Subclavian Artery Stenosis: Prevalence, Risk Factors, and Association With Cardiovascular Diseases

Non-coronary atherosclerosis

During the last decades, the clinical and research interest in atherosclerosis has been mostly focused on coronary arteries. After the publications of the European Society Guidelines and AHA/ACC Guidelines on Peripheral artery diseases, and of the Registry REduction in Atherothrombosis for Continued Health Registry, there has been an increased interest in atherosclerosis of the lower extremity arteries and its presence in multifocal disease. However, awareness in the general population and the medical community of non-coronary artery diseases, and of its major prognostic implications remain relatively low. The aim of this general review stemming out of an ESC Working Group on Peripheral Circulation meeting in 2011 is to enhance awareness of this complex disease highlighting the importance of the involvement of atherosclerosis at different levels with respect to clinical presentation, diagnosis, and co-existence of the disease in the distinct arterial territories. We also emphasize the need of an interdisciplinary approach to face the broad and complex spectrum of multifocal disease, and try to propose a series of tentative recommendations and measures to be implemented in non-coronary atherosclerosis.

The systolic blood pressure difference between arms and cardiovascular disease in the Framingham Heart Study

BACKGROUND

An increased interarm systolic blood pressure difference is an easily determined physical examination finding. The relationship between interarm systolic blood pressure difference and risk of future cardiovascular disease is uncertain. We described the prevalence and risk factor correlates of interarm systolic blood pressure difference in the Framingham Heart Study (FHS) original and offspring cohorts and examined the association between interarm systolic blood pressure difference and incident cardiovascular disease and all-cause mortality.

METHODS

An increased interarm systolic blood pressure difference was defined as ≥ 10 mm Hg using the average of initial and repeat blood pressure measurements obtained in both arms. Participants were followed through 2010 for incident cardiovascular disease events. Multivariable Cox proportional hazards regression analyses were performed to investigate the effect of interarm systolic blood pressure difference on incident cardiovascular disease.

RESULTS

We examined 3390 (56.3% female) participants aged 40 years and older, free of cardiovascular disease at baseline, mean age of 61.1 years, who attended a FHS examination between 1991 and 1994 (original cohort) and from 1995 to 1998 (offspring cohort). The mean absolute interarm systolic blood pressure difference was 4.6 mm Hg (range 0-78). Increased interarm systolic blood pressure difference was present in 317 (9.4%) participants. The median follow-up time was 13.3 years, during which time 598 participants (17.6%) experienced a first cardiovascular event, including 83 (26.2%) participants with interarm systolic blood pressure difference ≥ 10 mm Hg. Compared with those with normal interarm systolic blood pressure difference, participants with an elevated interarm systolic blood pressure difference were older (63.0 years vs 60.9 years), had a greater prevalence of diabetes mellitus (13.3% vs 7.5%,), higher systolic blood pressure (136.3 mm Hg vs 129.3 mm Hg), and a higher total cholesterol level (212.1 mg/dL vs 206.5 mg/dL). Interarm systolic blood pressure difference was associated with a significantly increased hazard of incident cardiovascular events in the multivariable adjusted model (hazard ratio 1.38; 95% CI, 1.09-1.75). For each 1-SD-unit increase in absolute interarm systolic blood pressure difference, the hazard ratio for incident cardiovascular events was 1.07 (95% CI, 1.00-1.14) in the fully adjusted model. There was no such association with mortality (hazard ratio 1.02; 95% CI 0.76-1.38).

CONCLUSIONS

In this community-based cohort, an interarm systolic blood pressure difference is common and associated with a significant increased risk for future cardiovascular events, even when the absolute difference in arm systolic blood pressure is modest. These findings support research to expand clinical use of this simple measurement.

Distal neuroprotection system as option for right subclavian artery ostial recanalization

We present the case of a 49-year-old woman with neurological symptoms and severe atherosclerosis of aortic arch branches affecting subclavian and carotid arteries. Our patient has a history of transient ischemic attack and recurrent paresthesias of her right arm. We present a double access intervention using a distal embolic neuroprotection device during ostial right subclavian artery recanalization. We recommend that use of an embolic protection device in right subclavian artery ostial recanalization should be considered.

Vitamin D status, functional decline, and mortality in peripheral artery disease

Associations of vitamin D levels with prospectively measured functional decline and mortality in people with lower extremity peripheral artery disease (PAD) are unknown. We determined whether lower baseline vitamin D levels are associated with a faster decline in functional performance and higher mortality among people with and without PAD. A total of 658 participants (395 with PAD) underwent baseline measurement of 25-hydroxyvitamin D (DiaSorin radioimmunoassay), a 6-minute walk test, 4-meter walking velocity and the Short Physical Performance Battery (SPPB), and were followed annually for up to 4 years. Analyses were adjusted for age, sex, race, body mass index, comorbidities, the ankle-brachial index, and other confounders. Among participants with PAD, lower baseline vitamin D levels were associated with a faster decline in the 6-minute walk (vitamin D < 30 nmol/L: -70.0 feet/year; vitamin D 30 to < 50 nmol/L: -72.3 feet/year; vitamin D 50 to < 75 nmol/L: -35.5 feet/year; vitamin D 75 to < 120 nmol/L: -35.9 feet/year; p trend=0.012). PAD participants with vitamin D < 30 nmol/L had a faster decline in the SPPB and 6-minute walk compared to those with levels of 50 to < 75 (p=0.034 and p=0.04, respectively). Among participants without PAD, lower vitamin D was associated with a faster decline in the fast 4-meter walking velocity (p trend=0.003). There were no significant associations of baseline vitamin D levels with all-cause or cardiovascular disease mortality in PAD or non-PAD participants. In conclusion, among individuals with and without PAD, low vitamin D status was associated with a faster decline in some measures of functional performance but was not related to mortality.

Ankle brachial index values, leg symptoms, and functional performance among community-dwelling older men and women in the lifestyle interventions and independence for elders study

Background

The prevalence and significance of low normal and abnormal ankle brachial index (ABI) values in a community‐dwelling population of sedentary, older individuals is unknown. We describe the prevalence of categories of definite peripheral artery disease (PAD), borderline ABI, low normal ABI, and no PAD and their association with lower‐extremity functional performance in the LIFE Study population.

Methods and Results

Participants age 70 to 89 in the LIFE Study underwent baseline measurement of the ABI, 400‐m walk, and 4‐m walking velocity. Participants were classified as follows: definite PAD (ABI <0.90), borderline PAD (ABI 0.90 to 0.99), low normal ABI (ABI 1.00 to 1.09), and no PAD (ABI 1.10 to 1.40). Of 1566 participants, 220 (14%) had definite PAD, 250 (16%) had borderline PAD, 509 (33%) had low normal ABI, and 587 (37%) had no PAD. Among those with definite PAD, 65% were asymptomatic. Adjusting for age, sex, race, body mass index, smoking, and comorbidities, lower ABI was associated with longer mean 400‐m walk time: (definite PAD=533 seconds; borderline PAD=514 seconds; low normal ABI=503 seconds; and no PAD=498 seconds [P<0.001]). Among asymptomatic participants with and without PAD, lower ABI values were also associated with longer 400‐m walk time (P<0.001) and slower walking velocity (P=0.042).

Conclusion

Among older community‐dwelling men and women, 14% had PAD and 49% had borderline or low normal ABI values. Lower ABI values were associated with greater functional impairment, suggesting that lower extremity atherosclerosis may be a common preventable cause of functional limitations in older people.

Clinical Trial Registration

URL: http://clinicaltrials.gov/ Unique identifier: NCT01072500.

