Test-retest Reliability and Minimal Detectable Change in Exercise Oximetry in Claudicants.

BACKGROUND: Exercise transcutaneous oxygen pressure measurement (Exercise-TcPO2) can be used to diagnose Lower Extremity Artery Disease (LEAD) and allows the quantification of limb ischemia during exercise on treadmill. Exercise-TcPO2 test-retest reliability in patients with LEAD and severe walking impairment is unknown. The aim of this study was to evaluate the test-retest reliability, standard error of measurement (SEM), and Minimal Detectable Change (MDC) of exercise-TcPO2 in patients with claudication. METHODS: Data were collected from patients that performed 2 treadmill tests within a 1-month interval. Delta from Rest of Oxygen Pressure (DROP) values were measured at both buttocks (proximal) and both calves (distal). Test-retest reproducibility was assessed by recording transcutaneous oximetry measurements twice and expressed as SEM and intra-class correlation coefficients. MDC was calculated using the formula MDC = SEM x 1.96 x √ 2. RESULTS: Twenty eight LEAD patients (61 ± 9 years old) were included. Intra-class correlation coefficients were 0.66 [0.50, 0.79] and 0.65 [0.49, 0.79] for the proximal and distal levels, respectively. The SEM of DROP at the proximal and distal levels were 7 [6, 9] mm Hg and 9 [8, 11] mm Hg, respectively. The SEM for all (proximal and distal) DROP values was 8 [7, 10] mm Hg and the MDC of DROP was 23 mm Hg. CONCLUSIONS: Exercise-TcPO2 with measurement of DROP values has a moderate test-retest reliability in LEAD patients with a maximal walking distance ≤ 300m. For an individual, an improvement or deterioration in DROP of ≥ 23 mm Hg after an intervention would be required to be 95% confident that the change is significant. It should be considered in evaluating the impact of treatment in patients with claudication.

Performance of finger systolic blood pressure measurement to detect digital occlusive arterial disease in systemic sclerosis.

OBJECTIVE: Digital ulcers related to digital occlusive arterial disease (DOAD) are frequent in patients with SSc. Finger systolic blood pressure (FSBP) and digital-brachial pressure index (DBI) using laser Doppler flowmetry constitute a non-invasive means of detecting DOAD in SSc, although thresholds have yet to be established for defining DOAD. The purpose of this study was to ascertain FSBP and DBI thresholds to detect DOAD in SSc patients. The intra/interday reproducibility of curve reading by four vascular physicians in relation to finger pressure measurement was also investigated. METHODS: SSc patients were followed in this single-centre study (Rennes University Hospital, France) between November 2017 and October 2019.These patients underwent tests before and after heating at two visits spaced 10 days apart. DOAD was diagnosed on the basis of post-warming skin blood flow of ≤206 arbitrary units measured by laser Doppler flowmetry, contingent on previous results validated by arteriography as a gold standard. An interday kappa coefficient with a 95% confidence interval was used to assess reproducibility. RESULTS: Sixteen [10 females; mean age: 63 (9) years] SSc patients were included. Mean time interval between visits was 9 (5) days. The best FSBP threshold for DOAD diagnosis was 76 mmHg and DBI was 0.74 after warming. FSBP and DBI sensitivity/specificity were 59.1% (95% CI: 49.6, 68.5%)/92.5% (95% CI: 85.3, 99.6%) and 73.3% (95% CI: 64.9, 81.8%)/83.0% (95% CI: 72.9, 93.1%), respectively. Intra/interday reproducibility ranged from fair to good. CONCLUSION: The conclusions drawn from this study suggest that FSBP ≤ 76 mmHg and DBI ≤ 0.74 thresholds are potentially reliable indicators of DOAD and demonstrate fair to good intra- and interday reproducibility. TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT03264820.

A systematic review of lower extremity electrical stimulation for treatment of walking impairment in peripheral artery disease.

