Resting Ankle Brachial Index Research Articles

Discordance of peripheral artery disease diagnosis using exercise transcutaneous oxygen pressure measurement and post-exercise ankle-brachial index

In patients with exertional limb symptoms and normal ankle-brachial index (ABI) at rest, exercise testing can be used to diagnose lower extremity arterial disease (LEAD). Post-exercise ABI decrease or Exercise transcutaneous oxygen pressure measurement (Exercise-TcPO2) can be used to diagnose LEAD. Objectives were (i) to assess the agreement between both methods (ii) to define the variables associated with the discordance, and (iii) to present results of healthy subjects. In this prospective cross-sectional study, patients with exertional limb symptoms and normal rest ABI were consecutively included. ABI was measured at rest and after standardized exercise protocol as well as Exercise-TcPO2. A kappa coefficient with a 95% confidence interval was used to assess the agreement between the two methods. Logistic regression analysis was performed to outline variables potentially responsible for discordance. Ninety-six patients were included. The agreement between the tests was weak with a k value of 0.23 [0.04–0.41]. Logistic regression analysis found that a medical history of lower extremity arterial stenting (odds ratio 5.85[1.68–20.44]) and age (odds ratio 1.06[1.01–1.11]) were the main cause of discordance. This study suggests that post-exercise ABI and Exercise-TcPO2 cannot be used interchangeably for the diagnosis of LEAD in patients with exertional symptoms and normal rest ABI.

Vacuum Therapy for Intermittent Claudication: A Randomized Controlled Trial

Introduction - Early 2015, intermittent vacuum therapy (IVT) was intensively promoted in the Netherlands as a minimally invasive treatment for intermittent claudication (IC). IVT implies that a patient is placed in a tubular device and undergoes periods of negative pressure applied to the lower body, assumed to stimulate leg circulation. A literature search revealed no evidence to substantiate claims that were made by the IVT company. Aim of this multicenter randomized controlled trial was to determine a potentially additional effect of IVT on walking distance and health-related quality of life in patients with IC. Methods - At three vascular surgery outpatient clinics, patients with symptomatic IC and a <0.90 rest ankle-brachial index (ABI) or a >0.15 ABI drop after exercise were randomized to two treatment arms. The experimental group (“IVT”) received supervised exercise therapy (SET) and IVT with a negative pressure of -50 mBar, whereas the control group (“Sham”) received SET and IVT with a negative pressure of -5 mBar. IVT was provided during twelve 30 minute sessions over a six weeks period. Patients and SET-providing physiotherapists were blinded for the given treatment. Primary outcome measure was the maximal walking distance (MWD) as measured by a standardized treadmill test. Secondary outcome measures were functional walking distance (FWD) and disease-specific quality of life (VascuQol questionnaire). Results - Seventy-eight patients were randomized (IVT, n=39; Sham, n=39; male 63%; mean age 68 ± 9 years). There were no baseline differences regarding walking distances and quality of life. MWD and FWD increased in both groups after six and 12 weeks (P<0.001). The median increase in MWD after 12 weeks was +220 m (100-430) in the IVT group versus +335 m (220-705) in the Sham group (P=0.055). The increase in FWD was +210 m (90-370) in the IVT group versus +230 m (145-391) in the Sham group (P=0.201). After 12 weeks, no significant differences in absolute walking distances between groups were found. Disease-specific quality of life also increased in both groups although significant differences between groups were again absent. Conclusion - Intermittent vacuum therapy does not confer an additional beneficial effect on walking distance and health-related quality of life in patients with IC.

The Ability of the Toe-Brachial Index to Predict the Outcome of Treadmill Exercise Testing in Patients with a Normal Resting Ankle-Brachial Index

