Peripheral arterial disease detection, awareness, and treatment in primary care

Classic intermittent claudication is an uncommon manifestation of lower extremity peripheral arterial disease in hospitalized patients with coronary artery disease

Synchronous peripheral arterial disease (PAD) and coronary artery disease (CAD) is common. Standardized questionnaires such as the Rose/WHO questionnaire and later the Edinburgh modification of this questionnaire were developed to screen for PAD. Little data are available on the sensitivity of these questionnaires in hospitalized patients with CAD. The aim of this study was to determine the accuracy of these questionnaires and the prevalence of classic intermittent claudication in hospitalized patients with CAD. Medically stable patients with CAD were invited to participate before hospital discharge. The patients answered both the Rose/WHO and Edinburgh modification claudication questionnaires and had an ankle-brachial index (ABI) measured. An ABI less than or equal to 0.9 was considered to be indicative of significant PAD. Patients who had undergone previous lower extremity revascularization for PAD and had a corrected ABI greater than 0.9 were excluded. Ninety-five patients (66 men) were recruited. By measuring the ABI, 35 patients (25 men) were found to have significant PAD. An additional 3 patients who had an ABI corrected by lower extremity revascularization were excluded from the analysis. The Rose/WHO questionnaire had a sensitivity, specificity, and overall accuracy (95% CI) of 14.3% (2.7-25.9%), 96.7% (92.1-100%), and 66.3% (56.8-75.8%), respectively. The Edinburgh modification of the Rose/WHO questionnaire had a sensitivity, specificity, and overall accuracy (95% CI) of 28.6% (13.6-43.5%), 90.0% (82.4-97.6%), 67.4% (57.9-76.8%), respectively. Despite the high incidence of synchronous PAD in hospitalized patients with CAD, traditional claudication questionnaires are insensitive to PAD detection. Classic claudication is an uncommon manifestation of PAD in hospitalized patients with CAD.

Peripheral arterial disease: clinical assessment and indications for revascularization in the patient with diabetes

Peripheral arterial disease (PAD) is an under-recognized complication of diabetes. Recently, prevalence estimates in patients with diabetes over 50 years of age have been placed at 25% to 30%. The main reason for under-reporting is the largely asymptomatic nature of PAD in diabetes. Nonetheless, it is important to diagnose PAD because it is a marker of systemic atherosclerosis with excess cardiovascular risk, and it may identify a patient who may develop progressive disability and risk of limb loss. The most sensitive and specific diagnostic tool is an ankle-brachial index. Imaging studies are performed in patients who are candidates for revascularization. The most durable and effective revascularization procedure for PAD in diabetes is surgical bypass with saphenous vein as the conduit. Endovascular interventions are best used in patients with proximal disease with short-segment stenoses. The indications for revascularization have been immutable for decades, namely rest pain, ischemic ulceration, or gangrene. Presently, clinicians would include "selected" patients with intermittent claudication who have disabling symptoms and proximal disease above the inguinal ligament.

Excess 1-year cardiovascular risk in elderly primary care patients with a low ankle–brachial index (ABI) and high homocysteine level

Previous studies in selected patient samples suggested a high risk for total mortality and cardiovascular (CV) morbidity associated not only with symptomatic, but also with asymptomatic peripheral arterial disease (PAD). Our aim was to assess the 1-year risk of death and CV morbidity associated with PAD in primary care. Furthermore, we quantified the strength of association between low ankle-brachial index (ABI, as indicator for PAD), plasma homocysteine (HC) levels, and various accepted PAD risk factors, and death and outcomes. In a prospective cohort study, 6880 unselected patients > or =65 years were followed up by 344 primary care physicians in Germany. At 1 year, all-cause mortality was 2.8% in patients with PAD and 0.9% in patients without PAD (odds ratio [OR] adjusted for age and gender: 2.7 [95% confidence interval: 1.7; 4.2]; multivariate adjusted OR: 2.0 [1.3; 3.3]). Mortality due to CV events was 1.6 versus 0.4% (OR: 3.7 [2.0; 6.9], adjusted OR: 2.5 [1.3; 4.9]). Patients with PAD and high HC values (> or =fourth quintile) had a markedly increased risk of premature death: OR versus no PAD/low HC level (<first quintile): 9.8 [3.2, 29.9], adjusted OR 6.6 [2.1, 20.9]. Patients with a low ABI have a substantially increased risk of (short-term) all-cause mortality. The combination of a low ABI and high HC level is particularly useful for identifying patients at excess risk.

Abnormal Ankle Brachial Indices may Predict Cardiovascular Disease Among Diabetic Patients Without Known Heart Disease

BACKGROUND

Cardiovascular disease remains the primary cause of diabetes-associated morbidity and mortality. Previous studies have failed to provide accurate, inexpensive, screening techniques to detect cardiovascular disease in diabetics. Ankle brachial indices (ABI) testing may be an effective screening technique for diabetics.

METHODS AND RESULTS

The aim of this 100-subject clinical study was to determine cardiovascular disease prevalence, via perfusion stress testing, in diabetic patients having abnormal ABI (<0.90) and without known heart disease who were referred to the South Carolina Heart Center, Columbia, SC for nuclear perfusion stress testing. Study data were analyzed using frequency and descriptive statistics and 2-sample T-testing. Mean subject age was 62+/-11 years, ABI 0.76+/-13, and ejection fraction 60+/-12%. Perfusion stress testing detected 49 abnormal electrocardiograms, 36 subjects with coronary ischemia, 20 with diminished left ventricular function, and 26 subjects having significant thinning of the myocardium. There were 71 subjects who tested positive for at least one form of cardiovascular disease. The sole predictive variable reaching significance for the presence of cardiovascular disease was an ABI score <0.90 (p< or =0.0001).

CONCLUSION

Cardiovascular disease may be predicted among diabetic patients via ABI scores and confirmed by nuclear perfusion testing.

Costs and medical care consequences associated with the diagnosis of peripheral arterial disease

BACKGROUND

Peripheral arterial disease (PAD) is increasingly recognised as an indicator of disseminated atherothrombosis, but its impact on use of healthcare resources is not well understood.

OBJECTIVE

To provide a quantitative description of the resource utilisation and costs incurred following PAD.

METHODS

Hospitalisations, physician visits and the corresponding direct medical costs were examined in 16,440 patients with a diagnosis of PAD (1985--1995) in Saskatchewan, Canada, and compared with 15,590 reference patients with a diagnosis of myocardial infarction (MI) [1990--1995]. Medical history and patient characteristics were available retrospectively to January 1980 and follow-up to December 2000. Rates and timing of all-cause and cardiovascular hospitalisations and physician visits within discrete periods in the 10 years following PAD diagnosis, and 5 years following MI, were evaluated, as were lengths of stay and predictors of hospitalisation.

