Association between arterial stiffness and peripheral artery disease as measured by radial artery tonometry

Estimated pulse-wave velocity predicts survival in patients requiring extracorporeal membrane oxygenation

INTRODUCTION

Arterial stiffness, measured by estimated pulse-wave velocity is a known predictor of major adverse cardiovascular events, however its predictive value in patients requiring extracorporeal membrane oxygenation (ECMO) is unknown.

METHODS

A retrospective cohort study was performed at the London Health Science Centre in London, Canada between 1996-2021, totaling 255 patients requiring ECMO. Estimated pulse-wave velocity (ePWV) was calculated using an algorithm from the Reference Values for Arterial Stiffness Collaboration. Recorded outcomes included in-hospital death, ischemic stroke, hemorrhagic stroke, renal failure and need for renal replacement therapy (RRT). For adjusted analysis, survival-to-discharge was used. Multivariate logistic regression and propensity-score matching were utilized to control for confounding.

RESULTS

On univariate analysis, higher ePWV was significantly predictive of ischemic stroke (OR 1.676, p = 0.0002) and in-hospital death (OR 1.20, p = 0.006), but insignificant for predicting hemorrhagic stroke (OR 1.07, p = 0.710), and appeared protective for renal failure (OR 0.88 [0.78-0.99], p = 0.034) and RRT (OR 0.87, p = 0.027). On multivariate analysis and propensity-score matching, five of six models demonstrated ePWV as an independent predictor of survival-to-discharge. (OR 0.70, p = 0.00,021; OR 0.72, p = 0.0002; OR 0.87, p = 0.045; OR 0.85, p = 0.013; OR 0.57, p = 0.012).

CONCLUSIONS

ePWV is a promising marker for risk-stratification in ECMO patients. Further investigation is required to better delineate the role of arterial health assessment in disease trajectory and strengthen the validity of AS as a marker of interest in medical and surgical management.

Oscillometric measurement of the ankle-brachial index and the estimated carotid-femoral pulse wave velocity improves the sensitivity of an automated device in screening peripheral artery disease

Background and aims

To overcome the time and personnel constraints of the Doppler method, automated, four-limb blood pressure monitors were recently developed. Their additional functions, such as measuring the estimated carotid-femoral pulse wave velocity (ecfPWV), have been, thus far, less studied. We aimed to compare the sensitivity and specificity of different ankle-brachial index (ABI), toe-brachial index (TBI), and ecfPWV measurement methodologies to evaluate their contribution to peripheral artery disease (PAD) screening.

Methods

Among 230 patients (mean age 64 ± 14 years), ABI measurements were performed using a Doppler device and a manual sphygmomanometer. The Doppler ABI was calculated by taking the higher, while the modified Doppler ABI by taking the lower systolic blood pressure of the two ankle arteries as the numerator, and the higher systolic blood pressure of both brachial arteries as the denominator. The automated ABI measurement was carried out using an automatic BOSO ABI-system 100 PWV device, which also measured ecfPWV. TBI was obtained using a laser Doppler fluxmeter (Periflux 5000) and a photoplethysmographic device (SysToe). To assess atherosclerotic and definitive PAD lesions, vascular imaging techniques were used, including ultrasound in 160, digital subtraction angiography in 66, and CT angiography in four cases.

Results

ROC analysis exhibited a sensitivity/specificity of 70.6%/98.1% for the Doppler ABI (area under the curve, AUC = 0.873), 84.0%/94.4% for the modified Doppler ABI (AUC = 0.923), and 61.5%/97.8% for the BOSO ABI (AUC = 0.882) at a cutoff of 0.9. Raising the cutoff to 1.0 increased the sensitivity of BOSO to 80.7%, with the specificity decreasing to 79.1%. The ecfPWV measurement (AUC = 0.896) demonstrated a 63.2%/100% sensitivity/specificity in predicting atherosclerotic lesions at a cutoff of 10 m/s. Combining BOSO ABI and ecfPWV measurements recognized 89.5% of all PAD limbs.

Conclusion

The combined BOSO ABI and ecfPWV measurements may help select patients requiring further non-invasive diagnostic evaluation for PAD. The user-friendly feasibility may make it suitable for screening large populations.

Comparison of Parameters for Assessment of Carotid Stiffness and Their Association with Carotid Atherosclerosis in Rural Australian Adults: A Pilot Study

Carotid stiffness has been associated with the development and progression of carotid artery disease and is an independent factor for stroke and dementia. There has also been a lack of comparison of different ultrasound-derived carotid stiffness parameters and their association with carotid atherosclerosis. This pilot study aimed to investigate the associations between carotid stiffness parameters (derived via ultrasound echo tracking) and the presence of carotid plaques in Australian rural adults. In cross-sectional analyses, we assessed forty-six subjects (68 ± 9 years; mean ± SD) who underwent carotid ultrasound examinations. Carotid stiffness was assessed by a noninvasive echo-tracking method, measuring and comparing multiple carotid stiffness parameters, including stroke change in diameter (ΔD), stroke change in lumen area (ΔA), β- stiffness index, pulse wave velocity beta (PWV-β), compliance coefficient (CC), distensibility coefficient (DC), Young's elastic modulus (YEM), Peterson elastic modulus (Ep), and strain. Carotid atherosclerosis was assessed bilaterally by the presence of plaques in the common and internal carotid arteries, while carotid stiffness was assessed at the right common carotid artery. β-stiffness index, PWV-β, and Ep were significantly higher (p = 0.006, p = 0.004, p = 0.02, respectively), whilst ΔD, CC, DC, and strain were lower among subjects with carotid plaques (p = 0.036, p = 0.032, p = 0.01, p = 0.02, respectively) comparing to subjects without carotid plaques. YEM and ΔA did not significantly differ among the groups. Carotid plaques were associated with age, history of stroke, coronary artery disease, and previous coronary interventions. These results suggest that unilateral carotid stiffness is associated with the presence of carotid plaques.

