Normal Ankle-brachial Index Research Articles

Apocynin attenuates angiotensin II-induced vascular smooth muscle cells osteogenic switching via suppressing extracellular signal-regulated kinase 1/2.

Vascular calcification (VC) is a significant risk factor for cardiovascular morbidity and mortality. We recently reported that apocynin had benefits for preventing cardiovascular diseases. However, whether apocynin could attenuate VC is unknown. Here, we investigated the role of apocynin in VC and its underlying mechanisms. 163 participants with high or normal ankle–brachial index (ABI) were enrolled in this study for analyzing the demographic and biochemical data. In vitro, vascular smooth muscle cells (VSMCs) were exposed to calcification medium containing b-glycerophosphate and angiotensin II (Ang II) for 24 hours. The results showed that serum level of Ang II was significantly increased in patients with high ABI (P<0.05). In cultured VSMCs, Ang II significantly exacerbated osteogenic switching. The expression of osteogenic phenotype markers, including bone morphogenetic protein 2 (BMP2), runt-related transcription factor 2 (Runx2) and osteopontin (OPN), were significantly upregulated, whereas contractile markers expression, including alpha smooth muscle actin (a-SMA) and smooth muscle 22 alpha (SM22a) were simultaneously downregulated. However, these effects were greatly attenuated by apocynin. Apocynin enhanced expression of a-SMA by 5.3%, and reduced expression of BMP2, Runx2, OPN by 3.37%, 0.61% and 3.07%, respectively. Furthermore, extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation was upregulated by Ang II, and this effect was also reversed by apocynin. Intriguingly, pretreatment with U0126, an inhibitor of ERK1/2, had similar effects with apocynin. Apocynin may act as a novel molecular candidate to protect against VSMCs osteogenic switching through suppressing ERK1/2 pathway.

Low ankle brachial index is associated with the magnitude of impaired walking endurance in patients with heart failure

BackgroundMeasurement of the ankle brachial index (ABI) is a simple, noninvasive means of diagnosing peripheral arterial disease, and has been shown to be associated with mortality rate. Here, we examined the association between ABI and physical function in patients with heart failure (HF). MethodsThe study population consisted of 524 admitted patients (67.2±13.9years, 343 males) with HF. Blood pressure and the ABI were determined by oscillometry. Prior to hospital discharge, ABI, 6-minute walking distance, walking velocity, handgrip strength, quadriceps isometric strength, and standing balance were determined. The 524 patients were divided according to ABI as follows: ABI≤0.90 (low ABI), ABI 0.91 to 0.99 (borderline ABI), and ABI 1.00 to 1.40 (normal ABI). ResultsLower ABI values were associated with shorter 6-minute walking distance (p trend=0.001), slower walking velocity (p trend=0.023), and poorer standing balance (p trend=0.048). There were no significant associations between ABI and handgrip strength or quadriceps isometric strength. After adjusting for potential confounders, patients with ABI≤0.90 had shorter 6-minute walking distance compared to those with ABI 1.00 to 1.40 (adjusted mean value: 344m vs. 395m, respectively, p<0.001). There were no significant differences in any of the other physical function parameters examined. ConclusionsIn patients with HF, low ABI is associated with the magnitude of impairment in walking endurance.

Type IV Popliteal Arterial Entrapment Associated With an Osteochondroma

A 27-year-old man complaining of a several-month history of right lower extremity coolness was seen by his primary care physician. He works as a farmer and tends his fields on the farm and commonly squats for milking cows. Ten days before presentation, he developed pain in his right foot with walking along with progressively increased coolness in his right leg. On physical examination, he was found to have a cool right lower extremity and no palpable dorsalis pedis or posterior tibial arterial pulses. Doppler examination produced a faint monophasic posterior tibial signal. No sensory deficits were noted. Computed tomography showed occlusion of the anterior tibial artery along with occlusion of the peroneal and posterior tibial arteries. Increased velocities were noted on the duplex ultrasound examination with provocative maneuvers in the tibial vessels. The patient underwent angiography, which demonstrated the occlusion of the anterior tibial, posterior tibial, and peroneal arteries. Catheters were then delivered to the anterior tibial and posterior tibial to allow infusion of tissue plasminogen activator. With repeated angiography, the posterior tibial artery remained occluded, and the anterior tibial artery opened with flow into the dorsalis pedis. The posterior tibial artery remaining occluded in spite of increased dose of tissue plasminogen activator. Further imaging was performed to look for a potential cause of thrombosis. The patient underwent magnetic resonance angiography with active dorsiflexion and plantar flexion to evaluate for potential popliteal entrapment as the patient’s pulse would diminish with plantar flexion. Magnetic resonance angiography demonstrated a pedunculated osteochondroma arising from the right proximal medial tibia. This lesion had significant mass effect on the adjacent medial gastrocnemius and popliteus muscles. With the active maneuvers performed, there was no evidence of compression; however, with the patient’s history, it was suspected that certain activities would cause compartment compression secondary to the osteochondroma. With this pedunculated osteochondroma, the patient was referred to orthopedics for resection. The patient underwent operative exploration with resection of the osteochondroma and release of his popliteus muscle to open the popliteal compartment. Postoperative duplex ultrasound examination demonstrated return of normal ankle-brachial index.