RESULTS

Average follow-up was 5.9 years among patients with PAD and 3.6 years for MI. Half (55%) of patients with PAD were male versus 64% of reference patients. The mean ages were 67.3 and 66.9 years, respectively. Patients with PAD were hospitalised most frequently soon after diagnosis, with rates subsequently decreasing to 0.14 per month. These rates were similar in the reference group except for the period immediately following MI. The average 5-year cost post-diagnosis (2002 Can dollars) per patient was 41,968 Can dollars vs 48,578 Can dollars for the reference population.

CONCLUSIONS

A diagnosis of PAD not only imposes a severe burden on patients and their families, but it also significantly increases the use of healthcare resources and the associated costs. By the end of year 1, this burden is comparable with a diagnosis of MI.

Early experience in the application of distal protection devices in treatment of peripheral vascular disease of the lower extremities

The objectives of this study were to reduce the risk of showering distal vessels with thromboemboli created during percutaneous interventions of the arteries in the lower extremities. Distal protection devices have been used in coronary and carotid interventions. Hence, using similar techniques, these filters and occlusion balloons were advanced past the targeted lesions and distally into femoral and popliteal arteries. Once opened, these devices allowed standard angioplasty and stent placement and captured the dislodged thromboemboli. Five cases were performed with the distal protection devices. One case used the distal occlusion balloon and four with the filter system. All five passed the lesion and were deployed. All five devices were retrieved without incident and were retrieved with substantial debris. There were no adverse events. The use of distal protection to treat high-risk or unstable lesions in the lower extremities shows great promise. Further case will be needed to evaluate the device for feasibility and safety.

Ethnicity and peripheral arterial disease

OBJECTIVE

To determine whether race/ethnicity is an independent risk factor for peripheral arterial disease (PAD).

PATIENTS AND METHODS

From September 2000 through August 2001, we screened patients (age > or = 55 years) for PAD within 4 primary care clinics located in the Houston, Tex, area. Variables that were bivariately associated with PAD (P< or = .05) were selected for entry into a multivariate logistic regression model to determine the independent risk factors for PAD.

RESULTS

Among 403 patients (136 white, 136 African American, and 131 Latino patients, 81 of whom were Spanish speaking), the prevalence of PAD was 22.8% among African American patients, 13.7% among Latino patients, and 13.2% among white patients (P = .06). Within the multivariate model, adjusting for age, smoking status (odds ratio [OR], 2.58; 95% confidence interval [CI], 1.27-5.25), diabetes mellitus (OR, 2.98; 95% CI, 1.58-5.63), hypertension (OR, 2.58; 95% CI, 1.12-5.95), and education, African American and Latino patients were not more likely than white patients to have a diagnosis of PAD (OR 1.89, 95% CI 0.89-3.99 and OR 1.54, 95% CI 0.59-4.06, respectively).

CONCLUSION

After adjusting for atherosclerotic risk factors and level of education, ethnicity was not an independent risk factor for PAD. When determining ethnic variation in outcomes among patients with PAD, efforts are needed to better understand the role of the primary care setting to reduce the burden of social inequality on health.

Impact of Renal Insufficiency on Mortality in Advanced Lower Extremity Peripheral Arterial Disease

Renal insufficiency predicts mortality among patients who are treated for myocardial infarction and congestive heart failure, but its clinical significance in advanced peripheral arterial disease has not been evaluated. A national cohort of 5787 male veterans who received an initial diagnosis of rest pain, ischemic ulceration, or gangrene between January 1, 2000, and September 30, 2002, and had at least one serum creatinine measurement within 3 mo before diagnosis were identified. Sixty-two percent (n = 3561) of cohort members had normal or mildly reduced renal function (GFR > or =60 ml/min per 1.73 m(2)), 30% (n = 1742) had moderate renal insufficiency (GFR 30 to 59 ml/min per 1.73 m(2)), and 8% (n = 484) had severe renal insufficiency or renal failure (GFR <30 ml/min per 1.73 m(2)) but were not on dialysis. The percentages of patients who presented with gangrene or ischemic ulceration rather than rest pain increased with declining renal function (70, 77, and 87%; P < 0.001), as did 1-yr mortality risk (17, 27, and 44%; P < 0.001). After adjustment for demographic and clinical characteristics, patients with a GFR of 30 to 59 ml/min per 1.73 m(2) (odds ratio, 1.32; 95% confidence interval, 1.13 to 1.53) and <30 ml/min per 1.73 m(2) (odds ratio, 2.97; 95% confidence interval, 2.39 to 3.69) had a significantly increased odds of death within 1 yr of cohort entry. Both moderate and severe renal insufficiency are associated with an increased odds of death in patients with critical limb ischemia. Death rates were particularly high among those with a GFR <30 ml/min per 1.73 m(2). This finding may be partly explained by their more frequent presentation with ischemic ulceration or gangrene rather than rest pain.

Effect of glucocorticoids on the arteries in rheumatoid arthritis

OBJECTIVE

Glucocorticoids are suspected to cause atherosclerosis. Because of the possibility that their antiinflammatory effect may be antiatherogenic, this study investigated the effect of glucocorticoids on the arteries of patients with rheumatoid arthritis (RA).

METHODS

We assessed the arteries of 647 patients with RA. Central atherosclerosis was measured using high-resolution carotid ultrasound for the presence of plaque and for the extent of carotid artery intima-media thickness (CaIMT). Peripheral atherosclerosis was assessed using the systolic pressures of the dorsal pedal, posterior tibial, and brachial arteries to obtain the ankle-brachial index (ABI). Cumulative glucocorticoid dose was determined using pharmacy records, supplemented by self-report. Cardiovascular (CV) risk factors and RA clinical manifestations were ascertained using clinical and laboratory methods.

RESULTS

Among the RA patients studied, 427 (66%) had received glucocorticoids. Of those who had never received glucocorticoids, 100 (47%) of 215 had carotid plaque and 17 (8%) of 219 had > or =1 incompressible lower-limb artery (ABI >1.3). Among patients in the highest tertile of lifetime glucocorticoid exposure (>16.24 gm prednisone), the frequency of carotid plaque increased to 85 (62%) of 138 (P = 0.006) and that of lower-limb arterial incompressibility increased to 24 (17%) of 140 (P = 0.008), with differences remaining significant after adjustment for age at onset, disease duration, sex, CV risk factors, and RA clinical manifestations (tender, swollen, and deformed joint counts, subcutaneous nodules, rheumatoid factor seropositivity, and erythrocyte sedimentation rate). The CaIMT also displayed an increase with higher glucocorticoid exposure, but the differences did not reach significance. Lower-limb artery obstruction (ABI < or =0.9) was not associated with glucocorticoid exposure.

