Normal Ankle-brachial Index Research Articles

Abstract 12934: The Impact of Peripheral Artery Disease Assessed by Ankle-Brachial Index on Endothelial Dysfunction and Risk of In-Stent Restenosis After Percutaneous Coronary Intervention

Introduction: The problem of in-stent restenosis (ISR) after percutaneous coronary intervention (PCI) remains unresolved. Patients with peripheral artery disease (PAD), defined as a decreased ankle brachial index (ABI), have high cardiovascular event rates and impaired endothelial function predicts future cardiovascular events. However, to our knowledge, no studies have assessed the relationship among ABI, endothelial dysfunction, and ISR after PCI. Hypothesis: We assessed the hypothesis that low ABI at PCI is associated with a high incidence of ISR. Methods: ABI and endothelial function were checked before PCI and at follow-up (F/U) angiography in 243 consecutive patients who had successful PCI. Endothelial function was assessed by measuring the reactive hyperemia index (RHI) from fingertip using a RH-PAT device. Patients were categorized according to their ABI values (PAD: ABI≦0.9, borderline: 0.9<ABI50% at F/U angiography assessed by quantitative coronary angiography. Results: Within the study population there were 27 PAD, 26 borderline, and 190 normal ABI at the index PCI. Among them, ISR was demonstrated in 68 patients (28%). As the PAD status become worse, patients were found to have significantly higher ISR rate (PAD: 52%, borderline: 35%, normal: 24%, p=0.02) and more impaired peripheral endothelial function assessed by RHI (PAD: 1.49±0.44, borderline: 1.77±0.41, normal: 1.97±0.52, p=0.0001). Furthermore, patients with ISR were found to have significantly lower ABI than those without ISR (1.05±0.15 vs. 1.11±0.13 p=0.004). By multivariate logistic regression analysis even after adjusting for other significant parameters in univariate analysis (BMS use, Calcium antagonist use, MLD post PCI, Total stent length, right coronary artery stenting, current smoking, HDL-Cholesterol, and ACS presentation), PAD proved to be the independent predictor of ISR (Odds ratio 3.32; 95% confidence interval; 1.29 to 8.54, p=0.01). Conclusions: In patients undergoing PCI, PAD is independently associated with a higher rate of subsequent ISR. Impaired endothelial dysfunction may contribute to this adverse outcome. These findings have important implications for the careful F/U of PAD patients undergoing PCI as ISR-prone patients.

Outcome of patients with reduced ankle brachial index undergoing open heart surgery with cardiopulmonary bypass.

In open heart surgery using cardiopulmonary bypass, perfusion of the lower extremities is markedly reduced which may induce critical ischaemia in patients with pre-existing peripheral artery disease. Whether these patients have an increased risk for amputation and should better undergo peripheral revascularization prior to surgery remains unclear. From 1 January 2009 to 31 December 2010, 785 consecutive patients undergoing open heart surgery were retrospectively included. In 443 of these patients, preoperative ankle brachial index (ABI) measurements were available. The cohort was divided into four groups: (i) ABI < 0.5, (ii) ABI 0.5-0.69, (iii) ABI 0.7-0.89 or (iv) ABI ≥ 0.9. Follow-up data of 413 (93.2%) patients were analysed with regard to mortality and amputations. The groups differed significantly in terms of age, cardiac risk factors, performed cardiac surgery and renal function. Postoperative delayed wound healing was significantly associated with lower ABI (25.9, 15.2, 27.0 and 9.6% in Groups I-IV, respectively, P = 0.003), whereas 30-day mortality was not significantly higher in patients with lower ABI (0, 4.3, 8.1 and 3.9%, respectively, P = 0.4). Kaplan-Meier models showed a significantly lower long-term survival over 4 years in patients with reduced ABI (P = 0.001, long-rank test) while amputations occurred rarely with only one minor amputation in Group II (P = 0.023). Patients with reduced ABIs undergoing heart surgery showed more wound-healing disturbances, and higher long-term mortality compared with those with normal ABIs. However, no perioperative ischaemia requiring amputation occurred. Thus, reduced ABIs were not associated with increased peripheral risks in open heart surgery but ABI may be helpful in selecting the site for saphenectomy to potentially avoid delayed healing of related wounds in legs with severely impaired arterial perfusion.