A high normal ankle-brachial index combined with a high pulse wave velocity is associated with cerebral microbleeds.

Arterial stiffness is associated with the pathogenesis of cerebral microbleeds (CMBs). The ankle-brachial index (ABI) is used to predict arterial stiffness. We hypothesized that the increase in ABI with age occurs as a result of increasing arterial stiffness and wave reflection, and is thus associated with target organ damage. The aim of this study was to investigate the relationship between ABI, brachial-ankle pulse wave velocity (baPWV), and CMBs. We recruited 990 cardiovascular disease-free and stroke-free participants [median age 53 (24-86) years, 531 were woman] who underwent brain MRI, ABI, and baPWV at a health checkup. The prevalence of CMBs was 4%. Both ABI (1.14 vs. 1.10) and baPWV (17.29 vs. 14.68 m/s) were higher in participants with CMBs than those without. Cutoff values of ABI and baPWV for the presence of CMBs were 1.12 and 16.07 m/s, respectively. Multivariate logistic regression analysis showed that ABI at least 1.12 [odds ratio (OR) 2.57, 95% confidence interval (CI) 1.30-5.37, P < 0.05] and baPWV at least 16.07 m/s (OR 2.08, 95% CI 1.02-4.38, P < 0.05) were independently associated with CMBs. Moreover, the combination of ABI at least 1.12 and baPWV at least 16.07 m/s was strongly associated with CMBs (OR 5.26, 95% CI 1.93-16.92, P < 0.05). A high normal ABI, combined with a high baPWV, was strongly associated with CMBs in a screened Japanese cohort, suggesting a novel use for ABI as a predictor for target organ damage.

Increased Bone Resorption: A Possible Pathophysiological Link Between Hypovitaminosis D and Peripheral Arterial Disease

Vitamin D deficiency has been associated with the prevalence and severity of peripheral arterial disease (PAD); nevertheless, data on bone turnover in patients with PAD is lacking. The present study investigates a possible relationship between the markers of bone turnover and the presence and severity of PAD. The study examined 143 patients, with a mean±SD age of 75.3±8.5 years (range 50.0-93.0 years), of both sexes, admitted to a department of internal medicine. All patients underwent ankle brachial index (ABI) assessment by Doppler velocimetry. Serum levels of 25(OH) vitamin D and two markers of bone turnover, C-terminal telopeptide of type I collagen (sCTX) and bone isoenzyme of alkaline phosphatase, were measured. The differences between patients with normal ABI and patients with PAD were analyzed. Pearson and Spearman correlation coefficients were calculated and independent predictors were identified through a stepwise linear regression analysis. Odds ratios were calculated with a logistic regression model. Compared with patients with a normal ABI (≥0.90), patients with PAD (ABI<0.90) presented with significantly lower levels of 25(OH) vitamin D (12.2±9.6ng/mL vs. 16.7±8.7ng/mL; p=.006) and a significantly higher concentration of sCTX (1.1±0.7ng/mL vs. 0.6±0.4ng/mL; p<.001). There was a positive correlation between ABI and serum concentration of 25 (OH) vitamin D (r=0.3; p<.001), whereas ABI was inversely correlated with the concentration of sCTX (r=-0.358; p<.001). At logistic regression analysis, age, cigarette smoking, and both vitamin D and sCTX were independent predictors of an ABI<0.90. These results support the hypothesis that hypovitaminosis D and increased bone turnover are risk factors for the presence and severity of PAD. Furthermore, the presence of PAD, even if asymptomatic and diagnosed by a reduced ABI, could identify a population at risk for osteoporosis and osteomalacia.

