ACC/AHA 2005 Practice Guidelines for the management of patients with peripheral arterial disease (lower extremity, renal, mesenteric, and abdominal aortic): a collaborative report from the American Association for Vascular Surgery/Society for Vascular Surgery, Society for Cardiovascular Angiography and Interventions, Society for Vascular Medicine and Biology, Society of Interventional Radiology, and the ACC/AHA Task Force on Practice Guidelines (Writing Committee to Develop Guidelines for the Management of Patients With Peripheral Arterial Disease): endorsed by the American Association of Cardiovascular and Pulmonary Rehabilitation; National Heart, Lung, and Blood Institute; Society for Vascular Nursing; TransAtlantic Inter-Society Consensus; and Vascular Disease Foundation

Commentary: Shoot the renals!

Atherosclerotic renal artery stenosis (ARAS) is a growing dilemma. The condition is increasingly common and can promulgate hypertension and result in renal failure. However, patients with ARAS generally die owing to their coronaries or cerebral vessels. Intervention, by stenting or angioplasty is beloved and believed, but not proved. The American Heart Association has recently published guidelines regarding patients at high risk for ARAS who are potential candidates for revascularisation. Since this phraseology includes practically every patient with atherosclerosis, these guidelines appear ill advised.

Cardiovascular risk factors and signs of subclinical atherosclerosis in the Heinz Nixdorf Recall Study

INTRODUCTION

Modern investigation modalities allow markers of atherosclerosis to be detected at a subclinical stage. The aim of the study was to analyze the prevalence of these markers in relation to traditional risk factors.

METHODS

The population based study included 4814 participants, aged 45 to 75 years, with a response rate of 55.8% of those contacted. The patients' history, psychosocial and environmental risk factors were assessed.

RESULTS

The prevalence of obesity was 26.2% in men and 28.1% in women, 26% of men and 21% of women were smokers. Hypertension was found in 46% of men and 31% of women, diabetes in 9.3% of men and 6.3% of women. Markers of subclinical peripheral arterial disease were found in 6.4% of men and 5.1% of women, of subclinical carotid artery disease in 43.2% and 30.7%, and of subclinical coronary artery calcification in 82.3% and 55.2%, respectively. The prevalence of coronary calcification measured using an Agatston Score >100 was in 40% in men and 15% in women, using a score >400, 16.8% and 4.5%, respectively.

DISCUSSION

A high prevalence of subclinical atherosclerosis was found in the older population. The follow-up period will demonstrate whether the detection of markers of subclinical atherosclerosis will improve risk stratification beyond that offered by traditional risk factors.

Serum Total Bilirubin Level and Prevalent Lower-Extremity Peripheral Arterial Disease

Background— Bilirubin, with recently recognized antioxidant and antiinflammatory activity, has emerged as a candidate for atheroprotection. We hypothesized that higher levels of bilirubin would reduce susceptibility to peripheral arterial disease (PAD).

Methods and Results— We analyzed 7075 adults with data available on the ankle brachial index, serum total bilirubin level, and PAD risk factors in the National Health and Nutrition Examination Survey (1999 to 2004), a nationally representative cross-sectional examination of the United States population. A 0.1 mg/dL increase in bilirubin level was associated with a 6% reduction in the odds of PAD (OR 0.94 [95% CI 0.90 to 0.98]) after adjustment for age, gender, race/ethnicity, smoking status, diabetes, hypertension, hypercholesterolemia, chronic kidney disease, CRP, and homocysteine. This result was not dependent on bilirubin levels above the reference range, liver disease, or alcohol intake. The inverse association of bilirubin with PAD tended to be stronger among men (OR 0.90 [95% CI 0.85 to 0.96]) compared with women (OR 0.97 [95% CI 0.91 to 1.04]; P interaction =0.05), and was stronger among active smokers (OR 0.81 [95% CI 0.73 to 0.90]) compared with nonsmokers (OR 0.97 [95% CI 0.93 to 1.02]; P interaction <0.01).

Conclusions— Increased serum total bilirubin level is associated with reduced PAD prevalence. This result is consistent with the hypothesis that bilirubin is protective from PAD.

Metabolic syndrome and incident end-stage peripheral vascular disease: a 14-year follow-up study in elderly Finns

OBJECTIVE

We investigated the relationship of the metabolic syndrome and its single components, defined by four different criteria, with peripheral vascular disease (PVD) in a prospective population-based study.

RESEARCH DESIGN AND METHODS

The metabolic syndrome was defined according to the World Health Organization (WHO), the National Cholesterol Education Program (NCEP), the International Diabetes Federation (IDF), and the American Heart Association (updated NCEP) criteria. We investigated the relationship of the metabolic syndrome defined by the aforementioned four criteria with PVD (revacularization and amputation) by Cox regression analyses in a Finnish population of 1,212 subjects, aged 65-74 years, with and without diabetes during a 14-year follow-up.

RESULTS

The metabolic syndrome defined by the WHO, NCEP, and updated NCEP criteria was associated with a statistically significant risk for incident PVD (n = 57) with adjustment for all confounding variables except for prevalent diabetes (hazard ratios [HRs] from 1.91 to 2.62). After adjustment for prevalent diabetes or after the exclusion of subjects with prevalent diabetes, there was no association between the metabolic syndrome by any criteria and incident PVD. Of the single components of the metabolic syndrome, elevated fasting glucose by the WHO and NCEP criteria (HR 2.35) and microalbuminuria by the WHO definition (2.56) predicted PVD in multivariable models (prevalent diabetes included).

