Antiplatelet agents for intermittent claudication

Effects of additional exercise therapy after a successful vascular intervention for people with symptomatic peripheral arterial disease

BACKGROUND

Peripheral arterial disease (PAD) is characterised by obstruction or narrowing of the large arteries of the lower limbs, usually caused by atheromatous plaques. Most people with PAD who experience intermittent leg pain (intermittent claudication) are typically treated with secondary prevention strategies, including medical management and exercise therapy. Lower limb revascularisation may be suitable for people with significant disability and those who do not show satisfactory improvement after conservative treatment. Some studies have suggested that lower limb revascularisation for PAD may not confer significantly more benefits than supervised exercise alone for improved physical function and quality of life. It is proposed that supervised exercise therapy as adjunctive treatment after successful lower limb revascularisation may confer additional benefits, surpassing the effects conferred by either treatment alone.

OBJECTIVES

To assess the effects of a supervised exercise programme versus standard care following successful lower limb revascularisation in people with PAD.

SEARCH METHODS

We searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, two other databases, and two trial registers, most recently on 14 March 2023.

SELECTION CRITERIA

We included randomised controlled trials which compared supervised exercise training following lower limb revascularisation with standard care following lower limb revascularisation in adults (18 years and older) with PAD.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were maximum walking distance or time (MWD/T) on the treadmill, six-minute walk test (6MWT) total distance, and pain-free walking distance or time (PFWD/T) on the treadmill. Our secondary outcomes were changes in the ankle-branchial index, all-cause mortality, changes in health-related quality-of-life scores, reintervention rates, and changes in subjective measures of physical function. We analysed continuous data by determining the mean difference (MD) and 95% confidence interval (CI), and dichotomous data by determining the odds ratio (OR) with corresponding 95% CI. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We identified seven studies involving 376 participants. All studies involved participants who received either additional supervised exercise or standard care after lower limb revascularisation. The studies' exercise programmes varied, and included supervised treadmill walking, combined exercise, and circuit training. The duration of exercise therapy ranged from six weeks to six months; follow-up time ranged from six weeks to five years. Standard care also varied between studies, including no treatment or advice to stop smoking, lifestyle modifications, or best medical treatment. We classified all studies as having some risk of bias concerns. The certainty of the evidence was very low due to the risk of bias, inconsistency, and imprecision. The meta-analysis included only a subset of studies due to concerns regarding data reporting, heterogeneity, and bias in most published research. The evidence was of very low certainty for all the review outcomes. Meta-analysis comparing changes in maximum walking distance from baseline to end of follow-up showed no improvement (MD 159.47 m, 95% CI -36.43 to 355.38; I2 = 0 %; 2 studies, 89 participants). In contrast, exercise may improve the absolute maximum walking distance at the end of follow-up compared to standard care (MD 301.89 m, 95% CI 138.13 to 465.65; I2 = 0 %; 2 studies, 108 participants). Moreover, we are very uncertain if there are differences in the changes in the six-minute walk test total distance from baseline to treatment end between exercise and standard care (MD 32.6 m, 95% CI -17.7 to 82.3; 1 study, 49 participants), and in the absolute values at the end of follow-up (MD 55.6 m, 95% CI -2.6 to 113.8; 1 study, 49 participants). Regarding pain-free walking distance, we are also very uncertain if there are differences in the mean changes in PFWD from baseline to treatment end between exercise and standard care (MD 167.41 m, 95% CI -11 to 345.83; I2 = 0%; 2 studies, 87 participants). We are very uncertain if there are differences in the absolute values of ankle-brachial index at the end of follow-up between the intervention and standard care (MD 0.01, 95% CI -0.11 to 0.12; I2 = 62%; 2 studies, 110 participants), in mortality rates at the end of follow-up (OR 0.92, 95% CI 0.42 to 2.00; I2 = 0%; 6 studies, 346 participants), health-related quality of life at the end of follow-up for the physical (MD 0.73, 95% CI -5.87 to 7.33; I2 = 64%; 2 studies, 105 participants) and mental component (MD 1.04, 95% CI -6.88 to 8.95; I2 = 70%; 2 studies, 105 participants) of the 36-item Short Form Health Survey. Finally, there may be little to no difference in reintervention rates at the end of follow-up between the intervention and standard care (OR 0.91, 95% CI 0.23 to 3.65; I2 = 65%; 5 studies, 252 participants).

