Usefulness of the ratio of brachial pre-ejection period to brachial ejection time in prediction of cardiovascular and overall mortality in patients with acute myocardial infarction.

Left ventricular systolic function is a good indicator of cardiac function and a powerful predictor of adverse cardiovascular (CV) outcomes. High ratio of pre-ejection period (PEP) to ejection time (ET) is associated with reduced left ventricular systolic function. Brachial PEP (bPEP) and brachial ET (bET) can be automatically calculated from an ankle-brachial index (ABI)-form device and bPEP/bET was recently reported to be a new and useful parameter of cardiac performance. However, there were no studies evaluating the utility of bPEP/bET for prediction of CV and overall mortality in patients with acute myocardial infarction (AMI). We included 139 cases of AMI admitted to our cardiac care unit consecutively. ABI, bPEP, and bET were obtained from the ABI-form device within the 24 hours of admission. There were 87 overall and 22 CV mortality and the median follow-up to mortality event was 98 months. After multivariable analysis, high bPEP/bET was not only associated with increased long-term CV mortality (hazard ratio (HR) = 1.046; 95% confidence interval (CI): 1.005-1.088; P = 0.029), but also associated with long-term overall mortality (HR = 1.023; 95% CI: 1.001-1.045; P = 0.042). In addition, age was also a significant predictor for CV and overall mortality after the multivariable analysis. In conclusion, bPEP/bET was shown to be a significant predictor for CV and overall mortality in AMI patients after multivariable analysis. Therefore, by means of this novel parameter, we could easily find out the high-risk AMI patients with increased CV and overall mortality.

Re-evaluating the safety and effectiveness of the 0.9 ankle-brachial index threshold in penetrating lower extremity trauma.

OBJECTIVE: Current guidelines recommend additional imaging when the ankle-brachial index (ABI) is ≤0.9 after extremity trauma; however, the accuracy of this 0.9 threshold compared with other values has not been evaluated. The primary aim of this study was to compare the safety and effectiveness of various ABI thresholds in predicting lower extremity vascular injuries after penetrating trauma. We hypothesized that a lower ABI threshold can be used safely to avoid unnecessary imaging. METHODS: A retrospective cohort study was performed at a single level I trauma center from January 2015 to December 2017. All patients who presented with penetrating lower extremity trauma and who underwent computed tomography angiography (CTA) were reviewed. Patients taken directly to the operating room without first undergoing CTA or those without documented ABIs were excluded. Demographic information, clinical features of presentation, interventions performed, and outcomes were recorded. P values were obtained using the Kolmogorov-Smirnov test, and a receiver operating characteristic curve was created to compare various ABI thresholds. RESULTS: A total of 47 patients (81% male), with a mean age of 29 years (range, 14-59 years), met inclusion criteria. Of the 17 limbs (36%) with a vascular abnormality seen on CTA, 6 (35%) required an intervention. The distribution of ABIs in injured limbs requiring revascularization was significantly lower (P = .006) than in those that did not require intervention. An ABI threshold of 0.7 is most accurate, with the highest combined sensitivity (83%) and specificity (91%) for detecting vascular injuries requiring revascularization. In addition, the negative predictive value was no different between a threshold of 0.7 (98%) and a threshold of 0.9 (97%), with both thresholds missing one vascular injury (pseudoaneurysm) requiring repair. CONCLUSIONS: The ABI remains reliable in distinguishing between limbs with and limbs without vascular injury requiring revascularization after penetrating lower extremity trauma. A lower threshold can safely be used without compromising the negative predictive value of a screening ABI. Applying a threshold of 0.7 to our cohort would have avoided 51% (24) of the CTA studies performed without missing additional vascular injuries requiring repair.

Comparison of exercise oximetry and ankle pressure measurements for patients with intermittent claudication: an observational study of 433 patients.