CONCLUSIONS

The metabolic syndrome defined by the WHO, NCEP, and updated NCEP criteria predicted incident end-stage PVD in elderly Finns but only when not adjusted for diabetes status. Two of the single components of the metabolic syndrome, elevated fasting plasma glucose and microalbuminuria, predicted PVD. We conclude that the metabolic syndrome predicts PVD but not above and beyond the risk associated with diabetes and microalbuminuria.

European guidelines on cardiovascular disease prevention in clinical practice: executive summary. Fourth Joint Task Force of the European Society of Cardiology and other societies on cardiovascular disease prevention in clinical practice (constituted by representatives of nine societies and by invited experts)

Other experts who contributed to parts of the guidelines: Edmond Walma, Schoonhoven (The Netherlands), Tony Fitzgerald, Dublin (Ireland), Marie Therese Cooney, Dublin (Ireland), Alexandra Dudina, Dublin (Ireland) European Society of Cardiology (ESC) Committee for Practice Guidelines (CPG):, Alec Vahanian (Chairperson) (France), John Camm (UK), Raffaele De Caterina (Italy), Veronica Dean (France), Kenneth Dickstein (Norway), Christian Funck-Brentano (France), Gerasimos Filippatos (Greece), Irene Hellemans (The Netherlands), Steen Dalby Kristensen (Denmark), Keith McGregor (France), Udo Sechtem (Germany), Sigmund Silber (Germany), Michal Tendera (Poland), Petr Widimsky (Czech Republic), José Luis Zamorano (Spain)

Document reviewers: Irene Hellemans (CPG Review Coordinator) (The Netherlands), Attila Altiner (Germany), Enzo Bonora (Italy), Paul N. Durrington (UK), Robert Fagard (Belgium), Simona Giampaoli(Italy), Harry Hemingway (UK), Jan Hakansson (Sweden), Sverre Erik Kjeldsen (Norway), Mogens Lytken Larsen (Denmark), Giuseppe Mancia (Italy), Athanasios J. Manolis (Greece), Kristina Orth-Gomer (Sweden), Terje Pedersen (Norway), Mike Rayner (UK), Lars Ryden (Sweden), Mario Sammut (Malta), Neil Schneiderman (USA), Anton F. Stalenhoef (The Netherlands), Lale Tokgözoglu (Turkey), Olov Wiklund (Sweden), Antonis Zampelas (Greece)

Patients at high risk for ischemic stroke: identification and actions

Atherosclerosis is a disease of chronic inflammation. It is diffuse, multisystemic and affects the vascular, metabolic and immune systems. The traditional evaluation of risk is based on methods of clinical and biological assessments, and conventional imaging. The existence of symptomatic disease and the number of symptomatic sites of atherothrombosis are critical factors in predicting the recurrence of major vascular events. However, these methods are insufficient to predict near-future episodes, above all in the individual standard clinical practice. Active treatment of modifiable risk factors such as hypertension, dyslipidemia and atrial fibrillation can reduce the number of patients who develop a stroke. There is considerable evidence suggesting that a substantial proportion of the population with high blood pressure receives insufficient treatment. More active treatment of this condition is probably the most efficient single measure. Lifestyle factors such as smoking, diet, physical inactivity and obesity contribute to the relatively high incidence of stroke. There is a need to incorporate new systemic markers and new investigation techniques in the future so as to identify the individuals at risk in the population and to administer more individualized intervention therapies.

Gaps in Public Knowledge of Peripheral Arterial Disease

BACKGROUND

Lower-extremity peripheral arterial disease (PAD) is associated with decreased functional status, diminished quality of life, amputation, myocardial infarction, stroke, and death. Nevertheless, public knowledge of PAD as a morbid and mortal disease has not been previously assessed.

METHODS AND RESULTS

We performed a cross-sectional, population-based telephone survey of a nationally representative sample of 2501 adults > or = 50 years of age, with oversampling of blacks and Hispanics. The survey instrument measured the demographic, risk factor, and cardiovascular disease characteristics of the study population; prevalent leg symptoms; PAD awareness relative to atherosclerosis risk factors and other cardiovascular and noncardiovascular diseases; perceived causes of PAD; and perceived systemic and limb consequences of PAD. Respondents were 67.2+/-12.6 years of age with a high prevalence of risk factors but only a modest burden of known coronary or cerebrovascular disease. Twenty-six percent of respondents expressed familiarity with PAD, a rate significantly lower than that for any other cardiovascular disease or atherosclerosis risk factor. Within the "PAD-aware" cohort, knowledge was poor. Half of these individuals were not aware that diabetes and smoking increase the risk for PAD; 1 in 4 knew that PAD is associated with increased risk of heart attack and stroke; and only 14% were aware that PAD could lead to amputation. All knowledge domains were lower in individuals with lower income and education levels.

CONCLUSIONS

The public is poorly informed about PAD, with major knowledge gaps regarding the definition of PAD, risk factors that lead to PAD, and associated limb symptoms and amputation risk. The public is not aware that PAD imposes a high short-term risk of heart attack, stroke, and death. For the national cardiovascular disease burden to be reduced, public PAD knowledge could be improved by national PAD public education programs designed to reduce critical knowledge gaps.