CONCLUSION

In this RA sample, glucocorticoid exposure was associated with carotid plaque and arterial incompressibility, independent of CV risk factors and RA clinical manifestations. This supports a role for glucocorticoids in the CV complications that occur in RA.

L’artériopathie des membres inférieurs en médecine générale. Quelle prise en charge ?

OBJECTIVE

The purpose of this study was to analyze the results of the ATTEST study in order to evaluate general medicine management practices for peripheral arterial disease (PAD). Our analysis was based on the guidelines for good practice which recommend measurement of the systolic pressure index (SPI), search for other localizations of atherothrombosis, treatment of risk factors including smoking, walking exercises, and long-term prescription of anti-platelets.

METHODS

ATTEST is a cross-sectional multicentric observational epidemiologic study conducted in metropolitan France. The study has recruited 8.475 analyzable patients with symptomatic PAD alone (3811 patients) or associated with other atherothrombotic localizations (2416 patients) or other cardiovascular diseases (2248 patients). These patients were followed by 3020 physicians. The current analysis thus included 6227 patients (81.2% men, 18.8% women, mean age 67.2 years), including 78.8% who had reached the stage of intermittent claudication. Risk factors included current or past smoking (61%), hypercholesterolemia (66.3%), hypertension (63.1%) and diabetes mellitus (26%).

RESULTS

Arterial duplex Doppler exams of the lower limbs were performed in 91.2% of the patients but measurement of the SPI for diagnostic purposes had been performed in only 17%. The majority (85.8%) of the patients with proven coronary artery disease or cervico-encephalic involvement had had an ECG and 69.3% had had a duplex Doppler of the supra-aortic trunks. Smoking continued in 39% of the patients and an aid to cease smoking had been prescribed for only 7% of the patients who were non-smokers for less than one year. Nearly two-thirds of the patients analyzed had received advice concerning physical activities. Finally, anti-platelets had been prescribed for 92.2% of the patients.

CONCLUSIONS

The general practitioner plays a crucial role in the diagnosis and treatment of PAD. Although measurement of the SPI is recommended as an early diagnostic tool and for evaluation of severity, it had been performed in less than one-third of the patients. Search for another localization of atherothrombosis had been performed in more than half of the patients. The physicians generally delivered advice on physical exercise and prescribed anti-platelets. The fight against smoking was however largely insufficient. The results of this study warrant further optimization of the collaboration between general practitioners and vascular disease specialists.

Peripheral arterial disease, diabetes, and mortality

OBJECTIVE

The aims of this study were to provide estimates of 1) the risk of mortality for individuals with both diabetes and peripheral arterial disease (PAD) relative to that for individuals with either condition alone and 2) the association between PAD progression and mortality for individuals with diabetes, PAD, and both conditions.

RESEARCH DESIGN AND METHODS

This longitudinal cohort study was conducted in Rochester, Minnesota. Local residents age 50-70 years with a prior diagnosis of PAD and/or diabetes were identified from the Mayo Clinic diagnostic registry and invited to a baseline examination (1977-1978). Those who met inclusion criteria were assessed for PAD progression at 2 and 4 years and followed for vital status through 31 December 1999.

RESULTS

The numbers who met criteria for PAD, diabetes, and both conditions at baseline were 149, 238, and 186, respectively. Within each group, observed survival was less than expected (P <0.001). The adjusted risk of death for both conditions was 2.2 times that for PAD alone. Among the 449 who returned at 4 years, the risk of subsequent death was greater for those whose PAD had progressed; among individuals with diabetes alone at baseline, 100% (17 of 17) who met criteria for PAD progression were dead by 31 December 1999 compared with 62% (111 of 178) of those who had not met criteria (adjusted relative hazard 2.29 [95% CI 1.30-4.02], P=0.004). The increased mortality associated with PAD progression was significant only for individuals with diabetes (alone or with PAD).

CONCLUSIONS

Diabetes is a risk factor for both PAD and PAD-associated mortality, emphasizing the critical need to detect and monitor PAD in diabetic patients.

A pilot exercise intervention to improve lower extremity functioning in peripheral arterial disease unaccompanied by intermittent claudication

PURPOSE

A pilot study was conducted to test the feasibility of supervised treadmill exercise training to improve functioning in study participants with peripheral arterial disease who did not have classical symptoms of intermittent claudication.

METHODS

For this study, 32 men and women with peripheral arterial disease but no symptoms of claudication were randomized to exercise training or usual care. The intervention was a 12-week supervised treadmill walking program. Outcomes included 6-minute walk distance, maximum treadmill walking distance, and 4-meter walking velocity. Participant-reported community walking ability was measured with the Walking Impairment Questionnaire (WIQ). Inflammatory blood factor levels also were measured.

RESULTS

Altogether, 25 participants who completed follow-up testing were included in intention-to-treat analyses. Of 24 participants (58%) randomized to exercise, 14 completed the entire exercise training program. The participants randomized to the intervention showed greater improvement in their WIQ walking speed score than the control subjects (P =.05). The participants randomized to the intervention showed improvements in their 6-minute walk distance (1134 +/- 347 vs 1266 +/- 295 feet; P =.03), maximal treadmill walking distance (389 +/- 248 vs 585 +/- 293 feet; P <.001), WIQ distance score (52.3 +/- 29.1 vs 63.1 +/- 25.1; P =.002), and WIQ speed score (48.7 +/- 26.8 vs 59.7 +/- 22.7; P =.008). The participants randomized to the control condition showed improvements in maximal treadmill walking distance (362 +/- 180 vs 513 +/- 237 feet; P =.014). There were no significant changes in the inflammatory blood factors after exercise.

CONCLUSIONS

This pilot study demonstrated that a supervised treadmill walking program may be feasible and may improve functioning for individuals with peripheral arterial disease who do not have classical symptoms of intermittent claudication. Further study is needed with a larger sample to identify optimal exercise methods that improve lower extremity functioning in men and women with peripheral arterial disease who do not have intermittent claudication.

Medical Treatment of Peripheral Arterial Disease: A Comprehensive Review

Peripheral arterial disease (PAD) is a common manifestation of atherosclerosis that affects more than 10 million people in the United States. The risk factors associated with PAD are similar to those found in patients with coronary artery disease and cerebrovascular disease. Medical therapy of PAD must include modification of cardiovascular risk factors with application of strict secondary prevention guidelines. For improvement in quality of life, a structured exercise rehabilitation program remains the most effective noninterventional treatment strategy, but it is difficult to employ from economic and patient-compliance perspectives. Newer pharmacologic therapies have demonstrated efficacy in patients with intermittent claudication. Emerging strategies for management of these patients include revascularization and maximal medical therapy for improvement of physical function as well as reduction in risk for subsequent major cardiovascular events. This article will review the clinical data supporting aggressive medical interventions for patients with PAD.