To study the concordance of exercise-oximetry and of ankle-brachial pressure index (ABI) and ankle pressure (AP) at rest, and after exercise, in patients complaining of vascular-type claudication to diagnose lower extremity artery disease (LEAD). Treadmill test in 433 patients with exercise-oximetry included constant load (3.2 km/h, 10% slope) phase for up to 15 min followed by an increment phase, if necessary. The presence (TcpO2e+) or absence (TcpO2e-) of ischemia was a decrease of limb minus chest oxygen pressure change greater than or less than - 15 mmHg. The post-exercise ABI and AP were measured after another test of a maximum of 5 min except if resting-ABI < 0.90. LEAD was diagnosed (+) based on resting-ABI < 0.90, post-exercise ABI < 0.8∙resting-ABI, or a difference of 30 mmHg between post-exercise and resting AP, or diagnosis was considered negative for all other cases (-). The discrepancies between the exercise-oximetry and pressure results were analyzed. We found 351 patients with resting-ABI+, of whom 52 were classified as TcpO2e-. Of the 82 patients with resting-ABI-, 25 had post-exercise ABI+ or AP+, of whom, 10 had TcpO2e-, while 57 had post-exercise ABI- and AP-, of whom, 28 had TcpO2e+. Discrepancies arose mainly from nonvascular limitations, isolated proximal ischemia, and detection of LEAD in the incremental phase of the exercise-oximetry. Post-exercise pressure measurements were easy and useful, but exercise-oximetry provided additional information for both resting-ABI- and resting-ABI+ patients and can help to prove the vascular origin of walking limitation of LEAD patients.

Introducing the British Lymphology Society position paper on ankle brachial pressure index.

Prompt application of appropriate compression therapy is essential for effective treatment of lymphoedema. However, it is accepted that prior to the application of compression to the lower limbs, either with bandaging or compression garments, patients should demonstrate a satisfactory vascular status, as assessed via axillary brachial pressure index (ABPI). Unfortunately, the presence of peripheral oedema may render a reading impossible or grossly inaccurate. Relying solely on ABPI assessment is potentially harmful to patients, who may be denied appropriate treatment or experience complications and deterioration of their condition due to delayed treatment. The British Lymphology Society recognises a need to focus more on clinical assessment skills to determine vascular status, rather than relying on ABPI alone. Thus, the Society has developed guidance and a practical tool to support clinical decision-making and enhance practitioner confidence in the safe application of compression therapy in the absence of ABPI.

ABPI reporting and compression recommendations in global clinical practice guidelines on venous leg ulcer management: A scoping review.

Clinical practice guidelines (CPGs) for venous leg ulcer (VLU) management recommend below-knee compression to improve healing outcomes after calculating the ankle-brachial pressure index (ABPI) to rule out significant arterial disease. This systematic scoping review aimed to complete a qualitative and quantitative content analysis of international CPGs for VLU management to determine if consensus existed in relation to recommendations for compression application based on an ABPI reading and clinical assessment. Our review shows that there is a lack of consensus across 13 VLU CPGs and a lack of clear guidance in relation to the specific ABPI range of compression therapy that can be safely applied. An area of uncertainty and disagreement exists in relation to an ABPI between 0.6 and 0.8, with some guidelines advocating that compression is contraindicated and others that there should be reduced compression. This has implications in clinical practice, including when it is safe to apply compression. In addition, the inconsistency in the levels of evidence and the grades of recommendation makes it difficult to compare across various guidelines.

Limited Adherence to Peripheral Arterial Disease Guidelines and Suboptimal Ankle Brachial Index Reliability in Dutch Primary Care.

OBJECTIVE/BACKGROUND: The Dutch College of General Practitioners' guideline on peripheral arterial disease (PAD) provides clear recommendations on the management of PAD. An ankle brachial index (ABI) measurement, prescription of antiplatelet drugs and statins, and supervised exercise therapy (SET) for intermittent claudication (IC) are advised. The aims of this study were to determine the adherence of general practitioners (GPs) to their own guideline on PAD and to evaluate the reliability of primary care ABI measurements. METHODS: This was a cross-sectional study. All patients suspected of having symptomatic PAD who were referred by GPs to a large hospital in 2015 were evaluated regarding three of the guideline criteria: (i) ABI measurement; (ii) prescription of secondary prevention; (iii) initiation of SET. ABI values obtained in primary care and the hospital's vascular laboratory were compared using correlation coefficients and regression analysis. An abnormal ABI was defined as a value <.9 (normal ABI ≥.9). RESULTS: Of 308 potential patients with new onset PAD, 58% (n = 178) had undergone ABI measurement prior to referral. A modest correlation between ABI values obtained in primary care and the vascular laboratory was found (r = .63, p < .001). Furthermore, a moderate reliability was calculated (intraclass correlation coefficient 0.60, 95% confidence interval 0.49-0.69, p < .001). Of the new patients with an abnormal ABI, 59% used antiplatelet drugs and 55% used statins. A referral for SET was initiated by a GP in 10% of new PAD patients with IC symptoms. CONCLUSIONS: Adherence by Dutch GPs to their own society's PAD guideline has room for improvement. The reliability of ABI measurements is suboptimal, whereas rates of prescription of secondary prevention and initiation of SET as primary treatment for IC need upgrading.

