Pulse Waves in the Lower Extremities as a Diagnostic Tool of Peripheral Arterial Disease and Predictor of Mortality in Elderly Chinese

Novel Peripheral Perfusion Dynamics Indices for Detecting and Grading Arterial Stenosis

PURPOSE

Peripheral artery disease causes severe morbidity, especially in diabetics and the elderly. There is a need for accurate noninvasive detection of peripheral arterial stenosis. The study has tested the hypothesis that arterial stenosis and the associated adaptation of the downstream circulation yield characteristic changes in the leg perfusion dynamics that enable early diagnosis, utilizing impedance plethysmography.

METHODS

The arterial perfusion dynamic was derived from impedance plethysmography (IPG). Two degrees of arterial stenosis were emulated by inflating a blood-pressure cuff around the thigh to 45 and 90 mmHg, in healthy volunteers (n = 30). IPG signals were acquired continuously throughout the experiment. Ankle and brachial blood pressures were measured at the beginning of each experiment and at the end of each emulated stenosis phase.

RESULTS

Thigh compressions did not affect the pulse-transit time, but prolonged the time to the peak perfusion wave. Segmentation of the perfusion upstroke into two phases, at the time point of maximum acceleration (MAT), revealed that arterial compression prolonged only the initial slow phase duration (SPd). The MAT and SPd were proportional to the emulated stenosis severity and detected the arterial stenosis with high sensitivity (> 93%) and specificity (100%). The SPd increased from 46.4 ± 21.2 ms at baseline to 75.4 ± 38.5 ms and 145 ± 39 ms under 45 mmHg and 90 mmHg compressions (p < 0.001), without affecting the pulse-transit time.

CONCLUSIONS

The novel method and indices can identify and grade the emulated arterial stenosis with high accuracy and may assist in differentiating between focal arterial stenosis and widespread arterial hardening.

Machine Learning-Based Peripheral Artery Disease Identification Using Laboratory-Based Gait Data

Peripheral artery disease (PAD) manifests from atherosclerosis, which limits blood flow to the legs and causes changes in muscle structure and function, and in gait performance. PAD is underdiagnosed, which delays treatment and worsens clinical outcomes. To overcome this challenge, the purpose of this study is to develop machine learning (ML) models that distinguish individuals with and without PAD. This is the first step to using ML to identify those with PAD risk early. We built ML models based on previously acquired overground walking biomechanics data from patients with PAD and healthy controls. Gait signatures were characterized using ankle, knee, and hip joint angles, torques, and powers, as well as ground reaction forces (GRF). ML was able to classify those with and without PAD using Neural Networks or Random Forest algorithms with 89% accuracy (0.64 Matthew's Correlation Coefficient) using all laboratory-based gait variables. Moreover, models using only GRF variables provided up to 87% accuracy (0.64 Matthew's Correlation Coefficient). These results indicate that ML models can classify those with and without PAD using gait signatures with acceptable performance. Results also show that an ML gait signature model that uses GRF features delivers the most informative data for PAD classification.

Evaluation of the role of combining inter-arm systolic pressure difference and derivatives of pulse volume recording in detecting subclavian artery stenosis

Background

Subclavian artery stenosis (SAS) is a peripheral arterial disease of asymptomatic appearance and disastrous consequences. The traditional screening method remains unsatisfactory.

Objective

The study aimed to assess the diagnostic performances of inter-arm systolic pressure difference (IASBPD), derivatives of pulse volume recording (PVR), and their combination in detecting subclavian artery stenosis.

Materials and methods

The present study was a retrospective analysis of clinical data from inpatients suspected of supra-arch artery stenosis in Fuwai hospital during 1 year, who underwent selective arterial angiographies. We obtained simultaneous blood pressure measurements on four limbs and pulse waves for calculating IASBPD and PVR derivatives prior to the angiographies. We utilized the receiver operating characteristic curve (ROC) to calculate the optimal cut-off value of IASBPD, upstroke time (UT), and upstroke time per cardiac cycle (UTCC) for detecting SAS. Moreover, we compared the sensitivity and specificity of IASBPD, UT, UTCC, and their combinations for diagnosing SAS (Clinical trial number: NCT03521739).