Prognostic value of ankle brachial index for future incident heart failure in patients without previous heart failure: data from the impressive predictive value of ankle brachial index for clinical long term outcome in patients with cardiovascular disease examined by ABI study.

The ankle brachial index (ABI) is regarded as a predictor of future cardiovascular events. However, the relationship between ABI and incident heart failure (HF) in patients without previous HF is poorly understood. This study aimed to assess the prognostic value of ABI for incident HF in patients without previous HF. The IMPACT-ABI study was a retrospective, single-center, cohort study that enrolled and measured ABI in 3131 patients hospitalized for cardiovascular disease between January 2005 and December 2012. From this cohort, 307 patients were excluded because of previous HF and high (>1.4) ABI. The remaining 2824 patients were stratified into three groups: low ABI (≤0.9), borderline ABI (0.91-0.99), and normal ABI (1.0-1.4). The primary endpoint was hospitalization for HF. Over a mean 4.8-year follow-up, 105 cases of HF occurred. The cumulative incidence of HF was significantly higher in patients with low and borderline ABIs than in those with normal ABI (19.3 vs. 21.0 vs. 10.4%, log rank P<0.001). In multivariate Cox proportional hazard analysis, low ABI and borderline ABI were independent predictors of incident HF [hazard ratio (HR) 3.00; 95% confidence interval (CI) 1.70-5.28; P<0.001 and HR 2.68; 95% CI 1.35-5.34; P=0.005, respectively]. In conclusion, low and borderline ABI were strong predictors for future incident HF in patients without previous HF.

Differences in galectin-3, a biomarker of fibrosis, between participants with peripheral artery disease and participants with normal ankle–brachial index

The aim of this study was to determine if galectin-3 levels were different between participants with peripheral artery disease (PAD) and controls, and to describe its relationship with markers of early atherosclerosis. Sixty participants were recruited into two groups: a PAD group (n=31), ankle-brachial index (ABI) ⩽0.90 and a normal ABI group (n=29), ABI 1.0-1.4. PAD participants were older (68.6 vs 61.8 years, p=0.037), more commonly men (68% vs 38%, p=0.02), and with more cardiovascular risk factors (p<0.001). Galectin-3 was 22% higher in PAD participants (mean±SD: 17.6±4.7 vs 14.4±4.1 ng/mL, p<0.01). The odds ratio for galectin-3 in PAD to be 1 ng/mL higher than the participants with normal ABI was 1.19, after adjusting by age and gender (p=0.014). High-sensitivity C-reactive protein (hs-CRP) and homeostatic model assessment (HOMA) were positively associated with galectin-3 in the age- and gender-adjusted model, while arterial elasticity and microalbuminuria were not. In conclusion, galectin-3 levels were higher in participants with PAD.

Clinical indications for CT angiography in lower extremity trauma

Background: Missed vascular injuries in lower extremity trauma may lead to a preventable lower extremity amputation. CT angiography (CTA) is an accurate and expedient, but costly and potentially harmful, test for vascular injury in lower extremity trauma. Specific physical examination findings and injury patterns may be predictive of detection of a vascular injury by CTA and could guide CTA use in lower extremity trauma. Methods: This was a retrospective review of consecutive trauma patients at an academic level 1 trauma center who underwent CTA of a lower extremity from January 2006 through December 2012. The positive predictive values of injury pattern and physical examination signs for CTA detection of a vascular injury and vascular intervention, adherence to published guidelines for CTA use, and CTA-related adverse events were assessed. Results: Diagnostic CTA studies demonstrated a vascular injury in 55.6%. A vascular intervention followed in 13.9%, while 5.6% of studies led to a contrast-related adverse event. The positive predictive value of a CTA affecting treatment was significantly higher in the presence of high-risk injuries and hard examination findings than in the presence of low-risk injuries and soft examination findings (84.6%, 95% CI [54.6–98.1%] vs. 16.7%, 95% CI [3.6–41.1%]). Palpable pulses and ankle brachial index (ABI)&gt;0.9 led to observational management without complications, regardless of CTA findings or other signs of vascular injury. Conclusions: The utility of CTA is improved by assessing the pretest positive predictive value of vascular injury from injury pattern and physical examination. The Eastern Association for the Surgery of Trauma guidelines may miss some vascular injuries in patients with high-risk injuries and normal ABI. CTA is not indicated in lower extremity trauma when physical examination and injury pattern do not suggest a vascular injury.