Proposed Cutoff Value of Brachial-Ankle Pulse Wave Velocity for the Management of Hypertension.

BACKGROUND: The optimal cutoff values of the brachial-ankle pulse wave velocity (baPWV) for predicting cardiovascular disease (CVD) were examined in patients with hypertension.Methods and Results:A total of 7,656 participants were followed prospectively. The hazard ratio for the development of CVD increased significantly as the baPWV increased, independent of conventional risk factors. The receiver-operating characteristic curve analysis showed that the optimal cutoff values for predicting CVD was 18.3 m/s. This cutoff value significantly predicted THE incidence of CVD. CONCLUSIONS: The present analysis suggests that the optimal cutoff value for CVD in patients with hypertension is 18.3 m/s.

Accuracy of Physical Examination, Ankle-Brachial Index, and Ultrasonography in the Diagnosis of Arterial Injury in Patients With Penetrating Extremity Trauma: A Systematic Review and Meta-analysis.

BACKGROUND: Penetrating Extremity Trauma (PET) may result in arterial injury, a rare but limb- and life-threatening surgical emergency. Timely, accurate diagnosis is essential for potential intervention in order to prevent significant morbidity. OBJECTIVES: Using a systematic review/meta-analytic approach, we determined the utility of physical examination, Ankle-Brachial Index (ABI), and Ultrasonography (US) in the diagnosis of arterial injury in emergency department (ED) patients who have sustained PET. We applied a test-treatment threshold model to determine which evaluations may obviate CT Angiography (CTA). METHODS: We searched PubMed, Embase, and Scopus from inception to November 2016 for studies of ED patients with PET. We included studies on adult and pediatric subjects. We defined the reference standard to include CTA, catheter angiography, or surgical exploration. When low-risk patients did not undergo the reference standard, trials must have specified that patients were observed for at least 24 hours. We used the Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS-2) to evaluate bias and applicability of the included studies. We calculated positive and negative likelihood ratios (LR+ and LR-) of physical examination ("hard signs" of vascular injury), US, and ABI. Using established CTA test characteristics (sensitivity = 96.2%, specificity = 99.2%) and applying the Pauker-Kassirer method, we developed a test-treatment threshold model (testing threshold = 0.14%, treatment threshold = 72.9%). RESULTS: We included eight studies (n = 2,161, arterial injury prevalence = 15.5%). Studies had variable quality with most at high risk for partial and double verification bias. Some studies investigated multiple index tests: physical examination (hard signs) in three studies (n = 1,170), ABI in five studies (n = 1,040), and US in four studies (n = 173). Due to high heterogeneity (I2  > 75%) of the results, we could not calculate LR+ or LR- for hard signs or LR+ for ABI. The weighted prevalence of arterial injury for ABI was 14.3% and LR- was 0.59 (95% confidence interval [CI] = 0.48-0.71) resulting in a posttest probability of 9% for arterial injury. Ultrasonography had weighted prevalence of 18.9%, LR+ of 35.4 (95% CI = 8.3-151), and LR- of 0.24 (95% CI = 0.08-0.72); posttest probabilities for arterial injury were 89% and 5% after positive or negative US, respectively. The posttest probability of arterial injury with positive US (89%) exceeded the CTA treatment threshold (72.9%). The posttest probabilities of arterial injury with negative US (5%) and normal ABI (9%) exceeded the CTA testing threshold (0.14%). Normal examination (no hard or soft signs) with normal ABI in combination had LR- of 0.01 (95% CI = 0.0-0.10) resulting in an arterial injury posttest probability of 0%. CONCLUSIONS: In PET patients, positive US may obviate CTA. In patients with a normal examination (no hard or soft signs) and a normal ABI, arterial injury can be ruled out. However, a normal ABI or negative US cannot independently exclude arterial injury. Due to high study heterogeneity, we cannot make recommendations when hard signs are present or absent or when ABI is abnormal. In these situations, one should use clinical judgment to determine the need for further observation, CTA or catheter angiography, or surgical exploration.