Results

We consecutively enrolled 320 eligible patients. Based on SAS’s definition of stenosis above 50%, the area under the curve of IASBPD, UT, and UTCC were 0.84, 0.76, and 0.80 (P < 0.001). And their corresponding cut-off points were 9 mmHg, 202 milliseconds, and 23.2%. The sensitivity and specificity of IASBPD ≥ 9 mmHg were 57.0 and 94.1%. UT ≥ 202 ms and UTCC ≥ 23.2% yielded similar sensitivity (72.6 vs. 72.6%, P > 0.05), but UTCC had higher specificity (81.1 vs. 72.4%, P < 0.05). The sensitivity of the combination of IASBPD and UT (85.2%) or UTCC (78.5%) was significantly higher than IASBPD alone (57%, P < 0.05). The specificity of either combination decreased to 67.6 and 76.8% (P < 0.05).

Conclusions

This present study showed that the combinations of IASBPD and PVR-derived parameters promoted diagnostic sensitivity and preserved adequate specificity than those alone for detecting SAS.

Serum triglycerides concentration in relation to total and cardiovascular mortality in an elderly Chinese population

OBJECTIVE

To investigate serum triglycerides in relation to all-cause, cardiovascular, and non-cardiovascular mortality in an elderly Chinese population.

METHODS

The study participants (n = 3565) were elderly (≥ 60 years) community dwellers living in a suburban town of Shanghai. Hypertriglyceridemia was defined as a serum triglycerides concentration ≥ 2.30 mmol/L (definite) and ≥ 1.70 mmol/L (borderline), respectively.

RESULTS

The prevalence of definite and borderline hypertriglyceridemia at baseline was 7.5% and 29.5%, respectively. It was higher in women (n = 1982, 9.0% and 33.8%, respectively) than men (n = 1583, 6.2% and 27.9%, respectively), in obese and overweight participants (n = 1566, 10.5% and 36.4%, respectively) than normal weight participants (n = 1999, 5.6% and 27.1%, respectively), and in diabetic participants (n = 177, 11.9% and 39.0%, respectively) than non-diabetic participants (n = 3388, 7.5% and 30.8%, respectively). During a median of 7.9 years follow-up, all-cause, cardiovascular and non-cardiovascular deaths occurred in 529, 216 and 313 participants, respectively. In analyses according to the quintile distributions of serum triglycerides concentration, the sex- and age-standardized mortality rate was lowest in the middle quintile for all-cause, cardiovascular and non-cardiovascular mortality (18.6, 7.8 and 11.9 per 1000 person-years, respectively, versus 21.5, 10.5 and 12.7 per 1000 person-years, respectively, in the two lower quintiles and 21.7, 9.5 and 14.0 per 1000 person-years, respectively, in the two higher quintiles). The fully adjusted hazard ratios (95% CI) for the middle quintile versus the combined two lower with two higher quintiles were 0.85 (95% CI: 0.67-1.07, P = 0.17), 0.81 (95% CI: 0.54-1.19, P = 0.28) and 0.87 (95% CI: 0.64-1.17, P = 0.35) for all-cause, cardiovascular and non-cardiovascular mortality, respectively.

CONCLUSIONS

Our study showed high prevalence of hypertriglyceridemia, especially when defined as borderline and in obese and overweight participants, and mildly but non-significantly elevated risks of cardiovascular mortality relative to the middle level of serum triglycerides.

Alcohol consumption in relation to cardiovascular and non-cardiovascular mortality in an elderly male Chinese population

Background

We investigated the association of alcohol consumption with cardiovascular and non-cardiovascular mortality in elderly Chinese men.

Methods

Our participants were recruited from residents living in a suburban town of Shanghai (≥60 years of age, n = 1702). Alcohol intake was classified as non-drinkers, past drinkers (stopped drinking for ≥12 months), and current light-to-moderate (1 to 299 g/week) and heavy drinkers (≥300 g/week). Alcoholic beverages were classified as beer/wine, rice aperitif and liquor/mix drinking.