Ankle-Brachial Index and Long-Term (10 Years) Survival of Nondiabetic Hemodialysis Patients.

Low (<0.9) and high (>1.4) ankle brachial index (ABI) is associated with a higher cardiovascular (CV) mortality in the general and hemodialysis (HD) population. The aim of our study was to determine the impact of ABI on long-term survival of 52 non-diabetic HD patients. The ABI was determined using an automated, non-invasive waveform analysis device. Patients were divided into three groups: low (<0.9), normal (0.9-1.4) and high (>1.4) ABI. Patients were observed from the date of ABI measurement until their death or ten years. Survival analysis showed higher risk for CV death in HD patients with high ABI compared to normal ABI (log rank test P < 0.027). In Cox regression model adjusted for arterial hypertension, smoking, serum cholesterol and triglycerides, high ABI (P < 0.049) remained a predictor of mortality. The results indicate an association between ABI and long-term survival of non-diabetic HD patients and only high ABI was associated with higher CV mortality.

Peripheral artery disease and blood pressure profile abnormalities in hemodialysis patients.

Patients undergoing chronic hemodialysis (HD) are at increased risk for peripheral artery disease (PAD). Both ankle-brachial index (ABI) and ambulatory blood pressure monitoring (ABPM) in the interdialytic period have been shown to be strong predictors of all-cause mortality. This cross-sectional study investigated the relationship between ABPM profile and ABI in 81 HD patients. ABPM was measured throughout a 44-h midweek interdialytic period. Pre-dialysis ABI was evaluated with a BOSO ABI device. An ABI value <0.9 or ≥1.3 was defined as abnormal. In the whole study group (72% males, mean age 67±14years), there was an increase in BP (p<0.05) and in systolic BP night/day ratio (n/dSR, p=0.01) during the interdialytic period. Patients with abnormal ABI (n=29) more frequently had a positive history for cerebrovascular accident and PAD and higher proBNP values than those with normal ABI (n=52). No difference was detected among ABPM-derived components except for the n/dSR (p=0.02). Patients with abnormal ABI showed a significantly increased n/dSR (p=0.02) and ambulatory arterial stiffness index (AASI) (p=0.006) on the second day compared to the first. Patients with n/dSR >1 during day 2 (n=34) were older, showed significantly higher proBNP and AASI and were more likely to reveal abnormal ABI compared to those with a lower n/dSR (p=0.006). Abnormal ABI in HD patients is associated to changes in interdialytic ABPM pattern, namely higher n/dSR on day 2. These data may indicate the pathophysiological mechanisms underlying the worse outcome observed in HD patients.

Abstract 324: Ankle Brachial Index as a Predictor for Abnormal Cardiovascular Stress Test and Cardiovascular Outcomes

Background: The combination of ankle brachial index (ABI) and other risk stratification tools has been evaluated previously. However baseline ABI in patients admitted for chest pain prior to stress testing to predict increased probability of abnormal stress test and MACE (major cardiovascular adverse events) has not been studied. Methods: Patients (n= 342) admitted for chest pain with normal or unchanged electrocardiogram and negative troponin T who were referred for myocardial perfusion study were enrolled in this prospective observational study and followed for one year. The first part of the study was to assess if an abnormal ABI increases the probability of an abnormal stress test and the second part was to measure one-year outcome for MACE (Angina, MI, CHF, TIA/Stroke and deaths) based on their stress test and ABI results. Multivariable logistic regression modeling is used to interpret the data. Results: In our study population 83% of the patients had Framingham risk score less than 20. Twenty-nine percent of the patients with normal ABI and 40% of the patients with abnormal ABI had abnormal stress test. The difference is statistically insignificant. After adjusting for different variables abnormal ABI was found to have stronger correlation with MACE (Odds ratio 2.9, p 0.01, CI 1.2 - 6.7) as compared to abnormal stress test (Odds ratio 0.92, p 0.84 CI 0.3 - 2.1). Conclusion: In our study cohort an abnormal ABI, irrespective of the stress test results, was an independent predicator of MACE at one year. We can conclude that there is very weak temporal relationship between abnormal ABI and abnormal stress test in low risk population and asymptomatic peripheral vascular disease is a strong independent predictor of MACE, even in this low risk population. We can also conclude that ABI during stress testing can be used for risk stratification. Future studies may need more power in this low risk population.

