Standard exercise test to assess peripheral arterial disease

2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease" provides recommendations to guide clinicians in the treatment of patients with lower extremity peripheral artery disease across its multiple clinical presentation subsets (ie, asymptomatic, chronic symptomatic, chronic limb-threatening ischemia, and acute limb ischemia).

METHODS

A comprehensive literature search was conducted from October 2020 to June 2022, encompassing studies, reviews, and other evidence conducted on human subjects that was published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through May 2023 during the peer review process, were also considered by the writing committee and added to the evidence tables where appropriate.

STRUCTURE

Recommendations from the "2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with peripheral artery disease have been developed.

2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease" provides recommendations to guide clinicians in the treatment of patients with lower extremity peripheral artery disease across its multiple clinical presentation subsets (ie, asymptomatic, chronic symptomatic, chronic limb-threatening ischemia, and acute limb ischemia).

METHODS

A comprehensive literature search was conducted from October 2020 to June 2022, encompassing studies, reviews, and other evidence conducted on human subjects that was published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through May 2023 during the peer review process, were also considered by the writing committee and added to the evidence tables where appropriate.

STRUCTURE

Recommendations from the "2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with peripheral artery disease have been developed.

Combination of Exercise Testing Criteria to Diagnose Lower Extremity Peripheral Artery Disease

Objectives: Nothing is known about the interest of the combination of exercise tests to diagnose Lower-extremity Peripheral Artery Disease (LEPAD). The aim of this study was to assess if combining exercise testing criteria [post-exercise Ankle-Brachial Index (ABI) + exercise-oximetry (exercise-TcPO2)] improves the detection of lower limbs arterial stenoses as compared with post-exercise ABI using American Heart Association (AHA) criteria, or exercise-TcPO2 alone. Material and Methods: In a prospective monocentric study, consecutive patients with exertional-limb pain and normal resting-ABI referred to our vascular center (Rennes, France) were assessed from May 2016 to February 2018. All included patients had a computed tomography angiography (CTA), a resting-ABI, a post-exercise ABI and an exercise-TcPO2. AHA post-exercise criteria, new validated post-exercise criteria (post-exercise ABI decrease ≥18.5%, post-exercise ABI decrease <0.90), and Delta from Rest of Oxygen Pressure (Total-DROP) ≤-15mmHg (criterion for exercise-TcPO2) were used to diagnose arterial stenoses ≥50%. For the different combinations of exercise testing criteria, sensitivity or specificity or accuracies were compared with McNemar's test. Results: Fifty-six patients (mean age 62 ± 11 years old and 84% men) were included. The sensitivity of the combination of exercise testing criteria (post-exercise ABI decrease ≥18.5%, or post-exercise ABI decrease <0.90 or a Total-DROP ≤-15mmHg) was significantly higher (sensitivity = 81% [95% CI, 71-92]) than using only one exercise test (post-exercise AHA criteria (sensitivity = 57% [43-70]) or exercise-TcPO2 alone (sensitivity = 59% [45-72]). Conclusions: Combination of post-exercise ABI with Exercise-TcPO2 criteria shows better sensitivity to diagnose arterial stenoses compared with the AHA post-exercise criteria alone or Exercise-TcPO2 criteria used alone. A trend of a better accuracy of this combined strategy was observed but an external validation should be performed to confirm this diagnostic strategy.

Exercise testing criteria to diagnose lower extremity peripheral artery disease assessed by computed-tomography angiography

BACKGROUND

The sensitivity and specificity of exercise testing have never been studied simultaneously against an objective quantification of arterial stenosis. Aims were to define the sensitivity and specificity of several exercise tests to detect peripheral artery disease (PAD), and to assess whether or not defined criteria defined in patients suspected of having a PAD show a difference dependent on the resting ABI.

METHODS

In this prospective study, consecutive patients with exertional limb pain referred to our vascular center were included. All patients had an ABI, a treadmill exercise-oximetry test, a second treadmill test (both 10% slope; 3.2km/h speed) with post-exercise pressures, and a computed-tomography-angiography (CTA). The receiver-operating-characteristic curve was used to define a cut-off point corresponding to the best area under the curve (AUC; [CI95%]) to detect arterial stenosis ≥50% as determined by the CTA.

RESULTS

Sixty-three patients (61+/-11 years-old) were included. Similar AUCs from 0.72[0.63-0.79] to 0.83[0.75-0.89] were found for the different tests in the overall population. To detect arterial stenosis ≥50%, cut-off values of ABI, post-exercise ABI, post-exercise ABI decrease, post-exercise ankle pressure decrease, and distal delta from rest oxygen pressure (DROP) index were ≤0.91, ≤0.52, ≥43%, ≥20mmHg and ≤-15mmHg, respectively (p<0.01). In the subset of patients with an ABI >0.91, cut-off values of post-exercise ABI decrease (AUC = 0.67[0.53-0.78]), and DROP (AUC = 0.67[0.53-0.78]) were ≥18.5%, and ≤-15mmHg respectively (p<0.05).

CONCLUSION

Resting ABI is as accurate as exercise testing in patients with exertional limb pain. Specific exercise testing cut-off values should be used in patients with normal ABI to diagnose PAD.

[Diagnosis of lower limb peripheral artery disease]

Lower limb peripheral artery disease is highly prevalent worldwide and in France. Three different stages can be found: asymptomatic stage, exercise ischemia stage, rest ischemia stage. This review based on current recommendations presents how to diagnose the different stages (Ankle brachial index, Toe-brachial index, oxymetry at rest and exercise oxymetry) in order to manage these patients.

Noninvasive Peripheral Artery Disease Screening Tools: A Deficient Knowledge among French Vascular Residents from 4 Medical Schools

BACKGROUND

Ankle-brachial index (ABI) at rest, postexercise ABI, and toe-brachial index (TBI) are essential diagnostic tools recommended for peripheral artery disease (PAD) diagnosis. Our study investigates the level of knowledge on these 3 tests among vascular medicine residents from 4 French medical schools in France.

METHODS

We included 19 vascular medicine residents in a cross-sectional study. During an annual obligatory seminar, all residents accepted to fill 3 questionnaires concerning knowledge about these 3 tests.