Metabolic syndrome and incident peripheral artery disease – the Multi-Ethnic Study of Atherosclerosis

ObjectiveWe evaluated whether metabolic syndrome (MetS) is associated with an increased incidence of lower extremity peripheral artery disease (PAD) in community dwelling people free of clinical cardiovascular disease at baseline. We assessed whether higher levels of inflammatory biomarkers may mediate the association of MetS with incident PAD. MethodsMetS was defined at baseline as the presence of three or more of the following components: elevated waist circumference, triglycerides ≥150 mg/dL, reduced high-density lipoprotein (HDL) cholesterol, blood pressure ≥130/85 mm Hg or taking blood pressure medication, and fasting glucose ≥100 mg/dL and <126 mg/dL. People with diabetes were excluded. Incident New PAD was defined among people with a normal ankle brachial index (ABI) at baseline (i.e. baseline ABI of 0.90 to 1.40) and consisted of one of the following outcomes during 3-year follow-up: ABI decline to < 0.90 combined with a decline ≥0.15 or medical record confirmed PAD outcome. Multivariable Poisson regression was used to estimate the association between MetS and incident PAD. ResultsAmong 4817 participants without PAD at baseline, 1382 (29%) had MetS. Adjusting for age, sex, race, smoking, physical activity, low-density lipoprotein cholesterol, baseline ABI, and other confounders, 23/1382 (1.7%) people with MetS developed PAD vs. 30/3435 (0.87%) people without MetS (risk ratio = 1.78 [95% Confidence Interval (CI), 1.04 to 2.82], P = 0.031). Adjusting for C-reactive protein, fibrinogen, or interleukin-6 did not attenuate this association. ConclusionPeople free of clinical cardiovascular disease with MetS are at increased risk for PAD. Our findings suggest that this association is not mediated by inflammation.

What Is the Clinical Utility of the Ankle-Brachial Index in Patients With Diabetic Foot Ulcers and Radiographic Arterial Calcification?

The purpose of this study was to analyze the influence of radiographic arterial calcification (RAC) on the clinical interpretation of ankle-brachial index (ABI) values in patients with diabetic foot ulcers. We analyzed a retrospective clinical database of 60 patients with diabetic foot ulcers from the Diabetic Foot Unit (Complutense University, Madrid, Spain) between January 2012 and March 2014. For each patient, anteroposterior XR-plains were evaluated, and the ABI and toe-brachial index (TBI) were assessed by an experienced clinician. To analyze the correlation among quantitative variables, we applied the Pearson correlation coefficient. Fifty percent (n = 9/18) of our patients with a normal ABI and RAC had a TBI < 0.7 associated with peripheral arterial disease (PAD). In patients with RAC, the prevalence of a normal ABI (72%, 18/25) was higher than in patients without RAC (52%, 11/21). The Pearson correlation coefficient among the ABI and TBI in patients with an ABI < 1.4 (n = 46) was lesser (r = .484, P = .001) than in patients with an ABI < 1.4 but without RAC (n = 21; r = .686, P = .001). ABI values between 0.9 and 1.4 would be falsely considered as normal and could underestimate the prevalence of PAD, especially in patients with neuropathy, diabetic foot ulcers, or RAC.

Borderline ankle-brachial index is associated with increased prevalence of micro- and macrovascular complications in type 2 diabetes: A cross-sectional analysis of 12,772 patients from the Joint Asia Diabetes Evaluation Program.

Borderline ankle-brachial index is increasingly recognised as a marker of cardiovascular risk. We evaluated the impact of borderline ankle-brachial index in 12,772 Chinese type 2 diabetes patients from the Joint Asia Diabetes Evaluation Program between 2007 and 2012. Cardiovascular risk factors, complications and health-related quality of life were compared between patients with normal ankle-brachial index (1.0-1.4), borderline ankle-brachial index (0.90-0.99) and peripheral arterial disease (ankle-brachial index < 0.9). The prevalence of peripheral arterial disease and borderline ankle-brachial index was 4.6% and 9.6%, respectively. Borderline ankle-brachial index patients were older, more likely to be smokers and hypertensive, had longer duration of diabetes, poorer kidney function and poorer health-related quality of life than patients with normal ankle-brachial index. After adjustment for traditional cardiovascular risk factors, borderline ankle-brachial index was an independent predictor of diabetes-related micro- and macrovascular complications including retinopathy (odd ratios: 1.19 (95% confidence interval: 1.04-1.37)), macroalbuminuria (1.31 (1.10-1.56)), chronic kidney disease (1.22 (1.00-1.50)) and stroke (1.31 (1.05-1.64)). These findings suggest that patients with diabetes and borderline ankle-brachial index are at increased cardiovascular risk and may benefit from more intensive management.