Combined Evaluation of Arterial Stiffness and Blood Pressure Promotes Risk Stratification of Peripheral Arterial Disease

BACKGROUND

Previous studies have reported the separate association of arterial stiffness (AS) and blood pressure with peripheral arterial disease (PAD).

OBJECTIVES

The aim of this study was to investigate the risk stratification capacity of AS on incident PAD beyond blood pressure status.

METHODS

A total of 8,960 participants from Beijing Health Management Cohort were enrolled at the first health visit between 2008 and 2018 and then followed until the incidence of PAD or 2019. Elevated AS was defined as brachial-ankle pulse-wave velocity (baPWV) >1,400 cm/s, including moderate stiffness (1,400 ≤ baPWV <1,800 cm/s) and severe stiffness (baPWV ≥1,800 cm/s). PAD was defined as ankle-brachial index <0.9. A frailty Cox model was used to calculate the HR, integrated discrimination improvement, and net reclassification improvement.

RESULTS

During follow-up, 225 participants (2.5%) developed PAD. After adjusting for confounding factors, the highest risk for PAD was observed in the group with elevated AS and blood pressure (HR: 2.253; 95% CI: 1.472-3.448). Among participants with ideal blood pressure and those with well-controlled hypertension, PAD risk was still significant for severe AS. The results remained consistent in multiple sensitivity analyses. In addition, baPWV significantly improved the predictive capacity for PAD risk beyond systolic and diastolic blood pressures (integrated discrimination improvement 0.020 and 0.190, net reclassification improvement 0.037 and 0.303).

CONCLUSIONS

This study suggests the clinical importance of combined evaluation and control of AS and blood pressure for the risk stratification and prevention of PAD.

Inter-arm differences in regional arterial stiffness and geometry lead to inter-arm systolic blood pressure differences: A modelling study

An inter-arm systolic blood pressure difference (ISBPD), if substantial in magnitude (typically defined as ≥10 mmHg), is a potential cardiovascular risk factor in adults, due to its association with cardiovascular events/mortality. A substantial ISBPD occurs in approximately 10% of the adult population, and, although associations with vascular disease and elevated stiffness have been reported, the mechanisms underlying ISBPD remain unknown. The aim of this study was to investigate whether inter-arm differences in segmental pulse wave velocity, cross-sectional area, or vascular bed compliance/resistance could give rise to substantial differences in brachial pressures between arms; for example, due to differences in pulse wave transmission and reflection. Using an established one-dimensional model of the major systemic arteries, pulse wave velocity (PWV) was uniformly increased or decreased in arteries of 1) the supra-aortic region leading up to the arm, 2) the brachial region, 3) the forearm, and 4) all of these (entire arm pathway); for the left arm, right arm, and both arms. Cross-sectional area and vascular bed compliance and resistance of the arms were similarly varied. Inter-arm differences in segmental PWV and cross-sectional area (but not bilateral changes) led to associated substantial inter-arm SBP differences, which were observed with changes to brachial, forearm and/or entire arm pathways and were related to altered transmission of forward waves and amplitude/timing of reflected waves. Vascular bed compliance and resistance had minimal influence. We conclude that inter-arm differences in arterial stiffness and geometry may contribute to inter-arm systolic blood pressure differences, warranting further investigation.

Cardiac Rehabilitation in Peripheral Artery Disease in a Tertiary Center-Impact on Arterial Stiffness and Functional Status after 6 Months

Background and Objectives: Cardiac rehabilitation (CR) plays an essential role in peripheral artery disease (PAD), leading to improved functional status, increased quality of life, and reduced arterial stiffness. We aimed to assess factors associated with clinical improvement 6 months after enrolment in a rehabilitation program at an academic medical center in north-eastern Europe. Materials and Methods: We conducted a prospective cohort study on 97 patients with PAD admitted to a single tertiary referral center. At the 6-months follow-up, 75 patients (77.3%) showed improved clinical status. We analyzed demographics and clinical and paraclinical parameters in order to explore factors associated with a favorable outcome. Results: Hypertension (p = 0.002), diabetes mellitus (p = 0.002), dyslipidemia (p = 0.045), and obesity (p = 0.564) were associated with no clinical improvement. Smoking cessation (p < 0.001), changing sedentary lifestyle (p = 0.032), and improvement of lipid and carbohydrate profile as well as functional status parameters and ambulatory arterial stiffness index (p = 0.008) were factors associated with clinical improvement at the 6-months follow-up. Conclusions: PAD patients require an integrative, multidisciplinary management to maintain functional status and increase quality of life. Improving carbohydrate and lipid profile, adopting a healthy lifestyle, quitting smoking and increasing exercise capacity are predictors for clinical improvement 6 months after enrolment in a CR program.