Magnetic resonance imaging of the peripheral vasculature

BACKGROUND

Atherosclerotic disease of the peripheral vasculature is a prevalent condition for which catheter-based techniques have been considered to be the gold standard for diagnosis. However, because of their invasive nature, these techniques inherently have the potential for complications. Non-invasive diagnostic techniques have historically been limited by low accuracy and high operator dependence. Magnetic resonance angiography (MRA) is a new approach that has diagnostic accuracy comparable with invasive angiography.

METHODS

The literature on MRA for evaluation of carotid, mesenteric, renal, and lower-extremity arterial disease was extensively reviewed. Helpful diagnostic algorithms on the basis of the literature are also provided.

RESULTS

MRA is both sensitive and specific when compared with invasive angiography for the evaluation of peripheral arterial disease and avoids the potential for complications resulting from arterial puncture and use of iodinated contrast.

CONCLUSION

Current MRA techniques are diagnostically robust and have proven to be a highly accurate, safe, and convenient means of diagnosing atherosclerotic disease of the peripheral vascular system.

Predictive Power of Cardiovascular Risk Factors for Detecting Peripheral Vascular Disease

OBJECTIVES

Peripheral vascular disease (PVD) is underdiagnosed in primary care due to the absence of established criteria to warrant diagnostic testing. Our goal was to establish a risk factor hierarchy to enable earlier diagnosis of PVD.

METHODS

Data sets of 142 patients with abnormal ankle brachial indices (ABI) were randomly selected from our patient database to determine the prevalence of specific cardiovascular risk factors and demographic data. An ABI score < 0.90 is diagnostic of PVD. Patients were stratified into mild (0.75-0.89), moderate (0.50-0.74), and severe disease (< 0.50).

RESULTS

Mean age was 69 +/- 9.9, ABI 0.65 +/- 0.16. Risk factor prevalence: diabetes, 42%; hypertension, 87%; tobacco use, 34%; hyperlipidemia, 53%; obesity, 24%; cardiovascular disease (CVD), 69%; stroke, 15%. Total risk factors per patient v = 3.2 +/- 1.3. Disease severity stratifications: mild, n = 46 (age v = 68.6 +/- 10.4, ABI v = 0.82 +/- 0.05); moderate, n = 72 (age v = 69.9 +/- 9.4, ABI v = 0.62 +/- 0.07); severe, n = 24 (age v = 67.5 +/- 10.9, ABI v = 0.40 +/- 0.06). Independent variable mean differences: hypertension-CVD (P = 0.0002); CVD-hyperlipidemia (P = 0.002); hyperlipidemia-diabetes (P = 0.0008); diabetes-tobacco use (P = 0.001); tobacco use-obesity (P = 0.0003); obesity-stroke (P = 0.05). Independent variable mean differences were significant across disease severity (P < 0.00001).

CONCLUSIONS

Our study establishes the following hierarchy of cardiovascular risk factors as predictors of PVD: hypertension, cardiovascular disease, hyperlipidemia, diabetes, tobacco use, obesity, stroke.

Peripheral arterial disease: prognostic significance and prevention of atherothrombotic complications

The prevalence of peripheral arterial disease (PAD) in people aged over 55 years is 10%-25% and increases with age; 70%-80% of affected individuals are asymptomatic; only a minority ever require revascularisation or amputation. Patients with PAD alone have the same relative risk of death from cardiovascular causes as those with coronary or cerebrovascular disease, and are four times more likely to die within 10 years than patients without the disease. The ankle-brachial pressure index (ABPI) is a simple, non-invasive bedside tool for diagnosing PAD - an ABPI less than 0.9 is considered diagnostic of PAD. About half of patients with PAD (defined by an abnormal ABPI) have symptomatic coronary or cerebral vascular disease. The ABPI is an independent predictor of coronary and cerebrovascular morbidity and mortality. Patients with PAD require medical management to prevent future coronary and cerebral vascular events. There are currently insufficient data to recommend routine population screening for asymptomatic PAD using the ABPI.

Evidence-based treatment of lipids in the elderly

The elderly (men aged 65 years and older and women aged 75 years and older) constitute a population at high absolute risk for the morbidity and mortality of atherosclerotic cardiovascular disease. Statins have been shown in multiple large trials to reduce the burden of atherosclerotic disease in both middle-aged and elderly patients at elevated risk for coronary events, stroke, and death. We reviewed the major statin trials with particular emphasis on the significant number of elderly subjects. The impact of statins on the elderly, both positive and negative, is tabulated. In addition, we briefly discuss risk assessment in the elderly because selection of elderly patients for intensive low-density lipoprotein cholesterol reduction with statins requires clinical judgment that must weigh the need for subclinical measures of atherosclerosis. We also consider negative aspects, risks, and costs of such therapy.

L’index de pression systolique, un puissant marqueur de risque d’AOMI

A MARKER OF PERIPHERAL ARTERIAL DISEASE: The measurement of the ankle/arm index (AAI) is a simple, rapid and inexpensive means for the assessment of distal lower limb perfusion. Its decrease reveals an alteration in the patient's arterial status. Consecutively, AAI is an excellent marker of peripheral arterial disease, well before the onset of functional consequences. A TRIPLE MARKER: Beyond the diagnosis of peripheral arterial disease, AAI provides other interests: it is not only a tool for the functional assessment of lower limb perfusion, but also a marker of local and general atherosclerosis, as well as cardiovascular events.

Symptoms of peripheral arterial disease: A critical review

Peripheral arterial disease (PAD) is an atherosclerotic disease that leads to a narrowing of the arteries in the legs. This narrowing limits the amount of blood able to pass through the arteries. PAD is associated with significant morbidity and mortality, contributes to functional impairment, and can negatively impact quality of life. Claudication, the primary symptom of PAD, arises during activity when the blood and oxygen demand of the working skeletal muscle exceeds supply. The prevalence of claudication in patients with PAD varied from 4.5% to 54.4% in the articles reviewed. Variables that make understanding the symptom experience of PAD difficult include the type of population that research studies target, the wide range of definitions of claudication, and the lack of clear definitions regarding those who experience atypical symptoms or who are asymptomatic. This article reviews the literature related to the assessment, functional impairment, and symptom experience of patients with PAD, including a critique of the methods and findings of these studies. Education of health care professionals and the general public on what is known about PAD functional impairment and the symptom experience is greatly needed. Further research is needed. It is recommended to begin with qualitative research, which could then be used to improve quantitative assessments in those suspected of having PAD.