AUTHORS' CONCLUSIONS

There is very uncertain evidence that additional exercise therapy after successful lower limb revascularisation may improve absolute maximal walking distance at the end of follow-up compared to standard care. Evidence is also very uncertain about the effects of exercise on pain-free walking distance, six-minute walk test distance, quality of life, ankle-brachial index, mortality, and reintervention rates. Although it is not possible to confirm the effectiveness of supervised exercise compared to standard care for all outcomes, studies did not report any harm to participants from this intervention after lower limb revascularisation. Overall, the evidence incorporated into this review was very uncertain, and additional evidence is needed from large, well-designed, randomised controlled studies to more conclusively demonstrate the role additional exercise therapy has after lower limb revascularisation in people with PAD.

Evidence for clinician underprescription of and patient non-adherence to guideline-recommended cardiovascular medications among adults with peripheral artery disease: protocol for a systematic review and meta-analysis

INTRODUCTION

International guidelines recommend that adults with peripheral artery disease (PAD) be prescribed antiplatelet, statin and antihypertensive medications. However, it is unclear how often people with PAD are underprescribed these drugs, which characteristics predict clinician underprescription of and patient non-adherence to guideline-recommended cardiovascular medications, and whether underprescription and non-adherence are associated with adverse health and health system outcomes.

METHODS AND ANALYSIS

We will search MEDLINE, EMBASE and Evidence-Based Medicine Reviews from 2006 onwards. Two investigators will independently review abstracts and full-text studies. We will include studies that enrolled adults and reported the incidence and/or prevalence of clinician underprescription of or patient non-adherence to guideline-recommended cardiovascular medications among people with PAD; adjusted risk factors for underprescription of/non-adherence to these medications; and adjusted associations between underprescription/non-adherence to these medications and outcomes. Outcomes will include mortality, major adverse cardiac and limb events (including revascularisation procedures and amputations), other reported morbidities, healthcare resource use and costs. Two investigators will independently extract data and evaluate study risk of bias. We will calculate summary estimates of the incidence and prevalence of clinician underprescription/patient non-adherence across studies. We will also conduct subgroup meta-analyses and meta-regression to determine if estimates vary by country, characteristics of the patients and treating clinicians, population-based versus non-population-based design, and study risks of bias. Finally, we will calculate pooled adjusted risk factors for underprescription/non-adherence and adjusted associations between underprescription/non-adherence and outcomes. We will use Grading of Recommendations, Assessment, Development and Evaluation to determine estimate certainty.

ETHICS AND DISSEMINATION

Ethics approval is not required as we are studying published data. This systematic review will synthesise existing evidence regarding clinician underprescription of and patient non-adherence to guideline-recommended cardiovascular medications in adults with PAD. Results will be used to identify evidence-care gaps and inform where interventions may be required to improve clinician prescribing and patient adherence to prescribed medications.

PROSPERO REGISTRATION NUMBER

CRD42022362801.

Antiplatelet agents for the treatment of adults with COVID-19

BACKGROUND

Severe coronavirus disease 2019 (COVID-19) can cause thrombotic events that lead to severe complications or death. Antiplatelet agents, such as acetylsalicylic acid, have been shown to effectively reduce thrombotic events in other diseases: they could influence the course of COVID-19 in general.

OBJECTIVES

To assess the efficacy and safety of antiplatelets given with standard care compared to no treatment or standard care (with/without placebo) for adults with COVID-19.

SEARCH METHODS

We searched the Cochrane COVID-19 Study Register (which comprises MEDLINE (PubMed), Embase, ClinicalTrials.gov, WHO ICTRP, medRxiv, CENTRAL), Web of Science, WHO COVID-19 Global literature on coronavirus disease and the Epistemonikos COVID-19 L*OVE Platform to identify completed and ongoing studies without language restrictions to December 2022.

SELECTION CRITERIA

We followed standard Cochrane methodology. We included randomised controlled trials (RCTs) evaluating antiplatelet agents for the treatment of COVID-19 in adults with COVID-19, irrespective of disease severity, gender or ethnicity.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodology. To assess bias in included studies, we used the Cochrane risk of bias tool (RoB 2) for RCTs. We rated the certainty of evidence using the GRADE approach for the outcomes.