Predictors of arterial stiffness in adolescents and adults with type 1 diabetes: a cross-sectional study

INTRODUCTION

Individuals with type 1 diabetes have increased arterial stiffness compared with age-matched healthy controls. Our aim was to determine which hemodynamic and demographic factors predict arterial stiffness in this population.

RESEARCH DESIGN AND METHODS

Carotid-femoral pulse wave velocity (cfPWV) was examined in 41 young adults and adolescents with type 1 diabetes without microvascular complications. Two ordinary least squares regression analyses were performed to determine multivariate relationships between cfPWV (loge) and (1) age, duration of diabetes, sex, and hemoglobin A1c and (2) augmentation index (AIx), mean arterial pressure, flow-mediated dilation (FMD), and heart rate. We also examined differences in macrovascular outcome measures between sexes.

RESULTS

Age, sex, and FMD provided unique predictive information about cfPWV in these participants with type 1 diabetes. Despite having similar cardiovascular risk factors, men had higher cfPWV compared with women but no differences were observed in other macrovascular outcomes (including FMD and AIx).

CONCLUSIONS

Only age, sex, and FMD were uniquely associated with arterial stiffness in adolescents and adults with uncomplicated type 1 diabetes. Women had less arterial stiffness and similar nitric oxide-dependent endothelial function compared with men. Larger, prospective investigation is warranted to determine the temporal order of and sex differences in arterial dysfunction in type 1 diabetes.

Body mass-normalized moderate dose of dietary nitrate intake improves endothelial function and walking capacity in patients with peripheral artery disease

Peripheral artery disease (PAD) is characterized by the accumulation of atherosclerotic plaques in the lower extremity conduit arteries, which impairs blood flow and walking capacity. Dietary nitrate has been used to reduce blood pressure (BP) and improve walking capacity in PAD. However, a standardized dose for PAD has not been determined. Therefore, we sought to determine the effects of a body mass-normalized moderate dose of nitrate (0.11 mmol nitrate/kg) as beetroot juice on serum nitrate/nitrite, vascular function, walking capacity, and tissue oxygen utilization capacity in patients with PAD. A total of 11 patients with PAD received either nitrate supplement or placebo in a randomized crossover design. Total serum nitrate/nitrite, resting BP, brachial and popliteal artery endothelial function (flow-mediated dilation, FMD), arterial stiffness (pulse-wave velocity, PWV), augmentation index (AIx), maximal walking distance and time, claudication onset time, and skeletal muscle oxygen utilization were measured pre- and postnitrate and placebo intake. There were significant group × time interactions (P < 0.05) for serum nitrate/nitrite, FMD, BP, walking distance and time, and skeletal muscle oxygen utilization. The nitrate group showed significantly increased serum nitrate/nitrite (Δ1.32 μM), increased brachial and popliteal FMD (Δ1.3% and Δ1.7%, respectively), reduced peripheral and central systolic BP (Δ-4.7 mmHg and Δ-8.2 mmHg, respectively), increased maximal walking distance (Δ92.7 m) and time (Δ56.3 s), and reduced deoxygenated hemoglobin during walking. There were no changes in PWV, AIx, or claudication (P > 0.05). These results indicate that a body-mass normalized moderate dose of nitrate may be effective and safe for reducing BP, improving endothelial function, and improving walking capacity in patients with PAD.

Impact of in-hospital blood pressure variability on clinical outcomes in patients with symptomatic peripheral arterial disease

Various types of blood pressure (BP) variability have been recognized as risk factors for future cardiovascular events. However, the prognostic impact of in-hospital BP variability in patients with symptomatic peripheral arterial disease (PAD) has not yet been thoroughly investigated. A total of 386 patients with PAD who underwent endovascular therapy in two hospitals were retrospectively included. BP variability was assessed by the coefficient of variation (CV) of systolic BP measured during hospitalization by trained nurses. The primary endpoint was a composite of major adverse cardiovascular events (cardiovascular death, acute coronary syndrome, stroke, and hospitalization for heart failure) and major adverse limb events (major amputation, acute limb ischemia, and surgical limb revascularization). The mean systolic BP and the CV of systolic BP during hospitalization were 130.8 ± 15.7 mmHg and 11.2 ± 4.1%, respectively. During the median follow-up period of 22 months, 80 patients (21%) reached the primary endpoint. Receiver operating characteristic curve analysis showed that the CV of systolic BP significantly predicted major adverse cardiovascular and limb events (area under the curve 0.60, best cutoff value 9.8, P = 0.01). Using the best cutoff value, patients with high BP variability (n = 242) had a higher risk of clinical events than those with low BP variability (n = 144) (26% vs. 12%, P < 0.001). Multivariable analysis indicated that the CV of systolic BP, age, hemodialysis, and atrial fibrillation were associated with the primary endpoint. In conclusion, greater in-hospital systolic BP variability was associated with major adverse cardiovascular and limb events in patients with symptomatic PAD undergoing endovascular therapy.

Insulin increases central aortic stiffness in response to hyperglycemia in healthy humans: A randomized four-arm study

INTRODUCTION

Increasing arterial stiffness is a feature of vascular aging that is accelerated by conditions that enhance cardiovascular risk, including diabetes mellitus. Multiple studies demonstrate divergence of carotid-femoral pulse wave velocity and augmentation index in persons with diabetes mellitus, though mechanisms responsible for this are unclear.