Long-term results of primary stenting for subclavian artery disease

OBJECTIVES

To evaluate initial and long-term results of endovascular therapy (EVT) for symptomatic subclavian artery (SCA) disease.

BACKGROUND

EVT for SCA disease has a similar success rate as open surgery, but the long-term patency of EVT alone is uncertain.

METHODS

We retrospectively studied 59 consecutive patients (42 males and 17 females) with 60 lesions. Mean patient age was 68 ± 10 years. Clinical symptoms were vertebrobasilar insufficiency in 21 patients (35.0%), arm claudication in 20 patients (33.3%), angina pectoris in 12 patients (20%), severe arm ischemia in 3 patients (5.0%), vascular access insufficiency in 3 patients (5.0%), and leg ischemia in 1 patient (1.7%). A total of 57 stents were implanted. All patients were followed up at 1, 3, 6, and 12 months after the procedure and annually thereafter.

RESULTS

The technical success rate was 93.3%. All patients for whom technical success was obtained received stents. There were four technical failures, all of which were owing to the failure of crossing the wire in occluded lesions. There were no procedure-related deaths. There were two stroke events (3.4%) and one embolic event (1.7%). Primary patency rates were 94.9, 90.8, and 85.8% at 1, 3, and 5 years, respectively.

CONCLUSIONS

EVT for SCA disease is an effective treatment with regard to initial success rate, clinical efficacy, and long-term primary patency. This minimally invasive procedure is appropriate as the treatment of first choice for proximal subclavian arterial obstructive disease.

Subclavian steal syndrome successfully treated with a novel application of embolic capture angioplasty

Subclavian artery stenosis can lead to subclavian steal syndrome. Endovascular treatment of these lesions has become the preferred modality. We describe the successful use of embolic capture angioplasty for the treatment of a patient with subclavian artery stenosis resulting in subclavian steal syndrome.

Relationship between inter-arm difference in systolic blood pressure and arterial stiffness in community-dwelling older adults

A significant inter-arm difference in systolic blood pressure (IADSBP) has recently been associated with worse cardiovascular outcomes. The authors hypothesized that part of this association is mediated by arterial stiffness, and examined the relationship between significant IADSBP and carotid-femoral pulse wave velocity (CF-PWV) in a sample from the Baltimore Longitudinal Study of Aging. Of 1045 participants, 50 (4.8%) had an IADSBP ≥10 mm Hg at baseline, and 629 had completed data from ≥2 visits (for a total of 1704 visits during 8 years). CF-PWV was significantly higher in patients with an IADSBP ≥10 mm Hg (7.3±1.9 vs 8.2±2, P=.002). Compared with others, patients with IADSBP ≥10 mm Hg also had higher body mass index, waist circumference, and triglycerides; higher prevalence of diabetes; and lower high-density lipoprotein (HDL) cholesterol (P<.001 for all). A significant association with IADSBP ≥10 mm Hg was observed for CF-PWV in both cross-sectional (odds ratio [OR], 1.19; 95% confidence interval [CI], 1.06-1.87; P=.01) and longitudinal (OR, 1.15; 95% CI, 1.03-1.29; P=.01) multivariate analyses. Female sex, Caucasian race, high body mass index (plus diabetes and low HDL cholesterol only cross-sectionally) were other independent correlates of IADSBP ≥10 mm Hg. Significant IADSBP is associated with increased arterial stiffness in community-dwelling older adults.

Decline in functional performance predicts later increased mobility loss and mortality in peripheral arterial disease

OBJECTIVES

We hypothesized that a greater 2-year decline in office-based functional performance measures would be associated with greater mobility loss and mortality in people with peripheral arterial disease (PAD).

BACKGROUND

Associations of decline in functional performance with clinically important outcomes in patients with PAD are unknown.

METHODS

A total of 440 men and women with PAD completed the 6-min walk test and measures of walking velocity at baseline and annually for 2 years. Participants were categorized into tertiles according to their functional decline between baseline and 2-year follow-up and were followed annually after the functional change assessment. Cox proportional hazard models were used to assess relations between the 2-year change in functional performance with later mortality and mobility loss, with adjustments for age, sex, race, ankle brachial index, comorbidities, and other confounders.

RESULTS

A total of 102 participants (23.2%) died during a median follow-up of 44.5 months after functional change was assessed. Of 319 participants without baseline mobility disability, 60 (18.8%) developed mobility loss after functional change was assessed. Participants in the tertile with the greatest 6-min walk decline had the highest subsequent mobility loss (hazard ratio [HR]: 3.50; 95% confidence interval [CI]: 1.56 to 7.85; p = 0.002), all-cause mortality (HR: 2.16; 95% CI: 1.28 to 3.64; p = 0.004), and cardiovascular disease mortality (HR: 2.45; 95% CI: 1.08 to 5.54; p = 0.031), compared with those with the smallest 6-min walk decline. Greater declines in fastest-paced 4-m walking velocity were associated with higher mobility loss (p trend = 0.018), all-cause mortality (p trend = 0.01), and cardiovascular mortality (p trend = 0.004).

CONCLUSIONS

Participants with PAD with declining functional performance are at increased risk for later mobility loss and mortality.

Home-based walking exercise intervention in peripheral artery disease: a randomized clinical trial

IMPORTANCE

Clinical practice guidelines state there is insufficient evidence to support advising patients with peripheral artery disease (PAD) to participate in a home-based walking exercise program.

OBJECTIVE

To determine whether a home-based walking exercise program that uses a group-mediated cognitive behavioral intervention, incorporating both group support and self-regulatory skills, can improve functional performance compared with a health education control group in patients with PAD with and without intermittent claudication.

DESIGN, SETTING, AND PATIENTS

Randomized controlled clinical trial of 194 patients with PAD, including 72.2% without classic symptoms of intermittent claudication, performed in Chicago, Illinois between July 22, 2008, and December 14, 2012.

INTERVENTIONS

Participants were randomized to 1 of 2 parallel groups: a home-based group-mediated cognitive behavioral walking intervention or an attention control condition.

MAIN OUTCOMES AND MEASURES

The primary outcome was 6-month change in 6-minute walk performance. Secondary outcomes included 6-month change in treadmill walking, physical activity, the Walking Impairment Questionnaire (WIQ), and Physical and Mental Health Composite Scores from the 12-item Short-Form Health Survey.

RESULTS

Participants randomized to the intervention group significantly increased their 6-minute walk distance ([reported in meters] 357.4 to 399.8 vs 353.3 to 342.2 for those in the control group; mean difference, 53.5 [95% CI, 33.2 to 73.8]; P < .001), maximal treadmill walking time (intervention, 7.91 to 9.44 minutes vs control, 7.56 to 8.09; mean difference, 1.01 minutes [95% CI, 0.07 to 1.95]; P = .04), accelerometer-measured physical activity over 7 days (intervention, 778.0 to 866.1 vs control, 671.6 to 645.0; mean difference, 114.7 activity units [95% CI, 12.82 to 216.5]; P = .03), WIQ distance score (intervention, 35.3 to 47.4 vs control, 33.3 to 34.4; mean difference, 11.1 [95% CI, 3.9 to 18.1]; P = .003), and WIQ speed score (intervention, 36.1 to 47.7 vs control, 35.3-36.6; mean difference, 10.4 [95% CI, 3.4 to 17.4]; P = .004).

CONCLUSION AND RELEVANCE

A home-based walking exercise program significantly improved walking endurance, physical activity, and patient-perceived walking endurance and speed in PAD participants with and without classic claudication symptoms. These findings have implications for the large number of patients with PAD who are unable or unwilling to participate in supervised exercise programs.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00693940.