MAIN RESULTS

Antiplatelets plus standard care versus standard care (with/without placebo) Adults with a confirmed diagnosis of moderate to severe COVID-19 We included four studies (17,541 participants) that recruited hospitalised people with a confirmed diagnosis of moderate to severe COVID-19. A total of 8964 participants were analysed in the antiplatelet arm (either with cyclooxygenase inhibitors or P2Y12 inhibitors) and 8577 participants in the control arm. Most people were older than 50 years and had comorbidities such as hypertension, lung disease or diabetes. The studies were conducted in high- to lower middle-income countries prior to wide-scale vaccination programmes. Antiplatelets compared to standard care: - probably result in little to no difference in 28-day mortality (risk ratio (RR) 0.95, 95% confidence interval (CI) 0.85 to 1.05; 3 studies, 17,249 participants; moderate-certainty evidence). In absolute terms, this means that for every 177 deaths per 1000 people not receiving antiplatelets, there were 168 deaths per 1000 people who did receive the intervention (95% CI 151 to 186 per 1000 people); - probably result in little to no difference in worsening (new need for invasive mechanical ventilation or death up to day 28) (RR 0.95, 95% CI 0.90 to 1.01; 2 studies, 15,266 participants; moderate-certainty evidence); - probably result in little to no difference in improvement (participants discharged alive up to day 28) (RR 1.00, 95% CI 0.96 to 1.04; 2 studies, 15,454 participants; moderate-certainty evidence); - probably result in a slight reduction of thrombotic events at longest follow-up (RR 0.90, 95% CI 0.80 to 1.02; 4 studies, 17,518 participants; moderate-certainty evidence); - may result in a slight increase in serious adverse events at longest follow-up (Peto odds ratio (OR) 1.57, 95% CI 0.48 to 5.14; 1 study, 1815 participants; low-certainty evidence), but non-serious adverse events during study treatment were not reported; - probably increase the occurrence of major bleeding events at longest follow-up (Peto OR 1.68, 95% CI 1.29 to 2.19; 4 studies, 17,527 participants; moderate-certainty evidence). Adults with a confirmed diagnosis of asymptomatic SARS-CoV-2 infection or mild COVID-19 We included two RCTs allocating participants, of whom 4209 had confirmed mild COVID-19 and were not hospitalised. A total of 2109 participants were analysed in the antiplatelet arm (treated with acetylsalicylic acid) and 2100 participants in the control arm. No study included people with asymptomatic SARS-CoV-2 infection. Antiplatelets compared to standard care: - may result in little to no difference in all-cause mortality at day 45 (Peto OR 1.00, 95% CI 0.45 to 2.22; 2 studies, 4209 participants; low-certainty evidence); - may slightly decrease the incidence of new thrombotic events up to day 45 (Peto OR 0.37, 95% CI 0.09 to 1.46; 2 studies, 4209 participants; low-certainty evidence); - may make little or no difference to the incidence of serious adverse events up to day 45 (Peto OR 1.00, 95% CI 0.60 to 1.64; 1 study, 3881 participants; low-certainty evidence), but non-serious adverse events were not reported. The evidence is very uncertain about the effect of antiplatelets on the following outcomes (compared to standard care plus placebo): - admission to hospital or death up to day 45 (Peto OR 0.79, 95% CI 0.57 to 1.10; 2 studies, 4209 participants; very low-certainty evidence); - major bleeding events up to longest follow-up (no event occurred in 328 participants; very low-certainty evidence). Quality of life and adverse events during study treatment were not reported.

AUTHORS' CONCLUSIONS

In people with confirmed or suspected COVID-19 and moderate to severe disease, we found moderate-certainty evidence that antiplatelets probably result in little to no difference in 28-day mortality, clinical worsening or improvement, but probably result in a slight reduction in thrombotic events. They probably increase the occurrence of major bleeding events. Low-certainty evidence suggests that antiplatelets may result in a slight increase in serious adverse events. In people with confirmed COVID-19 and mild symptoms, we found low-certainty evidence that antiplatelets may result in little to no difference in 45-day mortality and serious adverse events, and may slightly reduce thrombotic events. The effects on the combined outcome admission to hospital or death up to day 45 and major bleeding events are very uncertain. Quality of life was not reported. Included studies were conducted in high- to lower middle-income settings using antiplatelets prior to vaccination roll-outs. We identified a lack of evidence concerning quality of life assessments, adverse events and people with asymptomatic infection. The 14 ongoing and three completed, unpublished RCTs that we identified in trial registries address similar settings and research questions as in the current body of evidence. We expect to incorporate the findings of these studies in future versions of this review.

Diabetic foot ulcer: Challenges and future

Diabetic foot ulcers (DFUs) have become one of the important causes of mortality and morbidity in patients with diabetes, and they are also a common cause of hospitalization, which places a heavy burden on patients and society. The prevention and treatment of DFUs requires multidisciplinary management. By controlling various risk factors, such as blood glucose levels, blood pressure, lipid levels and smoking cessation, local management of DFUs should be strengthened, such as debridement, dressing, revascularization, stem cell decompression and oxygen therapy. If necessary, systemic anti-infection treatment should be administered. We reviewed the progress in the clinical practice of treating DFUs in recent years, such as revascularization, wound repair, offloading, stem cell transplantation, and anti-infection treatment. We also summarized and prospectively analyzed some new technologies and measurements used in the treatment of DFUs and noted the future challenges and directions for the development of DFU treatments.