MATERIALS AND METHODS

We tested the effect of acutely and independently increasing plasma glucose, plasma insulin, or both on hemodynamic function and markers of arterial stiffness (including carotid-femoral pulse wave velocity, augmentation index, forward and backward wave reflection amplitude, and wave reflection magnitude) in a four-arm, randomized study of healthy young adults.

RESULTS

Carotid-femoral pulse wave velocity increased only during hyperglycemic-hyperinsulinemia (+0.36 m/s; p = 0.032), while other markers of arterial stiffness did not change (all p > 0.05). Heart rate (+3.62 bpm; p = 0.009), mean arterial pressure (+4.14 mmHg; p = 0.033), central diastolic blood pressure (+4.16 mmHg; p = 0.038), and peripheral diastolic blood pressure (+4.09 mmHg; p = 0.044) also significantly increased during hyperglycemic-hyperinsulinemia.

CONCLUSIONS

Hyperglycemic-hyperinsulinemia acutely increased cfPWV, heart rate, mean arterial pressure, and diastolic blood pressure in healthy humans, perhaps reflecting enhanced sympathetic tone. Whether repeated bouts of hyperglycemia with hyperinsulinemia contribute to chronically-enhanced arterial stiffness remains unknown.

Traditional and non-traditional risk factors for peripheral artery disease development/progression in patients with type 2 diabetes: the Rio de Janeiro type 2 diabetes cohort study

BACKGROUND

The prognostic importance of non-traditional risk factors for peripheral artery disease (PAD) development/progression is scarcely studied in diabetes. We investigated if carotid intima-media thickness (CIMT) and carotid-femoral pulse wave velocity (cf-PWV) added prognostic information beyond traditional cardiovascular risk markers for PAD outcomes.

METHODS

Ankle-brachial index (ABI) was measured at baseline and after a median of 91 months of follow-up in 681 individuals with type 2 diabetes. Multivariate Cox regressions examined the associations between the candidate variables and the outcome. PAD development/progression was defined by a reduction in ABI ≥ 0.15 (to a level < 0.9) or limb revascularization procedures, lower-extremity amputations or death due to PAD. The improvement in risk discrimination was assessed by increases in C-statistics of the models.

RESULTS

Seventy-seven patients developed/progressed PAD: 50 reduced ABI to < 0.9, seven had lower-limb revascularizations, and 20 had amputations or death. Age, male sex, diabetes duration, presence of microvascular complications (peripheral neuropathy and diabetic kidney disease), baseline HbA1c, 24-h systolic BP (SBP) and mean cumulative office SBP and LDL-cholesterol were associated with PAD development/progression in several models. CIMT and cf-PWV were additionally associated with PAD outcomes, and their inclusion further improved risk discrimination (with C-statistic increases between 0.025 and 0.030). The inclusion of ambulatory 24-h SBP, instead of office SBP, also improved PAD risk discrimination.

CONCLUSIONS

Increased CIMT and aortic stiffness are associated with greater risks of developing/progressing PAD, beyond traditional risk factors, in type 2 diabetes.

Sex modification of the association of the radial augmentation index and incident hypertension in a Chinese community-based population

BACKGROUND

Arterial stiffness, as assessed by aortic ultrasound and pulse wave velocity, is associated with incident hypertension. However, there is still no consensus on whether the augmentation index (AI) affects new onset of hypertension. This study investigated the relationship of radial AI (rAI) and incident hypertension in a Chinese community-based population without hypertension at baseline.

METHOD

A total of 1,615 Chinese non-hypertensive participants from an atherosclerosis cohort in Beijing, China were included in our analysis. Baseline rAI normalized to heart rate of 75 beats/min (rAIp75) was obtained using HEM-9000AI. New-onset hypertension was defined as blood pressure ≥ 140/90 mmHg or self-reported hypertension or taking anti-hypertensive medications at the follow up survey. Multivariate regression models were used to evaluate the impact of rAIp75 on the risk of new-onset hypertension.

RESULTS

After a mean 2.35-year follow-up, 213 (13.19%) participants developed incident hypertension. No significant relation between rAIp75 and incident hypertension was observed in the whole population after adjustment for possible confounders (adjusted odds ratio (OR) and 95% confidence interval (CI): 1.09 [0.95-1.27];P = 0.2260). However, rAIp75 was significantly associated with incident hypertension in women, but not in men (adjusted OR and 95% CI: 1.29 [1.06-1.56],P = 0.0113 for women; 0.91 [0.72-1.15],P = 0.4244 for men; P for interaction = 0.0133).

CONCLUSIONS

Sex modified the effect of the rAI on incident hypertension in a Chinese, community-based, non-hypertensive population. Screening of the rAI could be considered in women with a high risk of hypertension for the purpose of primary intervention.

The association between pulse wave analysis, carotid-femoral pulse wave velocity and peripheral arterial disease in patients with ischemic heart disease

INTRODUCTION

Functional changes in peripheral arterial disease (PAD) could play a role in higher cardiovascular risk in these patients.

METHODS

123 patients who underwent elective coronary angiography were included. Ankle-brachial index (ABI) was measured and arterial stiffness parameters were derived with applanation tonometry.