RESULTS

All residents accepted to fill 3 questionnaires. None of the residents correctly knows how to perform all pressure measurements (ABI, postexercise ABI, and TBI). Two residents had the knowledge to perform the whole ABI at rest procedure, whereas no resident had the knowledge to perform neither the postexercise ABI (P = 0.48) nor the TBI (P = 0.48). Twelve residents correctly completed the question regarding the interpretation of ABI at rest, whereas 2 correctly completed the postexercise ABI question (P = 0.001) and 4 the TBI question (P = 0.02). The number of residents who have performed more than 20 measurements is higher regarding ABI at rest than postexercise ABI and TBI (84%, 5%, and 37% respectively; P < 0.001 and P = 0.006 respectively) and significantly less often in postexercise ABI than TBI (5% vs. 37%; P = 0.04).

CONCLUSIONS

This study shows for the first time that residents' knowledge of pressure measurements (resting-ABI, postexercise ABI, and TBI) of 4 French medical school are insufficient although the importance of pressure measurement has been strongly highlighted by the newly released PAD guidelines (2016) for PAD diagnosis.

2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines

Since 1980, the American College of Cardiology (ACC) and American Heart Association (AHA) have translated scientific evidence into clinical practice guidelines with recommendations to improve cardiovascular health. These guidelines, based on systematic methods to evaluate and classify evidence, provide a cornerstone of quality cardiovascular care.

In response to reports from the Institute of Medicine1 ,2 and a mandate to evaluate new knowledge and maintain relevance at the point of care, the ACC/AHA Task Force on Clinical Practice Guidelines (Task Force) modified its methodology.3 –5 The relationships among guidelines, data standards, appropriate use criteria, and performance measures are addressed elsewhere.5

2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines

Since 1980, the American College of Cardiology (ACC) and American Heart Association (AHA) have translated scientific evidence into clinical practice guidelines with recommendations to improve cardiovascular health. These guidelines, based on systematic methods to evaluate and classify evidence, provide a cornerstone of quality cardiovascular care.

In response to reports from the Institute of Medicine1 ,2 and a mandate to evaluate new knowledge and maintain relevance at the point of care, the ACC/AHA Task Force on Clinical Practice Guidelines (Task Force) modified its methodology.3 –5 The relationships among guidelines, data standards, appropriate use criteria, and performance measures are addressed elsewhere.5

The Role of Ultrasound in Lower Extremity Wound Management

Imaging and hemodynamic information are essential in determining the etiology of lower extremity wounds. Ultra- sound offers a noninvasive method of studying vessel walls and measuring blood flow, thereby providing reliable diagnostic data. This article reviews the role of ultrasound in the management of the lower extremity wound.

Discordant Diagnosis of Lower Extremity Peripheral Artery Disease Using American Heart Association Postexercise Guidelines

To determine whether postexercise criteria for peripheral artery disease (PAD) diagnosis recommended by the American Heart Association (AHA) identifies the same group of PAD patients.Diagnosis of PAD is performed using ankle-brachial index at rest (resting-ABI). When resting-ABI is not contributive, an AHA scientific statement recommend to use 1 of 2 following criteria: a postexercise ABI decrease of greater than 20% or a postexercise ankle pressure decrease of greater than 30 mm Hg.Between 1996 and 2012, 31,663 consecutive patients underwent lower-extremity arterial study at Mayo Clinic. Among them, only unique patients who had exercise treadmill testing were analyzed. In this retrospective analysis, resting-ABI, postexercise ABI, and postexercise decrease of ankle pressure measured at 1-minute were measured in each patient. We conducted an analysis of agreement between postexercise criteria expressing the agreement separately for the positive and the negative ratings. Twelve thousand three hundred twelve consecutive patients were studied with a mean age of 67 ± 12 years, 61% male. According to resting-ABI, 4317 (35%) patients had PAD. In the whole population, if a clinician diagnoses "PAD" with 1 postexercise criterion, the probability that other clinicians would also diagnose "PAD" is 74.3%. If a clinician diagnoses "no PAD", the probability that other clinicians would also diagnose "no PAD" is 82.4%. In the patients to be of potential benefit from treadmill test when the resting-ABI > 0.90, if a clinician diagnoses "PAD" with 1 postexercise criterion, the probability that other clinicians would also diagnose "PAD" is 58.4% whereas if a clinician diagnoses "no PAD," the probability that other clinicians would also diagnose "no PAD" is 87.5%.Postexercise criteria do not identify the same group of PAD patients. In our opinion, postexercise criteria to define PAD deserve additional study.

Exercise-ankle brachial pressure index with one-minute treadmill walking in patients on maintenance hemodialysis

BACKGROUND

The ankle-brachial pressure index (ABI) is widely used as a standard screening method for arterial occlusive lesion above the knee. However, the sensitivity of ABI is low in hemodialysis (HD) patients. Exercise stress (Ex-ABI) may reduce the false negative results.

PATIENTS AND METHODS

After measuring resting ABI and toe-brachial pressure index (TBI), ankle pressure and ABI immediately after walking (Post-AP, Post-ABI) were measured using one-minute treadmill walking in 52 lower limbs of 26 HD patients. The definition of peripheral arterial occlusive disease (PAD) required an ABI value of less than 0.90, TBI value of less than 0.60, and decrease of more than 15% of the Post-ABI value and 20 mmHg of Post-AP in Ex-ABI. Computed tomographic angiography (CTA) was performed in 32 lower limbs of 16 HD patients. PAD is defined as presence of stenosis of more than 75% in the case of lesions from an iliac artery to knee on CTA.

RESULTS

The accuracy of Ex-ABI (Sensitivity, 85.7%; Specificity, 77.7%) was higher than those of ABI (Sensitivity, 42.9%; Specificity, 83.3%) or TBI (Sensitivity, 78.6%; Specificity, 61.1%).

CONCLUSION

Ex-ABI with one-minute treadmill walking is the most useful tool for the screening of arterial occlusive lesions above the knee in maintenance HD patients.