RR9. Characterization of Tibial Velocities by Duplex Ultrasound in Severe Peripheral Arterial Disease and Healthy Controls

The relationship between tibial velocities and peripheral arterial disease (PAD) severity is not well understood. We sought to characterize tibial velocities in patients with critical limb ischemia (CLI) or lifestyle-limiting claudication (LLC) and in healthy control patients without PAD. Patients with an arterial duplex ultrasound (DUS) with PAD (CLI or LLC) evaluated over a 5-year period were retrospectively compared with controls, patients without PAD, and a normal ankle-brachial index (ABI; 0.9-1.2). Control duplex ultrasound images were collected sequentially over a 60-month period. LLC was defined as short-distance claudication, objective PAD, and symptoms warranting revascularization. CLI was defined as ischemic rest pain or nonhealing ulcer/gangrene. For each artery, measurements were obtained at the proximal, middle, and distal portion of the vessel and averaged for each artery. Mean peak systolic velocities (PSV in cm/s), ABIs, peak ankle velocity (PAV), defined as the maximum PSV of any portion of the posterior tibial (PT) or anterior tibial (AT) artery, and average ankle velocity (AAV, the mean of the AT and PT PSV) were compared using independent t-tests. Preoperative DUS was available in 90 patients with PAD (54 CLI, 36 LLC) and 71 healthy controls. Mean ABI in the PAD group was 0.66 compared with 1.08 in controls. Mean PSV in PAD was significantly lower than controls at the popliteal (63.6 vs 76.2, P = .020), peroneal (33.9 vs 53.8, P < .001), AT (43.2 vs 65.4, P < .001), and PT artery (42.9 vs 74.1, P < .001). PAV (56.5 vs 89.2, P < .001) and AAV (43.5 vs 69.7, P < .001) were also significantly lower in the PAD group than in controls, whereas velocities in the profunda femoris artery were significantly higher in PAD group (132.1 vs 96.2, P = .001). From this, 95% confidence interval reference ranges were established for severe PAD and healthy controls (Table). This is the first study to characterize lower extremity arterial PSVs, PAVs and AAVs in severe PAD and healthy, non-PAD patients. These early criteria establish reference ranges to guide clinical decision-making and vascular lab interpretation.TableConfidence intervals in critical limb ischemia (CLI) and lifestyle-limiting claudication (LLC) compared with healthy nonperipheral arterial disease (PAD) patientsCLI and LLC (cm/s)Healthy controls (cm/s)PArtery Common femoral116.9-146.8111.3-133.0NS Profunda femoris115.0-149.285.5-106.9.001 Superficial femoral103.3-137.296.4-113.5NS Popliteal55.5-71.869.1-83.2<.001 Anterior tibial36.6-49.759.4-71.3<.001 Peroneal28.3-39.648.3-59.4<.001 Posterior tibial34.2– 51.666.9-81.3<.001Alternate parameters PAV AT46.6-69.470.4-86.1<.001 PAV PT41.3-71.879.4-99.0<.001 PAV Peroneal36.5-50.658.7-72.1<.001 AAV37.1-49.963.7-75.7<.001AAV, average ankle velocity; AT, anterior tibial; NS, not significant (P > .05); PAV, peak ankle velocity; PI, posterior tibial. Open table in a new tab

Association between functional performance and executive cognitive functions in an elderly population including patients with low ankle-brachial index.