RESULTS

6 patients (4.9%) had a previously known PAD (Rutherford grade I). Mean ABI was 1.04 ± 0.12, mean subendocardial viability ratio (SEVR) 166.6 ± 32.7% and mean carotid-femoral pulse wave velocity (cfPWV) 10.3 ± 2.4 m/s. Most of the patients (n = 81, 65.9%) had coronary artery disease (CAD). There was no difference in ABI among different degrees of CAD. Patients with zero- and three-vessel CAD had significantly lower values of SEVR, compared to patients with one- and two-vessel CAD (159.5 ± 32.9%/158.1 ± 31.5% vs 181.0 ± 35.2%/166.8 ± 27.8%; p = 0.048). No significant difference was observed in cfPWV values. Spearman's correlation test showed an important correlation between ABI and SEVR (r = 0.196; p = 0.037) and between ABI and cfPWV (r = - 0.320; p ≤ 0.001). Multiple regression analysis confirmed an association between cfPWV and ABI (β = - 0.210; p = 0.003), cfPWV and mean arterial pressure (β = 0.064; p < 0.001), cfPWV and age (β = 0.113; p < 0.001) and between cfPWV and body mass index (BMI (β = - 0.195; p = 0.028), but not with arterial hypertension, dyslipidemia, diabetes mellitus or smoking status. SEVR was not statistically significantly associated with ABI using the same multiple regression model.

CONCLUSION

Reduced ABI was associated with increased cfPWV, but not with advanced CAD or decreased SEVR.

Use of the ankle-brachial index combined with the percentage of mean arterial pressure at the ankle to improve prediction of all-cause mortality in type 2 diabetes mellitus: an observational study

Background

Peripheral artery disease (PAD) in the lower extremities is a common complication of type 2 diabetes and has been shown to be associated with mortality. The ankle-brachial index (ABI) is a simple noninvasive method to screen PAD, but this method has limited sensitivity. We hypothesized that using the percentage of mean arterial pressure (%MAP) in combination with the ABI would improve the prediction of mortality.

Methods

We retrospectively collected data from patients with type 2 diabetes who had undergone ABI and  %MAP measurements at our hospital. We separated the cohort into four groups according to their ABI and  %MAP values, and we examined whether these indices were associated with mortality.

Results

A total of 5569 patients (mean age, 65 ± 11 years) were enrolled. During the follow-up period (median, 22.9 months), 266 (4.8%) of the enrolled patients died. The combination of ABI and  %MAP was significantly more effective than ABI alone for predicting mortality (C index of 0.62, 95% confidence interval [CI] of 0.57 to 0.65 vs. C index of 0.57, 95% CI of 0.53 to 0.62; P = 0.038). In multivariate analysis (with a reference group defined by ABI > 0.90 and  %MAP ≤ 45%), the highest risk of mortality was seen in patients with ABI ≤ 0.90 and  %MAP > 45% (hazard ratio = 2.045 [95% CI 1.420, 2.945], P < 0.001).

Conclusions

The use of  %MAP alongside ABI appears to significantly improve the prediction of all-cause mortality in patients with type 2 diabetes.

Effects of Remote Ischaemic Preconditioning on Arterial Stiffness in Patients Undergoing Lower Limb Angiographic Procedures: A Randomised Clinical Trial

OBJECTIVES

Remote ischaemic preconditioning (RIPC) is a phenomenon that promotes protection of tissues and organs against ischaemia reperfusion injury. RIPC has been shown to reduce myocardial and renal injury but its effect on arterial stiffness in patients undergoing lower limb digital subtraction angiography (DSA) is unknown. The aim of this study was to evaluate the effect of RIPC on arterial stiffness in patients with peripheral arterial disease (PAD) undergoing lower limb DSA.

METHODS

In the RIPC intervention, the blood pressure cuff on the arm was inflated to 200 mmHg or to 20 mmHg above systolic pressure, and in the sham intervention to 20 mmHg. For both, the procedure was repeated for four five minute cycles at five minute intervals between the cycles. Changes in heart rate corrected augmentation index (AIx@75), augmentation index (AIx), carotid femoral pulse wave velocity (PWV), and haemodynamic parameters were measured before and 24 h after DSA.

RESULTS

111 (RIPC 54, sham 57) patients with symptomatic lower limb PAD scheduled for DSA were randomised. 102 patients (RIPC 47, sham 55) were included in final analysis. RIPC significantly improved AIx (-5.46% in RIPC and -1.45% in sham group; p = .05), but not AIx@75 (-4.88% in RIPC and -1.38% in sham group; p = .07) or PWV (-0.41 m/s in RIPC and -0.27 m/s in sham group; p = .74). In the RIPC group a significant reduction in AIx (p = .002) and AIx@75 (p = .003) was noted after stenting when compared with the sham intervention. AIx (p = .001), AIx@75 (p = .002), mean arterial (p = .01), peripheral (p = .02), and central systolic blood pressure (p = .006) were significantly reduced only in the RIPC group 24 h after DSA.

CONCLUSION

This study evaluates for the first time the effects of RIPC on arterial stiffness parameters in patients with symptomatic PAD following DSA. RIPC may modulate arterial stiffness following a DSA procedure and is more pronounced in patients after stent placement.