Cilostazol for intermittent claudication

BACKGROUND

Peripheral arterial disease (PAD) affects between 4% and 12% of people aged 55 to 70 years, and 20% of people over 70 years. A common complaint is intermittent claudication (exercise-induced lower limb pain relieved by rest). These patients have a three- to six-fold increase in cardiovascular mortality.  Cilostazol is a drug licensed for the use of improving claudication distance and, if shown to reduce cardiovascular risk, could offer additional clinical benefits. This is an update of the review first published in 2007.

OBJECTIVES

To determine the effect of cilostazol on initial and absolute claudication distances, mortality and vascular events in patients with stable intermittent claudication.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, and AMED databases, and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registries, on 9 November 2020.

SELECTION CRITERIA

We considered double-blind, randomised controlled trials (RCTs) of cilostazol versus placebo, or versus other drugs used to improve claudication distance in patients with stable intermittent claudication.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trials for selection and independently extracted data. Disagreements were resolved by discussion. We assessed the risk of bias with the Cochrane risk of bias tool. Certainty of the evidence was evaluated using GRADE. For dichotomous outcomes, we used odds ratios (ORs) with corresponding 95% confidence intervals (CIs) and for continuous outcomes we used mean differences (MDs) and 95% CIs. We pooled data using a fixed-effect model, or a random-effects model when heterogeneity was identified. Primary outcomes were initial claudication distance (ICD) and quality of life (QoL). Secondary outcomes were absolute claudication distance (ACD), revascularisation, amputation, adverse events and cardiovascular events.

MAIN RESULTS

We included 16 double-blind, RCTs (3972 participants) comparing cilostazol with placebo, of which five studies also compared cilostazol with pentoxifylline. Treatment duration ranged from six to 26 weeks. All participants had intermittent claudication secondary to PAD. Cilostazol dose ranged from 100 mg to 300 mg; pentoxifylline dose ranged from 800 mg to 1200 mg. The certainty of the evidence was downgraded by one level for all studies because publication bias was strongly suspected. Other reasons for downgrading were imprecision, inconsistency and selective reporting. Cilostazol versus placebo Participants taking cilostazol had a higher ICD compared with those taking placebo (MD 26.49 metres; 95% CI 18.93 to 34.05; 1722 participants; six studies; low-certainty evidence). We reported QoL measures descriptively due to insufficient statistical detail within the studies to combine the results; there was a possible indication in improvement of QoL in the cilostazol treatment groups (low-certainty evidence). Participants taking cilostazol had a higher ACD compared with those taking placebo (39.57 metres; 95% CI 21.80 to 57.33; 2360 participants; eight studies; very-low certainty evidence). The most commonly reported adverse events were headache, diarrhoea, abnormal stools, dizziness, pain and palpitations. Participants taking cilostazol had an increased odds of experiencing headache compared to participants taking placebo (OR 2.83; 95% CI 2.26 to 3.55; 2584 participants; eight studies; moderate-certainty evidence).Very few studies reported on other outcomes so conclusions on revascularisation, amputation, or cardiovascular events could not be made. Cilostazol versus pentoxifylline There was no difference detected between cilostazol and pentoxifylline for improving walking distance, both in terms of ICD (MD 20.0 metres, 95% CI -2.57 to 42.57; 417 participants; one study; low-certainty evidence); and ACD (MD 13.4 metres, 95% CI -43.50 to 70.36; 866 participants; two studies; very low-certainty evidence). One study reported on QoL; the study authors reported no difference in QoL between the treatment groups (very low-certainty evidence). No study reported on revascularisation, amputation or cardiovascular events. Cilostazol participants had an increased odds of experiencing headache compared with participants taking pentoxifylline at 24 weeks (OR 2.20, 95% CI 1.16 to 4.17; 982 participants; two studies; low-certainty evidence).

AUTHORS' CONCLUSIONS

Cilostazol has been shown to improve walking distance in people with intermittent claudication. However, participants taking cilostazol had higher odds of experiencing headache. There is insufficient evidence about the effectiveness of cilostazol for serious events such as amputation, revascularisation, and cardiovascular events. Despite the importance of QoL to patients, meta-analysis could not be undertaken because of differences in measures used and reporting. Very limited data indicated no difference between cilostazol and pentoxifylline for improving walking distance and data were too limited for any conclusions on other outcomes.