Results

During 5.9 years (median) of follow-up, all-cause, cardiovascular and non-cardiovascular deaths occurred in 211, 98 and 113 participants, respectively. The corresponding incidence rates were 23.6/1000, 10.9/1000 and 12.6/1000 person-years, respectively. Both before and after adjustment for confounding factors, compared with non-drinkers (n = 843), past drinkers (n = 241), but not the current light-to-moderate (n = 241) or heavy drinkers (n = 377), had a higher risk of all-cause (adjusted hazard ratio [HR] 1.90, 95% confidence interval [CI] 1.35–2.68, P = 0.0003) and non-cardiovascular mortality (HR 2.46, 95% CI 1.55–3.91, P = 0.0001). Similar trends were observed for cardiovascular mortality (HR 1.44, 95% CI 0.85–2.44, P = 0.18). In similar unadjusted and adjusted analyses, compared with the current beer/wine drinkers (n = 203), liquor/mix drinkers (n = 142), but not aperitif drinkers (n = 273), had a significantly higher risk of all-cause (HR 3.07, 95% CI 1.39–6.79, P = 0.006), and cardiovascular mortality (HR 10.49, 95% CI 2.00–55.22, P = 0.006). Similar trends were observed for non-cardiovascular mortality (HR 1.94, 95% CI 0.73–5.16, P = 0.18).

Conclusions

Our study showed risks of mortality associated with past drinking and liquor drinking in the elderly Chinese men.

Carotid-Femoral Pulse Transit Time Variability Predicted Mortality and Improved Risk Stratification in the Elderly

[Figure: see text].

Racial and Ethnic Disparities in Peripheral Artery Disease

Peripheral artery disease is an obstructive, atherosclerotic disease of the lower extremities causing significant morbidity and mortality. Black Americans are disproportionately affected by this disease while they are also less likely to be diagnosed and promptly treated. The consequences of this disparity can be grim as Black Americans bear the burden of lower extremity amputation resulting from severe peripheral artery disease. The risk factors of peripheral artery disease and how they differentially affect certain groups are discussed in addition to a review of pharmacological and nonpharmacological treatment modalities. The purpose of this review is to highlight health care inequities and provide a review and resource of available recommendations for clinical management of all patients with peripheral artery disease.

Physician initiated, prospective, non-randomized Multi-center trial, Investigating the safety and Efficacy of the TReatment with the LuminorTM Drug Coated Balloon and the AngioliteTM Drug Eluting Stent of IVascular in TASC C and D Tibial Occlusive disease iN patients with critical limb ischemia: 12-month results

BACKGROUND

The aim of MERLION (NCT04073121) was to evaluate the outcomes of the mono or combination therapy of the iVascular LuminorTM drug coated balloon (DCB) and AngioliteTM drug eluting stent for treatment of TASC II C/D tibial occlusive lesions in Asian patients presenting with chronic limb threatening ischemia (CLTI) from Singapore.

METHODS

MERLION was a prospective, non-randomized, single arm, observational, multicenter clinical study. Complication-free survival at one month was the safety endpoint. Immediate technical success, 12-month primary vessel patency, limb salvage, freedom from target lesion revascularization (TLR) and amputation free survival (AFS) were the efficacy endpoints of interest.

RESULTS

50 patients were included. There were 32 males (64% males; mean age 66.4±8.9 years). Majority were Rutherford 5 severity (41/50; 82%). Co-morbidities included diabetes mellitus (47/50; 94.0%), end-stage renal failure (25/50; 50.0%), and hypertension (44/50; 88%). 66 atherosclerotic lesions were treated (47 de novo and 19 restenotic; 60.6% TASC C and 39.4% TASC D). Mean lesion length treated was 13.7±9.5cm. There was 100% technical success. There were 3/66 (4.5%) bailout stenting for severe flow limiting dissections. 12-month primary tibial patency was 34/49 (69.4%) and freedom from TLR was 40/49 (81.5%). AFS was 74.0% (37/50). At 12 months, mean Rutherford scores improved from 100% (Rutherford score>3) at baseline to 31% at 12 months (p<0.05) and wound healing rate was 65.7%.

CONCLUSIONS

The iVascular LuminorTM DCB is safe and efficacious in treating highly complex infra-popliteal atherosclerotic lesions in an otherwise challenging frail population of CLTI patients from Singapore.