Peripheral arterial stiffness is correlated with intrarenal arteriolosclerosis according to biopsies from patients with kidney disease

AIM

To investigate the possible associations between intrarenal arteriolosclerosis as determine by renal biopsy and endothelial function as well as arterial stiffness measured by peripheral arterial tonometry (EndoPAT).

METHODS

This was a cross-sectional study. Patients who underwent both renal biopsy and EndoPAT were recruited, and intrarenal arteriolosclerosis was graded according to the pathological slice. Endothelial function and arterial stiffness were both measured by EndoPAT and were expressed by the reactive hyperemia index (RHI) and augmentation index (AIx), respectively. AIx@75, representing the AIx standardized to a heart rate of 75 bpm was also determined.

RESULTS

In total, 113 patients were assessed, the mean age was 51 ± 13, and 68.1% were men. The natural logarithm RHI (LnRHI), AIx and AIx@75 were significantly different among different grades of intrarenal arteriolosclerosis (P = .030, P < .001, P < .001, respectively). In the multivariable adjusted model, for every SD increase in the AIx and AIx@75, the odds of having more severe arteriolosclerosis were 2.506 times (95% confidence interval [CI] 1.464-4.288, P = .001] and 3.191 times (95% CI 1.780-5.719, P < .001) higher, respectively, and the association between the LnRHI and intrarenal arteriolosclerosis was nullified (P = .059). The positive values of the AIx and AIx@75 for the diagnosis of severe intrarenal arteriolosclerosis were 0.80 (95% CI 0.73-0.88, P < .001) and 0.78 (95% CI 0.70-0.87, P < .001), respectively.

CONCLUSION

Subjects with more severe intrarenal arteriolosclerosis have greater peripheral vascular stiffness; AIx and AIx@75 reflected peripheral vascular stiffness could be used to identify patients with severe intrarenal arteriolosclerosis.

Impacts of aquatic walking on arterial stiffness, exercise tolerance, and physical function in patients with peripheral artery disease: a randomized clinical trial

Peripheral artery disease (PAD) is an atherosclerotic disease that is associated with attenuated vascular function, cardiorespiratory capacity, physical function, and muscular strength. It is essential to combat these negative effects on health by incorporating lifestyle interventions to slow disease progression, such as exercise. We sought to examine the effects of aquatic walking exercise on cardiovascular function, cardiorespiratory capacity [maximal volume of oxygen consumption (V̇o_2max)], exercise tolerance [6-min walking distance (6MWD)], physical function, muscular strength, and body composition in patients with PAD. Patients with PAD (n = 72) were recruited and randomly assigned to a 12-wk aquatic walking training group (AQ, n = 35) or a control group (CON, n = 37). The AQ group performed walking and leg exercises in waist-to-chest-deep water. Leg arterial stiffness [femoral-to-ankle pulse wave velocity (legPWV)], heart rate (HR), blood pressure (BP), ankle-to-brachial index (ABI), V̇o_2max, 6MWD, physical function, muscular strength, body composition, resting metabolic rate (RMR), and flexibility were measured before and after 12 wk. There were significant group × time interactions (P < 0.05) after 12 wk for legPWV and HR, which significantly decreased (P < 0.05) in AQ, and V̇o_2max, 6MWD, physical function, and muscular strength, which significantly increased (P < 0.05) in AQ, compared with no changes in CON. There were no significant differences (P > 0.05) for BP, ABI, RMR, or flexibility after 12 wk. Interestingly, there was relatively high adherence (84%) to the aquatic walking exercise program in this population. These results suggest that aquatic walking exercise is an effective therapy to reduce arterial stiffness and resting HR and improve cardiorespiratory capacity, exercise tolerance, physical function, and muscular strength in patients with PAD.NEW & NOTEWORTHY The results of this study reveal for the first time that aquatic walking exercise can decrease arterial stiffness and improve exercise tolerance, cardiorespiratory capacity, and muscular strength in patients with peripheral artery disease (PAD). Aquatic walking exercise training demonstrates relatively high exercise adherence in this population. Aquatic walking exercise training may be a useful therapeutic intervention for improving physical function in patients with PAD.

Association between critical limb ischemia and arterial stiffness measured by brachial artery oscillometry

Background

Elevated arterial stiffness is associated with increased cardiovascular mortality. The relationship between arterial stiffness and critical limb ischemia (CLI) is not well established.

Objectives

The objective of this study is to analyze the relationship between arterial stiffness indices and the degree of limb ischemia measured by the ankle-brachial index (ABI).

Methods

A cross-sectional study comparing patients with CLI and controls. Arterial stiffness was measured using brachial artery oscillometry. The arterial stiffness indices pulse wave velocity (PWV) and augmentation index normalized to 75 beats/min (AIx@75) were determined. Multiple linear regression was applied to identify predictors of arterial stiffness indices.

Results

Patients in the CLI group had higher PWV (12.1±1.9 m/s vs. 10.1±1.9 m/s, p < 0.01) and AIx@75 (31.8±7.8% vs. 17.5±10.8%, p < 0.01) than controls. Central systolic pressure was higher in the CLI group (129.2±18.4 mmHg vs. 115.2±13.1 mmHg, p < 0.01). There was an inverse relationship between AIx@75 and ABI (Pearson coefficient = 0.24, p = 0.048), but there was no relationship between ABI and PWV (Pearson coefficient = 0.19, p = 0.12). In multiple regression analysis, reduced ABI was a predictor of elevated levels of AIx@75 (β = -25.02, p < 0.01).