IntroductionPeripheral arterial disease, as measured by the ankle–brachial index (ABI), is prevalent among the elderly, and is associated with functional performance, assessed by the 6-minute walk test (6MWT). Executive cognitive function (ECF) impairments are also prevalent in this population, but no existing study has investigated the association between ECF and functional performance in an elderly population including individuals with low ABI.AimTo investigate the association between functional performance, as measured by the 6MWT, and loss in ECF, in an elderly sample including individuals with low ABI.MethodThe ABI group was formed by 26 elderly individuals with low ABI (mean ABI: 0.63±0.19), and the control group was formed by 40 elderly individuals with normal ABI (mean ABI: 1.08±0.07). We analyzed functional performance using the 6MWT, global cognition using the Mini-Mental State Examination (MMSE), and ECF using the Digit Span for assessing attention span and working memory, the Stroop Color Word Test (SCWT) for assessing information processing speed and inhibitory control/impulsivity, and the Controlled Oral Word Association Test (COWAT) for assessing semantic verbal fluency and phonemic verbal fluency. We also used a factor analysis on all of the ECF tests (global ECF).ResultsBefore adjustment, the ABI group performed worse on global cognition, attention span, working memory, inhibitory control/impulsivity, semantic verbal fluency, and phonemic verbal fluency. After adjustment, the ABI group performance remained worse for working memory and semantic verbal fluency. In a simple correlation analysis including all of the subjects, the 6MWT was associated with global cognition, attention span, working memory, information processing speed, inhibitory control/impulsivity, semantic verbal fluency, and global ECF. After adjustment, all the associations remained statistically significant.ConclusionThis study found an independent association between functional performance and ECF in an elderly population including low ABI individuals, showing that, in elderly populations with functional impairment, ECF may also be impaired.

Cyclophilin A is associated with peripheral artery disease and chronic kidney disease in geriatrics: The Tianliao Old People (TOP) study.

Cyclophilin A (CyPA), secreted by vascular smooth muscle cells in response to oxidative stress, is important in the pathogenesis of progressive peripheral arterial occlusion disease (PAOD), which is common among chronic kidney disease. We explored the prevalence of PAOD in Taiwan’s elderly (≥ 65 years old) population and its association with CyPA and renal function. Residents of Tianliao District, a rural community in southern Taiwan, were surveyed. An ankle-brachial index (ABI) < 0.91 was defined as PAOD. Chronic kidney disease (CKD) was defined based on eGFR levels < 60 mL/min/1.73 m2. Serum CyPA was measured. Of the 473 participants, 68 (14.4%) had PAOD. Multiple logistic regression analysis showed PAOD was significantly associated with lower eGFR, lower BMI, higher glycated hemoglobin and higher pulse pressure. Serum CyPA levels in participants with PAOD were significantly higher than those with normal ABI values (47.3 ± 0.4 vs. 25.5 ± 0.2 ng/mL, p < 0.001). Moreover, eGFR inversely correlated with serum CyPA level (p < 0.05) in participants with CKD, but not in participants with normal renal function. In conclusion, with a prevalence of PAOD as high as 14.4% in an elderly community, CyPA might be the link between PAOD and advanced impaired renal function.

Relation of the Ankle Brachial Index (ABI) to left ventricular systolic function in patients with coronary artery disease

Background: Atherosclerosis is a diffuse disease process, being present in one vascular bed predicts its presence in the others. Ankle –Brachial Pressure Index (ABI) is a simple index related to the extent of atherosclerosis in coronary and noncoronary arterial beds, reflecting generalized atherosclerosis.Objectives: the aim of this study is to evaluate the relation of ABI to left ventricular systolic function using echocardiography in patients with coronary artery disease (CAD).Patients and Methods: Sixty seven patients (67) with CAD of either sex (70% males) with mean age 58± 6 years enrolled in this study, from December 2013 till May 2014; all were referred to the Iraqi Centre for Heart Disease (I.C.H.D.) for further evaluation and management. The ABI for each leg was calculated by dividing the lowest value of the ankle systolic blood pressure (SBP) (over both dorsalis pedis and posterior tibial arteries) by the highest value of either brachial SBP by using a Doppler ultrasound. The lower of the two values was used to define the patient ABI. The ejection fraction (EF) % and fractional shortening (FS) % were determined by using trans-thoracic echocardiography. Participants were divided into two groups according to ABI results: Group І: 29 patients with abnormal low ABI (ABI ≤ 0.90) with ABI mean of 0.79±0.12 and Group ІІ: 38 patients with normal ABI (0.9&lt; ABI ≤1.30) with ABI mean of 1.03±0.10 as a control group.Results: There were no statistically significant differences in statistics between the two groups regarding risk factors for atherosclerosis. EF% was significantly lower in group I than those in group II in such a way that the mean values of EF% was 53.41±14.72 for group I vs. 63.11±8.93 for group II with the p value = 0.003. Also ABI is correlated with the severity of left ventricular systolic dysfunction.Conclusion: ABI is a useful bedside clinical test that predicts and assess left ventricular systolic dysfunction in patients with coronary artery disease.