Similarities and differences in peripheral artery disease between China and Western countries

OBJECTIVE

Peripheral artery disease (PAD) affects more than 200 million people worldwide, among whom more than two-thirds reside in low- and middle-income countries. China, as the largest low- and middle-income country, faces a challenge from the burden of PAD as the country undergoes economic expansion. We compared the patterns of PAD between China and Western countries to determine if there are differences in risk factors, awareness, or treatment of PAD.

METHODS

Literature searches were performed both in English databases and Chinese databases covering January 1, 1995, to March 1, 2020. Both landmark and high-quality articles were evaluated.

RESULTS

The prevalence of PAD in high-income countries increases linearly with age, whereas PAD increases slowly until the middle 60s and exponentially thereafter in China. In contrast with Western countries, the prevalence of PAD in China is reported to be higher in women than in men. There is a higher prevalence of risk factors in China, but the rates of awareness and treatment of these risk factors are low.

CONCLUSIONS

The lack of awareness and lower rates of treatment and control of PAD and its risk factors in China may be underlying the higher prevalence of PAD in women than in men as well as the steep increase in PAD after the middle 60s. In all countries, more attention should be paid to the planning and implementation of preventative strategies and clinical services. The societal and economic effects of PAD are considerable and ongoing studies are needed to help curtail the burden of this disease.

Radiation effects on atherosclerosis in atomic bomb survivors: a cross-sectional study using structural equation modeling

Past reports indicated that total-body irradiation at low to moderate doses could be responsible for cardiovascular disease risks, but the mechanism remains unclear. The purpose of this study was to investigate the association between radiation exposure and atherosclerosis, an underlying pathology of cardiovascular diseases, in the Japanese atomic bomb survivors. We performed a cross-sectional study measuring 14 clinical-physiological atherosclerosis indicators during clinical exams from 2010 to 2014 in 3274 participants of the Adult Health Study cohort. Multivariable analyses were performed by using a structural equation model with latent factors representing underlying atherosclerotic pathologies: (1) arterial stiffness, (2) calcification, and (3) plaque　as measured with indicators chosen a priori on the basis of clinical-physiological knowledge. Radiation was linearly associated with calcification (standardized coefficient per Gy 0.15, 95 % confidence interval: CI [0.070, 0.23]) and plaque (0.11, 95 % CI [0.029, 0.20]), small associations that were comparable to about 2 years of aging per Gy of radiation exposure, but not with arterial stiffness (0.036, 95 % CI [− 0.025, 0.095]). The model fitted better and had narrower confidence intervals than separate ordinary regression models explaining individual indicators independently. The associations were less evident when the dose range was restricted to a maximum of 2 or 1 Gy. By combining individual clinical-physiological indicators that are correlated because of common, underlying atherosclerotic pathologies, we found a small, but significant association of radiation with atherosclerosis.

Usefulness of Upstroke Time per Cardiac Cycle for Cardiovascular and All-Cause Mortality Prediction in Patients with Normal Ankle-Brachial Index

AIM

Abnormal ankle-brachial index (ABI) is regarded as peripheral artery disease and can be used to predict cardiovascular (CV) outcomes. However, the usefulness of ABI for the prediction of CV outcome in patients with normal ABI is limited. Upstroke time per cardiac cycle (UTCC) is recently reported to be associated with mortality in patients with acute myocardial infarction and the elderly. Therefore, we aimed to evaluate UTCC, left ventricular ejection fraction (LVEF), brachial-ankle pulse wave velocity (baPWV), and ABI for the prediction of mortality in patients with normal ABI.

METHODS

Patients arranged for echocardiographic examinations were enrolled, and 1076 patients with normal ABI were included. ABI, baPWV, and UTCC were measured by an ABI-form device.

RESULTS

The median follow-up to mortality was 95 months. There were 88 CV and 244 all-cause deaths. After multivariate analysis, UTCC was associated with increased CV and all-cause mortality (P ≤ 0.004). Age, diabetes, heart failure, left ventricular hypertrophy, baPWV, and LVEF were also independent predictors of CV and all-cause mortality, but ABI was not. Furthermore, UTCC had a better additive predictive value than ABI, baPWV, and LVEF for CV mortality (P ≤ 0.012). It also had a better additive predictive value than ABI and LVEF for all-cause mortality (P ≤ 0.013).