Subclavian revascularization in the age of thoracic endovascular aortic repair and comparison of outcomes in patients with occlusive disease

OBJECTIVE

Open surgical revascularization for subclavian artery occlusive disease (OD) has largely been supplanted by endovascular treatment despite the excellent long-term patency of bypass. The indications for carotid-subclavian bypass (C-SBP) and subclavian transposition (ST) have been recently expanded with the widespread application of thoracic endovascular aortic repair (TEVAR), primarily to augment proximal landing zones or treat endovascular failures. This study was performed to determine the outcomes of patients undergoing C-SBP/ST in the context of contemporary endovascular therapies and evolving indications.

METHODS

A prospective database including all procedures performed at a single institution from 2002 to 2012 was retrospectively queried for patients who underwent subclavian revascularization for TEVAR or OD indications. Patient demographics and perioperative outcomes were recorded. Patency was determined by computed tomography angiography in the TEVAR group. Noninvasive studies were used for the OD patients. Life-table methods were used to estimate patency, reintervention, and survival.

RESULTS

Of 139 procedures identified, 101 were performed for TEVAR and 38 for OD. All TEVAR patients underwent C-SBP/ST to augment landing zones (49% preoperative; 41% intraoperative), treat arm ischemia (8% postoperative), or for internal mammary artery salvage (2%). OD patients had a variety of indications, including failed stent/arm fatigue, 49%; asymptomatic >80% internal carotid stenosis with concurrent subclavian occlusion, 18%; symptomatic cerebrovascular OD, 13%; redo bypass, 8%; and coronary-subclavian steal, 5%. Differences in postoperative stroke and death, primary patency, or freedom from reintervention were not significant. The 30-day postoperative stroke, death, and combined stroke/death rates were, respectively, 10.8%, 5.8%, and 13.7% for the entire cohort; 8.9%, 7.1%, and 12.9% in TEVAR patients; and 15.8%, 2.6%, and 15.8% in OD patients. The 1- and 3-year primary patencies were, respectively, 94% and 94% for TEVAR and 93% and 73% for OD patients. Survival was similar between the groups, with an estimated survival rate of 88% at 1 year and 76% at 5 years.

CONCLUSIONS

Stroke risk in this contemporary series of C-SBP/ST performed for TEVAR and OD indications may be higher than previously reported in historical series. In TEVAR patients, this may be attributed to procedural complexity of the TEVAR in patients requiring subclavian revascularization. In OD patients, this is likely due to the changing patient population that requires more frequent concomitant carotid interventions. Despite the short-term morbidity, excellent bypass durability and equivalent long-term patient survival can be anticipated.

Comparative effectiveness study of self-directed walking exercise, lower extremity revascularization, and functional decline in peripheral artery disease

OBJECTIVE

Among individuals with peripheral artery disease (PAD), we compared annual change in 6-minute walk performance between participants who neither underwent lower extremity revascularization nor walked for exercise (group 1, reference), those who walked regularly for exercise (group 2), and those who underwent lower extremity revascularization (group 3).

METHODS

Participants were recruited from Chicago-area vascular laboratories and followed annually. Change in 6-minute walk was calculated beginning at the study visit preceding lower extremity revascularization or exercise behavior and continuing for 1 additional year after the therapy was reported. Results are adjusted for age, sex, race, comorbidities, and other confounders.

RESULTS

Of 348 PAD participants, 43 underwent revascularization during median follow-up of 84 months. Adjusted annual declines in 6-minute walk were -96.6 feet/year for group 1, -49.9 feet/year for group 2, and -32.6 feet/year for group 3 (P < .001). Forty-one percent of revascularizations were not associated with ankle-brachial index (ABI) improvement. When group 3 was limited to participants with ABI improvement ≥0.15 after revascularization, annual adjusted changes in 6-minute walk were -97.7 feet/year for group 1, -46.5 feet/year for group 2, and +68.1 feet/year for group 3 (P < .001). When group 3 was limited to participants without ABI improvement ≥0.15 after revascularization, annual adjusted changes in 6-minute walk were -99.2 feet/year for group 1, -48.0 feet/year for group 2, and -61.7 feet/year for group 3 (P < .001).

CONCLUSIONS

A large proportion of PAD participants did not have ABI improvement of at least 0.15 at follow-up study visit after revascularization. The benefits of lower extremity revascularization in patients with PAD appear closely tied to improvements in the ABI after revascularization.

Declining walking impairment questionnaire scores are associated with subsequent increased mortality in peripheral artery disease

OBJECTIVES

This study determined whether greater 2-year declines in Walking Impairment Questionnaire (WIQ) stair climbing, distance, or speed scores were associated with higher all-cause and cardiovascular disease (CVD) mortality among men and women with lower extremity peripheral artery disease (PAD).

BACKGROUND

Associations of decline in the WIQ with mortality among people with PAD are unknown.

METHODS

Participants were 442 men and women with PAD identified from Chicago area medical centers. The WIQ was completed at baseline and at 2-year follow-up. Cox proportional hazard models were used to assess associations across categories of 2-year changes in WIQ stair climbing, WIQ distance, and WIQ speed scores with subsequent all-cause and CVD mortality, adjusting for age, sex, race, ankle-brachial index, body mass index, smoking, comorbidities, and other covariates.

RESULTS

One hundred twenty-three participants (27.8%) died during a median follow-up of 4.7 years after the 2-year change in WIQ score measurements. Forty-five participants died from CVD. Adjusting for covariates, participants with WIQ score declines ≥20.0 points had higher all-cause mortality (hazard ratio [HR]: 1.93, 95% confidence interval [CI]: 1.01 to 3.68 for WIQ stair climbing; HR: 2.34, 95% CI: 1.15 to 4.75 for WIQ distance; and HR: 3.55, 95% CI: 1.57 to 8.04 for WIQ speed, respectively) compared with participants with ≥20.0 point improvement in each of the corresponding WIQ categories. Participants with ≥20.0 point declines in the WIQ distance score had higher CVD mortality (HR: 4.56, 95% CI: 1.30 to 16.01) compared with those with ≥20.0 point improvement in the WIQ distance score.

CONCLUSIONS

Patients with PAD who experienced ≥20.0 point declines in the WIQ stair climbing, distance, and speed scores had a higher rate of all-cause mortality compared with those with less declines in each WIQ score.

Ethnic differences in ankle brachial index are present in middle-aged individuals without peripheral arterial disease

INTRODUCTION

To better understand the basis for previously reported ethnic differences in ankle brachial index (ABI), we investigated whether these differences were present in individuals without known peripheral arterial disease (PAD).

METHODS

We used data from National Health and Nutrition Examination surveys (NHANES 1999-2004) to determine whether ethnic differences were present in respondents without PAD (1 ≤ ABI ≤ 1.3). We assessed whether ethnicity was an independent predictor of ABI and ankle systolic blood pressure (SBP) in linear regression models that adjusted for conventional and novel cardiovascular risk factors. To minimize effects of atherosclerosis on ABI, we studied adults aged ≤ 60 years, and also repeated our analyses in a subset aged ≤ 50 years that did not have risk factors for PAD.

RESULTS

3348 participants aged ≤ 60 years were included in the study. Mean ABI was 1.11 in non-Hispanic Blacks (NHB) and 1.13 in non-Hispanic Whites (NHW) (P < 0.0001). In multivariable linear regression analysis that adjusted for age, gender, ethnicity, smoking, height, diabetes, brachial SBP, dyslipidemia, diabetes, renal function, concurrent cardiovascular disease, and plasma levels of homocysteine, fibrinogen and C-reactive protein, NHB had lower ABI than NHW (β = -0.03 ± 0.004, P < 0.00001). Although, NHBs had higher ankle SBP than NHWs (by 5.4 mm Hg), NHBs had a lower mean ankle SBP (β = -3.663 mm Hg ± 0.500, P < 0.0001) after adjusting for clinical covariates, including brachial SBP, in multivariable analysis.