A prospective randomized controlled study with intermittent mechanical compression of the calf in patients with claudication

OBJECTIVES

The study tested the feasibility of using a new portable mechanical compression device for the treatment of claudication. The device applies intermittent non-pneumatic mechanical compression (IMC) to the calf. It was hypothesized that it can offer a low-cost convenient option for patients and achieve good compliance and improved clinical outcomes.

METHODS

Thirty patients were enrolled in a randomized controlled single blind study. Fourteen patients were assigned to active IMC. Sixteen control patients continued with medical treatment alone. Outcomes were recorded at baseline, after one month, three months, and six months. The study examined changes in exercise tolerance using Initial Claudiacation Distance (ICD) and Absolute Claudiaction Distance (ACD) as well as ankle-brachial index at rest (ABI-r) and post-exercise (ABI-pe). All patients had stable claudication due to peripheral arterial disease (PAD) and were already under best medical treatment (BMT). To be eligible for inclusion, patients had to be between the ages of 50 and 75 years, had to have stable claudication with an absolute claudication distance >40 meters but <300 meters on a standardized treadmill stress test (3.8 km/h at a 10% grade), have a resting ABI in the affected limb <0.8 with a drop of at least 0.15 following exercise, in whom surgical intervention was not expected for at least three months. Fourteen patients were assigned to active IMC consisting of compressions 65 mm Hg in amplitude, applied for three 3-second compressions/minute, two hours/day for three months. Sixteen control patients continued with BMT alone.

RESULTS

One month after treatment, ICD increased by 66% (P = .001), ACD increased by 51.75% (P = .005), and ABI-pe increased by 42% (P = .01). Treatment effects were maintained or further improved after three months. ABI-r did not increase at any time. Compliance exceeded 80%. Three months following cessation of therapy, claudication distances and ABI-pe did not decrease significantly.

CONCLUSIONS

We concluded that the use of IMC of the calf for three months increased claudication distances and led to objective improvements in ABI-pe. Intermittent mechanical compression may be a useful approach to patients with continued claudication despite standard medical treatment.

Evaluation of the one-minute exercise test to detect peripheral arterial disease

BACKGROUND

Asymptomatic peripheral arterial disease (PAD) is common amongst the elderly and is a risk factor for cardiovascular morbidity and mortality. PAD can be assessed by non-invasive tests such as the ankle/brachial pressure index (ABPI) at rest and Doppler flow velocity (DFV) scanning, but these tests may underestimate the prevalence of PAD. The aim of this study was to estimate the added value, for the detection of PAD, of the one-minute exercise test, defined as positive if the drop of the ankle systolic pressure was more than 30 mmHg. We also investigated whether the combination of the ABPI at rest and the one-minute exercise test could replace DFV scanning.

MATERIALS AND METHODS

We studied this in a random sample (n = 631) of a 50- to 75-year-old population.

RESULTS

Of these subjects 11% (66/631) had an abnormal ABPI (< 0.9) and 16% (102/631) had an abnormal DFV curve. Of this sample 72% of the subjects performed a one-minute exercise test. Of all subjects 6% (27/451) had an abnormal ABPI (< 0.9) and 12% (54/451) had an abnormal DFV curve. The one-minute exercise test revealed seven cases of PAD (beyond the 67 already identified) which were not detected by an abnormal ABPI at rest and/or DFV scanning. As a result the prevalence of PAD increased by 2%. All patients with an aortoiliac or femoropopliteal obstruction had an ABPI at rest < 0.9. The sensitivity of the combination of the ABPI at rest and the one-minute exercise test to detect abnormal DFV curves was low for crural obstructions.

CONCLUSION

The one-minute exercise test slightly improves the detection of peripheral arterial disease in the general population.

Supervised Exercise Training for Intermittent Claudication: Lasting Benefit at Three Years

OBJECTIVES

To assess the long-term outcome of supervised exercise training for intermittent claudication.

METHODS

A prospective study was undertaken of all patients referred to a single centre with intermittent claudication (>46 m). Patients underwent supervised exercise training twice weekly for 10 weeks, with regular follow-up to 3 years. Actual Claudication Distance (ACD), Maximum Walking Distance (MWD) and ankle-brachial pressure indices (ABPI) were measured.

RESULTS

In 202 patients the initial median ACD and MWD were 112 m and 197 m. Following exercise therapy both the median ACD and MWD increased to 266 m and 477 m at three months, increases of 237% and 242% respectively (p<0.001). At three years the median ACD and MWD were 250 m and 372 m, increases of 223% and 188% respectively (p<0.001). There was no significant change in ACD or MWD at 3 months compared to 1, 2 or 3 years. ABPI remained unchanged throughout.

CONCLUSIONS

Supervised exercise training has long term benefit in patients with intermittent claudication. Results seen at 12 weeks are sustained at three years.

Peripheral arterial disease in diabetic patients selected from a primary care setting: Implications for nursing practice

Although the care of patients with diabetes is increasingly provided in primary care, there is relatively little information on the prevalence and long-term progression of asymptomatic peripheral arterial disease (PAD) in diabetic populations selected from primary care settings. The aims of this study were to investigate prevalence and progression of PAD in 146 diabetic patients, and to compare mortality with 113 nondiabetic controls over a 7-year period. The prevalence of PAD in individual pedal arteries varied between 28.6% in the right posterior tibial artery to 48.8% in the left peroneal artery. During the 7-year period, 34.25% of the diabetic subjects died, and 17.5% moved to other locations. Of the remaining 70 patients, 35 (50%) showed no change in ankle-brachial index and 35 (50%) did show change. Comparison of risk factors between those who did and did not show evidence of progression revealed (1) a strong, significant, independent association between hyperglycemia (measured by plasma HbA1c) and progression of PAD among the diabetic population; and (2) a strong association between progression of the disease and family history of diabetes and ischemic vascular disease. There was a high death rate (34.25%) among the diabetic group, which was greater than for the age- and sex-matched nondiabetic controls (13.2%) drawn from the same practice. This high mortality was significantly related (P < .001) to the presence of PAD identified during first-year assessment. Once PAD develops in association with diabetes the long-term prognosis is poor and carries a high mortality rate mainly because of cardiovascular and cerebrovascular diseases. Both progression and mortality were significantly related to poor diabetic control. The role of the primary care nurse in assessing such patients by using Doppler-assisted measurements is one that should be expanded with the massive increase in the number of diabetic patients in the coming years.