Toe brachial index measured by automated device compared to duplex ultrasonography for detecting peripheral arterial disease in older people.

Introduction To investigate the diagnostic accuracy of an automated toe blood pressure device for detecting peripheral arterial disease in older people. Methods Ninety participants underwent toe and brachial blood pressure measurements and colour duplex ultrasonography of the right lower limb. Peripheral arterial disease was diagnosed if > 50% arterial obstruction was identified in any lower limb vessel using colour duplex ultrasonography. A receiver operating characteristic curve was analysed and the sensitivity and specificity of commonly used toe brachial index and toe blood pressure values were determined. Results The optimum toe brachial index threshold value for diagnosing peripheral arterial disease was 0.72 (sensitivity 76.2%, specificity 75%). The area under the curve was 0.829 (95% CI 0.743 to 0.915, p < 0.0001) suggesting fair diagnostic accuracy. A toe blood pressure of 70 mmHg was found to have excellent specificity (97.92%) for detecting PAD but poor sensitivity (42.86%). Conclusions The accuracy of automated toe blood pressure and TBI measurements was determined to be good when using colour duplex ultrasound as the reference standard for the non-invasive diagnosis of peripheral arterial disease. Results should be interpreted in the context of all clinical signs and symptoms.

Arterial stiffness in hypertensive and type 2 diabetes patients in Ghana: comparison of the cardio-ankle vascular index and central aortic techniques.

BACKGROUND: Diabetes and hypertension increase arterial stiffness and cardiovascular events in all societies studied so far; sub-Saharan African studies are sparse. We investigated factors affecting arterial function in Ghanaians with diabetes, hypertension, both or neither. METHOD: Testing the hypothesis that arterial stiffness would progressively increase from controls to multiply affected patients, 270 participants were stratified into those with diabetes or hypertension only, with both, or without either. Cardio-ankle vascular index (CAVI), heart-ankle pulse wave velocity (haPWV), aortic PWV (PWVao) by Arteriograph, aortic and brachial blood pressures (BP), were measured. RESULTS: In patients with both diabetes and hypertension compared with either alone, values were higher of CAVI (mean ± SD, 8.3 ± 1.2 vs 7.5 ± 1.1 and 7.4 ± 1.1 units; p < 0.05), PWVao (9.1 ± 1.4 vs 8.7 ± 1.9 and 8.1 ± 0.9 m/s; p < 0.05) and haPWV (8.5 ± 1 vs 7.9 ± 1 and 7.2 ± 0.7 m/s; p < 0.05) respectively. In multivariate analysis, age, having diabetes or hypertension and BMI were independently associated with CAVI in all participants (ß = 0.49, 0.2, 0.17 and -0.2 units; p < 0.01, respectively). Independent determinants of PWVao were heart rate, systolic BP and age (ß = 0.42, 0.27 and 0.22; p < 0.01), and for haPWV were systolic BP, age, BMI, diabetes and hypertension status (ß = 0.46, 0.32, -0.2, 0.2 and 0.11; p < 0.01). CONCLUSION: In this sub-Saharan setting with lesser atherosclerosis than the western world, arterial stiffness is significantly greater in patients with coexistent diabetes and hypertension but did not differ between those with either diabetes or hypertension only. Simple, reproducibly measured PWV/CAVI may offer effective and efficient targets for intervention.

Independent and Joint Effect of Brachial-Ankle Pulse Wave Velocity and Blood Pressure Control on Incident Stroke in Hypertensive Adults.

