Pedal acceleration time (PAT) is a novel non-invasive perfusion measurement that may be useful in the management of patients with ulceration and gangrene. The objective of this study was to report the association between PAT and wound healing, amputation free survival (AFS), and mortality at one year. This prospective observational study reviewed all patients who underwent PAT after presentation with ulceration or gangrene from 1 January 2020 to 30 June 2022. PAT was defined as the time (in milliseconds) from the onset of systole to the peak of systole in the mid artery. The final PAT of a limb was used to assess outcomes (presenting PAT if no revascularisation, or post-revascularisation PAT). Wound healing, major limb amputation, and death at one year were collected. Healing was assessed with Fine-Gray competing risks model, AFS via logistic regression, and survival using Cox proportional hazards model. Overall, 265 patients (307 limbs) were included. The median patient age was 71 years and 74.0% (196/265) had diabetes mellitus. Patient demographics were similar among the final PAT category cohorts. Compared with a final PAT category 1, analysis of one year outcomes showed that the final PAT categories 2- 4 had lower wound healing (category 2, hazard ratio [HR] 0.62, 95% confidence interval [CI] 0.43 - 0.9, p= .012; category 3, HR 0.21, 95% CI 0.08 - 0.58, p= .002; category 4, HR 0.12, 95% CI 0.04 - 0.34, p < .001), lower AFS (category 2, odds ratio [OR] 2.86, 95% CI 1.64 - 5.0, p < .001; category 3, OR 5.1, 95% CI 1.71 - 15.22, p= .003; category 4, OR 12.59, 95% CI 4.34 - 36.56, p < .001), and lower survival (category 2, HR 1.89, 95% CI 1.17 - 3.03, p=.009; category 3, HR2.37, 95% CI 1.05 - 5.36, p= .039; category 4, HR 4.52, 95% CI 2.48 - 8.21, p < .001). The final PAT measurement is associated with wound healing, AFS, and death at one year. PAT may be a valuable tool to assess perfusion of the foot.
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