Rapid foot and calf compression increases walking distance in patients with intermittent claudication: results of a randomized study

OBJECTIVE

The aim of our pilot study was to determine the usefulness of rapid, high-pressure, intermittent pneumatic calf and foot compression (IPCFC) in patients with stable intermittent claudication, with reference to the end points of improvement in initial claudication distance (ICD) (distance at which patient feels pain or discomfort in the legs), and improvement in absolute claudication distance (ACD) (distance at which patient stops walking because the pain or discomfort becomes severe).

METHODS

Thirty male patients presenting with stable, intermittent claudication (ACD between 50 and 150 meters on treadmill testing at 3.8 km/h, 10 degrees gradient) were recruited into this pilot study from a single center. Fifteen patients were randomized to treatment with IPCFC (applied for 1 hour twice daily in the sitting position) and were also advised to have daily exercise, and 15 patients served as controls, who were advised exercise alone. All patients received aspirin and had resting and postexercise ankle/brachial index (ABI) measured at enrollment along with ICD and ACD on treadmill testing (3.8 km/h, 10 degrees gradient). The mean age, baseline ICD, and ACD of the treatment and control groups were 70.4 +/- 7 years and 70.7 +/- 9 years, 55.8 +/- 15 meters and 68.4 +/- 17 meters, and 86.7 +/- 19 meters and 103.9 +/- 27 meters, respectively. Both groups were equally matched for risk factors, including smoking, type II diabetes mellitus, and hypercholesterolemia. IPCFC was applied. The study protocol included follow-up visits at 1, 2, 3, 4, 6, and 12 months with the ABI, ICD and ACD being measured at every visit.

RESULTS

The percent change from baseline for ICD and ACD for each patient visit and the mean +/- standard deviation (SD), standard error (SE), and median were calculated for the control and treatment groups. The percent change from baseline measurements (mean +/- SD) for ICD and ACD in the control group at 4, 6, and 12 months were 2.2 +/- 18 and 2.3 +/- 18, 2.9 +/- 17 and 5.2 +/- 20, and 3.6 +/- 18 and 5.8 +/- 20, respectively. In contrast, the changes in ICD and ACD at 4, 6, and 12 months in the treatment group were 137.1 +/- 128 (P < .01) and 84.3 +/- 82 (P < .01), 140.6 +/- 127 (P < .01) and 96.4 +/- 106 (P = .01), and 150.8 +/- 124 (P <0.01) and 101.2 +/- 104 (P <0.01), respectively. Although the ABI showed a slight increase in the treatment group, these differences were not statistically significant.

CONCLUSIONS

The results of this pilot study show that IPCFC improves walking distance in patients with stable intermittent claudication. A significant increase in ICD and ACD was seen at 4 and 6 months of treatment, respectively, and the improvement was sustained at 1 year. The combination of IPCFC with other treatment such as risk-factor modification and daily exercise may prove useful in patients with peripheral arterial occlusive disease. It may be a useful first line of therapy in patients with disabling claudication who are unfit for major reconstructive surgery. Improved walking on long-term follow-up and experience from different centers may establish a role for this treatment modality in the future.

Is the Stresst'er a Reliable Stress Test to Detect Mild to Moderate Peripheral Arterial Disease?

BACKGROUND

A stress test is required in patients with a resting ankle brachial pressure index (ABPI) of >0.9 in whom peripheral arterial disease (PAD) is suspected.

OBJECTIVE

To see if the Stresst'er Ergometer could mimic a standard 1 min treadmill exercise test and successfully diagnose the presence of significant PAD.

METHODS

Legs with a resting ABPI >0.9, a positive exercise test and PAD confirmed on Duplex ultrasound, underwent various protocols on the Stresst'er Ergometer. The results were compared to control legs with no PAD (normal stress test).

RESULTS

By making various adjustments to the rate and duration of the exercise, the resistance provided by the Stresst'er to the exercise and the timing of the post exercise ABPI measurement it was possible to accurately diagnose significant PAD.

CONCLUSION

Using an appropriate protocol it is possible to use the Stresst'er Ergometer to assist in the diagnosis of significant PAD. Being a portable, space saving device, the Stresst'er offers the opportunity of diagnosis outside the vascular laboratory. This would facilitate medical therapy to at risk patients.

Does Supervised Exercise Offer Adjuvant Benefit Over Exercise Advice Alone for the Treatment of Intermittent Claudication? A Randomised Trial

OBJECTIVE

Exercise advice is the main treatment for symptom relief in the UK for patients with mild to moderate Intermittent Claudication (IC). Would a weekly exercise and motivation class for 6 months offer adjuvant benefit over written and verbal exercise advice alone?

PATIENTS AND METHODS

Fifty-nine patients attending a regional vascular centre for whom IC was the main factor affecting mobility were randomised to either exercise advice alone (n=30) or exercise advice with a once a week 45 min supervised exercise/motivation class (n=29). The mean age was 68 years. Baseline and 6-month assessment included a Quality of Life Questionnaire--the Short-Form-36, the Charing Cross Symptom Specific Claudication Questionnaire (CCCQ) and treadmill walking distance (3.5 km/h 12%).

RESULTS

At 6-month follow-up the supervised exercise group had improved their treadmill walking by 129% compared to 69% in the advice alone group (p=0.001). This significant improvement was maintained at the subsequent 9 and 12-month follow-up assessments. By the 9-month stage the advice only group CCCQ score had improved 16% from baseline, while the supervised exercise group had a significantly better 43% improvement in base line score (p<0.05). Self reported frequency of walks was higher in the exercise class group being significant for improvement in CCCQ score.

CONCLUSION

A weekly, supervised exercise and motivation class for a 6-month period provides a significant improvement in patients' symptoms, quality of life, and distance walked compared with advice alone and this improvement continues after attendance at class has ceased.

Diagnosing external iliac endofibrosis by postexercise ankle to arm index in cyclists

PURPOSE

The aim of this study was to determine a noninvasive method of evaluating external iliac endofibrosis in cyclists.

