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.

Effectiveness of bedside investigations to diagnose peripheral artery disease among people with diabetes mellitus: A systematic review

“…Thirty‐five studies 34‐37,39‐50,52‐62,64,65,67‐72 involving 3905 participants and 3 studies 33,38,51 including 497 limbs (number of participants not reported) investigated the ability of the ABI to identify PAD. Seven studies involving 1372 people 34,39,44,57,58,65,69 and 1 study of 89 limbs (number of participants not reported) 33 investigated the diagnostic accuracy of the TBI.…”

“…For the 38 studies using the ABI as an index test, the threshold used to indicate a positive (i.e., abnormal) test varied. Nine studies used a threshold of <0.9, 38,42,54,56,59,60,70–72 8 studies used a threshold of ≤0.9, 34,39,41,43,52,53,58,64,65 7 studies use a threshold of <0.9 and >1.3, 33,46,50,55,57,61,69 2 studies used a threshold of ≤0.9 and ≥1.3, 37,40 3 studies used a threshold of <0.9 and >1.4 51,62,65 one used ≤0.9 and ≥1.4 48 and the remainder did not state a threshold. Two studies compared the diagnostic accuracy of ABI ≤0.9 and ABI ≤0.90 or >1.3/1.4 34,43 .…”

“…The majority of included studies used CDUS as a reference standard ( n = 31) with diagnostic threshold variables but most commonly presence of one or more stenoses of ≥50% 33,34,37–39,41–44,46–48,52–57,59,60,62–72 . Five studies used DSA 36,40,45,50,58 2 studies used CTA 49,61 and 1 study used CTA or MRA 35 .…”

“…increases the pre-test probability by a moderate to large amount, that is, the person is likely to have PAD [33][34][35]37,38,[40][41][42][43]46,48,50,51,53,54,56,59,60,62,64,65,67,69,70 and therefore may be a useful test for diagnosing PAD. In contrast, for populations with DFU, the same ABI threshold (<0.9) appears to increase the pre-test probability of disease by a relatively small amount.…”

“…Of the 40 studies relating to diagnostic accuracy undertaken in populations with diabetes, 28 of the studies used prospective recruitment 33,[36][37][38][39][41][42][43][44]46,47,[52][53][54][55][56][57][58][59][60]62,65,[67][68][69][70][71][72] and the remainder used retrospective recruitment. 34,35,40,45,[48][49][50][51]61,63,64,66 Eight studies reported including participants with active DFU, 39,43,44,48,57,58,69,72 with the proportion of the study population affected ranging from 6.6% to 100%.…”