Pulse wave velocity (PWV) has been shown to influence the effects of antihypertensive drugs in the prevention of cardiovascular diseases. Data are limited on whether PWV is an independent predictor of stroke above and beyond hypertension control. This longitudinal analysis examined the independent and joint effect of brachial-ankle PWV (baPWV) with hypertension control on the risk of first stroke. This report included 3310 hypertensive adults, a subset of the China Stroke Primary Prevention Trial (CSPPT) with baseline measurements for baPWV. During a median follow-up of 4.5 years, 111 participants developed first stroke. The risk of stroke was higher among participants with baPWV in the highest quartile than among those in the lower quartiles (6.3% versus 2.4%; hazard ratio, 1.66; 95% confidence interval, 1.06-2.60). Similarly, the participants with inadequate hypertension control had a higher risk of stroke than those with adequate control (5.1% versus 1.8%; hazard ratio, 2.32; 95% confidence interval, 1.49-3.61). When baPWV and hypertension control were examined jointly, participants in the highest baPWV quartile and with inadequate hypertension control had the highest risk of stroke compared with their counterparts (7.5% versus 1.3%; hazard ratio, 3.57; 95% confidence interval, 1.88-6.77). There was a significant and independent effect of high baPWV on stroke as shown among participants with adequate hypertension control (4.2% versus 1.3%; hazard ratio, 2.29, 95% confidence interval, 1.09-4.81). In summary, among hypertensive patients, baPWV and hypertension control were found to independently and jointly affect the risk of first stroke. Participants with high baPWV and inadequate hypertension control had the highest risk of stroke compared with other groups.

An analysis of IN.PACT DEEP randomized trial on the limitations of the societal guidelines-recommended hemodynamic parameters to diagnose critical limb ischemia.

OBJECTIVE: Recent small single-center data indicate that the current hemodynamic parameters used to diagnose critical limb ischemia are insensitive. We investigated the validity of the societal guidelines-recommended hemodynamic parameters against core laboratory-adjudicated angiographic data from the multicenter IN.PACT DEEP (RandomIzed AmPhirion DEEP DEB vs StAndard PTA for the treatment of below the knee Critical limb ischemia) Trial. METHODS: Of the 358 patients in the IN.PACT DEEP Trial to assess drug-eluting balloon vs standard balloon angioplasty for infrapopliteal disease, 237 had isolated infrapopliteal disease with an available ankle-brachial index (ABI), and only 40 of the latter had available toe pressure measurements. The associations between ABI, ankle pressure, and toe pressure with tibial runoff, Rutherford category, and plantar arch were examined according to the cutoff points recommended by the societal guidelines. Abnormal tibial runoff was defined as severely stenotic (≥70%) or occluded and scored as one-, two-, or three-vessel disease. A stenotic or occluded plantar arch was considered abnormal. RESULTS: Only 14 of 237 patients (6%) had an ABI <0.4. Abnormal ankle pressure, defined as <50 mm Hg if Rutherford category 4 and <70 mm Hg if Rutherford category 5 or 6, was found only in 37 patients (16%). Abnormal toe pressure, defined as <30 mm Hg if Rutherford category 4 and <50 mm Hg if Rutherford category 5 or 6, was found in 24 of 40 patients (60%) with available measurements. Importantly, 29% of these 24 patients had an ABI within normal reference ranges. A univariate multinomial logistic regression found no association between the above hemodynamic parameters and the number of diseased infrapopliteal vessels. However, there was a significant paradoxic association where patients with Rutherford category 6 had higher ABI and ankle pressure than those with Rutherford category 5. Similarly, there was no association between ABI and pedal arch patency. CONCLUSIONS: The current recommended hemodynamic parameters fail to identify a significant portion of patients with lower extremity ulcers and angiographically proven severe disease. Toe pressure has better sensitivity and should be considered in all patients with critical limb ischemia.

Transcutaneous oxygen tension measurements following peripheral transluminal angioplasty procedure has more specificity and sensitivity than ankle brachial index.