Análise de fatores associados à ulceração de extremidades em indivíduos diabéticos com neuropatia periférica

A neuropatia periférica é o principal fator de risco para ulceração em pé de indivíduos diabéticos. Este estudo testou a associação de doença arterial periférica (DAP) à ulceração do pé em amostra de pacientes com neuropatia sensório-motora simétrica distal e se marcadores inflamatórios subclínicos também se associariam a esse evento. Foram avaliados 32 indivíduos diabéticos tipo 2 com exame do monofilamento de 10 g alterado, estratificados em 2 grupos segundo a história ou presença de úlcera nas extremidades inferiores. O grupo "com úlcera" (n = 18) incluiu aqueles que apresentavam úlcera ativa ou cicatrizada, ou que tiveram alguma amputação em membro inferior decorrente de complicações da úlcera. Além do exame neurológico e monofilamento, foram submetidos a bioestesiometria, avaliação vascular com Doppler e exames laboratoriais. Os grupos foram semelhantes quanto à distribuição dos sexos, média de idade e tempo de diabetes. O grupo com úlcera apresentou valores médios de altura (1,70 ± 0,06 vs. 1,63 ± 0,11 m; p = 0,044) e limiar de percepção vibratória no maléolo medial (40,9 ± 13,0 vs. 30,6 ± 12,3 V; p = 0,040) mais elevados que o sem a úlcera. Os grupos não diferiram entre si quanto à média dos marcadores inflamatórios. A resposta do reflexo patelar foi também pior no grupo com úlcera (p = 0,047), no qual se observou maior proporção de indivíduos com o índice hálux-braquial alterado (p = 0,030) quando comparado ao sem úlcera. Conclui-se que a DAP está associada à presença de úlcera (atual ou pregressa) em membros inferiores de indivíduos diabéticos neuropatas. A pesquisa de alteração de fluxo de artérias digitais de membro inferior (no hálux) contribuiu para detectar tal associação. Associação de neuropatia ulcerada a marcadores inflamatórios não foi observada, não sendo possível excluí-la devido às limitações do tamanho da amostra. Estudos prospectivos deverão examinar a sensibilidade do índice hálux-braquial para identificar DAP em indivíduos diabéticos sob risco de ulceração.

How to treat hypertension in patients with peripheral artery disease

The risk of peripheral artery disease is underestimated by many physicians; such risk is further augmented by the presence of hypertension. Detection of these conditions is essential to prevent cardiovascular accidents. This review deals with the management of peripheral artery disease as a risk factor, highlighting the need for triple therapy (antiplatelet drugs, angiotensin-converting enzyme inhibitors, and statins). Treatment of hypertension is approached by reviewing the essentials of the different antihypertensive drugs available, focusing on their peripheral circulatory effect. However, because individual antihypertensive drugs seem not to differ largely in this respect, attention is drawn to the message that the most important task in these patients is to control total cardiovascular risk rather than focusing on the choice of the individual antihypertensive drug.

Diabetic foot disease in the elderly

Elderly diabetic patients are particularly burdened by foot disease. The main causes for foot disease are peripheral neuropathy, foot deformities and peripheral arterial disease (PAD). Other risk factors include poor vision, gait abnormalities, reduced mobility an medical co-morbidities. The risk of major amputations increases with age, along with the increased prevalence of these risk factors. Th true risk of amputation and other burdens of foot disease in the elderly are likely underestimated by current epidemiological data. Th prevalence of neuropathy, foot deformities and PAD as well as the risk of amputation all increase with age even in non-diabetic patients. The principles of prevention and management of diabetic foot disease may also apply to large segments of the elderly non-diabetic population. Foot ulcer prevention relies on the identification of high risk patients and avoidance of triggering events, such as ill-fitting shoes, walking barefoot or poor self-care. PAD is a major cause of amputation and should be prevented by lifelong attention to glycaemic control, treatment of hypertension and dyslipidemia, and avoidance of smoking. The treatment of foot ulcers relies on pressure relief (off-loading), wound debridement, and treatment of infection and ischemia. It requires an individualized approach considering the patient's co-morbidities and functional status. Off-loading remains essential, but devices such as total contact casts or crutches can only rarely be implemented. However, providing adapted standard foot-wear and insisting on its consistent use even at home is often effective. The benefits of aggressive vascular or orthopaedic surgery should be weighed against the risks of prolonged hospitalisation and resulting functional decline. Greater attention to prevention and individualized care are needed to reduce the burden of diabetic foot disease in the elderly.

Role of image-guided vascular intervention in therapeutic angiogenesis translational research

Therapeutic angiogenesis, the process of growing collateral blood vessels to better perfuse ischemic tissue, has been hailed as an up-and-coming treatment for symptomatic lower-extremity peripheral arterial occlusive disease. A minimally invasive durable treatment would be welcome since current treatment options for this disease carry high risk, limited efficacy or limited durability. Unfortunately, as evidenced by disappointing results in multiple clinical trials, therapeutic angiogenesis has yet to deliver in humans the success it has seen in animal models. In this review, we discuss the challenges of translating therapeutic angiogenesis into effective clinical treatments for lower-extremity peripheral arterial occlusive disease and we highlight the role that experts in image-guided vascular interventions can play in advancing the field.

Low Serum Testosterone and High Serum Estradiol Associate With Lower Extremity Peripheral Arterial Disease in Elderly Men

OBJECTIVES

This study sought to determine whether serum levels of testosterone and estradiol associate with lower extremity peripheral arterial disease (PAD) in a large population-based cohort of elderly men.

BACKGROUND

Few studies have explored the relationship between serum sex steroids and lower extremity PAD in men.

METHODS

The Swedish arm of the MrOS (Osteoporotic Fractures in Men) study (n = 3,014; average age 75.4 years) assessed ankle-brachial index (ABI) and defined lower extremity PAD as ABI <0.90. Radioimmunoassay measured serum levels of total testosterone, estradiol, and sex hormone-binding globulin, and we calculated free testosterone and free estradiol levels from the mass action equations.