CONCLUSIONS

UTCC is an independent predictor for CV and all-cause mortality in patients with normal ABI. It also has a better additive predictive value of CV and all-cause mortality than ABI and LVEF. Therefore, UTCC is a simple, novel, and useful parameter for identifying high-risk patients with normal ABI.

Digital Predictors of Morbidity, Hospitalization, and Mortality Among Older Adults: A Systematic Review and Meta-Analysis

The widespread adoption of digital health technologies such as smartphone-based mobile applications, wearable activity trackers and Internet of Things systems has rapidly enabled new opportunities for predictive health monitoring. Leveraging digital health tools to track parameters relevant to human health is particularly important for the older segments of the population as old age is associated with multimorbidity and higher care needs. In order to assess the potential of these digital health technologies to improve health outcomes, it is paramount to investigate which digitally measurable parameters can effectively improve health outcomes among the elderly population. Currently, there is a lack of systematic evidence on this topic due to the inherent heterogeneity of the digital health domain and the lack of clinical validation of both novel prototypes and marketed devices. For this reason, the aim of the current study is to synthesize and systematically analyse which digitally measurable data may be effectively collected through digital health devices to improve health outcomes for older people. Using a modified PICO process and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) framework, we provide the results of a systematic review and subsequent meta-analysis of digitally measurable predictors of morbidity, hospitalization, and mortality among older adults aged 65 or older. These findings can inform both technology developers and clinicians involved in the design, development and clinical implementation of digital health technologies for elderly citizens.

Upstroke Time as a Novel Predictor of Mortality in Patients with Chronic Kidney Disease

Upstroke time (UT), measured from the foot-to-peak peripheral pulse wave, is a merged parameter used to assess arterial stiffness and target vascular injuries. In this study, we aimed to investigate UT for the prediction of cardiovascular and all-cause mortality in patients with chronic kidney disease (CKD). This longitudinal study enrolled 472 patients with CKD. Blood pressure, brachial pulse wave velocity (baPWV), and UT were automatically measured by a Colin VP-1000 instrument. During a median follow-up of 91 months, 73 cardiovascular and 183 all-cause mortality instances were recorded. Multivariable Cox analyses indicated that UT was significantly associated with cardiovascular mortality (hazard ratio (HR) = 1.010, p = 0.007) and all-cause mortality (HR = 1.009, p < 0.001). The addition of UT into the clinical models including traditional risk factors and baPWV further increased the value in predicting cardiovascular and all-cause mortality (both p < 0.001). In the Kaplan–Meier analyses, UT ≥ 180 ms could predict cardiovascular and all-cause mortality (both log-rank p < 0.001). Our study found that UT was a useful parameter in predicting cardiovascular and all-cause mortality in CKD patients. Additional consideration of the UT might provide an extra benefit in predicting cardiovascular and all-cause mortality beyond the traditional risk factors and baPWV.

Upstroke Time Per Cardiac Cycle as A Novel Parameter for Mortality Prediction in Patients with Acute Myocardial Infarction

Background: Acute myocardial infarction (AMI) is one of the leading causes of death in the world. How to simply predict mortality for AMI patients is important because the appropriate treatment should be done for the patients with higher risk. Recently, a novel parameter of upstroke time per cardiac cycle (UTCC) in lower extremities was reported to be a good predictor of peripheral artery disease and mortality in elderly. However, there was no literature discussing the usefulness of UTCC for prediction of cardiovascular (CV) and overall mortality in AMI patients. Methods: 184 AMI patients admitted to the cardiac care unit were enrolled. Ankle-brachial index (ABI) and UTCC were measured by an ABI-form device in the same day of admission. Results: The median follow-up to mortality was 71 months. There were 36 CV and 124 overall mortality. Higher UTCC was associated with increased CV and overall mortality after multivariable analysis (P = 0.033 and P < 0.001, respectively). However, ABI was only associated with CV mortality and overall mortality in the univariable analysis but became insignificant after the multivariable analysis. In addition, after adding UTCC into a basic model including important clinical parameters, left ventricular ejection fraction, Charlson comorbidity index, and ABI, we found the basic model + UTCC had a better predictive value for overall mortality than the basic model itself (P < 0.001). Conclusions: Our study is the first one to evaluate the usefulness of UTCC in AMI patients for prediction of long-term mortality. Our study showed UTCC was an independent predictor of long-term CV and overall mortality and had an additive predictive value for overall mortality beyond conventional parameters. Therefore, screening AMI patients by UTCC might help physicians to identify the high-risk group with increased mortality.