OBJECTIVE: To evaluate the superiority of transcutaneous oxygen pressure (TcPO2) before, during and after peripheral transluminal angioplasty (PTA) in comparison with ankle brachial index (ABI) in patients with diabetes. METHODS: 40 consecutive patients with diabetes treated by PTA where included. This study shows results before, during and after PTA and their progression for 8 weeks. RESULTS: The TcPO2 increased from 28.11 ± 8.1 to 48.03 ± 8.4 mmHg, 8 weeks after PTA (p < 0.001). The ABI increased from 0.48 ± 0.38 to 0.77 ± 0.39 after PTA (p < 0.001). After PTA, the stenosis of the vessel decreased from 58.33 ± 20.07% to 21.87 ± 13.57% (p < 0.001). TcPO2 was determined in all the patients, but ABI could not be determined in all patients. Furthermore, we determined patients with "false negatives" with an improvement in ABI and "false positives" in 12.5% of patients. Additionally, in this study, we monitored TcPO2 while performing PTA, revealing variations in each phase of the radiological procedure. CONCLUSION: The increase in TcPO2 measurements following PTA procedure has more specificity and sensitivity than does ABI. The use of TcPO2 may represent a more accurate alternative than traditional methods (ABI) used in assessing PTA results. The TcPO2 also allows the radiologist to assess changes in tissue oxygenation during PTA, allowing changes to the procedure and subsequent treatment. ADVANCES IN KNOWLEDGE: This is the first time that a graph is shown with TcPO2 results during PTA performance in many patients.

Time and reliability issues associated with automatic vs. manual measurements of Ankle to Brachial pressure Index (ABI) following heavy load exercise.

OBJECTIVES: Ankle to brachial index after heavy load exercise is the most accurate way of diagnosing minor arterial lesions in athletes, such as endofibrosis. The reliability and practical aspects of ankle to brachial index measurements after heavy-load exercise have not been studied. The purpose of this study was to analyze the interest of oscillometric automatic vs. manual Doppler measurements, for the calculation of ankle to brachial index, after heavy-load exercise in athletes. DESIGN: Prospective single-center study. METHODS: Fifteen healthy trained athletes performed an incremental test twice. Ankle to brachial index measurements were performed at Rest, as soon as possible after exercise (Rec-0), and then started at the 3rd minute of recovery (Rec-3), by two operators using each one of the two ankle to brachial index measurement methods. RESULTS: Mean times for automatic vs. manual ankle to brachial availability were 99 ± 18 s vs. 113 ± 25 s (p = 0.005) and 44 ± 25 s vs. 53 ± 12 s (p = 0.001) respectively at Rec-0 and Rec-3. Ankle to brachial index values from the two methods were highly correlated (r = 0.89). Mean absolute differences of automatic vs. manual ankle to brachial values from test-retest were 0.04 ± 0.05 vs. 0.08 ± 0.08 (p > 0.05) and 0.07 ± 0.05 vs. 0.09 ± 0.10 (p > 0.05) at Rest and Rec-0. CONCLUSIONS: Automatic method allows obtaining faster and simultaneously post-exercise ankle to brachial index measurement compare to the manual Doppler. This time issue does not result in a significant change in absolute ankle to brachial index values, nor in the absolute differences of these in test-retest. Nevertheless, the test-retest variability of post-exercise ankle to brachial index results seems smaller with the automatic than the manual method.

Lymphocyte-to-monocyte ratio: a novel marker for critical limb ischemia in PAOD patients.

BACKGROUND: The lymphocyte-to-monocyte ratio (LMR) is easily determined from the white blood cell count. Lymphocytes were previously investigated as a part of the neutrophil-to-lymphocyte ratio (NLR) in patients with atherosclerotic disease and an elevated NLR was negatively associated with cardiovascular endpoints. As monocytes play a leading role in the progression of atherosclerosis, especially in peripheral arterial occlusive disease (PAOD), we investigated LMR and its association with critical limb ischemia and other vascular endpoints in PAOD patients. METHODS AND FINDINGS: We evaluated 2121 PAOD patients treated at our institution from 2005 to 2010. LMR was calculated and the cohort was divided into tertiles according to the LMR. An optimal cut-off value for the continuous LMR was calculated by applying a receiver operating curve analysis to discriminate between CLI and non-CLI. In our cohort occurrence of CLI decreased significantly with an increase in LMR. An LMR of 3.1 was identified as an optimal cut-off. Two groups were categorized, one with 1021 patients (LMR < 3.1) and a second one with 1100 patients (LMR ≥ 3.1). CLI was more frequent in LMR < 3.1 patients [426 (41.7%)] than in LMR ≥ 3.1 patients [254 (23.1%)] (p < 0.001), as was also the case with prior myocardial infarction [60 (9.5%) vs. 35 (3.2%), p = 0.003] and congestive heart failure [136 (13.3%) vs. 66 (6.0%), p < 0.001). As to inflammatory parameters, C-reactive protein [median 9.0 mg/l (4.0-30.0) vs. median 4.0 mg/l (2.0-8.0)] and fibrinogen (median 438 mg/dl (350-563) vs. 372 mg/dl (316-459.5)] also differed significantly in the two patient groups (both p < 0.001). A LMR < 3.1 was associated with an odds ratio (OR) of 2.0 (95% CI 1.8-2.2, p < 0.001) for CLI, even after adjustment for other vascular risk factors. CONCLUSIONS: A decreased LMR is significantly associated with a high risk for CLI and other vascular endpoints. The LMR is an easily determinable, broadly available and inexpensive marker that could be used to identify patients at high risk for vascular endpoints.