Peripheral arterial disease (PAD) in the presence of a normal ankle-brachial index (ABI) can be diagnosed noninvasively by measuring a postexercise ABI or by measuring the toe-brachial index (TBI). This was a prospective comparative study. Over a period of 30months, a total of 415 patients who were referred with the suspicion of vascular claudication and resting values of 0.91≤ABI<1.40 were further evaluated for the resting TBI and postexercise ABI by treadmill testing. A total of 325 (39%) of the 830 investigated limbs had a low TBI (≤0.70), and 505 (61%) had a normal TBI. Of the limbs with a low TBI, 160 (49%) had PAD according to a postexercise ABI versus 165 (33%) of the limbs with normal TBI. The overall agreement in PAD classification between the two methods was 500/830 (60%) with a Cohen's kappa=0.166 (95% CI: 0.096-0.232). The data showed an inverse correlation between the magnitude of the TBI decrease, as well as the resting ABI, and the probability of an abnormal postexercise ABI. On average, limbs with a low TBI had a lower resting ABI than patients with a normal TBI (1.07±0.09 vs. 1.13±0.10, P<0.001). The groups with a low TBI had a significantly higher ratio of abnormal test results than patients with a normal TBI, in limbs with ABI (0.96-1.00) and ABI >1.10 (P≤0.022 for both), but there were no statistically significant differences found in other ABI intervals (P>0.200 for all). The magnitude of the TBI reduction correlates with an increased probability of an abnormal postexercise ABI. However, this is due in part to limbs with a low TBI having a lower resting ABI on average than limbs with a normal TBI, which also correlates with the probability of an abnormal exercise test result. This study shows that the TBI and the postexercise ABI are not interchangeable for establishing a PAD diagnosis.

Safety and Efficacy of Placenta-Derived Mesenchymal Stem Cell Treatment for Diabetic Patients with Critical Limb Ischemia: A Pilot Study.

Diabetic foot has become the main cause of non-traumatic amputation. Stem cell therapy, especially mesenchymal stem cells (MSCs), holds a great promise as a therapy for diabetic foot with ischemia limb arterial disease. The aim of this pilot study is to evaluate the safety and efficacy of placenta-derived MSCs (P-MSCs) treatment for diabetic patients with critical limb ischemia (CLI). Four eligible diabetic patients with CLI were consecutively enrolled in this pilot study. On the base of the standard-of-care treatment, these patients accepted P-MSCs treatment by intramuscular injection for successive 3 times at an interval of 4 weeks, and the safety and efficacy of placenta-derived MSCs (P-MSCs) treatment were evaluated. There were no serious adverse events during the period of P-MSCs injection and the 24-weeks follow-up period. The clinical ischemic features of patients were improved 24 weeks after P-MSCs treatment. The scores of resting pain and limb coldness significantly decreased, and pain-free walking distance significantly increased from baseline to 24 weeks after P-MSCs therapy. The resting ankle brachial index increased, but no statistically significant difference was found. The findings of magnetic resonance angiography showed the increase of collateral vessel formation in one patient, but there were no significant changes observed in the other patients. The data in this pilot study indicated that multiple intramuscular P-MSCs injections may be a safe and effective alternative therapy for diabetic patients with CLI, and larger, placebo-controlled, perspective studies are needed to prove these results.

How to become proficient in performance of the resting ankle-brachial index: Results of the first randomized controlled trial.

The resting ankle-brachial index (ABI) is a first-line test to diagnose peripheral artery disease (PAD). No randomized controlled trial (RCT) has yet been conducted to determine the best teaching method to become proficient in the ABI procedure. We conducted a monocentric RCT to determine whether didactic learning alone or didactic learning combined with experiential learning improved proficiency in the ABI procedure. Medical students ( n = 30) received didactic learning, including (i) a presentation of the ABI guidelines and (ii) a video demonstration. Each student was then randomized into two groups ('no experiential learning group' and 'experiential learning group'). An initial evaluation was performed after the didactic learning and a final evaluation at the end of the intervention. A student was considered to be proficient when he or she performed a correct ABI procedure on a healthy individual and a patient. The correct procedure corresponds to (i) following guidelines and (ii) a difference in ABI measurement between a vascular specialist and a student of ≤ 0.15. No student was proficient at the initial evaluation. At the final evaluation, in the didactic learning group, the number of proficient students was not improved compared with the initial evaluation (0/10 vs 1/10). In the experiential learning group, the number of proficient students was significantly improved (0/20 vs 11/20; p < 0.05). At the final evaluation, there was a significant difference between the number of proficient students depending on their learning group. In conclusion, didactic learning alone is insufficient to gain proficiency in the ABI procedure. Combining didactic learning with experiential learning significantly improved the students' proficiency.