The HOPE Asia Network activity for "zero" cardiovascular events in Asia: Overview 2020

The impact of hypertension-related cardiovascular disease and target organ damage, and therefore the benefits of blood pressure (BP) control, is greater in Asian than in Western countries. Asia-specific features of hypertension and its effective management are important and active areas of research. The Hypertension Cardiovascular Outcome Prevention and Evidence in Asia (HOPE Asia) Network was formed in 2016 and is now a member of the World Hypertension League. The main goal of the HOPE Asia Network is to improve the management of hypertension and organ protection toward achieving "zero" cardiovascular events in Asia. Considerable work has already been done on the journey to achieving this goal. We have shown that BP control status in Asia differs between countries, and even between regions within the same country. Several expert panel consensus recommendations and clinical guidance papers are available to support the use of home and ambulatory BP monitoring in the region. In addition, the AsiaBP@Home study prospectively investigated home BP control status across 15 specialist centers using the same validated device and measurement schedule. We have also proposed the concept of systemic hemodynamic atherothrombotic syndrome (SHATS), a vicious cycle of BP variability and vascular disease on cardiovascular events and organ damage, and suggested a SHATS score for risk stratification for clinical practice. This special issue of the journal collates Asia-specific resources and data, contributing to advances in hypertension management and cardiovascular disease prevention in the region.

Association of Pulse Volume Recording at Ankle with Total and Cardiovascular Mortality in Hemodialysis Patients

Pulse volume recording is an accurate modality for detecting arterial occlusion in the lower extremities. There are two indexes of pulse volume recording measured at ankle, percentage of mean arterial pressure (%MAP) and upstroke time (UT). The aim of the study was to examine the ability of %MAP and UT for the prediction of overall and cardiovascular mortality in hemodialysis (HD) patients. In 197 routine HD patients, ankle %MAP, ankle UT, and ankle-brachial index (ABI) were automatically measured by Colin VP-1000 instrument. Fourteen cardiovascular mortality and 29 overall mortalities were documented during 2.7 ± 0.6 years follow-up. In the univariate analysis, in addition to co-morbidities and traditional clinical parameters, increased total mortality was associated with decreased ABI, ABI < 0.9, increased %MAP and UT, %MAP > 50%, and UT > 169 ms (p < 0.041) and increased cardiovascular mortality was associated with increased UT and %MAP > 50% (p < 0.022). After multivariate analysis, increased %MAP and %MAP > 50% (p < 0.047) were still the predictors of total mortality and %MAP > 50% (p = 0.024) was still the predictor of cardiovascular mortality. In HD patients, we found that ankle %MAP and %MAP > 50% could predict total mortality and ankle %MAP > 50% could predict cardiovascular mortality in the multivariate analysis. Hence, assessment of %MAP from pulse volume recording at ankle might be helpful in identifying the high-risk group for poor prognosis in HD patients.

Global Vascular Guidelines on the Management of Chronic Limb-Threatening Ischemia

