为66％至82％。受累病变血管成形术后不久，INDEX达到峰值，然后从一名患者逐渐下降到另一名患者。

结论：这些结果表明，血管声音可视化系统可用于VA监测中，以检测和预测通道狭窄。

启发：VA监测是一种重要探索，早期发现病变，有助于下一步方案的制定。