Abstract P160: Ankle-Brachial Index and Fracture Hospitalization in Middle-Aged Adults: The Atherosclerosis Risk in Communities (ARIC) Study

Background: Several studies indicate that lower extremity peripheral artery disease (PAD), commonly defined by an ankle-brachial index (ABI) &lt;0.9, can increase the risk of bone fracture via its impact on physical function and mobility. Because the majority of prior studies are limited to older white male populations (age ≥65 years), uncertainty remains regarding this association in non-whites, women, and younger individuals. Methods: We studied 15,160 ARIC participants (age 45-64 years in 1987-1989) whose ABI was measured in a randomly selected leg at baseline. Hip or lower extremity fracture-related diagnostic codes were identified through active surveillance of hospitalizations. We used Cox proportional hazards to estimate the independent association between ABI including high ABI (≥1.4), a condition shown in PAD with vascular stiffness, and incident fracture hospitalization, adjusting for potential confounders. Results: There were 668 hip or lower extremity fracture hospitalizations during a median follow-up of 22 years. In the crude model, there was a dose-response relationship between low ABI and fracture risk (Table). However, only ABI 0.9-1.1 remained statistically significant after demographic adjustment compared to normal ABI (1.1-1.4) and inclusion of other covariates rendered this association non-significant. The results were largely consistent among most demographic and clinical subgroups, but we observed increased risk of fracture in low ABI (&lt;0.9) among those with history of cardiovascular disease and high ABI (≥1.4) in men, in the fully adjusted model. Conclusion: An independent association of ABI with increased risk of hip or lower extremity fracture hospitalization was not that evident overall in our biracial population of middle-aged adults. However, ABI may contribute to increased risk of fracture in subgroups, warranting further investigation.

High Ankle-Brachial Index Indicates Cardiovascular and Peripheral Arterial Disease in Patients With Type 2 Diabetes.

We assessed the association between high ankle-brachial index (ABI) and cardiovascular disease (CVD) and peripheral arterial disease (PAD) in Chinese patients with type 2 diabetes mellitus (T2DM). The ABI was measured, and foot inspection was performed in 2080 outpatients with T2DM. The clinical characters in different ABI levels were analyzed, and the diagnostic value of high ABI to CVD and PAD was determined. Compared with the normal ABI group, the high ABI (>1.3) group had a higher prevalence of CVD and PAD but less than the low ABI (≤0.9) group. High ABI was an independent risk factor for the development of CVD and PAD. Receiver-operating characteristic curve analysis showed that the optimal cutoff of high ABI to predict CVD and PAD was 1.43 and 1.45, respectively. The odds ratio of high ABI for CVD and PAD was 2.25 and 6.97, respectively, after adjusting for other confounding risk factors. In conclusion, high ABI indicated the risk of CVD and PAD in Chinese populations with T2DM.

The ankle brachial index is associated with prognosis in patients with diabetic kidney disease

AimsPeripheral arterial disease (PAD) could be an additional risk factor for the clinical outcomes in different populations. The purpose of this study was to evaluate the influence of PAD on patients with diabetic kidney disease. Methods362 persons with type 2 diabetes were followed-up for a mean 4.8 years grouped by ankle brachial index (ABI) (<0.9 vs. ≧0.9) and albuminuria (with or without). Primary and secondary outcomes were composite events (all-cause mortality, hospitalization for coronary artery disease, stroke, re-vascularization, amputation, and diabetic foot) and all-cause mortality. ResultsInter-group differences in duration of diabetes, glycated hemoglobin, creatinine, and estimated glomerular filtration rate were significant. During the follow-up period, 53 composite events were recorded (14.7%) and 13 (3.5%) individuals died. Subjects with albuminuria plus ABI<0.9 had higher risk of composite events than those with albuminuria but normal ABI (p<0.05). The only trend difference between the two groups was in all-cause mortality. Albuminuria plus ABI <0.9 was associated with risk of composite events (hazard ratio [HR] 4.20, 95% confidence interval [CI] 1.77–9.92, p=0.001) and all-cause mortality (HR 17.77, 95% CI 1.93–162.20, p=0.011). ConclusionsPAD might be an additional risk factor for adverse outcomes in patients with diabetic kidney disease. Further prospective data are required to validate this conclusion.