Comparative Efficacy of Endovascular Revascularization Versus Supervised Exercise Training in Patients With Intermittent Claudication: Meta-Analysis of Randomized Controlled Trials

ObjectivesThe authors performed a meta-analysis of randomized controlled trials to compare the efficacy of initial endovascular treatment with or without supervised exercise training (SET) versus SET alone in patients with intermittent claudication. BackgroundCurrent guidelines recommend SET as the initial treatment modality for patients with intermittent claudication, in addition to optimal medical therapy. The role of endovascular therapy as primary treatment for claudication has been controversial. MethodsThe primary outcome was treadmill-measured maximal walk distance at the end of follow-up. Secondary outcomes included resting ankle brachial index (ABI) and treadmill-measured ischemic claudication distance on follow-up. Risk of revascularization or amputations was also compared. Pooled estimates of the difference in outcomes between endovascular therapy with or without SET and SET-only groups were calculated using fixed and random effects models. ResultsA total of 987 patients from 7 trials were included. In pooled analysis, compared with SET only (reference group), patients that underwent combined endovascular therapy and SET had significantly higher maximum walk distance (standardized mean difference 0.79 [95% confidence interval (CI): 0.18 to 1.39]; weighted mean difference 98.9 [95% CI: 31.4 to 166.4 feet], and lower risk of revascularization or amputation (odds ratio 0.19 [95% CI: (0.09 to 0.40]; p < 0.0001, number needed to treat = 8) over a median follow-up of 12.4 months. By contrast, revascularization was not associated with significant improvement in exercise capacity or risk of future revascularization or amputation, compared with SET alone. Follow-up ABI was significantly higher among patients that underwent endovascular therapy with or without SET as compared with SET alone. ConclusionsCompared with initial SET only, endovascular therapy in combination with SET is associated with significant improvement in total walking distance, ABI, and risk of future revascularization or amputation. By contrast, endovascular therapy-only was not associated with any improvement in functional capacity or clinical outcomes over an intermediate duration of follow-up.

Lumbar sympathectomy techniques for critical lower limb ischaemia due to non-reconstructable peripheral arterial disease.

Critical lower limb ischaemia (CLI) is a manifestation of peripheral arterial disease (PAD) that is seen in patients with typical chronic ischaemic rest pain or patients with ischaemic skin lesions - ulcers or gangrene - for longer than 2 weeks. Critical lower limb ischaemia is the most severe form of PAD, and interventions to improve arterial perfusion become necessary. Although surgical bypass has been the gold standard for revascularisation, the extent or the site of disease may be such that the artery cannot be reconstructed or bypassed. These patients require other modalities of treatment, for example, vasodilatation by drugs or lumbar sympathectomy to relieve pain at rest and to avoid amputations. A systematic review of randomised controlled trials is required to evaluate the effects of lumbar sympathectomy in treating patients with CLI due to non-reconstructable PAD. The objective of this review is to assess the effects of lumbar sympathectomy by open, laparoscopic and percutaneous methods compared with no treatment or compared with any other method of lumbar sympathectomy in patients with CLI due to non-reconstructable PAD. The Cochrane Vascular Information Specialist (CIS) searched the Specialised Register (January 2016) and the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 12). In addition, the CIS searched clinical trials databases for details of ongoing and unpublished studies. Randomised controlled trials (RCTs) comparing any of the treatment modalities of lumbar sympathectomy, such as open, laparoscopic and chemical percutaneous methods, with no treatment or with any other method of lumbar sympathectomy for CLI due to non-reconstructable PAD were eligible. To decrease the bias of including participants that may be incorrectly diagnosed with CLI, review authors defined CLI as persistently recurring ischaemic rest pain requiring regular analgesia for more than two weeks, or ulceration or gangrene of the foot or toes, attributable to objectively proven arterial occlusive disease by measurement of ankle pressure of < 50 mmHg or toe pressure < 30 mmHg. We defined non-reconstructable PAD as a resting ankle brachial index (ABI) < 0.9 when no reasonable open surgical or endovascular revascularisation treatment option is available, as determined by individual trial vascular specialists. Two review authors independently assessed studies identified for potential inclusion in the review. We planned to conduct data collection and analysis in accordance with the Cochrane Handbook for Systematic Review of Interventions. We identified no studies that met the predefined inclusion criteria. To decrease the bias of including participants who may be incorrectly diagnosed with CLI, we based our inclusion criteria on objective tests, as described above. The randomised trials identified by the literature search were performed before such objective criteria for selection were applied and therefore were not eligible for inclusion in the review. We identified no RCTs assessing effects of lumbar sympathectomy by open, laparoscopic and percutaneous methods compared with no treatment or compared with any other method of lumbar sympathectomy in patients with CLI due to non-reconstructable PAD. High-quality studies are needed.