The effects of continuing medical education credits on physician response rates to a mailed questionnaire

This study investigated whether the opportunity to obtain Continuing Medical Education (CME) credit together with a five-dollar bill increased response rates and questionnaire completion rates in a physician survey involving mailed questionnaires. One thousand, three hundred and fourteen cardiologists, family practitioners, general internists (non-surgeons) and 264 vascular surgeons randomly identified from the American Medical Association database participated. After two, of up to four, questionnaire mailings, the opportunity to obtain CME credit and a five-dollar bill were included with questionnaire mailings. Among non-surgeons, 26.5% responded to pre-incentive mailings and 30.2% of those initially unresponsive replied after the interventions. Among surgeons, 39% responded to pre-incentive mailings and 32.7% of those initially unresponsive replied after the interventions. In conclusion, the opportunity to receive CME credit combined with a small monetary incentive is an effective motivation for physicians participating in a study involving mailed questionnaires.

Mandate for creation of a national peripheral arterial disease public awareness program: an opportunity to improve cardiovascular health

BACKGROUND

There has been increasing recognition of the detrimental effect of peripheral arterial disease (PAD) on the health of Americans, and yet there is no common national program of public PAD education designed to diminish this effect. FORMAT: To heighten awareness of this problem, a 2-day PAD Public Education Strategy Meeting was recently attended by representatives of 17 professional societies and public health associations whose missions support the prevention, diagnosis, treatment, and rehabilitation of vascular diseases. This Public Education Strategy Meeting was intended to provide the rationale and structure to create a national PAD public awareness campaign to diminish the health effect of PAD and to improve cardiovascular outcomes in the United States. This document (1) provides the rationale for creation of a national PAD public education program; (2) reviews the development and success of national hypertension, hypercholesterolemia, and Women's Heart Health public education programs as models of educational efficacy; (3) elucidates how the work of many vascular professionals has led to a national consensus for creation of a national PAD public educational program; (4) provides an overview of the National Heart, Lung, and Blood Institute PAD education meeting; and (5) outlines the "next steps" required to accomplish these goals.

OUTCOME

This meeting achieved consensus that we share responsibility for developing accurate, unified messages to promote PAD awareness and improved care. Participants agreed that the creation of such messages should be linked to plans to disseminate them to all Americans at risk. A consensus was reached that such messages, when commonly created and offered to the public, are most likely to achieve the rewards in better health that all Americans deserve. The Vascular Disease Foundation, a not-for-profit foundation whose mission includes public education about the prevention, diagnosis, treatment, and rehabilitation of PAD, will devote its resources to guide a new coalition in this process and to create a national PAD awareness campaign. During 2003 and 2004, the coalition will create the organizational underpinnings and time line for what will undoubtedly be a multiyear effort.

CONCLUSION

Participants of the Public Education Strategy Meeting agreed to create a broad coalition to develop a National PAD Public Awareness Program, with the objectives to develop and disseminate public education messages on PAD. A successful national PAD education program will contribute to creation of a broader mandate to improve global cardiovascular health in the United States.

Lower limb arterial incompressibility and obstruction in rheumatoid arthritis

BACKGROUND

Despite increased cardiovascular morbidity and mortality in rheumatoid arthritis, the peripheral arteries remain understudied.

OBJECTIVE

To examine the lower limb arteries in age and sex matched, non-smoking subjects with and without rheumatoid arthritis.

METHODS

The ankle-brachial index (ABI) was measured at the posterior tibial and dorsal pedal arteries. Arteries were classified as obstructed with ABI < or =0.9, normal with ABI >0.9 but < or =1.3, and incompressible with ABI >1.3. Multinomial logistic regression was used to estimate differences in ABI between patients and controls, adjusting for cardiovascular risk factors, rheumatoid arthritis manifestations, inflammation markers, and glucocorticoid dose.

RESULTS

234 patients with rheumatoid arthritis and 102 controls were studied. Among the rheumatoid patients, 66 of 931 arteries (7%) were incompressible and 30 (3%) were obstructed. Among the controls, three of 408 arteries (0.7%) were incompressible (p = 0.002) and four (1%) were obstructed (p = 0.06). At the person level, one or more abnormal arteries occurred among 45 rheumatoid patients (19%), v five controls (5%, p = 0.001). The greater frequency of arterial incompressibility and obstruction in rheumatoid arthritis was independent of age, sex, and cardiovascular risk factors. Adjustment for inflammation markers, joint damage, rheumatoid factor, and glucocorticoid use reduced rheumatoid arthritis v control differences. Most arterial impairments occurred in rheumatoid patients with 20 or more deformed joints. This subgroup had more incompressible (15%, p< or =0.001) and obstructed arteries (6%, p = 0.005) than the controls, independent of covariates.

CONCLUSIONS

Peripheral arterial incompressibility and obstruction are increased in rheumatoid arthritis. Their propensity for patients with advanced joint damage suggests shared pathogenic mechanisms.

Prevalence of and risk factors for peripheral arterial disease in the United States: results from the National Health and Nutrition Examination Survey, 1999-2000

BACKGROUND

Peripheral arterial disease (PAD) is associated with significant morbidity and mortality and is an important marker of subclinical coronary heart disease. However, estimates of PAD prevalence in the general US population have varied widely.

METHODS AND RESULTS

We analyzed data from 2174 participants aged 40 years and older from the 1999-2000 National Health and Nutrition Examination Survey. PAD was defined as an ankle-brachial index <0.90 in either leg. The prevalence of PAD among adults aged 40 years and over in the United States was 4.3% (95% CI 3.1% to 5.5%), which corresponds to approximately 5 million individuals (95% CI 4 to 7 million). Among those aged 70 years or over, the prevalence was 14.5% (95% CI 10.8% to 18.2%). In age- and gender-adjusted logistic regression analyses, black race/ethnicity (OR 2.83, 95% CI 1.48 to 5.42) current smoking (OR 4.46, 95% CI 2.25 to 8.84), diabetes (OR 2.71, 95% CI 1.03 to 7.12), hypertension (OR 1.75, 95% CI 0.97 to 3.13), hypercholesterolemia (OR 1.68, 95% CI 1.09 to 2.57), and low kidney function (OR 2.00, 95% CI 1.08 to 3.70) were positively associated with prevalent PAD. More than 95% of persons with PAD had 1 or more cardiovascular disease risk factors. Elevated fibrinogen and C-reactive protein levels were also associated with PAD.

CONCLUSIONS

This study provides nationally representative prevalence estimates of PAD in the United States, revealing that PAD affects more than 5 million adults. PAD prevalence increases dramatically with age and disproportionately affects blacks. The vast majority of individuals with PAD have 1 or more cardiovascular disease risk factors that should be targeted for therapy.

Benefits of antithrombotic therapy after infrainguinal bypass grafting: a meta-analysis

PURPOSE

We performed a meta-analysis to ascertain the benefits of antithrombotic therapy for maintaining the patency of vascular grafts following lower extremity bypass operations.

METHODS

We identified articles using MEDLINE and hand searches of relevant journals for randomized clinical trials that compared the use of antithrombotic therapy with control or placebo therapy. Random-effects (DerSimonian and Laird) analyses were used to determine the risk of graft occlusion following lower extremity bypass operations. We also assessed the odds of secondary outcomes, such as myocardial infarction, cerebrovascular accident, all-cause mortality, and bleeding.