Lower extremity peripheral artery disease (PAD) induces an ischemic pain in the lower limbs and leads to walking impairment. Electrical stimulation has been used in patients with PAD, but no systematic review has been proposed to address the efficacy of the technique as a treatment for walking impairment in PAD. A systematic search was performed to identify trials focused on electrical stimulation for the treatment of walking impairment in patients with PAD in the Cochrane Central Register, PubMed, Embase, and the Web of Science. Studies were included where the primary outcomes were pain-free walking distance and/or maximal walking distance. When appropriate, eligible studies were independently assessed for quality using the Cochrane Collaboration's tool for assessing risk of bias. Five studies eligible for inclusion were identified, of which only two were randomized controlled studies. Trial heterogeneity prevented the use of the GRADE system and the implementation of a meta-analysis. Three types of electrical stimulation have been used: neuromuscular electrical stimulation (NMES, n = 3), transcutaneous electrical stimulation (n = 1), and functional electrical stimulation (n = 1). The two available randomized controlled studies reported a significant improvement in maximal walking distance (+40 m/+34% and +39 m/+35%, respectively) following a program of NMES. Owing to the low number of eligible studies, small sample size, and the risk of bias, no clear clinical indication can be drawn regarding the efficacy of electrical stimulation for the management of impaired walking function in patients with PAD. Future high-quality studies are required to define objectively the effect of electrical stimulation on walking capacity.

Impact of an Educational Intervention on Ankle-Brachial Index Performance Among Medical Students and Fidelity Assessment at Six Months.

BACKGROUND: The resting ankle-brachial index (ABI) is a clinical test to diagnose peripheral artery disease. The Wyatt's score has been proposed to assess the students' performance on ABI measurement on a healthy volunteer (HV). No study has shown that this score is sensitive to different teaching methods. In this randomized controlled trial, we wanted to determine whether didactic learning alone or didactic learning combined with experiential learning improves proficiency in the ABI procedure assessed by the Wyatt's score. METHODS: Medical students (n = 30) received a didactic learning, including (1) a presentation of the ABI guidelines and (2) a video demonstration. Each student was then randomized into 2 groups ("the no experiential learning group" and "the experiential learning group"). An initial evaluation was performed after the didactic learning and then the final evaluation at the end of the intervention. A student was considered to be proficient when he performed a correct ABI procedure on an HV. The correct procedure corresponds to the following: (1) correctly answered Wyatt's score and (2) a difference in the ABI measurement between a professor in vascular medicine and a student was ≤0.15. RESULTS: No student was proficient at the initial evaluation. At the final evaluation, there was a significant difference between the number of proficient students for the Wyatt's score depending on their learning group [didactic alone (1/10) or didactic + experiential training (15/20)] and also for the ABI procedure [didactic alone (0/10) or didactic + experiential training (16/20)]. At 6 months, among the 12 students who passed the final evaluation, 4 students passed both the Wyatt's score and the ABI measurement. CONCLUSIONS: Our study demonstrates that the Wyatt's score was sensitive to an educational intervention and no improvement was found in the case of "no experiential learning." The Wyatt's score could be used to evaluate the student on ABI measurement after an educational intervention. TRIAL REGISTRATION: A randomized controlled trial was conducted in the Vascular Medicine Department of Rennes University Hospital (France). This was approved by the ethics review board of our institution (no. 16.150).

Noninvasive Peripheral Artery Disease Screening Tools: A Deficient Knowledge among French Vascular Residents from 4 Medical Schools.