Upper-to-lower-limb Collateral Circulation in a Patient with Aortic Coarctation

A 35-year-old male was hospitalized with a pulsatile mass in the left shoulder region. He had a history of uncontrolled hypertension for more than 5 years. A computed tomography angiogram revealed a giant left subclavian artery aneurysm and also an aortic coarctation (A). Interestingly, hypoplasia of the right common/external iliac arteries was present, and significant collateral circulation was noted between the right subclavian artery and the distal right external iliac artery, restoring blood flow to the right lower extremity (B). This could explain why this patient had a normal ankle brachial index and did not suffer from intermittent claudication.

Borderline ankle-brachial index is associated with poor short-term clinical outcome after coronary artery intervention

ObjectiveTo evaluate the association between borderline ankle-brachial index (ABI) and clinical outcome in patients who underwent percutaneous coronary intervention (PCI). MethodsFrom August 2009 to August 2012, ABI was measured in 1291 patients who underwent PCI. Patients with borderline ABI were compared with those who had normal ABI. The primary outcome was major adverse cardiac and cerebrovascular event (MACCE), defined as a composite of all-cause death, myocardial infarction, stroke, and repeat revascularization. ResultsOf the 1291 patients, 1154 (82%) had normal ABI and 89 (7%) had borderline ABI. The median overall follow-up duration was 19 (interquartile range 13–26) months. After adjustment with IPTW, the incidence of stroke (HR, 6.28; CI 95%, 1.95–20.19; P < 0.01) and MACCE (HR, 2.54; CI 95%, 1.40–4.62; P < 0.01) were higher in the borderline ABI group. In a propensity score-matched population, the incidence of stroke (HR, 4.68; CI 95%, 1.18–18.52; p = 0.03) and MACCE (HR, 2.12; CI 95%, 1.09–4.11; P = 0.03) were still significantly higher. ConclusionThe presence of borderline ABI was associated with worse clinical outcome and increased stroke rate compared with normal ABI during the short-term follow-up period in patients who underwent coronary intervention.

The Ankle Brachial Index Exhibits Better Association of Cardiovascular Prognosis Than Non–High-Density Lipoprotein Cholesterol in Type 2 Diabetes

ObjectiveThe association between ankle brachial index (ABI) and outcomes in diabetic subjects is controversial. The purpose of this study was to evaluate whether the ABI is more strongly associated with cardiovascular outcomes comparing with non–high-density lipoprotein cholesterol (non–HDL-c). Research Design and MethodsA total of 452 type 2 diabetic subjects followed up for a mean of 5.8 years were grouped by ABI (<0.9 versus ≥0.9) and non–HDL-c (<100mg/dL versus ≥100mg/dL). Primary outcomes were composite events including all-cause mortality, hospitalization for coronary artery disease, stroke, revascularization, amputation and diabetic foot, and the secondary end point was all-cause mortality. ResultsIntergroup differences in percentage of men, duration of diabetes, hemoglobin A1c, total cholesterol, low-density lipoprotein cholesterol, triglycerides and estimated glomerular filtration rate were significant. A total of 64 composite events and 17 deaths were recorded. A higher number of composite events occurred in the group with abnormal ABI but optimal non–HDL-c than in those with suboptimal non–HDL-c but normal ABI (29% versus 11%, P < 0.05). A similar trend was observed in all-cause mortality (11% versus 1%, P < 0.05). The ABI was the dominant risk factor for both end points after adjusting other factors (for composite events, hazard ratio = 0.02, 95% CI: 0.00-0.10, P < 0.001 and for all-cause mortality, hazard ratio = 0.01, 95% CI: 0.00-0.28, P = 0.006). ConclusionsThe ABI was more strongly associated with outcomes in diabetes than non–HDL-c. The ABI should be routinely screened in diabetes even without symptom.

Role of Coronary Artery Calcium Score of Zero and Other Negative Risk Markers for Cardiovascular Disease: The Multi-Ethnic Study of Atherosclerosis (MESA).