RESULTS

Sixteen articles met the inclusion criteria of a randomized trial of antithrombotic therapy for the patency of vascular grafts; six were excluded because the analyses involved repeat surgeries or lacked a control group. Of the 10 studies included in the final analysis, seven compared antiplatelet agents with placebo or control, and three compared anticoagulant agents with placebo or control. The 10 studies were homogeneous in spite of differing durations of follow-up. The odds of graft occlusion in the treated group was half that in the placebo or control group. The odds ratio was 0.46 (95% confidence interval [CI]: 0.32 to 0.66) for the 10 studies that reported outcomes at 12 months or longer, 0.50 (95% CI: 0.29 to 0.87) in the five studies with 12-month rates; and 0.58 (95% CI: 0.39 to 0.88) at 24 months.

CONCLUSION

Antithrombotic therapy decreases the risk of graft occlusion after a vascular operation by about 50% at 12 months and is still protective at 24 months after the operation.

Vascular Endothelial Growth Factor Overexpression in Ischemic Skeletal Muscle Enhances Myoglobin Expression In Vivo

Therapeutic angiogenesis using vascular endothelial growth factor (VEGF) is considered a promising new therapy for patients with arterial obstructive disease. Clinical improvements observed consist of improved muscle function and regression of rest pain or angina. However, direct evidence for improved vascularization, as evaluated by angiography, is weak. In this study, we report an angiogenesis-independent effect of VEGF on ischemic skeletal muscle, ie, upregulation of myoglobin after VEGF treatment. Mice received intramuscular injection with adenoviral VEGF-A or either adenoviral LacZ or PBS as control, followed by surgical induction of acute hindlimb ischemia at day 3. At day 6, capillary density was increased in calf muscle of Ad.VEGF-treated versus control mice ( P <0.01). However, angiographic score of collateral arteries was unchanged between Ad.VEGF-treated and control mice. More interestingly, an increase in myoglobin was observed in Ad.VEGF-treated mice. Active myoglobin was 1.5-fold increased in calf muscle of Ad.VEGF-treated mice ( P ≤0.01). In addition, the number of myoglobin-stained myofibers was 2.6-fold increased in Ad.VEGF-treated mice ( P =0.001). Furthermore, in ischemic muscle of 15 limb amputation patients, VEGF and myoglobin were coexpressed. Finally, in cultured C2C12 myotubes treated with rhVEGF, myoglobin mRNA was 2.8-fold raised as compared with PBS-treated cells ( P =0.02). This effect could be blocked with the VEGF receptor tyrosine kinase inhibitor SU5416. In conclusion, we show that VEGF upregulates myoglobin in ischemic muscle both in vitro and in vivo. Increased myoglobin expression in VEGF-treated muscle implies an improved muscle oxygenation, which may, at least partly, explain observed clinical improvements in VEGF-treated patients, in the absence of improved vascularization.

Prevalence, risk factors and cardiovascular comorbidity of symptomatic peripheral arterial disease in Italy

The epidemiology of peripheral arterial disease (PAD) has been studied almost exclusively in northern European and northern American populations. We report the first survey in Italy to describe the prevalence of symptomatic PAD and clinical correlates. From the lists of seven general practitioners, all subjects aged 40-80 years (n = 4352) received a Rose Questionnaire (RQ). In those reporting pain in the leg while walking, which did not disappear while continuing to walk (n = 760), Doppler examination was performed. PAD was defined by ankle/brachial < or = 0.90, or reduced flow velocity. The prevalence of symptomatic PAD was 1.6% (2.4% in men, 0.9% in women). For each PAD patient, three controls matched for sex and age were randomly selected. At the multivariate analysis, smoking, diabetes and hypertension were significantly associated with PAD. A coexistent cardiovascular disease was found in 34% of patients and 11% of controls (P < 0.001). Only PAD was shown to be independently associated with a previous cardiovascular event. Although symptomatic, 45% of the patients were unaware of their condition. In conclusion, prevalence and cardiovascular comorbidity of symptomatic PAD in Italy seem to be lower than in other western countries. The finding that PAD was unrecognised in about 50% of affected individuals implies that a large proportion of PAD population is not given preventive therapy, so remaining at high cardiovascular risk. Thus, there is need to alert general practitioners to this topic.

Lead, Cadmium, Smoking, and Increased Risk of Peripheral Arterial Disease

BACKGROUND

Lead and cadmium exposure may promote atherosclerosis, although the cardiovascular effects of chronic low-dose exposure are largely unknown. The objective of the present study was to evaluate the association between blood levels of lead and cadmium and peripheral arterial disease.

METHODS AND RESULTS

We analyzed data from 2125 participants who were > or =40 years of age in the 1999 to 2000 National Health and Nutrition Examination Survey (NHANES). Peripheral arterial disease was defined as an ankle brachial index <0.9 in at least 1 leg. Lead and cadmium levels were measured by atomic absorption spectrometry. After adjustment for demographic and cardiovascular risk factors, the ORs of peripheral arterial disease comparing quartiles 2 to 4 of lead with the lowest quartile were 1.63 (95% CI, 0.51 to 5.15), 1.92 (95% CI, 0.62 to 9.47), and 2.88 (95% CI, 0.87 to 9.47), respectively (P for trend=0.02). The corresponding ORs for cadmium were 1.07 (95% CI, 0.44 to 2.60), 1.30 (95% CI, 0.69 to 2.44), and 2.82 (95% CI, 1.36 to 5.85), respectively (P for trend=0.01). The OR of peripheral arterial disease for current smokers compared with never smokers was 4.13. Adjustment for lead reduced this OR to 3.38, and adjustment for cadmium reduced it to 1.84.

CONCLUSIONS

Blood lead and cadmium, at levels well below current safety standards, were associated with an increased prevalence of peripheral arterial disease in the general US population. Cadmium may partially mediate the effect of smoking on peripheral arterial disease.

Peripheral Arterial Disease in African Americans: Clinical Characteristics, Leg Symptoms, and Lower Extremity Functioning

OBJECTIVES

The describe peripheral arterial disease (PAD) in African Americans, and compare findings in African Americans and whites with PAD.

DESIGN

Cross-sectional.

SETTING

Three academic medical centers.

PARTICIPANTS

Three hundred sixty-six whites and 76 African Americans with PAD (as defined by an ankle brachial index (ABI) <0.90) aged 55 and older identified from lower extremity arterial studies performed between 1996 and the fall of 1999.

MEASUREMENTS

Comprehensive medical interview, body mass index, and neuropathy score. Functional measurements included the 6-minute walk distance, 4-m walking velocity, and the summary performance score.