GUIDELINE SUMMARY

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

UPSTROKE TIME PER CARDIAC CYCLE IS ASSOCIATED WITH CARDIOVASCULAR PROGNOSIS IN TYPE 2 DIABETES

Objective: Upstroke time per cardiac cycle (UTCC) in the lower extremities has been found to be predictive of cardiovascular mortality in the general population. Therefore, the purpose of the study was to test the associations between increasing UTCC and outcomes in patients with type 2 diabetes. Methods: A total of 452 patients with type 2 diabetes (age, 67.5 ± 8.6 years; male, 54%) registered in a share-care program participated in the study at an outpatient clinic in Taipei Veterans General Hospital across a mean of 5.8 years. Primary outcomes were all-cause mortality hospitalization for coronary artery disease, stroke, revascularization, amputation, and diabetic foot syndrome. Secondary end-point outcome was all-cause mortality. Results: Increment of UTCC associations with primary and secondary outcomes were undertaken prior to baseline characteristic adjustments. A UTCC of 20.1% exhibited the greatest area under curve (AUC), sensitivity, and specificity balance to predict composite events in receiver operating curves (AUC, 0.63 [P = .001]; sensitivity, 67.7%; specificity, 54.9%). Sixty-four composite events and 17 deaths were identified from medical records. UTCC ≥20.1% was associated with the occurrence of composite events and an increased risk of mortality. For composite events, an adjusted hazard ratio (HR) of 2.45 and 95% confidence interval (CI) of 1.38 to 4.35 (P = .002) were calculated. For all-cause mortality, an adjusted HR of 1.91 and 95% CI of 0.33 to 10.99 (P = .467) were calculated. Conclusion: Increasing UTCC was associated with cardiovascular outcomes in patients with type 2 diabetes. Therefore, UTCC is advocated as a noninvasive screening tool for ambulatory patients with type 2 diabetes. Abbreviations: CAD = coronary artery disease; CI = confidence interval; eGFR = estimated glomerular filtration rate; HR = hazard ratio; PAD = peripheral artery disease; UTCC = upstroke time per cardiac cycle.

Global vascular guidelines on the management of chronic limb-threatening ischemia

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

Difference in the risk profiles of carotid-femoral pulse wave velocity: results from two community-based studies in China and Sweden

Carotid-femoral pulse wave velocity (cfPWV) and its risk factors may differ between various populations. Few studies have compared the risk profiles associated with cfPWV in different ethnic populations. The study population included 4321 subjects from Shanghai, China (n = 1272, age 75.0 ± 6.5 years, female 57.3%) and Malmö, Sweden (n = 3049, age 72.5 ± 5.5 years, female 60.4%). cfPWV was measured using the SphygmoCor device in both cohorts, with some difference in the determination of pulse transmission distance. The median cfPWV was 8.9 and 10.1 m/s (P < 0.001) respectively in the Chinese and Swedish subjects. cfPWV was associated (P < 0.05) with age, body mass index (BMI), mean arterial pressure (MAP), heart rate, fasting plasma glucose and serum triglycerides in both populations. The standardized effect size (m/s) associated with age (0.091 vs. 0.048, P < 0.001) and fasting plasma glucose (0.025 vs. 0.012, P = 0.046) was greater in the Swedish than Chinese subjects, whereas those with BMI (0.046 vs. 0.008, P < 0.001), MAP (0.079 vs. 0.067, P = 0.016), and heart rate (0.057 vs. 0.046, P = 0.036) were greater in Chinese. No difference was observed in those associated with serum triglycerides (P = 0.128). cfPWV was additionally associated with sex, serum total cholesterol, and on antihypertensive medication in the Swedish subjects, and with serum uric acid in the Chinese subjects (P ≤ 0.041). In conclusion, Chinese and Swedish subjects shared similar major risk factors of arterial stiffness, but with some differences in the strength of associations.

Association Between Prevalence of Peripheral Artery Disease and Radiation Exposure in the Atomic Bomb Survivors

Background Past reports suggested that total-body irradiation at 0.5 to 1.0 Gy could be responsible for atherosclerosis. Peripheral artery disease ( PAD ) is a manifestation of systematic atherosclerosis. Whether the consequences of a low-to-moderate dose of radiation include increased risk of PAD remains to be determined. The purpose of this study was to examine the association between radiation exposure and prevalence of PAD among Japanese atomic bomb survivors. Methods and Results Radiation exposure from the atomic bombing was assessed in 3476 participants (41.1% men, mean age 74.8 years with SD 6.4 years) with a cross-sectional survey in 2010 to 2014. Left- and right-side ankle-brachial indexes and upstroke time ( UT ) were obtained using oscillometric VP -2000. PAD was defined as an ankle-brachial index of 1.0 or less or a prior history related to revascularization. UT was considered a sensitive marker of early-stage PAD . Association between radiation exposure and PAD or UT was assessed using multivariable regression analyses with adjustment for potential confounding factors. Of 3476 participants, 79 (2.3%) were identified as having prevalent PAD . Multivariate logistic regression analysis indicated that radiation dose was unrelated to PAD prevalence (odds ratio, 0.83; 95% confidence interval [0.57-1.21]). UT appeared to increase with radiation dose, but the increase was not statistically significant (1.09 ms/Gy; 95% confidence interval [-0.17 to 2.36]). Conclusions We found no clear association of radiation dose with PAD , but it remains to be determined whether UT is associated with radiation dose.