Conclusions

Patients with CLI have high arterial stiffness measured by brachial artery oscillometry. The degree of limb ischemia, as measured by the ABI, is a predictor of increased AIx@75. The increased AIx@75 observed in CLI may have implications for the prognosis of this group of patients with advanced atherosclerosis.

Applications of arterial stiffness markers in peripheral arterial disease

Arterial stiffness has been analyzed in many different population groups with the objective of identifying cardiovascular risk early and performing specific therapeutic interventions. Increased arterial stiffness affects the capacity of the aorta and elastic arteries to adapt to pressure variations during the cardiac cycle. The main markers of arterial stiffness are pulse wave velocity (PWV), augmentation index (AIx) and central aortic pressure. They can be measured noninvasively. Patients with coronary disease or on hemodialysis who have elevated PWV or AIx have increased mortality. The association with peripheral arterial disease has been studied little. The objective of this review is to demonstrate the applicability and utility of assessing measures of arterial stiffness in patients with peripheral arterial disease.

Radial Artery Tonometry is Associated With Major Adverse Cardiac Events in Patients With Peripheral Artery Disease

BACKGROUND

Peripheral artery disease (PAD) is associated with increased arterial stiffness, as measured by an increasing radial artery augmentation index (AIX). However, it has not yet been clearly demonstrated whether AIX is associated with adverse cardiovascular outcomes in a PAD population.

MATERIALS AND METHODS

Seventy-two patients with PAD were recruited between 2011 and 2016. Radial artery applanation tonometry was performed at a baseline visit, and the central AIX, normalized to 75 beats/min, and the peripheral AIX were calculated using pulse wave analysis. Incident major adverse cardiac events (MACEs) were identified by subsequent chart review.

RESULTS

Study subjects had comorbidities commonly associated with PAD including a high prevalence of hypertension (93%), hyperlipidemia (85%), coronary artery disease (39%), and diabetes mellitus (39%). During a median follow-up period of 34 mo (interquartile range 29-38), 14 patients experienced a MACE. In a univariate Cox proportional hazards model, a 10-unit increase in the peripheral AIX was significantly associated with a 54% increased rate of MACE (hazard ratio [HR] 1.54, 95% confidence interval [CI] 1.06-2.22, P = 0.02), but central AIX, normalized to 75 beats/min, was not (HR 1.33, 95% CI 0.71-2.47, P = 0.37). In a multivariable model adjusted for coronary artery disease, age, and Rutherford category the peripheral AIX remained significantly associated with MACE (HR 1.70, 95% CI 1.10-2.62, P = 0.02).

CONCLUSIONS

Increased arterial stiffness, as measured by the peripheral AIX, was independently associated with an increased rate of MACE in patients with PAD. The use of radial artery tonometry should be contemplated as a tool for risk stratification in patients with PAD.

Oxidative Stress and Arterial Dysfunction in Peripheral Artery Disease

Peripheral artery disease (PAD) is an atherosclerotic disease characterized by a narrowing of the arteries in the lower extremities. Disease manifestations are the result of more than just reduced blood flow, and include endothelial dysfunction, arterial stiffness, and inflammation. Growing evidence suggests that these factors lead to functional impairment and decline in PAD patients. Oxidative stress also plays an important role in the disease, and a growing amount of data suggest a link between arterial dysfunction and oxidative stress. In this review, we present the current evidence for the involvement of endothelial dysfunction, arterial stiffness, and inflammation in the pathophysiology of PAD. We also discuss the links between these factors and oxidative stress, with a focus on nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2)-derived reactive oxygen species (ROS) and decreased nitric oxide (NO) bioavailability. Finally, the potential therapeutic role of NOX2 antioxidants for improving arterial function and functional status in PAD patients is explored.

Serum resistin is associated with impaired endothelial function and a higher rate of adverse cardiac events in patients with peripheral artery disease

OBJECTIVE

Resistin is a hormone that has been associated with metabolic syndrome and cardiovascular disease. The role of resistin in patients with peripheral artery disease (PAD) has not been fully explored. This study seeks to understand the relationship between serum resistin, vascular function, and cardiovascular outcomes in patients with PAD.

METHODS

There were 106 patients with PAD who were recruited between 2011 and 2016. Patients attended a baseline visit during which a comprehensive vascular physiology assessment including medical and surgical history, radial artery tonometry, and flow mediated-vasodilation (FMD) was completed. A blood sample was drawn, and serum resistin was assayed using enzyme-linked immunosorbent assay kits. Using the time of study enrollment as the time of origin, incident major adverse cardiac events (MACEs) were identified by subsequent chart review and defined as a composite end point of myocardial infarction, coronary revascularization, transient ischemic attack, stroke, or death from a cardiac cause.