RESULTS

A linear regression model including age, current smoking, previous smoking, diabetes, hypertension, body mass index, free testosterone, and free estradiol showed that free testosterone independently and positively associates with ABI (p < 0.001), whereas free estradiol independently and negatively associates with ABI (p < 0.001). Logistic regression analyses showed that free testosterone in the lowest quartile (vs. quartiles 2 to 4; odds ratio [OR] 1.65, 95% confidence interval [CI] 1.22 to 2.23, p = 0.001) and free estradiol in the highest quartile (vs. quartiles 1 to 3; OR 1.45, 95% CI 1.09 to 1.94, p = 0.012) independently associate with lower extremity PAD.

CONCLUSIONS

This cross-sectional study shows for the first time that low serum testosterone and high serum estradiol levels associate with lower extremity PAD in elderly men. Future prospective and interventional studies are needed to establish possible causal relationships between sex steroids and the development of lower extremity PAD in men.

Predictive value of reactive hyperemia for cardiovascular events in patients with peripheral arterial disease undergoing vascular surgery

OBJECTIVE

Reactive hyperemia is the compensatory increase in blood flow that occurs after a period of tissue ischemia, and this response is blunted in patients with cardiovascular risk factors. The predictive value of reactive hyperemia for cardiovascular events in patients with atherosclerosis and the relative importance of reactive hyperemia compared with other measures of vascular function have not been previously studied.

METHODS AND RESULTS

We prospectively measured reactive hyperemia and brachial artery flow-mediated dilation by ultrasound in 267 patients with peripheral arterial disease referred for vascular surgery (age 66+/-11 years, 26% female). Median follow-up was 309 days (range 1 to 730 days). Fifty patients (19%) had an event, including cardiac death (15), myocardial infarction (18), unstable angina (8), congestive heart failure (6), and nonhemorrhagic stroke (3). Patients with an event were older and had lower hyperemic flow velocity (75+/-39 versus 95+/-50 cm/s, P=0.009). Patients with an event also had lower flow-mediated dilation (4.5+/-3.0 versus 6.9+/-4.6%, P<0.001), and when these 2 measures of vascular function were included in the same Cox proportional hazards model, lower hyperemic flow (OR 2.7, 95% CI 1.2 to 5.9, P=0.018) and lower flow-mediated dilation (OR 4.2, 95% CI: 1.8 to 9.8, P=0.001) both predicted cardiovascular events while adjusting for other risk factors.

CONCLUSIONS

Thus, lower reactive hyperemia is associated with increased cardiovascular risk in patients with peripheral arterial disease. Furthermore, flow-mediated dilation and reactive hyperemia incrementally relate to cardiovascular risk, although impaired flow-mediated dilation was the stronger predictor in this population. These findings further support the clinical relevance of vascular function measured in the microvasculature and conduit arteries in the upper extremity.

No influence of increased intake of orange and blackcurrant juices and dietary amounts of vitamin E on paraoxonase-1 activity in patients with peripheral arterial disease

BACKGROUND

Paraoxonase-1 (PON1) is an antioxidative enzyme associated with HDL and its serum activity is associated with risk of cardiovascular disease. The interindividual variation in PON1 activity is partly determined by genetic factors, such as polymorphisms in the PON1 gene, but also by dietary factors like the antioxidants.

AIM OF THE STUDY

We examined the effect of antioxidant-rich orange and blackcurrant juices and vitamin E supplement on PON1 activity in patients with peripheral arterial disease. Furthermore, we studied whether genetic polymorphisms in the PON1 gene predicted the change in PON1 activity.

METHODS

The study was designed as a cross-over trial with 48 participants who received two of the four possible treatments: (1) 250 ml orange juice and 250 ml blackcurrant juice; (2) 15 mg vitamin E; (3) 250 ml orange juice and 250 ml blackcurrant juice and 15 mg vitamin E; or (4) control/placebo (energy-equivalent sugar-containing beverage). The treatments were given for 28 days, separated by a 4-week wash-out period.

RESULTS

The PON1 activity was not affected by juice or vitamin E supplement neither was there evidence of synergetic effects. However, a statistically significant interaction was observed between treatment and PON1 genotype, such that PON1 activity increased after juice alone in patients carrying the PON1 L55-allele. Results need to be interpreted with care since the study population was relatively small.

CONCLUSION

Consumption of orange and blackcurrant juice and vitamin E supplement does not affect the activity of PON1 in patients with peripheral arterial disease. However, a gene-diet interaction may be present.

Baseline functional performance predicts the rate of mobility loss in persons with peripheral arterial disease

OBJECTIVES

We compared rates of mobility loss among persons with versus without peripheral arterial disease (PAD). Associations between baseline functional performance and mobility loss in persons with and without PAD were studied.

BACKGROUND

Persons with PAD have poorer functional performance than persons without PAD. The prognostic value of poorer performance in persons with PAD is unknown.

METHODS

Participants were 398 persons with and 240 without PAD who were free of mobility impairment at baseline. Participants were followed for a median of 50 months. Baseline measures included the 6-min walk and the Short Physical Performance Battery score. Mobility status, assessed annually, was defined as the self-reported loss of the ability to walk one-quarter mile or walk up and down one flight of stairs without assistance.

RESULTS

Adjusting for age and gender, we found that PAD participants had a greater rate of mobility loss than persons without PAD (hazard ratio [HR] 1.63; 95% confidence interval [CI] 1.03 to 2.56). This difference was not statistically significant after additional adjustment for baseline performance. Among PAD participants, risk of mobility loss in the lowest versus the 2 highest quartiles of baseline performance were as follows: HR 9.65 (95% CI 3.35 to 27.77, p < 0.001) for the 6-min walk and HR 12.84 (95% CI 4.64 to 35.55, p < 0.001) for the Short Physical Performance Battery when adjusting for confounders.