BACKGROUND: Ankle-brachial index (ABI) at rest, postexercise ABI, and toe-brachial index (TBI) are essential diagnostic tools recommended for peripheral artery disease (PAD) diagnosis. Our study investigates the level of knowledge on these 3 tests among vascular medicine residents from 4 French medical schools in France. METHODS: We included 19 vascular medicine residents in a cross-sectional study. During an annual obligatory seminar, all residents accepted to fill 3 questionnaires concerning knowledge about these 3 tests. RESULTS: All residents accepted to fill 3 questionnaires. None of the residents correctly knows how to perform all pressure measurements (ABI, postexercise ABI, and TBI). Two residents had the knowledge to perform the whole ABI at rest procedure, whereas no resident had the knowledge to perform neither the postexercise ABI (P = 0.48) nor the TBI (P = 0.48). Twelve residents correctly completed the question regarding the interpretation of ABI at rest, whereas 2 correctly completed the postexercise ABI question (P = 0.001) and 4 the TBI question (P = 0.02). The number of residents who have performed more than 20 measurements is higher regarding ABI at rest than postexercise ABI and TBI (84%, 5%, and 37% respectively; P < 0.001 and P = 0.006 respectively) and significantly less often in postexercise ABI than TBI (5% vs. 37%; P = 0.04). CONCLUSIONS: This study shows for the first time that residents' knowledge of pressure measurements (resting-ABI, postexercise ABI, and TBI) of 4 French medical school are insufficient although the importance of pressure measurement has been strongly highlighted by the newly released PAD guidelines (2016) for PAD diagnosis.

Heterogeneity of Doppler waveform description is decreased with the use of a dedicated classification.

BACKGROUND: The analysis of Doppler ultrasound waveforms (DW) provides a method for detecting and evaluating arterial stenosis in the lower limb arteries but no recommendation exists on how to describe the DWs. Aims of this study were to assess the heterogeneity of the description of DWs among vascular residents and the impact of the use of a 4-item classification. METHODS: Thirty different DWs were presented to residents using Microsoft PowerPoint® slides. They were invited to describe the 30 DWs before and after the presentation of a 4-item classification (triphasic, biphasic, monophasic, and others). The heterogeneity was assessed by the number of different answers used by the residents. Nineteen residents with six to eighteen months of vascular medicine training and ultrasound experience were included. RESULTS: The average of different answers was 9 ± 4 for the whole analysis of the 30 DWs without the use of a specific classification, whereas the average was 2 ± 1 using the 4-item classification (p < 0.005). There was a significant difference in correct answers, i. e. in combined continuous waveforms and pulsed waveforms between experienced residents and younger residents (p < 0.05). CONCLUSIONS: Using a 4-item classification for DWs reduced the heterogeneity of the DW description. There is an urgent need to standardize the DW description in order to improve the patients care with peripheral artery disease.

Atherosclerosis knowledge - diagnosis and management in primary care.

BACKGROUND: Atherosclerosis is the leading cause of death worldwide. Ischaemic stroke, coronary heart disease (CHD), and peripheral artery disease (PAD) are different forms of atherosclerotic disease. Knowledge among general practitioners (GPs) about the three main locations of atherosclerosis has never been conjointly explored in a single study. The aim of this survey was to compare GP awareness on the subject of these three different clinical presentations. MATERIALS AND METHODS: Between February 2017 and May 2017, a self-administered survey was emailed to 18,500 French GPs. The questionnaire comprised three clinical cases involving cases of transient ischaemic attack (TIA), stable angina (SA), and intermittent claudication (IC). Each case was explored with seven similar questions. The primary endpoint was the number of physicians who correctly answered five questions for each clinical case. RESULTS: The survey was completed by 1,724 GPs. TIA knowledge (48.2 %) was significantly higher than the SA knowledge (3.0 %) and IC knowledge (0.4 %). We also found a significant difference between SA knowledge and IC knowledge. The percentages of GPs who correctly diagnosed TIA, SA or IC were 96.7, 89.7, and 96.5 %, respectively (p < 0.0001). Poor knowledge ratings for all three locations were observed for inadequate prescription of supplementary investigations and treatments. CONCLUSIONS: Our study demonstrates that GPs' knowledge about atherosclerosis disease varies significantly depending on disease location. GPs diagnose correctly but need to be backed up for their management of patients with atherosclerosis.

The use of the tyrosine kinase inhibitor Nilotinib in Spondyloarthritis: does targeting inflammatory pathways with a treatment lead to vascular toxicity?