Abstract 19720: Jay D. Coffman Early Career Investigator Award: Comparative Efficacy of Initial Endovascular Revascularization vs. Supervised Exercise Training in Patients With Intermittent Claudication: A Meta-analysis of Randomized Controlled Trials

Introduction: Current guidelines recommend supervised exercise training (SET) as the initial treatment modality for patients with intermittent claudication (IC), in addition to optimal medical therapy. The role of endovascular revascularization (ER) as a primary treatment option has been controversial. We performed a meta-analysis to compare the efficacy of initial ER vs. initial SET in patients with IC using data from randomized controlled trials. Methods: The primary outcome was treadmill-measured maximum walking distance (MWD) at the end of follow-up. Secondary outcomes included resting ankle brachial index (ABI) and treadmill-measured ischemic claudication distance (ICD) on follow-up. Risk of adverse limb events (revascularization, amputations) was also compared between the two groups. Random effects models were used for all analyses. Results: We included 1,145 patients from nine trials with a mean follow up duration of 13.7 months (42% aortoiliac lesions; 35% stent use; mean baseline ABI 0.64 vs. 0.67 for ER vs. SET). Follow-up MWD was not significantly different between patients undergoing ER vs. SET [Weighted mean difference (WMD) (95% CI): 19.1 m (-79.6 to 117.8 m); publication bias p=0.86]. Metaregression did not identify significant differences based on stent use or presence of aortoiliac disease. ICD was also similar between the two groups [WMD (95% CI): 36.1 m (-99.4 to 171.5 m)]. In contrast, patients undergoing ER had higher resting ABI on follow-up [WMD (95% CI): 0.14 (0.11 to 0.17), p&lt;0.0001]. Adverse limb event rates were similar [5.4% vs. 8.2%, p=0.21]. Conclusion: Compared with initial SET, initial ER significantly improves resting ABI values. Although longer walking distance and lower rates of adverse limb events also appeared favorable for ER, these differences were not statistically significant in these intermediate term studies. Longer-term studies and those incorporating contemporary revascularization techniques are necessary.

Screening for Peripheral Artery Disease and Cardiovascular Disease Risk Assessment With the Ankle–Brachial Index in Adults: U.S. Preventive Services Task Force Recommendation Statement

Update of the 2005 U.S. Preventive Services Task Force (USPSTF) recommendation on screening for peripheral artery disease (PAD). The USPSTF reviewed the evidence on the use of resting ankle-brachial index (ABI) as a screening test for PAD or as a risk predictor for cardiovascular disease (CVD). The review focused on resting ABI as the sole screening method; the diagnostic performance of ABI testing in primary care populations, unselected populations, and asymptomatic populations; the predictive value of ABI testing for major CVD outcomes in primary care or unselected populations; and the effect of treatment on general CVD and PAD-specific morbidity in patients with asymptomatic or minimally symptomatic PAD. This recommendation applies to asymptomatic adults who do not have a known diagnosis of PAD, CVD, severe chronic kidney disease, or diabetes. The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for PAD and CVD risk assessment with the ABI in adults. (I statement).

The Prevalence of Peripheral Arterial Disease in HIV Patients

Background: The actual prevalence of Peripheral Arterial Disease (PAD) in Human Immunodeficiency Virus (HIV) infected patients is still unknown. Aim: The aim of our study was to assess the prevalence of PAD using Ankle Brachial Index (ABI) (both rest and exercise) measurement in HIV infected patients with head-to-head comparison with the sex-matched non-HIV controls. Methods: We randomly enrolled total of 214 patients (70 HIV patients and 144 non-HIV controls), from March 2009 to December 2009. The Edinburg Claudication Questionnaire and ABI were used as study tools. Normal ABI was defined as 0.9 to 1.3. Data was analyzed using the Fischer’s Exact Test. Various cardiovascular and infectious risk factors for PAD were also analyzed. Results: Claudication was reported using Edinburgh questionnaire in 28.5% HIV patients as compared to 12.5 % patients in non-HIV group (p value 0.0069). Abnormal ABI suggestive of PAD i.e. ABI 15% absolute drop on exercise was reported in 10% HIV patients as compared to 1.3% in non-HIV group (p value 0.006). Based on multivariate analysis, age, Caucasian race, hypertension, diabetes mellitus, hyperlipidemia, metabolic syndrome and low CD4 count were found to be independent predictors of PAD. Conclusions: The prevalence of PAD is higher in HIV patients as compared to sex-matched non-HIV controls. Hence, HIV patients should be routinely screened for PAD using rest and exercise ABI. Apart from correlation with cardiovascular risk factors, strong association between lower CD4 cell count and abnormal ABI exists. This warrants more aggressive approach in managing cardiovascular and infectious markers in HIV patients with abnormal ABI.