A systematic review of the effect of pre-test rest duration on toe and ankle systolic blood pressure measurements.

BACKGROUND: Measurement of toe and ankle blood pressure is commonly used to evaluate peripheral vascular status, yet the pre-test rest period is inconsistent in published studies and among practitioners, and could affect results. The aim of this systematic review is to evaluate all research that has investigated the effect of different periods of pre-test rest on toe and ankle systolic blood pressure. METHODS: The following databases were searched up to April 2012: Medline (from 1946), EMBASE (from 1947), CINAHL (from 1937), and Cochrane Central Register of Controlled Trials (CENTRAL) (from 1800). No language or publication restrictions were applied. Eighty-eight content experts and researchers in the field were contacted by email to assist in the identification of published, unpublished, and ongoing studies. Studies evaluating the effect of two or more pre-test rest durations on toe or ankle systolic blood pressure were eligible for inclusion. No restrictions were placed on participant characteristics or the method of blood pressure measurement. Outcomes included toe or ankle systolic blood pressure and adverse effects. Abstracts identified from the search terms were independently assessed by two reviewers for potential inclusion. RESULTS: 1658 abstracts were identified by electronic searching. Of the 88 content experts and researchers in the field contacted by email a total of 33 replied and identified five potentially relevant studies. No studies were eligible for inclusion. CONCLUSIONS: There is no evidence of the effect of different periods of pre-test rest duration on toe and ankle systolic blood pressure measurements. Rigorous trials evaluating the effect of different durations of pre-test rest are required to direct clinical practice and research.

Validity, intra- and inter-observer reliability of automated devices for the assessment of ankle brachial index using photo-plethysmography.

BACKGROUND: Ankle-brachial-Index (ABI) measured by manual Dopplersonography is an easily assessable marker of global cardiovascular risk. The aim of this study was to establish novel photo-plethysmography (PPG)-based ABI assessments in an epidemiologic context and to compare its results with those of Doppler. METHODS: Two devices for PPG-based ABI assessments (Vicorder, Vascular Explorer) were tested and compared against Doppler in 56 putatively healthy subjects. We determined acceptance, time requirements, agreement of repeat measurements, agreement with Doppler and intra- and inter-observer concordances for both devices and compared the results. Differences between cuff inflation- and deflation-based methods were also studied for Vascular Explorer. RESULTS: Acceptance was similar for both devices but Vascular Explorer was more time consuming. Agreement of multiple measurements was moderate for both methods highlighting the importance of measurement replicates. Both automated devices showed significantly higher ABI compared to Doppler which can be traced back to higher brachial pressures (Vicorder) or higher ankle pressures (Vascular Explorer). This effect is more pronounced for Vascular Explorer but can be ameliorated using the deflation method of measurement. Intra-observer concordances were similar. Inter-observer concordance was non-significantly better for Vicorder. CONCLUSIONS: Both devices proved to be feasible in epidemiologic studies, but compared to Doppler, do not constitute an advantage regarding time requirement and accuracy of ABI assessment. Since PPG-based ABI values are inflated compared to Doppler, it will be necessary to adjust Doppler-based cut-offs for risk stratification.