RESULTS

Age- and sex-adjusted results showed that African Americans had a lower mean ABI than whites (0.60 vs 0.66, P=.001), were less likely to be college graduates (13.7% vs 44.4%, P<.001), and had nearly twice the prevalence of diabetes mellitus (46.8% vs 28.0%, P=.001). After adjusting for age, sex, education level, and ABI, African Americans had a higher prevalence of no exertional leg pain (28.0% vs 18.2%, P=.044) and leg pain with exertion and rest (30.0% vs 17.3%, P=.023). African Americans had a shorter 6-minute walk distance (989 vs 1,156 ft, P<.001), a slower normal-pace 4-m walking velocity (0.79 vs 0.89 m/s, P<.001), a slower fast-pace 4-m walking velocity (1.12 vs 1.20 m/s, P=.012), and a lower summary performance score (8.8 vs 9.6, P=.018) than whites. These differences in functioning were attenuated after adjusting for age, sex, ABI, education, and leg symptoms.

CONCLUSION

Poorer lower extremity functioning in African Americans was largely explained by differences in leg symptoms and, to a somewhat lesser degree, lower ABI levels and poorer education in African Americans than in whites. Further study is needed to determine whether these findings affect racial treatment disparities and poorer outcomes previously reported in African Americans than in whites with PAD.

Arterial Insufficiency and Ulceration: Diagnosis and Treatment Options

PURPOSE

To provide physicians and nurses with an overview of the pathophysiology, assessment, diagnosis, and treatment of arterial insufficiency and ulceration.

TARGET AUDIENCE

This continuing education activity is intended for physicians and nurses with an interest in managing patients with arterial insufficiency and ulceration.

OBJECTIVES

After reading the article and taking the test, the participant will be able to: 1. Describe the anatomy and physiology of the lower extremity arterial system and the pathophysiology of arterial ulcers. 2. Describe the assessment and diagnosis of arterial insufficiency and ulceration. 3. Identify treatment options and teaching considerations for patients with arterial insufficiency and ulceration.

Dietary sodium restriction rapidly improves large elastic artery compliance in older adults with systolic hypertension

We determined the temporal effects of dietary sodium restriction on large elastic artery compliance and systolic blood pressure (SBP) in 12 untreated, older (64+/-2 years) men and women (6 each) with stage 1 systolic hypertension. After baseline measurements subjects were assigned to 4 weeks of low or normal sodium intake (randomized, crossover design). Urinary sodium excretion was reduced by 60% by the end of week 1 of sodium restriction (54+/-11 mmol/d, P<0.01) versus baseline (135+/-14). Compared with baseline (0.11+/-0.01 mm/mm Hg), carotid artery compliance was increased by 27% (to 0.14+/-0.02, P<0.05) at the end of week 1 of sodium restriction, attaining peak levels by week 2 (+46%, to 0.16+/-0.02, P<0.01). Similarly, supine resting brachial artery SBP was reduced by >5 mm Hg by week 1 of sodium restriction, attaining peak reductions by week 2 (-12 mm Hg, P<0.01 versus baseline). The 24-hour ambulatory SBP was approximately 3 mm Hg lower at week 1 of sodium restriction and approximately 6 mm Hg lower by week 2 (P<0.01 versus baseline). The reductions in resting SBP from baseline to week 2 of sodium restriction were strongly related to the corresponding increases in carotid compliance (r=0.80, P<0.01). Urinary sodium excretion, carotid artery compliance, and SBP were not different during normal sodium intake versus baseline. Other subject characteristics were not different across conditions. Sodium restriction rapidly improves large elastic artery compliance in older adults with stage 1 systolic hypertension. These improvements in central arterial compliance appear to be a key mechanism in the rapid normalization of SBP by sodium restriction in these patients.

Long-term results of peripheral arterial disease rehabilitation

PURPOSE

Although the Peripheral Arterial Disease Rehabilitation Program (PADRx) improves walking ability and quality of life over brief periods of follow-up, the long-term durability of results has not been established. This study examined functional status, walking ability, and quality of life in patients several months after completion of a 12-week PADRx.

METHODS

Patients who completed a PADRx were eligible for participation. A Medical Outcomes Study 36-Item Short Form (SF-36), Walking Impairment Questionnaire (WIQ), and physical activity questionnaire were administered by telephone. A progressive treadmill test was performed on-site.

RESULTS

Of 63 eligible patients, 14 were lost to follow-up, 11 refused participation, and four died. Thirty-four patients had completed PADRx 20 to 80 months previously (mean, 48.2 +/- 13.7 months), and completed the phone survey. Fifteen patients reported exercising a minimum of 60 min/wk for 3 months (EX group), and 19 had not exercised in the preceding 3 months (SED group). Self-reported SF-36 values were significantly different between the EX and SED groups for Physical Function (43.3 +/- 8.2 vs 34.2 +/- 7.8), Role-Physical Function (41.2 +/- 7.7 vs 32.8 +/- 9.2), and Bodily Pain (46.9 +/- 8.8 vs 38.9 +/- 7.1), as well as the Physical Composite (43.5 +/- 6.5 vs 34.0 vs 5.8) domains of the SF-36. Similarly the WIQ demonstrated significant differences in Walking Distance (46.8 +/- 36.2 vs 7.8 +/- 9.4), Walking Speed (47.5 +/- 32.6 vs 14.5 +/- 13.9), and Stair Climbing (60.6 +/- 36.6 vs 37.1 +/- 27.6), favoring the EX group. Sixteen patients, equally distributed between the EX and SED groups, completed the progressive treadmill test. Both groups had experienced improvement (P <.05) in claudication pain time and maximal walking time after completing the 12-week supervised program. The EX group maintained increased claudication pain time of 121% and maximum walking time of 109% over baseline, whereas the SED group values had returned to baseline (P <.05).

CONCLUSIONS

Patients with claudication realize symptomatic and functional improvement with supervised exercise programs. Those who continue to exercise will potentially maintain these benefits and experience improved health-related quality of life.

Assessment and management of patients with venous, arterial, and diabetic/neuropathic lower extremity wounds

Most healthcare providers recognize that management of lower extremity wounds presents a difficult challenge. These chronic wounds significantly impact the quality of life for individuals and have implications for costs and utilization of healthcare resources. Lower extremity wounds can be due to a myriad of different diseases, but the primary causes are chronic venous insufficiency, lower extremity arterial disease, and diabetes/neuropathy. Differential assessment is necessary prior to implementation of management strategies in order to address the etiology and pathogenesis factors that are related to each type of leg wound. This article presents an overview of the risk and predisposing factors for venous, arterial, and diabetic/neuropathic wounds. Additionally, it addresses issues of differential assessment including typical locations, common clinical characteristics, typical wound appearance, key management issues, considerations for alternative treatments, collaborative care, and patient/family education.