RESULTS

Patients had a mean age of 68 ± 8 years, were largely white (75%), and had comorbidities commonly associated with PAD including hypertension (92%), hyperlipidemia (87%), coronary artery disease (37%), and diabetes mellitus (38%). After stratification by resistin quartile, higher resistin quartiles were significantly associated with an older age, a greater number of pack-years smoked, and a lower estimated glomerular filtration rate. Despite similar comorbidities and medication use, endothelial function, as measured by FMD, was significantly lower with increasing resistin quartile (I, 9.1% ± 3.3%; II, 7.1% ± 3.5%; III, 5.8% ± 4.0%; IV, 5.6% ± 3.5%; P = .002). In multivariable linear regression, higher resistin quartiles (III and IV) were associated with lower FMD relative to quartile I after adjusting for several patient characteristics, medications, and comorbidities (III, -2.26 [95% confidence interval (CI), -4.51 to -0.01; P = .05]; IV, -2.53 [95% CI, -4.87 to -0.20; P = .03]). During a median follow-up period of 36 months (interquartile range, 29-45 months), 21 patients experienced the primary end point. In a Cox proportional hazards model adjusted for smoking status, coronary artery disease, and age, each 1 ng/mL increase in resistin was associated with a 10% increased risk of MACEs (hazard ratio, 1.10; 95% CI, 1.00-1.20; P = .04).

CONCLUSIONS

In patients with PAD, higher levels of resistin were associated with impaired endothelial function and an increased rate of MACEs. These results suggest that resistin may be a marker or effector of impaired vascular physiology and adverse cardiac outcomes in patients with PAD. Further research is needed to determine the potential mechanisms by which resistin may impair endothelial function and increase MACEs in this population.

Longitudinal pulsatility in arterial occlusion

This pictorial essay aims to generate attention and inform sonographers and clinicians by remembering the "longitudinal pulsatility" as an evocative B-mode echographic sign of arterial occlusion, when the artery exhibits a systolic axial motion instead of its normal radial pulsatility.

Arterial Stiffness is Independently Associated with Severity of Carotid Siphon Calcifications in Community-Dwelling Older Adults: The Atahualpa Project

BACKGROUND

Knowledge on the association between arterial stiffness and intracranial atherosclerosis is limited. Here, we aimed to assess whether the aortic pulse wave velocity (PWV)-used as a surrogate of arterial stiffness-might independently predict severity of carotid siphon calcifications (CSCs), used as a marker of atherosclerosis.

METHODS

Of 437 Atahualpa residents aged 60 years or older, 300 (69%) underwent head computed tomography (CT) (for CSC assessment), brain magnetic resonance imaging (for identification of neuroimaging signatures of cerebral small vessel disease [SVD]), and aortic PWV determinations (for arterial stiffness estimation). Ordinal logistic regression models were constructed to predict severity of CSC (as the dependent variable) according to levels of aortic PWV after adjusting for demographics, cardiovascular risk factors, and neuroimaging signatures of SVD.

RESULTS

Grade 1 CSC were noticed in 120 (40%) subjects, grade 2 in 84 (28%), grade 3 in 73 (24%), and grade 4 in 23 (8%). The mean PWV was 10.4 ± 1.8 m/s, which increased from 9.8 ± 1.3 to 11.1 ± 2.1 m/s in individuals with grades 1 and 4 CSC, respectively (P <.001). The most parsimonious ordinal logistic regression model adjusted for relevant confounders showed a significant association between aortic PWV and severity of CSC. In this model, a change of 1 unit of aortic PWV increased the odds of CSC severity by 1.22 (95% confidence interval 1.07-1.39; P = .004).

CONCLUSIONS

The monotonically increased odds of aortic PWV among subjects with different grades of CSC, suggest that aortic PWV may be a marker for identifying candidates for CT screening in the search of CSC.

High-intensity handgrip training lowers blood pressure and increases heart rate complexity among postmenopausal women: a pilot study

OBJECTIVE

Handgrip exercise is an emerging strategy for resting blood pressure (BP) reduction requiring minimal time and exercise effort. However, the research literature is currently limited to handgrip protocol designs predominantly prescribing sustained grip contractions, with little assessment of alternative options. Furthermore, our understanding of the utility of handgrip exercise would be strengthened by an evaluation of the physiological mechanisms driving BP reductions and an assessment of the interindividual response variability. As such, this research was designed to perform an initial evaluation of the pragmatic effectiveness of a novel at-home, high-intensity, unilateral (nondominant) handgrip exercise training program in reducing resting BP, while simultaneously exploring mediators of BP change including a neurocardiac index of autonomic nervous control [heart rate (HR) variability], measures of arterial stiffness (radial augmentation index and carotid-radial pulse wave velocity), and cardiovascular reactivity to psychophysiological stressors.

METHODS

Postmenopausal women were recruited to complete 8 weeks of handgrip exercise training. Aforementioned measures of resting BP and mediators of BP change were acquired at the midway point and end of training.

RESULTS

All participants (n=17) completed training with high self-reported adherence (96.9%) and improvement in grip strength (2.7±2.4kg, P<0.05). Handgrip training reduced resting systolic BP (-5.1±7.7 mmHg, P<0.05) and improved HR complexity (sample entropy: 0.24±0.31, P<0.05), without significant changes to resting diastolic BP, HR, or arterial stiffness (all P>0.05).

CONCLUSION

This pilot study successfully shows the potential utility of high-intensity intermittent handgrip exercise for improvements in cardiovascular health among postmenopausal women, with additional research required to further explore the underlying physiological mechanisms driving such improvements.