CONCLUSION

Ethnic differences in ABI are present in middle-aged adults at low risk for peripheral atherosclerosis.

Sudden cardiac arrest with acute myocardial infarction induced by left subclavian artery occlusion in a patient with prior coronary artery bypass surgery

Multivascular preventive and therapeutic approaches are necessary in patients with coronary artery disease because atherosclerosis has a common systemic pathogenesis. We present a rare case of sudden cardiac arrest with acute myocardial infarction induced by the total occlusion of left subclavian artery (LSCA) in a patient with a history of previous coronary artery bypass surgery using the left internal mammary artery. We initially performed blind-puncture of left brachial artery, attempting percutaneous coronary intervention because pulses were absent in both upper and lower extremities. However, the cause of sudden cardiac arrest was atherosclerotic total occlusion of LSCA. The patient was stabilized after successful revascularization of LSCA by percutaneous transluminal angioplasty with stent insertion.

Aortic arch vessel disease and rationale for echocardiographic screening

Atherosclerosis of the proximal branches of the aortic arch has compelling clinical implications that warrant the application of direct noninvasive detection of the disease. The prevalence of aortic arch vessel disease in an aging and at-risk community and clinical population has been underreported and undertreated despite an associated increase of all-cause and cardiovascular mortality. Intrathoracic duplex imaging has been validated as an accurate noninvasive tool to detect, characterize, and follow native aortic arch vessel disease and its sequelae and correction. Such duplex techniques are easily integrated into routine echocardiography with focused training and minimal time investment in the examination. A paucity of available resources exists across disciplines regarding ultrasonographic investigation of these supra-aortic trunk vessels, including textbooks, journal articles, seminars, and manuals. This review has been compiled to familiarize physicians and sonographers with the relevant anatomy, pathophysiology, treatment, and diagnostic duplex surveillance of aortic arch vessel disease. Illustrative cases along with clinical rationale are discussed with the intent to facilitate the integration of arch vessel duplex imaging into the scope and practice of echocardiography.

Prospective relationship of low cardiovascular risk factor profile at younger ages to ankle-brachial index: 39-year follow-up--the Chicago Healthy Aging Study

Background

Data are sparse regarding the long-term association of favorable levels of all major cardiovascular disease risk factors (RFs) (ie, low risk [LR]) with ankle-brachial index (ABI).

Methods and Results

In 2007–2010, the Chicago Healthy Aging Study reexamined a subset of participants aged 65 to 84 years from the Chicago Heart Association Detection Project in Industry cohort (baseline examination, 1967–1973). RF groups were defined as LR (untreated blood pressure ≤120/≤80 mm Hg, untreated serum cholesterol <200 mg/dL, body mass index <25 kg/m², not smoking, no diabetes) or as 0 RFs, 1 RF, or 2+ RFs based on the presence of blood pressure ≥140/≥90 mm Hg or receiving treatment, serum cholesterol ≥240 mg/dL or receiving treatment, body mass index ≥30 kg/m², smoking, or diabetes. ABI at follow-up was categorized as indicating PAD present (≤0.90), as borderline PAD (0.91 to 0.99), or as normal (1.00 to 1.40). We included 1346 participants with ABI ≤1.40. After multivariable adjustment, the presence of fewer baseline RFs was associated with a lower likelihood of PAD at 39-year follow-up (P for trend is <0.001). Odds ratios (95% CIs) for PAD in persons with LR, 0 RFs, or 1 RF compared with those with 2+ RFs were 0.14 (0.05 to 0.44), 0.28 (0.13 to 0.59), and 0.33 (0.16 to 0.65), respectively; findings were similar for borderline PAD (P for trend is 0.005). The association was mainly due to baseline smoking status, cholesterol, and diabetes. Remaining free of adverse RFs or improving RF status over time was also associated with PAD.

Conclusions

LR profile in younger adulthood (ages 25 to 45) is associated with the lowest prevalence of PAD and borderline PAD 39 years later.

Subclavian steal syndrome presenting as recurrent pulmonary oedema associated with acute left ventricular diastolic dysfunction

Subclavian steal syndrome typically presents as angina in patients with internal mammary artery grafts. Atypical clinical presentations have been rarely described. We report an unusual case of subclavian steal syndrome presenting as pulmonary oedema with acute left ventricular diastolic dysfunction and preserved ejection fraction in a patient with internal mammary artery graft and severe stenosis of the proximal left subclavian artery. After successful angioplasty and stenting of subclavian artery, the patient remained asymptomatic for six months, but then experienced acute diastolic dysfunction and recurrent pulmonary oedema associated with critical subclavian in-stent restenosis with stent deformation. This report points out that, in patients with internal mammary-to-LAD grafts, subclavian steal syndrome may present as acute left ventricular diastolic dysfunction and pulmonary oedema even in the presence of normal ejection fraction.

A diabetic patient with asymptomatic multiple arterial disease

The authors present the case of a 73-year-old diabetic woman who was referred to hospital because of the suspicion of lower limb peripheral arterial stenosis. During evaluations signs of the subclavian artery occlusion were found. In addition to diabetes, the patient had several risk factors revealed by medical history. Subclavian artery occlusion was solved by angiography guided stenting, and angiography also showed the presence of abnormalities in renal arteries. This case draws the attention to the importance of screening old diabetic patients for arterial stenosis and the importance of accurate risk factor assessment. Orv. Hetil., 2012, 153, 1475–1479.

The Group Oriented Arterial Leg Study (GOALS) to improve walking performance in patients with peripheral arterial disease

People with lower extremity peripheral artery disease (PAD) have greater functional impairment and faster functional decline than those without PAD. We describe methods for the Group Oriented Arterial Leg Study (GOALS), an ongoing randomized controlled clinical trial designed to determine whether a Group-Mediated Cognitive Behavioral (GMCB) intervention improves functional performance in PAD participants, compared to a health education control condition. In GOALS, PAD participants were randomized to either an intervention or a health education control condition in a parallel design. Both conditions consist of weekly group sessions with other PAD participants. In the intervention, cognitive behavioral techniques are used to assist participants in setting and adhering to home-based walking exercise goals. Participants are encouraged to walk for exercise at home at least 5 days/week. In the control condition, participants receive lectures on health-related topics. After 6 months of on-site weekly sessions, participants are transitioned to telephone follow-up for another 6 months. Participants in the intervention are asked to continue home walking exercise. The primary outcome is change in six-minute walk performance between baseline and six-month follow-up. Secondary outcomes include change in six-minute walk performance at 12-month follow-up, and change in treadmill walking performance, the Walking Impairment Questionnaire, quality of life, and physical activity at six and 12-month follow-up. In conclusion, if our group-mediated cognitive behavioral intervention is associated with improved walking performance in individuals with PAD, results will have major public health implications for the large and growing number of people with PAD.