CONCLUSIONS

Persons with PAD experience greater mobility loss than persons without PAD. This association was explained by poorer baseline functional performance among participants with PAD. Poorer lower extremity performance predicts increased mobility loss in persons with and without PAD.

Systemic Risk Score Evaluation in Ischemic Stroke Patients (SCALA)

BACKGROUND AND PURPOSE

Stratification of patients with transient ischemic attack (TIA) or ischemic stroke (IS) by risk of recurrent stroke can contribute to optimized secondary prevention. We therefore aimed to assess cardiovascular risk factor profiles of consecutive patients hospitalized with TIA/IS to stratify the risk of recurrent stroke according to the Essen Stroke Risk Score (ESRS) and of future cardiovascular events according to the ankle brachial index (ABI) as a marker of generalized atherosclerosis

METHODS

In this cross-sectional observational study, 85 neurological stroke units throughout Germany documented cardiovascular risk factor profiles of 10 consecutive TIA/IS patients on standardized questionnaires. Screening for PAD was done with Doppler ultrasonography to calculate the ABI.

RESULTS

A total of 852 patients (57% men) with a mean age of 67+/-12.4 years were included of whom 82.9 % had IS. The median National Institutes of Health stroke sum score was 4 (TIA: 1). Arterial hypertension was reported in 71%, diabetes mellitus in 26%, clinical PAD in 10%, and an ABI < or = 0.9 in 51%. An ESRS > or = 3 was observed in 58%, which in two previous retrospective analyses corresponded to a recurrent stroke risk of > or = 4%/year. The correlation between the ESRS and the ABI was low (r = 0.21).

CONCLUSION

A high proportion of patients had asymptomatic atherosclerotic disease and a considerable risk of recurrent stroke according to the ABI and ESRS category. The prognostic accuracy as well as the potential benefit of various risk stratification scores in secondary stroke prevention require validation in a larger prospective study.

Prognostic Significance of Declining Ankle-brachial Index Values in Patients with Suspected or Known Peripheral Arterial Disease

BACKGROUND

Peripheral arterial disease (PAD) is a risk factor for cardiovascular events. This study assessed the prognostic significance of repeated ankle-brachial index (ABI) measurements at rest and after exercise in patients with PAD receiving conservative treatment.

METHODS

In a cohort study of 606 patients (mean age 62+/-12 years, 68% male), ABI at rest and after exercise was measured at baseline and after 1 year. Patients with reductions in ABI were divided into three equally-sized groups (minor, intermediate and major reductions) and were compared to patients without reductions. During a mean follow-up of 5+/-3 years, all-cause mortality, cardiac events, stroke and progression to kidney failure were noted.

RESULTS

Death was recorded in 83 patients (14%) of which 49% were due to cardiac causes. Non-fatal myocardial infarction occurred in 38 patients (6%), stroke in 46 (8%) and progression to kidney failure in 35 (6%). By multivariate analysis, patients with major declines in resting (>20%) and post-exercise (>30%) ABI were at increased risk of all-cause mortality (HR: 3.3, 95% CI: 1.5-7.2, HR: 3.0, 95% CI: 1.4-6.4, respectively), cardiac events (HR: 3.1, 95% CI: 1.3-7.2, HR: 2.4, 95% CI: 1.1-5.6, respectively), stroke (HR: 4.2, 95% CI: 1.6-10.4, HR: 3.9, 95% CI: 1.4-10.2, respectively) and kidney failure (HR: 2.7, 95% CI: 1.1-7.5, HR: 6.9, 95% CI: 1.5-31.5, respectively), compared to patients with no declines in ABI.

CONCLUSIONS

This study shows that major 1-year declines in resting and post-exercise ABI are associated with all-cause mortality, cardiac events, stroke and kidney failure in patients with PAD.

Vascular assessment and reconstruction of the ischemic diabetic limb

Peripheral artery disease (PAD) is a common finding among diabetic patients and is usually secondary to atherosclerosis. PAD in diabetic patients tends to be more malignant, presenting with diffuse involvement and more complications. Unless the ischemia is addressed concomitantly with local problems in the foot, resulting problems can lead to extensive tissue loss and major amputation. Lower extremity atherosclerotic complications in diabetic patients require considerable dedication and aggressiveness if limb loss is to be avoided.

Association of ambulatory use of statins and beta-blockers with long-term mortality after vascular surgery

BACKGROUND

The use of drugs to improve postoperative outcomes has focused on short-term end points and centered on beta-blockers. Emerging evidence suggests statins may also improve postoperative outcomes.

OBJECTIVE

We sought to ascertain if the ambulatory use of statins and/or beta-blockers was associated with a reduction in long-term mortality after vascular surgery.

DESIGN

Retrospective cohort study with a median follow-up of 2.7 years.

SETTING

Regional multicenter study at Veterans Affairs medical centers.

PATIENTS

Three thousand and sixty-two patients presenting for vascular surgery.

MEASUREMENTS

Patients were categorized as using statins or beta-blockers if they filled a prescription for the study drug within 30 days of surgery. Survival analyses, propensity score methods, and stratifications by the revised cardiac risk index (RCRI) were performed.