METHODS

Eighteen highly trained male cyclists were divided into two groups: a pathology group (PG; 3 professional and 4 elite) and a control group (CG; 6 professional and 5 elite). Mean age was 26 +/- 6.1 yr for the PG and 24 +/- 4.09 for the CG. We studied humeral and tibial posterior pressure by using Doppler ultrasound and the ankle to arm index (AAI) before and after an incremental exercise test, performed on bike-ergometer until exhaustion. A Wilcoxon test was used to compare pressures and AAI in the PG. A Mann-Whitney test was used to compare the PG with the CG. Fisher discriminant analysis was done to obtain a classification of the legs in ill or normal legs.

RESULTS

The minimal AAI achieved in the PG was 0.76 +/- 0.13 for the normal leg (NL) and 0.35 +/- 0.04 for the ill leg (IL). We found significant differences (P < 0.01) from the 1st to 4th minute after exercise between the NL and the IL in the PG, and from the 1st to 10th minute after exercise between the IL and CG. We found significant differences in leg pressures between NL and IL in PG from the 1st to 4th minute (P < 0.01), and from the 1st to the 10th minute after exercise between CG and IL in the PG. Through discriminant analysis, we obtained a classification of the legs as ill or normal by applying a mathematical function at each recovery time studied.

CONCLUSIONS

AAI and leg pressures response to maximal exercise is a valid and noninvasive method for the evaluation of external iliac endofibrosis.

A prospective comparison of pedal ergometry with conventional treadmill testing in the investigation of lower extremity pain

BACKGROUND

Investigation of lower extremity pain is compromised by comorbid disorders that may interfere with conventional testing.

AIMS

To compare pedal ergometry with conventional treadmill testing.

METHODS

A prospective study was performed where patients presenting with a diagnosis of intermittent claudication were assessed by both methods of testing.

RESULTS

Of 78 patients studied with both tests, no exercise-induced ankle pressure changes occurred in 26, two were unable to complete either test despite normal pressure measurements, while 24 had exercise-induced pressure drop detected by both tests. Of patients who completed pedal ergometry, 21 were unable to complete the treadmill test, 14 of whom had negative ergometry, while seven had a pressure drop detected by pedal ergometry. Three had pressure changes with pedal ergometry, but not with treadmill testing and two had pressure changes on the treadmill not reproduced by pedal ergometry.

CONCLUSIONS

Pedal ergometer is more sensitive than treadmill testing in detecting arterial insufficiency, as indicated by a 20% or greater fall in ankle pressure, and more suitable in a subgroup of patients unable to tolerate conventional treadmill testing.

Pressure measurements at rest and after heavy exercise to detect moderate arterial lesions in athletes

PURPOSE

This study defined how ankle arterial blood pressure measurements should be analyzed for the detection of moderate arterial disease (asymptomatic while walking). We used external iliac artery endofibrosis as a unique model of an isolated moderate arterial lesion, the role of which in exercise-related pain can be surgically proven.

METHODS

Patients who were ambulatory in our institutional referral center were studied. Brachial pressures, ankle pressures, and heart rate were measured simultaneously on all four limbs at rest and after maximal exercise in 108 healthy athletes and 78 patients (among 89 athletes referred for suspicion of endofibrosis) with confirmed or excluded external iliac endofibrosis. For these 78 patients, we calculated systolic ankle pressure change, ankle/brachial index, and deviation from the ankle/brachial index to heart rate regression line (DAHR) that was defined in the 108 healthy athletes.

RESULTS

In patients with endofibrosis, ankle/brachial index and ankle pressure were normal at rest. One minute after exercise, areas (mean +/- SE of area) under the receiver operating characteristics curve for the diagnosis of endofibrosis were 0.91 +/- 0.02, 0.91 +/- 0.03, 0.95 +/- 0.02, and 0.96 +/- 0.02 for ankle pressure, pressure change, ankle/brachial index, and DAHR, respectively. For all criteria, area decreased with time in the recovery period.

CONCLUSION

After heavy-load exercise, the ankle/brachial index at minute 1 should be used rather than the systolic ankle pressure value or ankle pressure change as a means of improving the efficacy of the detection of endofibrosis in athletes. A 0.66 value of the index at minute 1 after maximal exercise seems an optimal cutoff point for clinical use, providing a 90% sensitivity rate and 87% specificity rate in the diagnosis of moderate arterial lesions. At rest and after 1 minute of recovery, the ankle/brachial index to heart rate relationship should be considered to be an efficient tool for analyzing the results of pressures measurements and improving detection efficiency.

Do we need to reappraise our method of interpreting the ankle brachial pressure index?

This prospective study aimed to investigate if there is a relationship between ankle brachial pressure index (ABPI) and brachial systolic pressure when measured using Doppler ultrasound. Sixty-two limbs (36 patients) in which arterial disease and diabetes mellitus could be excluded using published blood pressure and flow criteria were included in the study. All measurements were made with a Scimed PVL 50 (Bristol UK) using a revised version of the Whiston method and a one-minute treadmill walk. Statistical analysis was carried out using Pearson's product moment correlation and the t test. A relationship was found between the ABPI and brachial systolic pressure, with statistical analysis indicating that the ABPI was highest in hypotensive patients and lowest in hypertensive patients (r = -0.385, p < 0.01). This may suggest that the current practice of assigning one particular ABPI value as normal (1.00) is not reliable and that the way in which the index is interpreted needs to be reappraised.

Intestinal permeability is increased in patients with intermittent claudication

PURPOSE

Intermittent claudication can be regarded as repeated ischemia reperfusion injury, which can induce a generalized increase in vascular permeability, including in intestine. The lactulose mannitol test (L/M test) was performed in patients with intermittent claudication to evaluate the change in intestinal permeability when they were forced to walk.

METHODS

The L/M test was performed in 11 patients with intermittent claudication and 11 control subjects without intermittent claudication. The test was performed at rest and after exercise. Patients walked on a treadmill until they stopped because of pain. The control subjects were forced to walk as far as 200 m on a treadmill. The L/M test was repeated in the patients after successful arterial reconstruction. Then the patients were instructed to walk the same distance at the same speed as they had before surgery.