Vitamin D status and functional performance in peripheral artery disease

The clinical implications of low vitamin D in peripheral artery disease (PAD) are unknown. We hypothesized that among individuals with PAD, lower levels of 25-hydroxyvitamin D would be associated with poorer functional performance, more adverse calf muscle characteristics, and poorer peripheral nerve function. Participants were 402 men and women with PAD who underwent measurement of 25-hydroxyvitamin D (DiaSorin radioimmunoassay) along with 6-minute walk testing, measurement of walking velocity at usual and fastest pace, computed tomography-measured calf muscle density, and peripheral nerve conduction velocity (NCV). Among PAD participants, 20.4% had 25-hydroxyvitamin D levels < 30 nmol/L, consistent with deficient vitamin D status. Adjusting for age, sex, and race, lower 25-hydroxyvitamin D levels were associated with poorer 6-minute walk performance (p trend = 0.002), slower usual-paced 4-meter walking velocity (p trend = 0.031), slower fast-paced 4-meter walking velocity (p trend = 0.043), and lower calf muscle density (p trend = 0.031). After additional adjustment for body mass index (BMI) and diabetes, none of these associations remained statistically significant. However, lower levels of 25-hydroxyvitamin D were associated with poorer peroneal NCV (p trend = 0.013) and poorer sural NCV (p trend = 0.039), even after adjusting for age, sex, race, BMI, comorbidities, smoking, physical activity, and other confounders. In conclusion, vitamin D deficiency is common among people with PAD encountered in clinical settings. After adjusting for BMI and diabetes mellitus, we found no significant associations of lower levels of 25-hydroxyvitamin D with poorer functional performance or calf muscle characteristics. Associations of low vitamin D levels with poorer peripheral nerve function require further study.

The Walking Impairment Questionnaire stair-climbing score predicts mortality in men and women with peripheral arterial disease

OBJECTIVE

The Walking Impairment Questionnaire (WIQ) measures self-reported walking distance, walking speed, and stair-climbing ability in men and women with lower extremity peripheral arterial disease (PAD). We determined whether poorer WIQ scores are associated with higher all-cause and cardiovascular disease (CVD) mortality in individuals with and without PAD.

METHODS

We identified 1048 men and women with and without PAD from Chicago-area medical centers. Participants completed the WIQ at baseline and were monitored for a median of 4.5 years. Cox proportional hazards models were used to relate baseline WIQ scores with death, adjusting for age, sex, race, the ankle-brachial index (ABI), comorbidities, and other covariates.

RESULTS

During follow-up, 461 participants (44.0%) died, including 158 deaths from CVD. PAD participants in the lowest baseline quartile of the WIQ stair-climbing scores had higher all-cause mortality (hazard ratio, 1.70; 95% confidence interval, 1.08-2.66, P = .02) and higher CVD mortality (hazard ratio, 3.11; 95% confidence interval, 1.30-7.47, P = .01) compared with those with the highest baseline WIQ stair-climbing score. Among PAD participants, there were no significant associations of lower baseline WIQ distance or speed scores with rates of all-cause mortality (P = .20 and P = .07 for trend, respectively) or CVD mortality (P = .51 and P = .33 for trend, respectively). Among non-PAD participants there were no significant associations of lower baseline WIQ stair-climbing, distance, or speed score with rates of all-cause mortality (P = .94, P = .69, and P = .26, for trend, respectively) or CVD mortality (P = .28, P = .68, and P = .78, for trend, respectively).

CONCLUSIONS

Among participants with PAD, lower WIQ stair-climbing scores are associated with higher all-cause and CVD mortality, independently of the ABI and other covariates.

Calf muscle characteristics, strength measures, and mortality in peripheral arterial disease: a longitudinal study

OBJECTIVES

This study analyzed whether lower calf muscle density and poorer upper and lower extremity strength are associated with higher mortality rates in men and women with peripheral arterial disease (PAD).

BACKGROUND

Men and women with lower extremity PAD have lower calf muscle density and reduced lower extremity strength compared with individuals without PAD.

METHODS

At baseline, participants underwent measurement of calf muscle density with computed tomography in addition to knee extension power and isometric knee extension, plantar flexion, and hand grip strength measures. Participants were followed up annually for up to 4 years. Results were adjusted for age, sex, race, body mass index, ankle-brachial index, smoking, physical activity, and comorbidities.

RESULTS

Among 434 PAD participants, 103 (24%) died during a mean follow-up of 47.6 months. Lower calf muscle density was associated with higher all-cause mortality (lowest density tertile hazard ratio [HR]: 1.80 [95% confidence interval (CI): 1.07 to 3.03], second tertile HR: 0.91 (95% CI: 0.51 to 1.62); highest density tertile HR: 1.00; p trend = 0.020) and higher cardiovascular disease mortality (lowest density tertile HR: 2.39 [95% CI: 0.90 to 6.30], second tertile HR: 0.85 [95% CI: 0.27 to 2.71]; highest density tertile HR: 1.00; p trend = 0.047). Poorer plantar flexion strength (p trend = 0.004), lower baseline leg power (p trend = 0.046), and poorer handgrip (p trend = 0.005) were associated with higher all-cause mortality.

CONCLUSIONS

These data demonstrate that lower calf muscle density and weaker plantar flexion strength, knee extension power, and hand grip were associated with increased mortality in these participants with PAD, independently of the ankle-brachial index and other confounders.

Clinical correlates of size and number of collateral vessels in peripheral artery disease

We studied associations of the number and size of magnetic resonance angiography (MRA)-assessed lower extremity collateral vessels with the ankle-brachial index (ABI), severity of superficial femoral artery (SFA) plaque, and leg symptoms in participants with peripheral artery disease (PAD). A total of 303 participants with PAD underwent time-resolved MRA at the thigh station. Collaterals were categorized by number (Category 1: 0-3 collaterals; Category 2: 4-7 collaterals; Category 3: ≥ 8 collateral vessels) and size (Grade 1: ≤ 5 small collaterals; Grade 2: > 5 small vessels; Grade 3: ≤ 5 large collaterals; Grade 4: > 5 large collaterals). Adjusting for age, sex, race, comorbidities and other covariates, more numerous collateral vessels were associated with lower ABI values (Category 1: 0.79; Category 2: 0.67; Category 3: 0.60; p trend < 0.001). Similarly, larger collateral vessels were associated with lower ABI values (Grade 1: 0.75; Grade 2: 0.65; Grade 3: 0.62; Grade 4: 0.59; p trend < 0.001). More numerous (p < 0.001) and larger (p < 0.001) collateral vessels were associated with greater mean SFA plaque area (p trend < 0.001). More numerous (p trend = 0.007) and larger (p trend = 0.017) collateral vessels were associated with a lower prevalence of asymptomatic PAD. In conclusion, among participants with PAD, larger and more numerous collaterals, measured by MRA, were associated with lower ABI values, greater plaque area in the SFA, and a lower prevalence of asymptomatic PAD. Further study is needed to determine the role of collateral vessels in maintaining functional performance in PAD.

Successful percutaneous revascularization of totally occluded left subclavian artery using orbital atherectomy

Subclavian artery steal (SAS) after coronary artery bypass graft (CABG) has been reported to be as high as 3.4%. These patients with patent left internal mammary artery (LIMA) anastomosis will also have coronary-subclavian steal syndrome (CSSS). Percutaneous intervention (PCI) by balloon angioplasty (BA) and stenting has been done successfully for subclavian artery (SA) stenosis. The visibility of the vertebral artery (VA) and LIMA during BA and stent positioning is extremely important. Debulking total occlusions by orbital atherectomy (OA) and avoiding unnecessary BA, stenting across side branches may decrease the chance of plaque shifting and subsequent loss of flow especially if they have ostial disease. Herein we report successful OA, BA and stenting of chronic total occlusion (CTO) of proximal left subclavian artery in a patient with coronary-subclavian steal syndrome with preservation of LIMA and diseased left vertebral artery (VA).

The difference in blood pressure readings between arms and survival: primary care cohort study

OBJECTIVE

To determine whether a difference in systolic blood pressure readings between arms can predict a reduced event free survival after 10 years.

DESIGN

Cohort study.

SETTING

Rural general practice in Devon, United Kingdom.

PARTICIPANTS

230 people receiving treatment for hypertension in primary care.

INTERVENTION

Bilateral blood pressure measurements recorded at three successive surgery attendances.