Percutaneous intervention in peripheral artery disease improves calf muscle phosphocreatine recovery kinetics: A pilot study

We hypothesized that percutaneous intervention in the affected lower extremity artery would improve calf muscle perfusion and cellular metabolism in patients with claudication and peripheral artery disease (PAD) as measured by magnetic resonance imaging (MRI) and spectroscopy (MRS). Ten patients with symptomatic PAD (mean ± SD: age 57 ± 9 years; ankle-brachial index (ABI) 0.62 ± 0.17; seven males) were studied 2 months before and 10 months after lower extremity percutaneous intervention. Calf muscle phosphocreatine recovery time constant (PCr) in the revascularized leg was measured by (31)P MRS immediately after symptom-limited exercise on a 1.5-T scanner. Calf muscle perfusion was measured using first-pass gadolinium-enhanced MRI at peak exercise. A 6-minute walk and treadmill test were performed. The PCr recovery time constant improved significantly following intervention (91 ± 33 s to 52 ± 34 s, p < 0.003). Rest ABI also improved (0.62 ± 0.17 to 0.93 ± 0.25, p < 0.003). There was no difference in MRI-measured tissue perfusion or exercise parameters, although the study was underpowered for these endpoints. In conclusion, in this pilot study, successful large vessel percutaneous intervention in patients with symptomatic claudication, results in improved ABI and calf muscle phosphocreatine recovery kinetics.

Exercise ankle brachial index adds important prognostic information on long-term out-come only in patients with a normal resting ankle brachial index

BackgroundThe clinical value of exercise ankle brachial index (ABI) is still unclear, especially in patients with normal resting ABI. Method2164 patients performed a single-stage treadmill exercise test to diagnose or evaluate PAD. The population was divided into two groups: a normal resting ABI (resting ABI≥0.90) and PAD (resting ABI<0.90). Patients with a normal resting ABI were divided into 4 exercise ABI groups: exercise ABI<0.90, 0.90–0.99, 1.00–1.09 and 1.10–1.29 (reference). ResultsMean follow-up was 5years. Exercise ABI added significant prognostic information on all cause long-term mortality only in patients with normal resting ABI (p-value 0.014, HR 0.99 95% CI (0.98–0.99)), not in patients with PAD. Fifty years or older (OR 2.93 95% CI (1.65–5.20)) and resting systolic blood pressure>140mmHg (OR 2.18 95% CI (1.35–3.55)) were associated with an abnormal exercise ABI in patients with a normal resting ABI. Mortality rate increased when the exercise ABI became worse (p trend 0.0001) with a 2.5-fold increase mortality risk in patients with a normal resting ABI but exercise ABI <0.90 (HR 2.56, 95% CI (1.11–5.91)). ConclusionIn patients with a normal resting ABI, treadmill exercise ABI added important prognostic information on long-term mortality. Based on our results we recommend that at least all patients suspected for PAD, with a resting ABI≥0.90, who are 50years or older and having hypertension should undergo treadmill exercise testing.