RESULTS

In patients, the mean L/M ratio after exercise was significantly higher than the mean L/M ratio when they were at rest (0.068 +/- 0.053 vs 0.022 +/- 0.009, P <.05). In control subjects, however, no significant difference was observed between the mean L/M ratios after exercise and at rest. The mean L/M ratio after exercise, decreased from 0.068 +/- 0.053 to 0.018 +/- 0. 016 after successful arterial reconstruction (P <.05) in patients.

CONCLUSION

Intestinal permeability, determined by means of the L/M test, significantly increased in patients with intermittent claudication after exercise, and it diminished after arterial reconstruction. The L/M test is, consequently, a new noninvasive method to reflect ischemia in lower limbs during exercise.

Assessment of intermittent claudication: a comparison of questionnaire, visual analogue scale and subjective estimate information with post-exercise ankle-brachial pressure index

In order to assess two simple methods of evaluation of claudication, a standard questionnaire and visual analogue scale, a comparison was made between them and the post-exercise pressure index used as a gold standard. Fifty-eight consecutive stable claudicants were recruited to the study, 51/58 having arterial insufficiency according to post-exercise pressure measurements. Both methods appeared to correlate rather poorly with post-exercise pressures. Thus visual analogue scale cannot be used alone to assess walking tolerance but as it offers qualitative information it may be used to supplement pressure measurements in the assessment of incapacity caused by intermittent claudication.

Poor reproducibility of exercise test in assessment of claudication

To assess reproducibility of the exercise test in intermittent claudication, a prospective, comparative, randomized study was undertaken. Ten patients with stable intermittent claudication of ischaemic origin were exercised on a flat surface (0-Ex), with 12% steady inclination (12-Ex) and with progressively increasing inclination (p-Ex) in a random order during three different sessions. The ankle-brachial index (ABI) at rest and after exercise (rABI, exABI), initial and maximum walking distance (IWD, MWD) and metabolic equivalent (MET) were obtained as the main outcome measures. The results were analysed using intraindividual coefficients of variation (CVs) and standard deviations (SDs). The ABI values of the worst extremity were used in evaluation of results. Reproducibility of the exercise ABI appeared to be good, especially during progressively increasing exercise, the mean CV being 9 +/- 5%. The best mean CV was observed during p-Ex (16% +/- 14%) for maximum walking distance. The mean CV for initial walking distances ranged from 30% to 54%. Treadmill exercise testing to measure walking distances is highly inaccurate and the value of exercise on the flat treadmill should be questioned. Graded exercise appeared to be the most reproducible in this respect. The ABI after exercise, however, was a reliable single parameter when assessing arterial insufficiency causing decreased walking capacity.

The Stresst'er ergometer as an alternative to treadmill testing in patients with claudication

OBJECTIVES

To compare a new pedal ergometer (the Stresst'er) with conventional treadmill examination in patients with leg pain on exercise.

DESIGN

Patients presenting with claudication were assessed by standard treadmill test and by the new device in two District General Hospitals.

METHODS

Ninety-four subjects were studied. Symptoms induced by both types of exercise were compared. Distance walked on the treadmill was compared to the number of pumps using the Stresst'er. The percentage change in ankle systolic pressure produced by the two tests was compared.

RESULTS

Subjective symptoms induced by the tests were similar. Distance walked did correlate with pumps on the ergometer, as did change in systolic pressure. Analysis of a subgroup of 41 cases with receiver operator curve (ROC) tests showed that the new device is sensitive and specific.

CONCLUSION

This new device is comparable with treadmill testing, but being easier to use, may have a place in the vascular clinic.

High prevalence of hyperhomocysteinemia and asymptomatic vascular disease in siblings of young patients with vascular disease and hyperhomocysteinemia

Hyperhomocysteinemia (HHC) is associated with an increased risk of atherosclerotic vascular disease and may be inherited. Fasting and postmethionine HHC are independent risk factors that overlap to a limited extent. To study the familial occurrence of HHC, we investigated the prevalence of HHC (both fasting and after methionine) among 450 siblings of 167 consecutive young patients with vascular disease and postmethionine HHC. Furthermore, all subjects with postmethionine HHC (n = 125) were invited for noninvasive vascular testing; 101 (80.8%) agreed. Of those with a normal postmethionine plasma level (n = 325), we randomly selected 73 subjects for further studies; 53 agreed (72.6%). Thus, a total of 154 siblings underwent ultrasonography of the carotid arteries, measurement of ankle-brachial pressure indices at rest and after a treadmill exercise test, and exercise electrocardiographic stress testing. We observed HHC after methionine, fasting, or both, in 27.8% (95% CI, 23.7 to 31.9), 11.1% (CI, 8.2 to 14.0) and 8.7% (CI, 6.1 to 11.3) of the siblings. Abnormal peripheral, coronary, or carotid artery tests were observed in 35.7% (CI, 28.1 to 43.3), 7.1% (CI, 3.0 to 11.2), and 7.1% (CI, 3.0 to 11.2). Univariate and multivariate analyses revealed weak evidence of a relationship with homocysteine levels. In conclusion, we found a high prevalence of HHC and asymptomatic vascular disease in siblings of young patients with vascular (mainly peripheral arterial) disease and HHC. Our data raise the possibility that homocysteine does not play a major role in the early, asymptomatic phases of vascular disease, at least among siblings of young patients with vascular disease.

A comparative study of treadmill tests and heel raising exercise for peripheral arterial disease

OBJECTIVES

This two part study validated a 1 min treadmill exercise test and compared this with simple heel raising exercise.

METHODS

In an initial study of 24 claudicants (aged 43-79, median 63 years), ankle pressures were measured immediately after repeated treadmill exercises: for 1 min, until onset of claudication, and until maximum tolerated walking distance. Absolute value, fall and percent change in pressures were calculated. The results of this part of the study were then used as a "gold standard" for comparison with 30 s of heel raising and treadmill exercise. This second stage was performed on 21 symptomatic limbs (14 claudicants aged 42-73, median 69 years).

RESULTS

Variability was least for pressures expressed as percent change after 1 min of exercise. The paired t-test revealed a significant correlation between the two methods of exercise (p < 0.05).