Limited attention has been paid to negative cardiovascular disease (CVD) risk markers despite their potential to improve medical decision making. We compared 13 negative risk markers using diagnostic likelihood ratios (DLRs), which model the change in risk for an individual after the result of an additional test. We examined 6814 participants from the Multi-Ethnic Study of Atherosclerosis. Coronary artery calcium score of 0, carotid intima-media thickness <25th percentile, absence of carotid plaque, brachial flow-mediated dilation >5% change, ankle-brachial index >0.9 and <1.3, high-sensitivity C-reactive protein <2 mg/L, homocysteine <10 µmol/L, N-terminal pro-brain natriuretic peptide <100 pg/mL, no microalbuminuria, no family history of coronary heart disease (any/premature), absence of metabolic syndrome, and healthy lifestyle were compared for all and hard coronary heart disease and all CVD events over the 10-year follow-up. Models were adjusted for traditional CVD risk factors. Among all negative risk markers, coronary artery calcium score of 0 was the strongest, with an adjusted mean DLR of 0.41 (SD, 0.12) for all coronary heart disease and 0.54 (SD, 0.12) for CVD, followed by carotid intima-media thickness <25th percentile (DLR, 0.65 [SD, 0.04] and 0.75 [SD, 0.04], respectively). High-sensitivity C-reactive protein <2 mg/L and normal ankle-brachial index had DLRs >0.80. Among clinical features, absence of any family history of coronary heart disease was the strongest (DLRs, 0.76 [SD, 0.07] and 0.81 [SD, 0.06], respectively). Net reclassification improvement analyses yielded similar findings, with coronary artery calcium score of 0 resulting in the largest, most accurate downward risk reclassification. Negative results of atherosclerosis-imaging tests, particularly coronary artery calcium score of 0, resulted in the greatest downward shift in estimated CVD risk. These results may help guide discussions on the identification of individuals less likely to receive net benefit from lifelong preventive pharmacotherapy.

Relationship between percentage of mean arterial pressure at the ankle and mortality in participants with normal ankle-brachial index: an observational study

ObjectivesPeripheral arterial disease (PAD) is associated with all-cause mortality. Ankle-brachial index (ABI) is the most widely used tool for detecting PAD, but can yield false-negative results in patients with non-compressible...

Pulse Pressure and Upstroke Time Are Useful Parameters for the Diagnosis of Peripheral Artery Disease in Patients With Normal Ankle Brachial Index

BackgroundSome peripheral artery disease (PAD) patients have normal ankle brachial index (ABI) (0.9 - 1.4), although ABI is a useful parameter for the diagnosis of PAD. We investigated whether other parameters of ABI report sheet are useful to detect these patients.MethodsWe initially enrolled 3,912 patients (7,824 limbs) who underwent ABI for the first time. Subjects who have normal ABI were divided into the PAD group (n = 136) and the non-PAD group (n = 240) by lower extremity ultrasonography. We investigated blood pressures (BP) (systolic (SBP), diastolic (DBP), mean (mBP) and pulse pressure (PP)), heart rate, upstroke time (UT), and %mean arterial pressure (%MAP).ResultsSBP, mBP, PP, UT, and %MAP in the PAD group were significantly higher. A multivariate analysis showed that mBP, DBP, PP, UT and %MAP were independently associated with the presence of PAD (mBP: odds ratio (OR) 2.30, 95% confidence interval (CI) 1.22 - 4.37, P = 0.010; DBP: OR 0.52, 95% CI 0.28 - 0.97, P = 0.039; PP: OR 1.30, 95% CI 0.69 - 2.46, P = 0.041; UT: OR 3.40, 95% CI 2.03 - 5.83, P < 0.001; %MAP: OR 1.77, 95% CI 1.05 - 2.98, P = 0.031). Maximal area under the curve (AUC) of BPs for associating PAD was PP. The cut-off value of PP was 53.0 mm Hg (sensitivity 0.500, specificity 0.721, AUC 0.628, 95% CI 0.569 - 0.687).ConclusionsThe present study demonstrated that BPs are associated with PAD in patients with normal ABI. The measurement of BPs could provide additional information for the diagnosis of PAD.