Lower Extremity Amputation Risk Factors Associated With Elevated Ankle Brachial Indices and Radiographic Arterial Calcification

An elevated ankle brachial index (ABI) resulting from medial artery calcification, or Mönckeberg’s arteriosclerosis, is commonly seen in patients with diabetes mellitus or end-stage renal disease. Recent data have found an association between elevated ABIs and cardiovascular morbidity and mortality. The purpose of the present study was to evaluate the prognostic significance of high ABIs, poorly compressible arteries, and radiographic artery calcification compared with low ABIs in predicting lower extremity amputation and morbidity. A retrospective review was conducted of patients who had undergone a lower extremity amputation from July 1, 2011 to August 31, 2012. A total of 129 patients (140 lower extremity amputations) were categorized into 3 groups: a low ABI (<0.9), a normal ABI (0.9 to 1.3), and a high ABI (>1.3) or poorly compressible arteries. Of the 129 patients, 31 (22.14%), 36 (25.71%), and 73 (52.14%) were in group 1, 2, and 3, respectively. The prevalence of diabetes was greatest in group 2 (p = .016). A high percentage of radiographic arterial calcification was found in all 3 groups (p = .003). Statistically significant differences were also found in groups 1 and 3 for peripheral arterial disease (p < .001), chronic kidney disease (p < .001), coronary artery disease (p = .021), revascularization history (p < .001), and tobacco use (p = .012). A U-shaped relationship between the ABI and comorbidity was found, suggesting an elevated ABI is as equally prognostic as a low index in predicting the need for amputation.

Soluble P-selectin predicts lower extremity peripheral artery disease incidence and change in the ankle brachial index: The Multi-Ethnic Study of Atherosclerosis (MESA)

ObjectiveTo determine the association of circulating P-selectin with prevalent and incident peripheral artery disease (PAD), the ankle brachial index (ABI), and change in the ABI. MethodsThe Multi-Ethnic Study of Atherosclerosis (MESA) is a prospective population-based cohort study including 6814 European descent, African American, Hispanic and Chinese men and women aged 45–84 at baseline. Four clinical exams took place after the baseline exam. After excluding those with ABI>1.4, prevalent and incident PAD were defined as an ABI≤0.90. ABI progression was defined as progression from a normal ABI (0.91–1.4) to abnormal (≤0.90 or >1.4) at a later exam. ResultsIn adjusted models, each SD (13 ng/mL) higher P-selectin was significantly associated with 0.007 lower ABI (95% CI ((−0.011, −0.004)), p < 0.001), and an average change in the ABI of −0.006 ((−0.010, −0.003, p < 0.001). P-selectin was significantly associated with a 1.17-fold greater odds of prevalent PAD ((1.02, 1.33), p = 0.03), and a 30% greater risk of incident PAD ((1.11, 1.53), p = 0.001), as well as progression from a normal ABI to an ABI≤ 0.90 (p = 0.003), but not to an ABI>1.4 (p = 0.96). Addition of P-selectin to models containing traditional PAD risk factors and markers of inflammation/coagulation significantly improved the net reclassification for ABI progression (p = 0.03), but was only marginally significant for incident PAD (p = 0.06). ConclusionsP-selectin is significantly associated with the development of PAD. However, further research is needed in population-based studies to confirm prospective associations of P-selectin with incident PAD and change in the ABI, as well as its potential predictive ability.

Association Between Ankle-Brachial Index and Coronary Lesions Assessed by Coronary Angiography

BackgroundThe ankle-brachial index (ABI) is a simple, non-invasive, and inexpensive method used in the diagnosis of peripheral arterial disease (PAD) and can identify individuals at risk for cardiovascular disease in other arteries of the body, especially the coronary and carotid arteries. The primary objective of this study was to assess whether patients with an ABI < 0.9 have more severe coronary artery disease detected on coronary angiography compared to patients with a normal ABI.MethodsThis is a prospective, analytical, cross-sectional study that was performed from July 1, 2013 to June 31, 2014 that recruited 163 patients (101 men (62%) and 62 women (38%)) according to the inclusion and exclusion criteria. All patients underwent coronary angiography, and then ABI measurements were performed. Pearson’s Chi-square and Student’s t-tests were used to compare variables between groups. The Poisson regression model was used to evaluate whether ABI was an independent predictor of stenoses > 50%.ResultsThe prevalence of ABI < 0.9 was 9.8%. Patients with an ABI < 0.9 had a higher prevalence of stenoses ≥ 50% in the left anterior descendant (LAD) (68.7% vs. 36%, P = 0.02) and left main (8.7% vs. 0.6%, P < 0.001) than those with a normal ABI. On multivariate Poisson regression, an ABI < 0.9 was an independent predictor of stenosis ≥ 50% in the LAD (odds ratio (OR): 2.05 (1.39 - 3.04), P < 0.001).ConclusionsPatients with an ABI < 0.9 had a higher prevalence of stenoses ≥ 50% in the LAD and left main than those with a normal ABI. An abnormal ABI was an independent predictor of lesions ≥ 50% in LAD.

