Duplex ultrasound derived maximal systolic acceleration can be a reliable and rapid alternative to ankle brachial pressure indices for the diabetic population with lower extremity arterial disease; a prospective, observational cohort study

Abstract

Objectives: Ankle brachial pressure index (ABPI) is limited for diabetic patients. This can have costly impacts upon patient's quality of life along with healthcare budgets, with diabetic care equating to approximately 10% of NHS expenditure.11 We aimed to determine whether ultrasound waveform parameters are an alternative for quantifying lower extremity peripheral arterial disease (PAD) where ABPI is unreliable. Design: This was a prospective, observational study. Waveform parameters, systolic rise time (SRT), maximal systolic acceleration (AccMax) and peak systolic velocity (PSV) were recorded at ankle and compared to the ABPI and an aorta-ankle duplex ultrasound scan (DUS) as gold standard. Setting: Measurements were obtained by a Clinical Vascular Scientist at the Royal Free Hospital. Participants: Participants (≥18yrs) with known PAD, but without previous vascular intervention were allocated to non-diabetic control ( n = 24) and diabetic test groups ( n = 22). Outcome measures: The primary outcome measure was the correlation of novel ultrasound derived indices to PAD severity. The secondary outcome was the efficacy of this correlation in the diabetic population. Results: AccMax was most powerful in detecting PAD in both groups when compared to ABPI in the controls ( r = 0.805; p < 0.01) and to DUS in control and test groups ( r = −0.633 to −0.643; p < 0.01). In the test group, PSV did not consistently quantify PAD. SRT measurements were inconclusive throughout. Conclusion: AccMax is a rapid alternative tool for diagnosing PAD in diabetic patients. With further research, this simple test may prove useful for monitoring PAD progression in patients unsuitable for ABPI, reducing the need for lengthy repeat duplex scans.