Pattern of ankle brachial index among adults in Sagamu South-West Nigeria

Background: The ankle-brachial index (ABI) is a ratio of Doppler recorded ankle and brachial systolic blood pressure. ABI value of Objectives: To determine the pattern of ABI, the prevalence of PAD, and the risk factors for low ABI. Subjects and Methods: Four hundred subjects aged 50 years and above were selected by systematic random sampling. Their demographic data and cardiovascular risk factors were assessed, and their ABI was measured. ABI value of ≤0.9 was taken as low ABI indicating PAD while a value >1.3 was taken as high ABI indicating arterial calcification. Results: Two hundred and eighty-eight (72.0%) of the participants had normal ABI, 99 (24.8%) had low ABI indicating PAD, and 13 (3.3%) had high ABI. The prevalence of low ABI increased from 4.9% between 50 and 59 years to 25.3% and 58.7% between 60 and 69 and ≥70 years, respectively. The risk factors for low ABI were age (P = 0.00), history of hypertension (P = 0.03), and diabetes mellitus (DM) (P = 0.00). Conclusion: 24.8% of the participants had low ABI indicating PAD. The prevalence of PAD increases by 5–10 folds after the fifth decade of life. Low ABI was associated with advancing age, DM, and hypertension.

CORRIGENDUM: Change in Ankle-Brachial Index Over Time in a Screened Japanese Cohort - The Okinawa Peripheral Arterial Disease Study.

BACKGROUND The temporal change in ankle-brachial index (ABI) in the general population, especially in those aged <40 years, remains unclear. METHODS AND RESULTS ABIs of 23,673 individuals were measured in 1-day health checkups between 2003 and 2010. Among them, 1,117 participants aged 28-76 years (mean 53±9 years) whose ABI was measured at least twice within an interval of ≥4 years (mean: 4.9 years) were selected for this study. Baseline ABI was the lowest at age <40 years and increased with age. ABI significantly increased in participants aged <40 and 40-49 years, but not in participants aged 50-59 and ≥60 years. ABI increased in participants with borderline-low baseline ABI (0.9<ABI<1.0, 0.09; P<0.001) and normal baseline ABI (1.0≤ABI<1.2, 0.006; P=0.017). ABI decreased in participants with high-normal baseline ABI (1.2≤ABI<1.4, -0.04; P<0.001). Stepwise multivariate analysis revealed that ABI change was independently associated with baseline ABI (β=-0.566), height (β=0.162), body mass index (β=0.093), and sex (women, β=-0.08). CONCLUSIONS ABI was lowest at age <40 years and increased with age. In participants aged <50 years, ABI significantly increased over the mean observation period of 4.9 years. (Circ J 2016; 80: 2004-2009).

Increased plasma serotonin metabolite 5-hydroxyindole acetic acid concentrations are associated with impaired systolic and late diastolic forward flows during cardiac cycle and elevated resistive index at popliteal artery and renal insufficiency in type 2 diabetic patients with microalbuminuria.

Although lower extremity arterial disease is frequently accompanied by diabetes mellitus, the association of circulating biomarkers with flow components during the cardiac cycle in lower-leg arteries has yet to be fully elucidated. We enrolled 165 type 2 diabetic patients with normal ankle-brachial index (ABI 1.0-1.4), comprising 106 normoalbuminuric and 59 microalbuminuric patients, and 40 age-matched nondiabetic subjects consecutively admitted to our hospital. Serum high sensitivity C-reactive protein (hsCRP) level and plasma von Willebrand factor ristocetin cofactor activity (VWF) and vasoconstrictor serotonin metabolite 5-hydroxyindole acetic acid (5-HIAA) concentrations were measured. An automatic device was used to measure ABI and brachial-ankle pulse wave velocity (baPWV). Flow components during the cardiac cycle, total flow volume, and resistive index at popliteal artery were evaluated using gated magnetic resonance imaging. Although estimated glomerular filtration rate (eGFR), early diastolic flow reversal, heart rate, and ABI were similar between the groups, diabetic patients had higher log hsCRP (p<0.001), VWF (p<0.001), 5-HIAA (p=0.002), resistive index (p<0.001) and baPWV (p<0.001) and lower systolic (p=0.026) and late diastolic (p<0.001) forward flows and total flow volume (p<0.001) than nondiabetic subjects. Multivariate analyses demonstrated that 5-HIAA in microalbuminuric patients showed higher associations with systolic and late diastolic forward flows during the cardiac cycle, total flow volume and resistive index at popliteal artery, and eGFR compared to normoalbuminuric patients. In microalbuminuric patients, 5-HIAA was a significant independent determinant among these factors. Thus, increased plasma 5-HIAA levels are involved in the pathogenesis of impaired blood flow in lower extremities and renal insufficiency in diabetic patients with microalbuminuria.