MAIN OUTCOME MEASURES

Cardiovascular events and deaths from all causes during a median follow-up of 9.8 years.

RESULTS

At recruitment 24% (55/230) of participants had a mean interarm difference in systolic blood pressure of 10 mm Hg or more and 9% (21/230) of 15 mm Hg or more; these differences were associated with an increased risk of all cause mortality (adjusted hazard ratio 3.6, 95% confidence interval 2.0 to 6.5 and 3.1, 1.6 to 6.0, respectively). The risk of death was also increased in 183 participants without pre-existing cardiovascular disease with an interarm difference in systolic blood pressure of 10 mm Hg or more or 15 mm Hg or more (2.6, 1.4 to 4.8 and 2.7, 1.3 to 5.4). An interarm difference in diastolic blood pressure of 10 mm Hg or more was weakly associated with an increased risk of cardiovascular events or death.

CONCLUSIONS

Differences in systolic blood pressure between arms can predict an increased risk of cardiovascular events and all cause mortality over 10 years in people with hypertension. This difference could be a valuable indicator of increased cardiovascular risk. Bilateral blood pressure measurements should become a routine part of cardiovascular assessment in primary care.

Association of a difference in systolic blood pressure between arms with vascular disease and mortality: a systematic review and meta-analysis

BACKGROUND

Differences in systolic blood pressure (SBP) of 10 mm Hg or more or 15 mm Hg or more between arms have been associated with peripheral vascular disease and attributed to subclavian stenosis. We investigated whether an association exists between this difference and central or peripheral vascular disease, and mortality.

METHODS

We searched Medline, Embase, Cumulative Index to Nursing and Allied Health Literature, Cochrane, and Medline In Process databases for studies published before July, 2011, showing differences in SBP between arms, with data for subclavian stenosis, peripheral vascular disease, cerebrovascular disease, cardiovascular disease, or survival. We used random effects meta-analysis to combine estimates of the association between differences in SBP between arms and each outcome.

FINDINGS

We identified 28 eligible studies for review, 20 of which were included in our meta-analyses. In five invasive studies using angiography, mean difference in SBP between arms was 36·9 mm Hg (95% CI 35·4-38·4) for proven subclavian stenosis (>50% occlusion), and a difference of 10 mm Hg or more was strongly associated with subclavian stenosis (risk ratio [RR] 8·8, 95% CI 3·6-21·2). In non-invasive studies, pooled findings showed that a difference of 15 mm Hg or more was associated with peripheral vascular disease (nine cohorts; RR 2·5, 95% CI 1·6-3·8; sensitivity 15%, 9-23; specificity 96%, 94-98); pre-existing cerebrovascular disease (five cohorts; RR 1·6, 1·1-2·4; sensitivity 8%, 2-26; specificity 93%, 86-97); and increased cardiovascular mortality (four cohorts; hazard ratio [HR] 1·7, 95% CI 1·1-2·5) and all-cause mortality (HR 1·6, 1·1-2·3). A difference of 10 mm Hg or higher was associated with peripheral vascular disease (five studies; RR 2·4, 1·5-3·9; sensitivity 32%, 23-41; specificity 91%, 86-94).

INTERPRETATION

A difference in SBP of 10 mm Hg or more, or of 15 mm Hg or more, between arms might help to identify patients who need further vascular assessment. A difference of 15 mm Hg or more could be a useful indicator of risk of vascular disease and death.

FUNDING

Royal College of General Practitioners, South West GP Trust, and Peninsula Collaboration for Leadership in Applied Health Research and Care.

Prevalence of cardiovascular disease in Gabon: a population study

BACKGROUND

Data supporting epidemiological transition from a predominant burden of infectious diseases to one of chronic diseases in Africa result mostly from hospital surveys.

AIM

To estimate the cardiovascular disease (CVD) burden in Gabon.

METHODS

The study was conducted in Ntoum (8765 inhabitants). All subjects aged greater or equal to 40 years were invited to participate. Participants were interviewed about CVD history and risk factors; they responded to questionnaires on claudication and angina and had a clinical examination, including lower limb pulse palpation and bilateral brachial pressure measurement. Subjects were considered to have CVD in case of history of CVD (coronary artery, cerebrovascular and peripheral arterial diseases), a positive questionnaire or an abnormal finding during clinical examination.

RESULTS

The study included 736 subjects (313 men; 423 women). Systolic hypertension was highly prevalent (up to 47.7% and 53.7% in men and women aged 50 to 60 years, respectively). Of the 382 patients with hypertension, 74 (19.4%) were treated and only 22 (5.8%) were considered to have controlled hypertension. Overall, CVD was identified in 98 (13.3%) cases. Overall and newly diagnosed CVD prevalence rates were 14.7% and 11.5% for men and 14.9% and 8.9% for women, respectively. The presence of CVD was associated with hypertension (hazard ratio [HR] 3.69, 95% confidence interval [CI] 2.21-6.16; P<0.0001). Hypertension was predictive of stroke (HR 4.57, 95% CI 1.26-16.50; P<0.05), peripheral artery disease (HR 2.03, 95% CI 1.03-4.00; P<0.05) and subclavian artery stenosis (HR 5.79, 95% CI 2.21-15.2; P<0.05).

CONCLUSIONS

Our findings provide strong evidence of ongoing epidemiological transition in Gabon, where CVD prevalence rates increase mainly with hypertension, affecting about one in six individuals aged over 40 years.

Higher body mass index is associated with more adverse changes in calf muscle characteristics in peripheral arterial disease

OBJECTIVE

This study investigated whether higher body mass index (BMI) is associated with more adverse lower extremity muscle characteristics at baseline and more adverse changes in muscle over time among participants with lower extremity peripheral arterial disease (PAD).

METHODS

This was a longitudinal, observational study of 425 men and women with PAD and 261 without PAD. Computed tomography was used to measure calf muscle characteristics at baseline and every 2 years. Knee extension isometric strength, power, and 6-minute walk distance were measured at baseline and annually. Baseline BMI (kg/m(2)) categories were ideal (20-25), overweight (>25-30), and obese (>30). Analyses adjust for age, race, sex, ankle brachial index, comorbidities, and other covariates.

RESULTS

At baseline, higher BMI among participants with PAD was associated with greater calf muscle area (ideal BMI: 5181 mm(2); overweight: 5513 mm(2); obese: 5695 mm(2); P = .0009 for trend), higher calf muscle percentage of fat (6.38%, 10.28%, 17.44%, respectively, P < .0001 for trend), lower calf muscle density (P < .0001 for trend), and higher isometric knee extension strength (P = .015 for trend). Among participants with PAD, higher BMI was associated with greater declines in calf muscle area (P = .030 for trend) and greater increases in calf muscle percentage of fat (P = .023 for trend). Among participants without PAD, there were no significant associations of baseline BMI with changes in lower extremity muscle outcomes over time.

CONCLUSIONS

Among PAD participants, higher BMI is associated with greater calf muscle area at baseline. However, higher BMI is associated with more adverse calf muscle density and calf muscle percentage of fat at baseline and greater declines in calf muscle area over time.

Superficial femoral artery plaque and functional performance in peripheral arterial disease: walking and leg circulation study (WALCS III)

OBJECTIVES

We studied associations of magnetic resonance imaging measurements of plaque area and relative percent lumen reduction in the proximal superficial femoral artery with functional performance among participants with peripheral arterial disease.

BACKGROUND

The clinical significance of directly imaged plaque characteristics in lower extremity arteries is not well established.

METHODS

A total of 454 participants with an ankle brachial index <1.00 underwent magnetic resonance cross-sectional imaging of the proximal superficial femoral artery and completed a 6-min walk test, measurement of 4-m walking velocity at usual and fastest pace, and measurement of physical activity with a vertical accelerometer.