RESULTS

Propensity-adjusted ambulatory use of statins and beta-blockers was associated with a reduction in mortality over the study period compared with nonuse of these medications hazard ratio [HR] = 0.78 [95% CI: 0.67-0.92], P = .0021, and number needed to treat (NNT) = 22 for statins; HR = 0.84 [95% CI: 0.73-0.96], P = .0106, and NNT = 30 for beta-blockers. In addition, for propensity-adjusted use of both statins and beta-blockers compared with neither the HR was 0.56 [95% CI: 0.42-0.74] P < .0001, and NNT was 9. The RCRI confirmed combination statin and beta-blocker use was beneficial at all levels of risk. Use of the combination study drugs by the highest-risk patients was associated with a 33% decrease in mortality after 2 years (P = .0106).

CONCLUSIONS

The use of ambulatory statins alone or in combination with beta-blockers is associated with a reduction in long-term mortality after vascular surgery, and combination use benefits patients at all levels of risk.

Combined antiplatelet and anticoagulant therapy: clinical benefits and risks

The combination of anticoagulant and antiplatelet therapy is more effective than antiplatelet therapy alone for the initial and long-term management of acute coronary syndromes but increases the risk of bleeding. Antiplatelet therapy is often combined with oral anticoagulants in patients with an indication for warfarin therapy (e.g. atrial fibrillation) who also have an indication for antiplatelet therapy (e.g. coronary artery disease) but the appropriateness of such an approach is unresolved. Anticoagulation appears to be as effective as antiplatelet therapy for long-term management of acute coronary syndrome and stroke, and possibly peripheral artery disease, but causes more bleeding. Therefore, in such patients who develop atrial fibrillation, switching from antiplatelet therapy to anticoagulants might be all that is required. The combination of anticoagulant and antiplatelet therapy has only been proven to provide additional benefit over anticoagulants alone in patients with prosthetic heart valves. The combination of aspirin and clopidogrel is not as effective as oral anticoagulants in patients with atrial fibrillation, whereas the combination of aspirin and clopidogrel is more effective than oral anticoagulants in patients with coronary stents. Whether the benefits of triple therapy outweigh the risks in patients with atrial fibrillation and coronary stents requires evaluation in randomized trials.

Process of care and outcomes in patients with peripheral arterial disease

BACKGROUND

We investigated the association of process of care measures with adverse limb and systemic events in patients with peripheral arterial disease (PAD).

METHODS

We conducted a retrospective cohort study of patients with PAD, as defined by an ankle-brachial index (ABI) <0.9. The index date was defined as the date, during 1995 to 1998, when the patient was seen in the Michael E. DeBakey VA Medical Center noninvasive vascular laboratory and found to have PAD. We conducted a chart review for process of care variables starting 3 years before the index date and ending at the time of the first event or the final visit (December 31, 2001), whichever occurred first. We examined the association between PAD process of care measures, including risk factor control, and prescribing of medication, with time of the patient's first major limb event or death.

RESULTS

Of the 796 patients (mean age, 65 +/- 9.9 years), 230 (28.9% experienced an adverse limb event (136 lower-extremity bypass, 94 lower-extremity amputation), and 354 (44.5%) died. Of the patients who died, 247 died without a preceding limb event. Glucose control was protective against death or a limb event with a hazard ratio (HR) of 0.74 (95% confidence limits [CL] 0.60, 0.91, P = 0.004). African Americans were at 2.8 (95% CL 1.7, 4.5) times the risk of Whites or Hispanics for an adverse limb event. However, this risk was no longer significant if their glucose was controlled. For process measures, the dispensing of PAD specific medication (HR 1.4, 95% CL 1.1, 1.7) was associated an increased risk for an adverse outcome.

CONCLUSIONS

Our data suggest that glucose control is key to reducing the risk for adverse outcomes, particularly limb events in African Americans. Certain process of care measures, as markers of disease severity and disease management, are associated with poor outcomes in patients with PAD. Further work is needed to determine the role of early disease intervention to reduce poor outcomes in patients with PAD.

The medial versus the posterior approach in the repair of popliteal artery aneurysms: A multicenter case-matched study

OBJECTIVES

This study was conducted to compare the early and mid-term results of the medial and posterior approaches in the surgical treatment of popliteal artery aneurysms (PAAs).

METHODS

From 1992 to 2006 in three hospitals, 110 popliteal aneurysms needed surgical repair by a posterior or a medial approach. Of 36 aneurysms repaired by the posterior approach, 33 could be case-matched to a medially excluded PAA according to the criteria of (1) patient age, (2) cardiovascular comorbidity, (3) indication for PAA repair, (4) diameter of PAA at time of surgical repair, (5) number of distal outflow vessels at time of surgical repair, and (6) type of bypass or interposition graft (venous or polytetrafluoroethylene).

RESULTS

During the 30-day postoperative period, seven complications (21%) occurred in each group, no patients died, and no amputations were necessary. Two patients in the posterior group vs none in the medial group (P < .05) needed thrombectomy because of occlusion of the reconstruction. The mean follow-up was 47 months (range, 2 to 176). In this period, 13 deaths occurred, but none were related to the previous interventions. The primary patency rates at 6 months and at 1, 3, and 4 years were 84%, 79%, 66%, and 66% in the posterior group and 96% (P < .05), 93% (P < .05), 76% (P = NS), and 69 % (P = NS) for the medial group, respectively. The secondary patency rates at 6 months, and at 1, 3, and 4 years were 100%, 100%, 100%, and 90% in the posterior group and 96%, 96%, 96%, and 90% in the medial group, respectively (P = NS). Limb salvage rates were 97% for the posterior group and 100% for the medial group (P = NS). No neurologic complications or venous damage was seen in either group. Irrespective of approach, venous reconstructions resulted in significantly higher patency rates compared with prosthetic reconstructions at the 3-year follow-up (84% vs 67%, P < .01). During follow-up, which included duplex scanning, two patients in the medial group needed renewed surgical intervention and posterior exclusion because of persistent flow and growth of the native aneurysm.