A decline in walking distance predicts long-term outcome in patients with known or suspected peripheral artery disease

To assess the predictive value of a decline in total walking distance and ankle brachial index (ABI) on all-cause mortality and cardiac death in patients with known or suspected peripheral artery disease. Two hundred and sixty-one patients, who performed single-stage treadmill walking test twice to evaluate their peripheral artery disease, were enrolled in an observational study. Patients who underwent surgery during follow-up were excluded. Delta total walking distance and delta resting and exercise ABI consisted of the difference between the first and the second test. All three variables were categorized into two groups: stable/improvement or a decline. The mean follow-up period was 6 years. At both 5 years and total follow-up, a decline in total walking distance was independent and highly associated with an increased mortality risk and cardiac death [hazard ratio: 2.31 (95% confidence interval 1.35-3.96); hazard ratio: 3.55 (95% confidence interval: 1.53-8.21), respectively]. A decline in resting or exercise ABI after adjustment for delta walking distance was not significantly associated with all-cause mortality or cardiac death. A decline in total walking distance in single-stage treadmill exercise tests is a strong prognostic predictor of all-cause mortality and cardiac death in the short term and long term.

Limb Stress-Rest Perfusion Imaging With Contrast Ultrasound for the Assessment of Peripheral Arterial Disease Severity

We hypothesized that stress-rest perfusion imaging of skeletal muscle in the lower extremity with contrast-enhanced ultrasound (CEU) could evaluate the severity of peripheral arterial disease (PAD). Perfusion imaging may provide valuable quantitative information on PAD, particularly in patients with diabetes in whom microvascular functional abnormalities are common. Study subjects included 26 control subjects and 39 patients with symptomatic PAD, 19 of whom had type 2 diabetes mellitus. A modified treadmill exercise test was performed to determine exercise time to development of claudication. Multilevel pulse-volume recordings and ankle-brachial index (ABI) at rest and post-exercise ABI were measured in both extremities. Microvascular blood flow in the gastrocnemius and soleus muscles was measured at rest and after 2 min of calibrated plantar-flexion exercise. During exercise, claudication did not occur in normal subjects and occurred earlier in PAD patients with diabetes than without (median time 1.2 min [95% confidence interval (CI) 0.6 to 2.5] vs. 3.0 min [95% CI 2.1 to 6.0], p < 0.01). Compared to control subjects, patients with PAD had lower skeletal muscle blood flow during plantar-flexion exercise and lower flow reserve on CEU. After adjusting for diabetes, the only diagnostic tests that predicted severity of disease by claudication threshold were CEU exercise blood flow and flow reserve (odds ratios 0.67 [95% CI 0.51 to 0.88; p = 0.003] and 0.64 [95% CI 0.46 to 0.89, p = 0.008], respectively). A quasi-likelihood information analysis incorporating all non-invasive diagnostic tests indicated that the best models for predicting severity of disease were the combination of diabetes and either exercise blood flow or flow-reserve on CEU. Perfusion imaging of limb skeletal during exercise and measurement of absolute flow reserve can provide valuable information on the severity PAD. This strategy may be useful for evaluating the total impact of disease in patients with complex disease or those with coexisting functional abnormalities of flow regulation.

Long-term Patency and Clinical Outcome of the Viabahn Stent-Graft for Femoropopliteal Artery Obstructions

To assess the long-term patency of the Viabahn stent-graft after placement for the treatment of occlusive disease of the femoropopliteal artery (FPA). Viabahn stent-grafts were placed into 87 limbs in 76 patients for the treatment of atherosclerotic occlusive disease of the FPA. Mean lesion length was 14.2 cm (range, 2.8-40 cm), with 80 of 87 lesions (92%) at least 7 cm in length. Patients were followed by duplex ultrasound (US), resting ankle brachial index (ABI) measurement, and clinical status at 6 months, 1 year, and yearly thereafter for a maximum of 8.5 years. A systolic velocity ratio greater than 2.0 on duplex US anywhere in the FPA was defined as a loss of primary vessel patency. Primary, primary assisted, and secondary vessel patency rates were 76%, 87%, and 93%, respectively, at 1 year and 55%, 67%, and 79%, respectively, at 4 years. Mean resting ABI improved from 0.70 before the procedure to 0.90 as of the most recent follow-up (P<.001). Mean Rutherford-Becker classification improved from 3.4 before the procedure to 0.68 as of the most recent follow-up (P<.001). Eighty-eight percent of limbs showed a maintained improvement in clinical status. Primary patency was independent of lesion length and type but dependent on device diameter (P=.001). The primary vessel patency rate in devices of at least 7 mm (n=21) was 82% at 4 years. No stent fractures were observed despite the use of multiple overlapping stent-grafts in 36.8% of limbs (n=32). This study demonstrates durable vessel patency to 4 years for long Transatlantic Inter-Society Consensus class C and D lesions treated with the Viabahn stent-graft. Results were independent of lesion length and type but dependent on device diameter. This study helps confirm the durability and clinical utility of this device in the treatment of FPA occlusive disease.

