Abstract Body: Introduction: Along with ankle brachial index, lower extremity arterial doppler(LEAD) is a commonly used non-invasive test for peripheral arterial disease. Traditional analysis relied on grading the waveforms as – triphasic, biphasic, monophasic or absent, with triphasic considered normal, monophasic and absent abnormal, while biphasic waveforms were defined variably and often considered abnormal. A 2020 Society of Vascular Medicine position statement recommended abandoning the term biphasic and using the terms multiphasic and monophasic, but this modern classification has not been widely adopted and not been compared to the traditional classification.
Methods: Consecutive patients who underwent LEAD and peripheral angiography were included in this retrospective study. Arterial stenosis >75% by angiography was considered obstructive PAD.
Results: 1054 arterial segments in 106 patients(63 women) were included. Using traditional classification, triphasic waveforms occurred in 23.7%, biphasic 52%, monophasic 21.9% and 2.4% had absent wave forms. A biphasic wave form was associated with obstructive PAD in only 21% of cases, and a monophasic wave form in 53.6% . Sensitivity and specificity of the traditional classification(biphasic considered abnormal) was 93.1% and 29.7%(accuracy 46.3%, AUC 0.614) while that of the newer classification was 51.4% and 85.3%(accuracy 76.4%, AUC 0.684) respectively( pair wise comparison of ROC curves, p = 0.0001).
Conclusion: In addition to reducing variability in reporting, the newer proposed Doppler wave form(multiphasic vs monophasic) was more accurate in classifying obstructive PAD than the traditional classification. LEAD should interpreted in conjunction with clinical symptoms and ABI and abnormal waveforms should not reflexly lead to invasive and costly investigations.