Spondylarthritis (SpA) is an inflammatory rheumatic disease associated with increased incidence of major adverse cardiovascular events (MACEs). Recently, Paramarta et al. proposed the use of the tyrosine kinase inhibitor Nilotinib in Spondyloarthritis to target certain inflammatory pathways. However, Nilotinib, which is highly effective for the treatment of patients with chronic myeloid leukaemia (CML), is also associated with an increased risk of MACEs. The authors suggest that Nilotinib may be effective in peripheral SpA by modulating inflammation, but not in axial SpA. Considering the vascular toxicity of Nilotinib and the acceleration of atherosclerosis in SpA patients, we suggest taking MACEs as an end-point in future trials.

Optimisation of movement detection and artifact removal during laser speckle contrast imaging.

INTRODUCTION: Laser speckle contrast imaging (LSCI) allows an easy non-contact monitoring of the cutaneous blood flow (CBF), but is highly sensitive to movement artifacts (ARTm). Subtraction of a signal recorded on an adhesive opaque surface (AOS) close to the area of interest was reported as a mean of reducing noise from the raw skin LSCI (LSCIsk) signal, provided an individual calibration was performed. Assuming that AOS=a·CBF+b·ARTm, an ideal patch should completely block the light reflection due to CBF and thus be insensitive to skin blood flow changes ("a"~0), while keeping a reflection signal amplitude similar to the one from the skin in case of artifact ("b"~1). This ideal AOS has not been determined and may discriminate flow from movements during LSCI recordings. MATERIALS AND METHODS: We tested different AOSs to determine their "a" and "b" parameters in 35 and 34 healthy volunteers, respectively. The AOS surface providing results as close as possible to an ideal AOS, was used for a point-by-point de-noising of post occlusive reactive hyperemia (PORH) on two different days in 15 new subjects. Correlation of raw, smoothed (average smoothing over 1s intervals) and denoised signals was tested through a cross-correlation analysis of the two POHR tests. RESULTS: The optimal "a" and "b" values were obtained with a homemade bilayer adhesive patch (a=0.06±0.05 and b=1.03±0.17) whereas other tested AOS had "a" values ranging from 0.05 to 0.23 and "b" values ranging from 2.69 to 3.82. Using the bilayer adhesive patch the cross-correlation between the two tests of POHR increased from 0.330±0.128 for raw, to 0.461±0.168 for smoothed and 0.649±0.128 for denoised signals respectively (p<0.05 from raw coefficients). CONCLUSION: The home-made bilayer adhesive seems the optimal AOS for the removal of ARTm from the LSCIsk signal while respecting CBF signal. This specific AOS allows for an efficient de-noising of LSCI measurements without the need for individual calibration.

The correlation of the "Walking Estimated-Limitation Calculated by History" (WELCH) questionnaire with treadmill maximal walking time is not impaired by age, in patients with claudication.

PURPOSE: The "Walking Estimated-Limitation Calculated by History" (WELCH) questionnaire is a short four-item questionnaire that estimates the walking capacity of a patient in comparison with relatives, friends or people the same age. As such, it should be relatively insensitive to age, yet this has never been tested. METHODS: A prospective study was performed among 525 patients presenting vascular-type claudication. Patients were grouped into quintiles of age-from quintile 1 for the youngest patients to quintile 5 for the oldest ones. Patients completed a self-administered questionnaire and then had their maximal walking time (MWT) measured on a treadmill. We estimated the coefficient of correlation, the slope and the intercept of the relationship between the WELCH score and the MWT, then the accuracy of a WELCH score under 25 to predict the ability to walk for 5 min on a treadmill. RESULTS: The slopes of the relationships and the correlation coefficients were not significantly different in each quintile, but a significant shift in the intercept of regressing lines was found with age. Nevertheless, the accuracy in predicting treadmill results from the WELCH score with a cut-off point of 25 was, respectively, 68.6, 72.4, 80.0, 72.4 and 73.3 % in quintiles 1, 2, 3, 4 and 5 (p = 0.45). CONCLUSIONS: The relationship of MWT on a treadmill and the WELCH score is slightly influenced by age, but a score superior to 25 seems to be of equal discriminatory performance in different quintiles of age to predict the ability to walk for 5 min on a treadmill. This makes this cut-off limit of interest for routine use, regardless of age.