Low Ankle Brachial Index in Acute Ischemic Stroke: Does ApoE Gene Polymorphism Have a Role?

Background: The existence of asymptomatic peripheral arterial disease among patients with acute ischemic stroke has been studied and proved. Low ankle brachial index (ABI) is considered as a marker of atherosclerosis, and its relation to stroke severity was documented in some studies. The effect of different alleles of ApoE gene on acute ischemic stroke presentation in patients with low ABI is not known. Objective: To study the effect of ApoE gene polymorphism on stroke severity, outcome and recurrence in patients with asymptomatic peripheral arterial disease identified by low ABI. Methods: Patients with acute ischemic stroke were screened for the presence of asymp-tomatic peripheral arterial disease by estimating the ABI using a pocket Doppler ultrasound device. Assay of ApoE gene was done using the real-time PCR technique. Results: Low ABI was present in 31% of patients with acute ischemic stroke. There was no significant difference among patients with different ApoE alleles regarding the severity of their symptoms. Also, there was no significant difference among patients with normal ABI and those with abnormal ABI regarding the ApoE gene polymorphism. Conclusion: The current study showed that there was no significant relation between ApoE gene polymorphism and low ABI in ischemic stroke patients who had asymptomatic peripheral arterial disease.

Elevated plasma B-type natriuretic peptide concentration and resistive index, but not decreased aortic distensibility, associate with impaired blood flow at popliteal artery in type 2 diabetic patients.

Blood flow in lower extremity arteries is frequently impaired in diabetic patients even though they have a normal ankle-brachial index (ABI 1.0-1.4). Risk factors contributing to this lower extremity arterial disease have not been fully elucidated. We enrolled 52 type 2 diabetic patients with normal ABI and 30 age-matched nondiabetic subjects consecutively admitted to our hospital. Plasma B-type natriuretic peptide (BNP) concentrations were measured. Distensibility in ascending thoracic and abdominal aortas as well as total flow volume and resistive index at popliteal artery were evaluated by gated magnetic resonance imaging. An automatic device was used to measure ABI and brachial-ankle pulse-wave velocity (baPWV). Diabetic patients showed lower distensibility in ascending thoracic aorta (p<0.001) and total flow volume (p<0.001) and higher baPWV (p<0.001) and resistive index (p=0.005) and similar BNP and distensibility in abdominal aorta compared to nondiabetic subjects. Simple linear regression analyses revealed that distensibility in ascending thoracic (p=0.019) and abdominal (p=0.030) aortas positively as well as baPWV (p=0.020), resistive index (p<0.001) and BNP (p<0.001) negatively correlated with total flow volume. Stepwise multiple regression analysis demonstrated that increased BNP and resistive index were independent risk factors for total flow volume in diabetic patients (r(2)=0.639, p<0.001). These results indicate that increased plasma BNP levels and peripheral vascular resistance, but not decreased aortic distensibility, associate with impaired blood flow in lower extremity arteries in diabetic patients.

Hide and Seek: Does the Toe-brachial Index Allow for Earlier Recognition of Peripheral Arterial Disease in Diabetic Patients?

Arterial calcification may render the ankle-brachial index (ABI) unreliable in diabetic patients. Although guidelines recommend the toe-brachial index (TBI) for patients with falsely elevated ABI arbitrarily defined as an ABI > 1.4, arterial calcification is also common among diabetic patients with an ABI ≤ 1.4. This could result in a "falsely normalized" ABI and under-diagnosis of peripheral arterial disease (PAD). We investigated whether diabetes invalidates the ABI as opposed to the TBI, and if the TBI may therefore be more suitable for detecting PAD in diabetic patients. The difference between ABI and TBI was compared between diabetic and non-diabetic patients with an ABI ≤ 1.4 referred to the vascular laboratory. A Bland-Altman plot was constructed to assess whether ABI-TBI differences were dependent on the magnitude of the measurements. Subgroup analyses were performed for patients with a normal ABI, and for patients with critical ischemia. The population comprised 161 diabetic (252 limbs) and 160 non-diabetic (253 limbs) patients (mean age 67). Median ABIs (0.79 vs. 0.80) were similar, while median TBI was 0.07 higher in diabetics (p=0.024). The ABI-TBI difference in diabetics and non-diabetics was similar (0.32 vs. 0.35; p=.084), and was also similar for patients with a normal ABI. Moreover, ABI-TBI differences in diabetic- and non-diabetic patients overlapped, irrespective of the magnitude of the measurements. Diabetes was not associated with larger differences between ankle and toe pressures (mean difference-0.9mmHg, 95% confidence interval-15 to 13mmHg) among patients with critical ischemia. No evidence was found that the TBI may overcome the potentially invalidated ABI in diabetic patients with an ABI ≤ 1.4. ABI and TBI are strongly associated, and this relationship is not influenced by diabetes. Therefore, the TBI does not allow for earlier detection of ischemia in diabetes.