CONCLUSION

Heel raising produced changes in ankle pressure which correlated well with those induced by treadmill exercise. We recommend the use of simple heel raising when a stress test is required to diagnose lower limb arterial insufficiency in the outpatient clinic.

Ankle to arm index following maximal exercise in normal subjects and athletes

Recent reports have suggested that minor arterial lesions can be responsible for claudication in athletes occurring only during maximal exercise. Ankle to arm index measurements (AAI) prove the arterial origin of this claudication, but little is known about the normal response of AAI to maximal exercise. Therefore, we studied the response of AAI to maximal exercise in trained and untrained normal subjects. AAI and heart rate (HR) were recorded at rest and following maximal exercise on a cycle ergometer in 15 untrained (VO2 = 41.5 +/- 4.0 ml.kg-1.min-1) and 15 trained (VO2 = 58.4 +/- 2.8 ml.kg-1.min-1) volunteers. All subjects were without known peripheral arterial disease. At rest, AAI was 1.08 +/- 0.08 in untrained subjects and 1.15 +/- 0.05 in trained subjects (P < 0.05). HR was 73.9 +/- 11.0 in untrained subjects and 57.1 +/- 8.3 in trained subjects (P < 0.05). Following exercise, AAI decreased during the first minutes of recovery in all subjects, with a significant difference between untrained and trained subjects. Although untrained subjects sustained a lower workload than trained subjects, at 1 min following exercise AAI was 0.70 +/- 0.06 in untrained versus 0.8 +/- 0.08 in trained subjects (P < 0.05). No difference in AAI to HR relationships was noted between untrained and trained subjects. In conclusion, we suggest that AAI should be interpreted with regard to HR at the end of maximal exercise and we project normal results for the AAI to HR relationships following maximal exercise.

Comparison of lower limb arterial assessments using color-duplex ultrasound and ankle/brachial pressure index measurements

The strength of agreement between two noninvasive methods of assessing lower limb arterial disease and their relationship to patient symptoms following exercise have been investigated. Color-duplex ultrasound (CDU) and ankle/brachial pressure index (ABPI) (before and afer exercise) measurements were obtained from 200 consecutive patients referred to a vascular investigations laboratory. From these patients, 290 limbs were available for study, comprising limbs without previous vascular surgery, from patients without diabetes and who could attempt a walking exercise test. The overall level of agreement between CDU and resting ABPI measurements was 83% (Kappa 0.66). The ABPI technique identified the more serious disease; a resting ABPI of less than 0.6 gave 100% agreement with CDU. With higher resting ABPIs the level of agreement became poorer: 83% (0.6 < or = ABPI <0.9) and 76% (normal ABPI > or = 0.9). The addition of postexercise ABPI measurements in determining significant arterial disease increased the strength of relationship between the two techniques by only 2% (85%, Kappa 0.69). The exercise test was generally limited by the most symptomatic limb in each patient, and the agreement between CDU and postexercise ABPI measurements in these limbs was higher at 93% (Kappa 0.81). In comparison, agreement for the least symptomatic group of limbs was found to be poor (69%, Kappa 0.37). Compared with symptoms after exercise, overall agreements with CDU and ABPI were both 67% (Kappa 0.27). The agreement was better (91%) when the resting ABPI was less than 0.6. The ABPI is biased toward the detection of more severe disease and is more consistent with CDU when the most symptomatic limbs are compared. The relationship between either test and symptoms after exercise is strong only for limbs with major disease.

Ankle to arm index response to exercise and heat stress in healthy subjects

Ankle to arm index (AAI) defined as the ratio of ankle systolic blood pressure (ASBP), to brachial systolic blood pressure is largely used in the study of lower extremity arterial disease (LEAD). To study the hypothesis of the shunt of blood away from the skin as the explanation of AAI decrease in exercise, we studied the AAI and ASBP responses to an increase in cardiac output originating from an increase either in muscle blood flow (exercise) or in cutaneous blood flow (thermal stress). Brachial systolic pressure, ankle systolic pressure and heart rate (HR) were measured in 9 healthy subjects at rest, during heart thermal stress and following maximal exercise on a cycle ergometer. Compared to resting values, AAI decreased in all subjects from 1.05 +/- 0.07 to 0.75 +/- 0.07 (P < 0.05) 1 min following exercise and from 1.08 +/- 0.07 to 0.94 +/- 0.05 (P < 0.05) during heat stress. On the other hand, HR increased from 72.8 +/- 12.2 to 112.4 +/- 19.6 (P < 0.05) min following exercise and from 75.5 +/- 13.6 to 96.8 +/- 15.3 (P < 0.05) during heat stress. Since a comparable relation exists between AAI and HR in thermal stress and exercise, we suggest that the decrease in AAI in normal subjects following exercise is due to turbulences at high flow levels, rather than the shunting of blood to active muscles in exercise.

Antioxidant consumption during exercise in intermittent claudication

Twenty male claudicant patients and nine age-matched controls were exercised on a treadmill. Blood and urine samples were taken before and after exercise. Total antioxidant concentration was measured using an enhanced chemiluminescent assay and microalbuminuria determined by radioimmunoassay. Claudicants had increased microalbuminuria after exercise. Mean (s.e.m.) antioxidant concentrations were similar for patients and controls at rest: 479(28) and 438(23) mumol/l respectively. Claudicants showed a significant decrease in antioxidant concentration 1 min after exercise to 428(27) mumol/l; this returned to 470(30) mumol/l by 10 min. A correlation was found between the decrease in antioxidant concentration and the increase in microalbuminuria (rs = -0.496, P < 0.05). This study supports the concept of ischaemia-reperfusion injury in claudicant patients and has implications for treatment.

Postocclusive hyperaemic duplex scan: a new method of aortoiliac assessment

Aortoiliac duplex scanning, while accurate, is time-consuming and technically demanding. This study aimed to develop a fast, non-invasive screening test for aortoiliac disease. Colour duplex scanning was used to record common femoral Doppler ultrasonographic waveforms following 3 min of arterial occlusion using a thigh cuff in 25 patients with normal aortoiliac segments and 25 patients with significant aortoiliac disease. The latter patients had a prolonged period of postocclusive hyperaemic flow compared with the former. End diastolic velocity, 70 s after cuff release, was a significant discriminant between the two groups (sensitivity of 88 per cent, accuracy of 92 per cent). The postocclusive hyperaemic duplex (PHD) test performed well when used prospectively in a further 50 limbs (sensitivity of 86 per cent, accuracy of 84 per cent). The test was more sensitive than femoral pulse palpation and compared favourably with arteriography. The PHD test provides a simple, noninvasive assessment for aortoiliac disease that can be performed on the initial outpatient clinic visit.