RESULTS

Adjusting for age, sex, race, body mass index, smoking, statin use, comorbidities, and other covariates, higher mean plaque area (1st quintile [least plaque]: 394 m, 2nd quintile: 360 m, 3rd quintile: 359 m, 4th quintile: 329 m, 5th quintile [greatest plaque]: 311 m; p trend <0.001) and smaller mean percent lumen area (1st quintile [greatest plaque]: 319 m, 2nd quintile: 330 m, 3rd quintile: 364 m, 4th quintile: 350 m, 5th quintile: 390 m; p trend <0.001) were associated with shorter distance achieved in the 6-min walk test. Greater mean plaque area was also associated with slower usual-paced walking velocity (p trend = 0.006) and slower fastest-paced 4-m walking velocity (p trend = 0.003). Associations of mean plaque area and mean lumen area with 6-min walk distance remained statistically significant even after additional adjustment for the ankle brachial index and leg symptoms.

CONCLUSIONS

Among participants with peripheral arterial disease, greater plaque burden and smaller lumen area in the proximal superficial femoral artery are associated independently with poorer functional performance, even after adjusting for the ankle brachial index and leg symptoms.

Association of body mass index with peripheral arterial disease in older adults: the Cardiovascular Health Study

The authors hypothesized that the absence of cross-sectional associations of body mass index (BMI; weight (kg)/height (m)(2)) with peripheral arterial disease (PAD) in prior studies may reflect lower weight among persons who smoke or have poor health status. They conducted an observational study among 5,419 noninstitutionalized residents of 4 US communities aged ≥ 65 years at baseline (1989-1990 or 1992-1993). Ankle brachial index was measured, and participants reported their history of PAD procedures. Participants were followed longitudinally for adjudicated incident PAD events. At baseline, mean BMI was 26.6 (standard deviation, 4.6), and 776 participants (14%) had prevalent PAD. During 13.2 (median) years of follow-up through June 30, 2007, 276 incident PAD events occurred. In cross-sectional analysis, each 5-unit increase in BMI was inversely associated with PAD (prevalence ratio (PR) = 0.92, 95% confidence interval (CI): 0.85, 1.00). However, among persons in good health who had never smoked, the direction of association was opposite (PR = 1.20, 95% CI: 0.94, 1.52). Similar results were observed between BMI calculated using weight at age 50 years and PAD prevalence (PR = 1.30, 95% CI: 1.11, 1.51) and between BMI at baseline and incident PAD events occurring during follow-up (hazard ratio = 1.32, 95% CI: 1.00, 1.76) among never smokers in good health. Greater BMI is associated with PAD in older persons who remain healthy and have never smoked. Normal weight maintenance may decrease PAD incidence and associated comorbidity in older age.

Blood pressure measurement method and inter-arm differences: a meta-analysis

BACKGROUND

Screening for inter-arm difference (IAD) of blood pressure (BP) at each first visit is recommended by numerous guidelines whereas it is unclear whether the method by which IAD is measured has significant influence on the IAD value.

METHODS

A systematic review is made of the studies reporting on double-arm measurements and the association of IAD with procedure characteristics (Medline/PubMed, Embase, and Cochrane Library).

RESULTS

The mean absolute IAD was 5.4 ± 1.7 and 3.6 ± 1.2 mm Hg for systolic and diastolic BP, respectively. Of all subjects 14% had a systolic IAD ≥10 mm Hg, 4% a systolic IAD ≥20 mm Hg, and 7% a diastolic IAD ≥10 mm Hg. The relative risk (RR) of obtaining a systolic IAD ≥10 and 20 mm Hg and a diastolic IAD ≥10 mm Hg is higher when measuring sequentially instead of simultaneously (2.2 (95% CI: 1.4-3.6), P < 0.01; 4.8 (95% CI: 1.1-21.9), P < 0.05 and 2.5 (95% CI: 1.0-6.3) P < 0.05, respectively), when using a manual instead of an automated device (2.1 (95% CI: 1.1-3.9), P < 0.05; 4.4 (95% CI: 1.8-10.8), P < 0.01 and 3.7 (95% CI: 1.6-8.6), P < 0.01, respectively) and when performing only one BP measurement instead of multiple (2.0 (95% CI: 1.1-3.8), P < 0.05; 4.3 (95% CI: 1.6-11.4), P < 0.01 and 4.4 (95% CI: 1.7-11.4), P < 0.01, respectively).

CONCLUSION

Screening for IAD of BP is important but the measurement methodology has a major influence on IAD results. To prevent overestimation and observer bias IAD should be assessed simultaneously at both arms, with one or two automatic devices and multiple readings should be taken.

Angioplasty versus stenting for subclavian artery stenosis

BACKGROUND

There is insufficient evidence to guide stent usage following angioplasty in subclavian artery stenosis.

OBJECTIVES

The aim of this review was to determine whether stenting is more effective than angioplasty alone for stenosis of the subclavian artery.

SEARCH STRATEGY

The Cochrane Peripheral Vascular Diseases Group searched their Specialised Register (last searched August 2011) and the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 3). In addition, the authors searched the MEDLINE, EMBASE and LILACS databases, and handsearched relevant journals. Informal enquiries were made with the major stent device manufacturers to obtain information on unpublished data and any ongoing trials. There was no restriction on language.

SELECTION CRITERIA

Randomized controlled trials of endovascular treatment of subclavian artery lesions comparing angioplasty alone and stent implantation.

DATA COLLECTION AND ANALYSIS

Two authors independently evaluated studies to assess eligibility. Discrepancies were resolved by discussion. If there was no agreement, the third author was asked to assess the study for inclusion.

MAIN RESULTS

To date we have not identified any completed or ongoing randomized controlled trials comparing percutaneous transluminal angioplasty and stenting for subclavian artery stenosis.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to determine whether stenting is more effective than angioplasty alone for stenosis of the subclavian artery.

Subclavian artery stenosis as a cause of acute coronary syndrome in a patient after coronary artery bypass grafting

We described a case of a 74-year-old man who suffered from acute coronary syndrome 7 years after coronary artery bypass grafting. The patient underwent angioplasty of the obtuse marginal branch of the left coronary artery from venous graft access, which did not result in relief of ailments. Only angioplasty of the narrowed subclavian artery caused an improvement in the patient's condition. The clinical significance of narrowing within the subclavian artery in patients after the procedure of implanting the left subclavian artery into the coronary artery system was discussed.

Poorer clock draw test scores are associated with greater functional impairment in peripheral artery disease: the Walking and Leg Circulation Study II

We hypothesized that, in the absence of clinically recognized dementia, cognitive dysfunction measured by the clock draw test (CDT) is associated with greater functional impairment in men and women with peripheral artery disease (PAD). Participants were men and women aged 60 years and older with Mini-Mental Status Examination scores ≥ 24 with PAD (n = 335) and without PAD (n = 234). We evaluated the 6-minute walk test, 4-meter walking velocity at usual and fastest pace, the Short Physical Performance Battery (SPPB), and accelerometer-measured physical activity. CDTs were scored using the Shulman system as follows: Category 1 (worst): CDT score 0-2; Category 2: CDT score 3; Category 3 (best): CDT score 4-5. Results were adjusted for age, sex, race, education, ankle-brachial index (ABI), and comorbidities. In individuals with PAD, lower CDT scores were associated with slower 4-meter usual-paced walking velocity (Category 1: 0.78 meters/second; Category 2: 0.83 meters/second; Category 3: 0.86 meters/second; p-trend = 0.025) and lower physical activity (Category 1: 420 activity units; Category 2: 677 activity units; Category 3: 701 activity units; p-trend = 0.045). Poorer CDT scores were also associated with worse functional performance in individuals without PAD (usual and fast-paced walking velocity and SPPB, p-trend = 0.022, 0.043, and 0.031, respectively). In conclusion, cognitive impairment identified with CDT is independently associated with greater functional impairment in older, dementia-free individuals with and without PAD. Longitudinal studies are necessary to explore whether baseline CDT scores and changes in CDT scores over time can predict long-term decline in functional performance in individuals with and without PAD.