Brachial-ankle pulse wave velocity, cardio-ankle vascular index, and prognosis

Background

Brachial–ankle pulse wave velocity (baPWV) and cardio-ankle vascular index (CAVI) are indices of arterial stiffness, and several studies have used these indices. However, there is no comprehensive review of these parameters in the prognostic significance.

Methods

The aim of this study was to review the articles exploring the prognostic significance of these parameters. Articles demonstrating independent significance after multivariate analysis on the Cox proportional hazards model were defined as “successful.” The success rate was compared using Fisher’s exact test. In addition, multivariate logistic regression analysis was performed to explore the independent determinants of the success of prognostic prediction.

Results

The success rate of the baPWV articles (65.7% [46/70]) tended to be higher than that of the CAVI articles (40.0% [6/15]; P=0.083). Multivariate analysis demonstrated that log (number of patients) (OR 11.20, 95% CI 2.45–51.70, P=0.002) and dialysis population (OR 0.28, 95% CI 0.08–0.94, P=0.039) were positive and negative independent determinants of the success of prognostic prediction, respectively. In addition, after redefining two studies as the absence of arteriosclerosis obliterans (ASO) exclusion, baPWV (OR 3.36, 95% CI 0.86–13.20, P=0.083) and the existence of exclusion criteria of ASO (OR 3.08, 95% CI 0.96–9.93, P=0.060) exhibited statistical tendency in the multivariate analysis.

Conclusion

This study demonstrated that the number of study participants and dialysis population were the independent determinants of the success of prognostic prediction. This study also showed the importance of exclusion criteria of ASO when using these indices. In addition, a prospective large-scale study to confirm the superiority in the prognostic prediction of these indices is warranted.

Comparison of ankle-brachial index and upstroke time in association with target organ damage: the Northern Shanghai Study

A recent study indicated that upstroke time per cardiac cycle (UTCC) in lower extremities is equivalent to ankle-brachial index (ABI) in diagnosing peripheral arterial disease and in predicting cardiovascular mortality. In this study, we aimed to compare ABI and UTCC in relation to target organ damage. A cohort of 1841 elderly participants from the Northern Shanghai Study was studied. ABI and UTCC were measured using VP-1000 device. Target organ damage including left ventricular hypertrophy and diastolic dysfunction, carotid intima-media thickness and plaque, carotid-femoral pulse wave velocity (CF-PWV), and renal damage, were evaluated by standardized methods. In correlation analysis, ABI and UTCC both significantly correlated with CF-PWV, carotid plaque, and estimated glomerular filtration rate, but not with cardiac damage. Compared with ABI, UTCC showed stronger correlation with CF-PWV. When ABI and UTCC separately put into fully adjusted multivariate logistic regression models, both ABI (OR: 2.27; 95% CI: 1.63-3.17) and UTCC (OR: 1.63; 95% CI: 1.18-2.24) significantly associated with carotid plaque, but only UTCC significantly associated with increased CF-PWV (OR: 1.66; 95% CI: 1.15-2.42) and renal damage (OR: 1.63; 95% CI: 1.07-2.47). When ABI and UTCC both put into multivariate stepwise logistic regression models together with covariates, consistent results were observed. In ROC curve analysis, after adjusted for cofounding factors, UTCC showed slightly greater area under curve than ABI in detecting increased CF-PWV (area under curve: 0.79 vs. 0.78; P = .008); however, no difference was observed between UTCC and ABI in discriminating renal damage and carotid plaque. In conclusion, compared with ABI, UTCC showed significantly stronger association with vascular and renal damage in this elderly Chinese cohort.