Reproducibility and concordance of Pedal Acceleration Time between students, residents and experts operators: Single-center prospective study

Critical limb threatening ischemia (CLTI) is defined as peripheral artery disease (PAD) with rest pain, nonhealing wounds, or tissue loss. At this stage, this is a severe pathology with a high rate of ischemic events in the lower limbs and cardiovascular events. The ankle brachial pressure index (ABI) is the first line diagnostic method, but can be falsely high because of stiffened ankle arteries related to medial artery calcifications. The Pedal Acceleration Time (PAT) has been described as valid even in cases of diabetes or chronic renal failure. In order to evaluate this measurement in untrained operators, we carried out a prospective study comparing measurement performance between medical students, residents and senior doctors. We performed a prospective monocentric study. All patients were included from the departments of Vascular Medicine and Surgery of the CHU Amiens-Picardie from February 2024 to June 2024. The main objective of the study was to measure the inter-observer agreement of PAT in patients with PAD. Twenty-five patients were consecutively included in this study. ABI was successfully performed in 19 (76%) with a mean of 0.72 (±0.2). PAT was performed in 24 patients (96%) with a mean of 126ms (±40). All inter-observer comparison tests showed good agreement. The concordance between senior doctors and residents was 0.900 [0.768-0.957]. The concordance between senior doctors and students was 0.962 [0.923-0.984]. We show that PAT which is a recently described measurement can be performed not only by doctors with experience using Doppler ultrasound, but also by operators with minimal training.