Family history of peripheral artery disease is associated with prevalence and severity of peripheral artery disease: the San Diego population study

OBJECTIVES

The purpose of this study was to determine the association of family history of peripheral artery disease (PAD) with PAD prevalence and severity.

BACKGROUND

PAD is a significant public health problem. Shared genetic and environmental factors may play an important role in the development of PAD. However, family history of PAD has not been investigated adequately.

METHODS

The San Diego Population Study enrolled 2,404 ethnically diverse men and women 29 to 91 years of age who attended a baseline visit from 1994 through 1998 to assess PAD and venous disease. Ankle brachial index measurement was performed at the baseline clinic examination, and family history of PAD was obtained via questionnaire. Family history of PAD was defined primarily as having any first-degree relative with PAD. Prevalent PAD was defined as ankle brachial index ≤ 0.90, and severe prevalent PAD was defined as ankle brachial index ≤ 0.70, with both definitions also including any previous leg revascularization. Logistic regression was used to evaluate the association of family history of PAD with prevalent PAD.

RESULTS

The mean age was 59 ± 11 years, 66% were women, and 58% were Caucasian, with 42% representing other racial or ethnic groups. Prevalence of PAD was 3.6%, and severe prevalent PAD was 1.9%. In fully adjusted models, family history of PAD was associated with a 1.83-fold higher odds of PAD (95% confidence interval: 1.03 to 3.26, p = 0.04), an association that was stronger for severe prevalent PAD (odds ratio: 2.42, 95% confidence interval: 1.13 to 5.23, p = 0.02).

CONCLUSIONS

Family history of PAD is independently strongly associated with PAD prevalence and severity. This indicates a role for genetic factors or other shared environmental factors, or both, contributing to PAD.

Lower extremity nerve function, calf skeletal muscle characteristics, and functional performance in peripheral arterial disease

OBJECTIVES

To determine whether poor lower extremity nerve function is associated with less-favorable calf muscle characteristics and greater functional impairment in people with and without peripheral arterial disease (PAD).

DESIGN

Cross-sectional.

SETTING

Three Chicago-area medical centers.

PARTICIPANTS

Four hundred thirteen participants with PAD (ankle-brachial index (ABI) < 0.90) and 255 without.

MEASUREMENTS

Electrodiagnostic testing of the peroneal nerve was performed. Calf muscle cross-sectional area and percentage fat were measured using computed tomography at 66.7% of the distance between the distal and proximal tibia. Six-minute walk performance was measured.

RESULTS

Adjusting for age, sex, race, ABI, leg symptoms, smoking, physical activity, comorbidities, and other covariates, lower peroneal nerve conduction velocity (NCV) was associated with lower calf muscle area (first quartile 4,770.3 mm(2) , fourth quartile 5,571 mm(2) , P < .001) and poorer 6-minute walk distance (first quartile 989.2 feet, fourth quartile 1,210.8 feet, P < .001) in participants without diabetes mellitus with PAD. Lower peroneal NCV was associated with lower calf muscle area (first quartile 5,166.0 mm(2) , fourth quartile 6,003.8 mm(2) , P = .01) and poorer 6-minute walk distance (first quartile 866.4 feet, fourth quartile 1,082.5 feet, P = .01) in participants with diabetes mellitus and PAD as well. In participants without PAD, lower peroneal NCV was not associated with lower calf muscle area but was associated with poorer 6-minute walk distance only in participants without diabetes mellitus (first quartile 1,317.0 feet, fourth quartile 1,570.4 feet, P-trend < .001).

CONCLUSION

Lower peroneal nerve function is associated with smaller calf muscle area and greater functional impairment in individuals with PAD. Future study is needed to determine whether improving peroneal NCV prevents loss of calf muscle and functional decline in people with PAD.

Associations of calf skeletal muscle characteristics and peripheral nerve function with self-perceived physical functioning and walking ability in persons with peripheral artery disease

We determined whether more adverse calf muscle characteristics and poorer peripheral nerve function were associated with impairments in self-perceived physical functioning and walking ability in persons with lower extremity peripheral artery disease (PAD). Participants included 462 persons with PAD; measures included the ankle-brachial index (ABI), medical history, electrophysiologic characteristics of nerves, and computed tomography of calf muscle. Self-perceived physical functioning and walking ability were assessed using the 36-Item Short Form Health Survey (SF-36) and the Walking Impairment Questionnaire (WIQ). Results were adjusted for age, sex, race, ABI, body mass index, comorbidities, and other confounders. Lower calf muscle area was associated with a poorer SF-36 physical function (PF) score (overall p-trend < 0.001, 33.76 PF score for the lowest quartile versus 59.74 for the highest, pairwise p < 0.001) and a poorer WIQ walking distance score (p-trend = 0.001, 29.71 WIQ score for the lowest quartile versus 48.43 for the highest, pairwise p < 0.001). Higher calf muscle percent fat was associated with a poorer SF-36 PF score (p-trend < 0.001, 53.76 PF score for the lowest quartile versus 40.28 for the highest, pairwise p = 0.009). Slower peroneal nerve conduction velocity was associated with a poorer WIQ speed score ( p-trend = 0.023, 30.49 WIQ score for the lowest quartile versus 40.48 for the highest, pairwise p = 0.031). In summary, adverse calf muscle characteristics and poorer peripheral nerve function are associated significantly and independently with impairments in self-perceived physical functioning and walking ability in PAD persons.

Greater sedentary hours and slower walking speed outside the home predict faster declines in functioning and adverse calf muscle changes in peripheral arterial disease

OBJECTIVES

In participants with peripheral arterial disease (PAD), we determined whether more sedentary behavior and slower outdoor walking speed were associated with faster functional decline and more adverse changes in calf muscle characteristics over time.

BACKGROUND

Modifiable behaviors associated with faster functional decline in lower-extremity PAD are understudied.

METHODS

Participants were 384 men and women with an ankle brachial index <0.90 followed for a median of 47 months. At baseline, participants reported the number of hours they spent sitting per day and their walking speeds outside their homes. Participants underwent baseline and annual measures of objective functional performance. Calf muscle characteristics were measured with computed tomography at baseline and every 2 years subsequently. Analyses were adjusted for age, sex, race, comorbidities, ankle brachial index, and other confounders.

RESULTS

Slower walking speed outside the home was associated with faster annual decline in calf muscle density (brisk/striding pace -0.32 g/cm(3), average pace -0.46 g/cm(3), casual strolling -1.03 g/cm(3), no walking at all -1.43 g/cm(3), p trend <0.001). Greater hours sitting per day were associated with faster decline in 6-min walk (<4 h: -35.8 feet/year; 4 to <7 h: -41.1 feet/year; 8 to <11 h: -68.7 feet; ≥12 h: -78.0 feet; p trend = 0.008). Similar associations were observed for greater hours sitting per day and faster declines in fast-paced (p trend = 0.018) and usual-paced (p trend < 0.001) 4-m walking velocity.

CONCLUSIONS

Greater sedentary hours per day and slower outdoor walking speed are modifiable behaviors that are associated with faster functional decline and greater decline in calf muscle density, respectively, in patients with PAD.