Preclinical models of human peripheral arterial occlusive disease: implications for investigation of therapeutic agents

Peripheral arterial occlusive disease (PAOD) is now recognized as a combination of clinical syndromes that are associated with significant morbidity and mortality. The primary pathophysiology of PAOD is impaired perfusion to the lower extremity. Effective pharmacotherapy designed to increase perfusion in PAOD is lacking, and revascularization options are suboptimal. New and more efficacious therapies that improve blood flow are definitely needed, and thus designing, describing, and validating these new therapies in preclinical PAOD models will be essential. This study describes the various preclinical PAOD models presently in use, correlates the models to human PAOD, and reviews the available end points that can be used to detect a response to therapy.

Aortoiliac Insufficiency: Long-term Experience with Stent Placement for Treatment

PURPOSE

To establish and report the authors' experience with the long-term outcomes of aortoiliac stent placement for treatment of chronic lower-extremity ischemia.

MATERIALS AND METHODS

Stents were placed in 505 arterial segment lesions in 365 patients who presented with symptoms of chronic leg ischemia between February 1992 and March 2001. The 505 treated lesions were 88 occlusions and 417 stenoses. Indications for stent placement were claudication in 312 (62%), rest pain in 107 (21%), ulcer in 67 (13%), and gangrene in 19 (4%) arterial segments. Patients were followed up for up to 105 months (mean, 33 months +/- 27 [SD]).

RESULTS

Hemodynamic success was achieved in 484 (98%) of the 496 limbs for which postprocedural translesion pressure gradients were available. Mean ankle-brachial indexes improved from 0.53 +/- 0.25 to 0.79 +/- 0.23 (P <.001). Major complications were seen in 24 (7%) patients. Two patients (0.5%) died within 30 days after stent placement. Twenty (6%) of 355 patients underwent aortic or iliac bypass surgery during the follow-up period. Eight years after stent placement, primary patency was 74%; primary assisted patency, 81%; and secondary patency, 84%. Variables associated with better patency included stenosis (rather than occlusion), shorter lesion length, older age, and limb-threatening ischemia. At the last follow-up examination, 74% of the 466 limbs for which follow-up clinical status data were available were asymptomatic, 22% were associated with claudication, 3% were associated with rest pain, and 1% were associated with ischemic tissue loss. Five patients underwent amputation on the ipsilateral side after stent placement.

CONCLUSION

Findings from long-term experience with aortoiliac stent placement for treatment of chronic lower-extremity ischemia confirmed the procedure to be a durable, low-risk revascularization option.

Peripheral Arterial Disease: Pathophysiology, Risk Factors, and Role of Antithrombotic Therapy

OBJECTIVE

To provide an overview of the impact of peripheral arterial disease (PAD) and the steps that can be taken to reduce its burden through greater awareness of the disease, improved diagnosis, and better treatment, with emphasis on the use of antiplatelet agents.

DATA SOURCES

Recent (1990-2003) published scientific literature, as identified by the author through Medline searches, using the terms peripheral arterial disease, atherothrombosis, pathophysiology, risk factors, treatment, clinical trials, and reviews on treatment.

STUDY SELECTION

Recent systematic English-language review articles and reports of controlled randomized clinical trials were screened for inclusion.

DATA SYNTHESIS

PAD is a distinct atherothrombotic syndrome marked by stenosis and occlusion of peripheral arterial beds, typically those in the lower extremities. Symptoms range from intermittent claudication (IC) during exercise to peripheral limb ischemia requiring limb amputation. IC, the most common symptom, is experienced by 2% to 3% of men and 1% to 2% of women aged 60 years and older. Despite its recognition as a major atherothrombotic risk factor, PAD is not widely appreciated by clinicians, and most cases remain undiagnosed. Asymptomatic PAD, as indicated by a reduced ankle brachial systolic pressure index, should alert the health care provider to the presence of diffuse atherothrombotic disease and need for treatment. Risk factors for development and progression of PAD include smoking, hypertension, diabetes, hyperlipidemia, and physical inactivity. The aim of pharmacotherapy is to improve the symptoms of PAD (especially IC), defer onset of limb-threatening ischemia, and improve long-term survival. Successful treatment strategies include risk factor modification, particularly smoking cessation; initiation of regular exercise; control of hypertension, diabetes, and hyperlipidemia; and use of antiplatelet agents to reduce the risk of atherothrombotic events. Available data suggest that aspirin reduces morbidity and mortality in PAD, while clopidogrel reduces the risk of atherothrombotic events such as myocardial infarction and stroke in these patients.

CONCLUSION

Increased awareness among members of the health care community about the prevalence of PAD and benefits associated with risk-factor reduction and antiplatelet therapy could produce substantial decreases in the burden of this disease.

Outcome of Conservative Therapy of Patients with Severe Intermittent Claudication

BACKGROUND

Intermittent claudication due to peripheral artery disease (PAD) can be treated conservatively, or by revascularization.

OBJECTIVES

To assess the short-term outcome of conservatively-treated claudicants, and determine predictors for clinical improvement. Design. A retrospective cohort study.

METHODS

We evaluated Fontaine stage, walking distance and ankle brachial index (ABI) at baseline and after median 9 months (interquartile range (IQR) 6-24) in 181 patients with severe claudication.

RESULTS

We found clinical improvement by at least one Fontaine stage in 38 patients (21%) with an increased walking distance from baseline median 100 m (IQR 50-150) to follow-up median 650 m (IQR 300 to unlimited; p<0.001), but without changes in ABI (median 0.57, IQR 0.48-0.73 vs. median 0.54, IQR 0.45-0.81; p=0.10). One hundred and thirty-eight patients (76%) remained clinically and hemodynamically stable. A worsening of the clinical stage but without amputation was recorded in five patients (3%). Female gender (hazard ratio (HR) 0.51, p=0.052), diabetes (HR 0.35, p=0.020), and baseline ABI below 0.44 (HR 0.31, p=0.019) were associated with a reduced probability of clinical improvement.

CONCLUSION

Certain patients with intermittent claudication show substantial clinical improvement with conservative medical therapy, despite any lack of hemodynamic improvement. Given the low number of patients with clinical deterioration in the short term, primarily conservative therapy should be the preferred initial option for most claudicants.

Usefulness of an abnormal ankle-brachial index to predict presence of coronary artery disease in African-Americans

We sought to determine the role of an abnormal ankle-brachial index (ABI) in an African-American population with suspected coronary artery disease (CAD) referred for diagnostic coronary angiography. In this population, an ABI < or =0.90 predicted the presence of > or =3-vessel or left main CAD with a sensitivity of 85% and specificity of 77%. However, a normal ABI did not predict absence of 1- or 2-vessel CAD. These results suggest that in this population, the ABI can be used to increase the pretest probability of severe CAD.