Supervised exercise therapy for intermittent claudication in a community-based setting is as effective as clinic-based

This cohort study was conducted to determine the effect on walking distances of supervised exercise therapy provided in a community-based setting. The study included all consecutive patients presenting at the vascular outpatient clinic with intermittent claudication, diagnosed by a resting ankle brachial index<0.9, who had no previous peripheral vascular intervention for peripheral arterial disease, no major amputation, and sufficient command of the Dutch language. The exclusion criterion was the inability to walk the baseline treadmill test for a minimum of 10 m. The intervention was a supervised exercise therapy in a community-based setting. A progressive treadmill test at baseline and at 1, 3, and 6 months of follow-up measured initial claudication distance and absolute claudication distance. Changes were calculated using the mean percentages of change. From January through October 2005, 93 consecutive patients with claudication were eligible. Overall, 37 patients discontinued the supervised exercise therapy program. Eleven stopped because of intercurrent diseases, whereas for 10, supervised exercise therapy did not lead to adequate improvement and they underwent a vascular intervention. Three patients quit the program, stating that they were satisfied with the regained walking distance and did not require further supervised exercise therapy. Ten patients were not motivated sufficiently to continue the program, and in three patients, a lack of adequate insurance coverage was the reason for dropping out. Data for 56 patients were used and showed a mean percentage increase in initial claudication distance of 187% after 3 months and 240% after 6 months. The mean percentage of the absolute claudication distance increased 142% after 3 months and 191% after 6 months. Supervised exercise therapy in a community-based setting is a promising approach to providing conservative treatment for patients with intermittent claudication.

Simvastatin Effects in Normo‐ and Hypercholesterolaemic Patients with Peripheral Arterial Occlusive Disease: A Pilot Study

Abstract: Improvement of endothelial function caused by statin treatment is not related to lowering of the cholesterol levels but results primarily from statin pleiotropic effects. Accordingly, we designed a pilot study in 10 normocholesterolaemic and 10 hypercholesterolaemic patients with peripheral arterial occlusive disease to investigate potential biological effects of statins in relation to their effects on endothelial function. The patients were treated with simvastatin 40 mg/daily for 3 months. Simvastatin led to significant reduction in total cholesterol and trigliceride levels in normocholesterolaemic and hypercholesterolaemic patients. Elongation of pain‐free and total walking distance was observed in both groups studied. Inconsiderable changes in rest ankle brachial index were seen. Flow‐mediated dilation increased in normocholesterolaemic group by 153% and in the hypercholesterolaemic group by 180% after 3 months of treatment. Euglobulin clot lysis time was shortened significantly in both groups each time after drug intake. Platelet aggregates ratio was increased in normocholesterolaemic patients by 8.9% and in hypercholesterolaemic patients by 17.6% each time after intake and remained significantly increased during the observation after 1 and 3 months. Simvastatin inhibited platelet aggregation induced by collagen and ADP in both study groups 3 hr after intake, but the platelets of hypercholesterolaemic patients were less sensitive to these aggregatory agents after 3 months of treatment. Simvastatin therapy caused clinical improvement in normocholesterolaemic and hypercholesterolaemic patients with peripheral occlusive disease. It is suggested that this effect is due to the restoration of endothelial function.

Primary stent-supported angioplasty for treatment of below-knee critical limb ischemia and severe claudication: Early and one-year outcomes