CONCLUSION

Early (<1 year) primary patency rates of the medial approach were significantly better than the posterior approach, possibly because of the limited posterior exposure. However, in the absence of a significant difference in long-term primary and secondary patency rates between the posterior and medial approach, and considering the substantial risk of aneurysm growth after medial approach (up to 22%), the posterior approach might be the surgical method of preference for PAA repair in the long run.

Contemporary use of clopidogrel in patients with coronary artery disease

Antiplatelet agents have long served as the cornerstone of pharmacologic therapy to prevent atherothrombotic events. The thienopyridines have risen to prominence as both an alternative and adjunctive treatment to aspirin monotherapy. These agents prevent platelet aggregation by selectively and irreversibly blocking the platelet ADP P2Y12 receptor. In this article we focus on the use of clopidogrel in the contemporary management of coronary artery disease. We assess the use of clopidogrel following revascularization for coronary artery disease with percutaneous coronary intervention, particularly after deployment of drug-eluting stents. Finally, we address some aspects of clopidogrel resistance.

[Abdominal aortic aneurysm and renovascular disease]

Recent technological advances in the diagnosis and therapy of abdominal aortic aneurysm and renovascular disease are continuing to bring about changes in the way patients suffering from these conditions are treated. The prevalence of both these conditions is increasing. This is due to greater life-expectancy in patients with arteriosclerosis, a pathogenetic factor underlying both conditions. The application of diagnostic imaging techniques to non-vascular conditions has led to the early diagnosis of abdominal aortic aneurysm. Clinical suspicion of reno-vascular disease can be confirmed easily using high-resolution diagnostic imaging modalities such as CT angiography and magnetic resonance angiography. Endovascular intervention is successfully replacing conventional surgical repair techniques, with the result that it may be possible to improve outcome in both conditions using effective and minimally invasive approaches. Future technological developments will enable these endovascular techniques to be applied in the large majority of patients with abdominal aortic aneurysm or renovascular disease.

Fibromuscular dysplasia

Fibromuscular dysplasia (FMD), formerly called fibromuscular fibroplasia, is a group of nonatherosclerotic, noninflammatory arterial diseases that most commonly involve the renal and carotid arteries. The prevalence of symptomatic renal artery FMD is about 4/1000 and the prevalence of cervicocranial FMD is probably half that. Histological classification discriminates three main subtypes, intimal, medial and perimedial, which may be associated in a single patient. Angiographic classification includes the multifocal type, with multiple stenoses and the 'string-of-beads' appearance that is related to medial FMD, and tubular and focal types, which are not clearly related to specific histological lesions. Renovascular hypertension is the most common manifestation of renal artery FMD. Multifocal stenoses with the 'string-of-beads' appearance are observed at angiography in more than 80% of cases, mostly in women aged between 30 and 50 years; they generally involve the middle and distal two-thirds of the main renal artery and in some case also renal artery branches. Cervicocranial FMD can be complicated by dissection with headache, Horner's syndrome or stroke, or can be associated with intracerebral aneurysms with a risk of subarachnoid or intracerebral hemorrhage. The etiology of FMD is unknown, although various hormonal and mechanical factors have been suggested. Subclinical lesions are found at arterial sites distant from the stenotic arteries, and this suggests that FMD is a systemic arterial disease. It appears to be familial in 10% of cases. Noninvasive diagnostic tests include, in increasing order of accuracy, ultrasonography, magnetic resonance angiography and computed tomography angiography. The gold standard for diagnosing FMD is catheter angiography, but this invasive procedure is only used for patients in whom it is clinically pertinent to proceed with revascularization during the same procedure. Differential diagnosis include atherosclerotic stenoses and stenoses associated with vascular Ehlers-Danlos and Williams' syndromes, and type 1 neurofibromatosis. Management of cases with renovascular hypertension includes antihypertensive therapy, percutaneous angioplasty of severe stenoses, and reconstructive surgery in cases with complex FMD that extends to segmental arteries. The therapeutic options for securing ruptured intracerebral aneurysms are microvascular neurosurgical clipping and endovascular coiling. Stenosis progression in renal artery FMD is slow and rarely leads to ischemic renal failure.

Peripheral Arterial Disease: A Guide for Nephrologists

Cardiovascular disease is a major source of morbidity and mortality for patients with chronic kidney disease (CKD). Peripheral arterial disease (PAD) is a strong predictor of coronary artery disease and a risk factor for mortality in the general population. This is of particular interest to nephrologists because the risk for PAD is increased in CKD. Often, PAD is overlooked as a source of morbidity and as a cardiovascular risk factor in this population. This review serves as an overview of the epidemiology, screening, diagnosis, and treatment of PAD with an emphasis on CKD.

Improving risk assessment with cardiac testing in peripheral arterial disease

PURPOSE

The study's objective was to evaluate the prognostic value of left ventricular ejection fraction and stress-induced ischemia during dobutamine stress echocardiography, in addition to ankle-brachial index measurements and clinical risk factors in patients with suspected or known peripheral arterial disease.

METHODS

In 852 patients with suspected or known peripheral arterial disease (mean age 63 years, 70% male), the ankle-brachial index was measured, left ventricular ejection fraction was assessed, and all patients underwent additional stress testing. Endpoints were all-cause mortality and hard cardiac events (cardiac death or nonfatal myocardial infarction).