Prospective assessment of an artificial neural network for the detection of peripheral vascular disease from lower limb pulse waveforms

The diagnostic performance of an artificial neural network pulse classification system for the detection of peripheral vascular disease was investigated prospectively. Lower limb photoelectric plethysmographic pulses, and Doppler ankle/brachial pressure index (ABPI) measurements (pre- and post-exercise) were obtained from 200 patients referred to a vascular investigation laboratory. A single toe pulse was processed and used as input data to a neural network which had been trained previously with a set of pulses from 100 legs. The neural network outputs represented the diagnostic arterial disease classifications defined by the ABPI. From the 200 patients entered prospectively, 266 legs were available for neural network assessment. A network sensitivity of 92% and specificity of 63% were achieved with a diagnostic accuracy of 80%. By using a higher confidence for the classification decision a small, but insignificant overall improvement was obtained. When a borderline classification was introduced 100% sensitivity and 100% negative predictive value were obtained, though 31% of legs were unclassifiable. Nevertheless, the very high sensitivity and negative predictive value could make this quick and simple technique the one of choice for the first stage in screening large numbers of subjects.

Significant association between low-molecular-weight apolipoprotein(a) isoforms and intermittent claudication

The role of lipoprotein(a) (Lp[a]) and apolipoprotein(a) (apo[a]) isoforms in symptomatic peripheral atherosclerosis was studied in 100 randomly selected middle-aged (45-69 years) men with intermittent claudication (IC) and 100 randomly selected healthy control (C) subjects. IC and C subjects were matched pairwise for sex, age, and smoking habits. Plasma Lp(a) concentrations were significantly higher in IC subjects, with a median value of 20.12 mg/dl, compared with 11.11 mg/dl in C subjects (p less than 0.0009). The elevated Lp(a) concentration was to a great extent due to a significant difference in the frequency distribution of apo(a) isoforms between IC and C subjects (p less than 0.029). Low-molecular-weight apo(a) isoforms were more prevalent in IC than C subjects. Also, IC subjects with apo(a) S2 and S3 phenotypes had higher Lp(a) concentrations than control subjects with the same phenotypes: S2:60.70 mg/dl (IC) and 48.69 mg/dl (C), p less than 0.038; and S3: 30.18 mg/dl (IC) and 12.01 mg/dl (C), p less than 0.042, so other still-unknown factors, genetic or nongenetic, may be important. Stepwise logistic regression analysis demonstrated that Lp(a) concentration contributed significantly (p less than 0.0002) to IC, independent of age, smoking, hypertension, diabetes mellitus, plasma total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, apo B, and plasma total triglycerides. Apo(a) isoforms grouped according to molecular weight were also independent of the above risk factors associated (p = 0.016) with the occurrence of IC because of their low-molecular-weight but were not independent of Lp(a) concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Hyperhomocyst(e)inaemia: an independent risk factor for intermittent claudication

The aim of this study was to test the question of hyperhomocyst(e)inaemia as a risk factor for intermittent claudication (IC) independent of other important risk factors for peripheral atherosclerotic disease, such as smoking, hypertension, diabetes mellitus, hypercholesterolaemia, hypertriglyceridaemia, low levels of high-density-lipoprotein (HLD) cholesterol and age. The study population was recruited from an epidemiological study in Linköping County, Sweden, where all middle-aged men (n = 15,253, 45-69 years of age) were screened for IC. Seventy-eight subjects with verified IC and 98 healthy sex- and age-matched controls were randomly selected. Plasma levels of homocyst(e)ine (including the sum of free and bound forms of homocysteine and their disulphide oxidation products, homocystine, and homocysteine-cysteine mixed disulphide) were significantly higher (16.74 +/- 5.45 mumol l-1, mean value +/- SD, P = 0.0002) in IC subjects than in controls (13.80 +/- 3.21 mumol l-1), with 23% of the claudicants above the 95th percentile for controls. Stepwise logistic regression analysis revealed that the difference in plasma homocyst(e)ine was independent of the other above-mentioned risk factors. Moreover, the elevation of plasma homocyst(e)ine in claudicants was mainly confined to subjects with serum folate levels of less than or equal to 11.0 nmol l-1. The results suggest that folic acid supplementation should be tried in IC subjects with hyperhomocyst(e)inaemia.

Effect of weight on claudication distance

Conservative measures to improve claudication distance include advice on smoking, exercise, diet and weight reduction. Although the effects of smoking, exercise and diet are established, the effect of weight is less clear. The aim of this study was to investigate the effect of carrying extra weight on the maximum walking distance in stable claudicants. Twenty stable claudicants were exercised on a treadmill (3.5 km/h, 0 degrees slope) carrying 0, 2.5, 5, 7.5 and 10 kg weights in randomized sequence. Maximum claudication distance and ankle: brachial pressure indices were recorded. Patients were categorized into mild or severe claudicants depending on their ability to walk 200 m. A response index (RI) was calculated as the reduction in claudication distance per kilogram load; RI = [CD0-CD10]/10 m/kg, where CD0 and CD10 represent claudication distance with 0 and 10 kg weights, respectively. Claudication distance was significantly reduced in subjects carrying 5 kg or more (P less than 0.01). A linear relationship was demonstrated between the mean claudication distance and the load carried (r = 0.98, P less than 0.01) with a mean response index of 10.2 m/kg. The mean(s.e.m.) RI in mild claudicants (25.9(9.5) m/kg) was greater than the value observed in the severe claudicants (3.3(0.8) m/kg; P less than 0.01, Mann-Whitney U test). This study demonstrates that weight adversely affects claudication distance and suggests that weight reduction may deserve greater emphasis in the management of some patients with intermittent claudication.