Peripheral arterial disease and ankle-brachial index abnormalites in young and middle-aged HIV-positive patients in lower Silesia, Poland.

BackgroundPeripheral arterial disease (PAD) is a clinical manifestation of atherosclerosis and mainly refers to elderly patients, having a negative impact on their functionality and quality of life. The findings of previous studies in HIV-infected patients have shown that cardiovascular risk is higher and PAD occurs more frequently than in the general population. There are also contradictory observations. Much less is known about the ankle-brachial index (ABI) value in asymptomatic HIV-infected patients. The aim of this study was to evaluate the prevalence of PAD and ankle-brachial index abnormalities as well as to determine risk factors related to the disease in a group of Polish HIV–positive patients.Methods and FindingsOne hundred and eleven young to middle aged HIV–positive subjects and 40 noninfected subjects were enrolled into the study. Resting ABI measurements were performed and cardiovascular risk was analysed as well. Subgroups were created according to the ABI values: low (PAD), borderline, normal, high and altered ABI. Symptomatic PAD was observed in 2 HIV–positive patients, asymptomatic PAD was not diagnosed. The ABI value is lower and more varied, in 22.5% of the study group altered ABI values were found. Six subjects demonstrated borderline ABI, and 15 high ABI, including >1.4. In the control group no low or very high values were reported. A relation between low ABI and cardiovascular family history and between altered ABI and high–density–lipoprotein cholesterol (HDL–C) level was demonstrated.ConclusionsIn young and middle–aged HIV–positive patients, symptomatic PAD prevalence is comparable to that observed in the overall population. Among asymptomatic patients PAD is not reported. The ABI value in HIV–positive patients is more varied compared to the HIV–negative subjects; the altered ABI shows a strong relation with low HDL–C levels and metabolic syndrome.

Abstract 15730: Ankle-Brachial Index and Physical Function in Community-Based Older Adults: The Atherosclerosis Risk in Communities (ARIC) Study

Background: Lower extremity peripheral artery disease (PAD), commonly defined by an ankle-brachial index (ABI) &lt;0.9, increases mortality risk and also reduces physical function. All prior studies of the impact of PAD on objectively measured physical function have been in restricted populations with known PAD or physical inactivity, leaving uncertainty regarding its impact in the community. Methods: We studied 5,351 ARIC participants (age 71-90 years during 2011-2013) who underwent the assessment of ABI and the Short Physical Performance Battery (SPPB, 0-12 scale), a summary measure of physical function based on three domains (4-meter walk velocity, timed chair stands, and standing balance). Logistic regression models examined the association of ABI with poor physical function (SPPB score &lt;6), adjusting for potential confounders including a history of other cardiovascular diseases. Results: There were 463 participants (8.2%) with ABI &lt;0.9 and 506 participants (9.0%) with ABI ≥1.3, a potential manifestation of PAD reflecting noncompressible pedal arteries. Both ABI &lt;0.9 and ≥1.3 were significantly and independently associated with higher odds of having poor physical function compared to those with a normal ABI (1.1-1.2). The 469 participants (8.8%) with a “borderline” low ABI (0.9-1.0) also demonstrated significantly poor physical function. Low ABI was significantly associated with poor performance in every SPPB domain, whereas none were statistically significant for high ABI. The results were largely consistent among those without a history of stroke or heart failure. Conclusion: In our population of community-dwelling older adults, ~25% had low, borderline low, or high ABI suggestive of PAD and demonstrated poorer physical function compared to those with normal ABI. Since physical function is a key element for independent living in older adults and several therapeutic options for PAD exist, our findings may have broad and important implications.