RESULTS

During a mean follow-up of 7.6+/-4.4 years, death occurred in 288 patients (34%), and hard cardiac events occurred in 216 patients (25%). Mean left ventricular ejection fraction was 50%+/-17%, and stress-induced ischemia was observed in 352 patients (41%). In multivariate analysis with adjustment for clinical risk factors and ankle-brachial index, each 5% decrease in left ventricular ejection fraction was associated with increased all-cause mortality (hazard ratio [HR] 1.05, 95% confidence interval [CI], 1.02-1.09) and hard events (HR 1.14, 95% CI, 1.08-1.21). Stress-induced ischemia also independently predicted all-cause mortality (HR 2.01, 95% CI, 1.38-2.79) and hard events (HR 2.06, 95% CI, 1.39-3.08). Left ventricular ejection fraction and stress-induced ischemia provided incremental prognostic information over clinical data and ankle-brachial index values (P <.001).

CONCLUSIONS

Left ventricular ejection fraction and stress-induced ischemia independently predict long-term outcome and improve prognostic risk assessment, in addition to ankle-brachial index and clinical risk factors in patients with suspected or known peripheral arterial disease.

Association of novel risk factors with the ankle brachial index in African American and non-Hispanic white populations

OBJECTIVES

To investigate whether novel risk factors, including C-reactive protein (CRP), fibrinogen, lipoprotein(a) [Lp(a)], and homocysteine levels, are associated with the ankle brachial index (ABI) in African American and non-Hispanic white populations and whether novel risk factors account for ethnic differences in peripheral arterial disease (PAD).

PARTICIPANTS AND METHODS

Between December 2000 and October 2004, original participants in the Genetic Epidemiology Network of Arteriopathy study returned for a second study visit to undergo measurement of risk factors and ABI. The CRP, Lp(a), and homocysteine levels were log transformed to reduce skewness. Multivariable regression analyses were used to assess whether a novel risk factor was associated with ABI after adjustment for conventional risk factors and whether ethnicity was associated with PAD (ABI, <or=0.95) after adjustment for conventional and novel risk factors.

RESULTS

Of 2229 study participants, the ABI was determined in 1395 African American participants (mean +/- SD age, 63 +/- 9 years; 71% women) and 834 white participants (mean +/- SD age, 58 +/- 9 years; 62% women) who belonged to hypertensive sibships. The mean ABI was lower in African American than in white individuals (0.99 +/- 0.1 vs 1.13 +/- 0.1; P < .001). In both ethnic groups, higher levels of CRP, fibrinogen, and homocysteine were each associated with a lower ABI after adjustment for conventional risk factors. In African American participants, the Lp(a) level was also significantly associated with the ABI. African American ethnicity was associated with the presence of PAD after adjustment for conventional risk factors (men: odds ratio [OR], 3.04; 95% confidence interval [CI], 1.80-5.15; women: OR, 2.82; 95% CI, 1.85-4.29), but the risk was significantly attenuated after additional adjustment for novel risk factors (men: OR, 2.11; 95% CI, 1.21-3.70; women: OR, 1.98; 95% CI, 1.26-3.11).

CONCLUSION

Novel risk factors are associated with interindividual variation in ABI in African American and non-Hispanic white populations and partly account for the increased risk of PAD associated with African American ethnicity.

Turning back the clock: regression of abdominal aortic aneurysms via pharmacotherapy

Abdominal aortic aneurysm (AAA) is a common disease that causes progressive expansion and rupture of the aorta with high mortality. There is a large and unmet need for nonsurgical treatment for AAA. Research has shown that an intricate network of inflammatory cells and interstitial cells contributes to the formation of AAA by producing pro-inflammatory mediators that activate enzymes to degrade the extracellular matrix (ECM) and impair ECM biosynthesis. Pharmacological agents such as statins and angiotensin-converting enzyme inhibitors may promote tissue stabilization in AAA by diminishing pro-inflammatory signaling and normalizing metabolism of the ECM. Our recent experiments in animal models demonstrate that inhibition of c-Jun N terminal kinase (JNK) inhibits multiple pathological processes and causes regression of established AAA. Thus, emerging evidence indicates that pharmacological intervention targeting pro-inflammatory signaling and abnormal ECM metabolism is a promising strategy for treatment of AAA.

Critical limb ischemia

Critical limb ischemia (CLI) is the most severe manifestation of peripheral artery disease (PAD). Without timely recognition, appropriate diagnosis, and revascularization, patients with CLI are at risk for amputation or potentially fatal complications. The past decade has seen substantial growth in endovascular CLI therapies and options now exist for treating long-segment lower-extremity arterial occlusive disease, but surgical bypass may yield more durable results. Patients who are younger, more active, and at low risk for surgery may have better outcomes with an operation. Surgical treatment is also indicated for failures of endovascular therapy, which may include early technical failures or later occlusion after placement of stents or other interventions.

[Non-surgical treatment of critical limb ischemia]

In critical limb ischemia, the aim of the treatment is to increase the arterial blood flow in the affected limb in order to relieve pain, heal trophic lesions, and avoid amputation. In patients in whom revascularization is not possible, medical treatment can occasionally be considered although it may not prevent limb loss in many patients. Medical strategies include the use of antalgics frequently opioids, antiplatet agents and prevention of venous thromboembolism. Selected patients may benefit from intravenous prostanoids, although their efficacy is unconstant. Maintenance of the bed in a dependant position may increase blood perfusion in the affected limbs. Gene and cell therapies, although promissing strategies, are currently evaluated in large clinical trials.