Lewis Jane Ea, Williams Paul, Davies Jane H
Cardiff School of Health Sciences, Cardiff Metropolitan University, Cardiff, UK.
Department of Medical Physics, University Hospital of Wales, Cardiff, UK.
SAGE Open Med. 2016 Jul 12;4:2050312116659088. doi: 10.1177/2050312116659088. eCollection 2016.
This cross-sectional study aimed to individually and cumulatively compare sensitivity and specificity of the (1) ankle brachial index and (2) pulse volume waveform analysis recorded by the same automated device, with the presence or absence of peripheral arterial disease being verified by ultrasound duplex scan.
Patients (n=205) referred for lower limb arterial assessment underwent ankle brachial index measurement and pulse volume waveform recording using volume plethysmography, followed by ultrasound duplex scan. The presence of peripheral arterial disease was recorded if ankle brachial index <0.9; pulse volume waveform was graded as 2, 3 or 4; or if haemodynamically significant stenosis >50% was evident with ultrasound duplex scan. Outcome measure was agreement between the measured ankle brachial index and interpretation of pulse volume waveform for peripheral arterial disease diagnosis, using ultrasound duplex scan as the reference standard.
Sensitivity of ankle brachial index was 79%, specificity 91% and overall accuracy 88%. Pulse volume waveform sensitivity was 97%, specificity 81% and overall accuracy 85%. The combined sensitivity of ankle brachial index and pulse volume waveform was 100%, specificity 76% and overall accuracy 85%.
Combining these two diagnostic modalities within one device provided a highly accurate method of ruling out peripheral arterial disease, which could be utilised in primary care to safely reduce unnecessary secondary care referrals.
本横断面研究旨在分别及累积比较（1）踝臂指数和（2）由同一自动装置记录的脉搏容积波形分析的敏感性和特异性，并通过超声双功扫描验证是否存在外周动脉疾病。
因下肢动脉评估而转诊的患者（n = 205）接受了踝臂指数测量，并使用容积体积描记法记录了脉搏容积波形，随后进行了超声双功扫描。如果踝臂指数<0.9；脉搏容积波形分级为2、3或4；或者超声双功扫描显示血流动力学显著狭窄>50%，则记录存在外周动脉疾病。以超声双功扫描作为参考标准，结果测量指标为测量的踝臂指数与外周动脉疾病诊断中脉搏容积波形解释之间的一致性。
踝臂指数的敏感性为79%，特异性为91%，总体准确率为88%。脉搏容积波形的敏感性为97%，特异性为81%，总体准确率为85%。踝臂指数和脉搏容积波形的联合敏感性为100%，特异性为76%，总体准确率为85%。
在同一装置中结合这两种诊断方式提供了一种高度准确的排除外周动脉疾病的方法，可用于初级保健，以安全地减少不必要的二级保健转诊。