The objective of this study was an investigation of the safety and efficacy of primary below-knee stent-supported angioplasty (BKSSA) for restoring straight inline arterial flow in patients with critical limb ischemia (CLI) or lifestyle-limiting claudication (LLC). Surgical tibial bypass for CLI and severe LLC is associated with significant morbidity, mortality, and graft failure, whereas percutaneous angioplasty is suboptimal. Below-knee stent-supported angioplasty was attempted in 82 patients (92 limbs) with either CLI (68%) or severe LLC (32%). Patients received daily aspirin, thienopyridine, and glycoprotein IIb/IIIa agents during the procedure. One-month major adverse events (MAEs) were defined as death, myocardial infarction, major unplanned amputation, need for surgical revascularization, or major bleeding. Clinical success was defined as improved resting ankle brachial index by > or =0.10, relief of resting pain, healing of ulceration or amputation, and improvement of claudication. Mean age of patients was 74 +/- 17 years. In 86 limbs, straight inline flow was restored to at least one tibial vessel. Technical success was 94% for de novo lesions and there were no MAEs. Ankle brachial indexes increased for all groups (CLI = 0.32 +/- 0.13 to 0.9 +/- 0.14 and LLC = 0.65 +/- 0.09 to 0.95 +/- 0.12; p < or = 0.0001, pre vs. post). Relief of rest pain and healing of ulcerations and amputations were seen in 96% (47 of 49) of patients with CLI who underwent successful intervention. Below-knee stent-supported angioplasty for CLI and LLC improves ankle brachial indexes comparable to tibial bypass, heals amputations and ulcerations, relieves rest pain, and improves ambulation. Because BKSSA is associated with minimal MAE, it may hold promise as an alternative therapy for patients with CLI and LLC.

Intravascular Radiation Therapy after Balloon Angioplasty of Narrowed Femoropopliteal Arteries to Prevent Restenosis: Results of the PARIS Feasibility Clinical Trial

To conduct a feasibility study to assess the feasibility, safety, and outcome of endoluminal gamma radiation therapy after balloon angioplasty of superficial femoral artery (SFA) lesions. Forty patients with claudication were enrolled in the study and underwent percutaneous transluminal angioplasty (PTA) of SFA lesions with a mean lesion length of 9.8 cm +/- 3.0 and a mean reference vessel diameter of 5.2 mm +/- 3.1. After successful PTA, a segmented centering balloon catheter was positioned to cover the PTA site. The patients were then transported to the radiation oncology suite and treated with a microSelectron HDR afterloader with use of an Ir-192 source with a prescribed dose of 14 Gy, 2 mm into the vessel wall. Ankle-brachial index (ABI) and Rutherford score were evaluated at 1, 6, and 12 months after the procedure and angiographic follow-up was conducted at 6 months. Radiation was delivered successfully to 35 of 40 patients. There were no procedural complications. Exercise and rest ABI were higher at 1 year (0.72 +/- 0.26 and 0.89 +/- 0.18, respectively) compared to baseline (0.51 +/- 0.25 and 0.67 +/- 0.17, respectively). Maximum walking time on a treadmill increased from 3.41 min +/- 2.41 to 4.43 min +/- 2.49 at 30 days and was 4.04 min +/- 2.8 at 12 months. The angiographic binary restenosis rate at 6 months was 17.2% and the clinical restenosis rate at 12 months was 13.3%. There were no angiographic or clinical adverse events related to the radiation therapy. Intraarterial radiation after PTA of SFA lesions with use of high-dose rate gamma radiation is feasible and safe. The angiographic and clinical improvements are sustainable at 1 year and represent a potent antirestenotic therapy for the treatment of narrowed peripheral arteries.

The relationship between ankle brachial index, other atherosclerotic disease, diabetes, smoking and mortality in older men and women

The goal of this study is to investigate the relationship between peripheral arterial disease and mortality in a large patient population and assess the effects of other atherosclerotic diseases, diabetes and smoking on this relationship. All patients, 50 years or older and with no history of lower extremity surgery, evaluated for lower extremity arterial disease in a university hospital peripheral vascular laboratory over a 13-year period (1977–1989) were included in the study ( n = 1930). Arterial disease was assessed by measurement of the resting ankle brachial index (ABI) in these patients. The ABI was calculated by dividing the systolic pressure in the tibial arteries by the pressure in the brachial artery. Analyses of the data by use of multivariate statistical techniques and by stratification of the patient population by co-morbid condition indicate that ABI is a robust and independent predictor of all-cause mortality in both men (relative risk (RR) = 1.6,95% confidence interval (CI)1.3, 2.0) and women (RR = 1.9,95% CI 1.4, 2.4). The relative risks are essentially unchanged after exclusion of all patients with clinical history of cardiovascular disease or diabetes. Similarly, a low ABI is an important risk factor for mortality among patients with a history of stroke, angina or diabetes; men and women with a history of smoking and women who are non-smokers. Therefore, the measurement of ABI, a simple, objective, non-invasive technique which can be used in the physician's office, may be useful for early identification of patients at high risk for morbidity and mortality.