Control of modifiable risk factors and major adverse cardiovascular events in people with peripheral artery disease and diabetes

BACKGROUND

People with diabetes and peripheral artery disease (PAD) have a high risk of major adverse cardiovascular events (MACE). Prior research suggests that medical therapies aimed to control modifiable risk factors are poorly implemented in patients with PAD.

AIM

To examine the association between the control of modifiable risk factors, estimated by the novel PAD-medical score, and the incidence of MACE in people with PAD and diabetes.

METHODS

Participants were recruited from out-patient clinics if they had a diagnosis of both PAD and diabetes. Control of reversible risk factors was assessed by a new composite measure, the PAD-medical score. This score takes into account the control of low-density lipoprotein cholesterol, blood pressure, blood glucose, smoking and prescription of an anti-platelet. Participants were followed to record incidence of myocardial infarction, stroke and cardiovascular death (MACE). The association of PAD-medical score with MACE was assessed using Cox proportional hazard analyses adjusting for age, sex and prior history of ischemic heart disease and stroke.

RESULTS

Between 2002 and 2020, a total of 424 participants with carotid artery disease (n = 63), aortic or peripheral aneurysm (n = 121) or lower limb ischemia (n = 240) were prospectively recruited, and followed for a median duration (inter-quartile range) of 2.0 (0.2–4.4) years. Only 33 (7.8%) participants had the optimal PAD-medical score of five, with 318 (75%) scoring at least three out of five. There were 89 (21.0%) participants that had at least one MACE during the follow-up period. A one-unit higher PAD-medical score was associated with lower risk of MACE (HR = 0.79, 95%CI: 0.63-0.98) after adjusting for other risk factors.

CONCLUSION

The PAD-medical score provides a simple way to assess the control of modifiable risk factors targeted by medical management aimed to reduce the incidence of MACE.

Evidence-Based Recommendations for Medical Management of Peripheral Artery Disease

Patients with lower limb artery stenosis or occlusion (peripheral artery disease; PAD) have been determined to be at very high risk of both major adverse cardiovascular events, such as myocardial infarction and stroke, and major adverse limb events, such as amputation and requirement for artery surgery.

Effective medical management has been identified as key in reducing this risk; however, this is often poorly implemented in clinical practice. Thus, the aim of this narrative review was to summarize the current evidence on the medical management of PAD in order to inform clinicians and highlight recommendations for clinical practice. International guidelines, randomized controlled trials, and relevant systematic reviews and meta-analyses have been included in this study. The focus was the management of the key modifiable risk factors to mitigate possible adverse events through prescription of anti-platelet and anticoagulation drugs and medications to control low-density lipoprotein cholesterol, blood pressure, and diabetes and aid smoking cessation. The available evidence from randomized clinical trials provide a strong rationale for the need for holistic medical management programs that are effective in achieving uptake of these medical therapies in patients with PAD. In conclusion, people with PAD have some of the highest adverse event rates among those with cardiovascular diseases. Secondary preventive measures have been proven effective in reducing these adverse events; however, they remain to be adequately implemented. Thus, the need for an effective implementation program has emerged to reduce adverse events in this patient group.

Pentoxifylline for intermittent claudication

BACKGROUND

Intermittent claudication (IC) is a symptom of peripheral arterial disease (PAD) and is associated with high morbidity and mortality. Pentoxifylline, one of many drugs used to treat IC, acts by decreasing blood viscosity, improving erythrocyte flexibility, and promoting microcirculatory flow and tissue oxygen concentration. Many studies have evaluated the efficacy of pentoxifylline in treating people with PAD, but results of these studies are variable. This is the second update of a review first published in 2012.

OBJECTIVES

To determine the efficacy of pentoxifylline in improving the walking capacity (i.e. pain-free walking distance and total (absolute, maximum) walking distance) of people with stable intermittent claudication, Fontaine stage II.

SEARCH METHODS

For this update, the Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases, and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 28 January 2020. There were no language restrictions.

SELECTION CRITERIA

We included all double-blind, randomised controlled trials (RCTs) comparing pentoxifylline versus placebo or any other pharmacological intervention in people with IC Fontaine stage II.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion, assessed the included studies, matched data and resolved disagreements by discussion. Review authors assessed the methodological quality of studies using the Cochrane 'Risk of bias' tool and collected results related to the outcomes of interest, pain-free walking distance (PFWD), total walking distance (TWD), ankle-brachial pressure index (ABI), quality of life (QoL) and side effects. Comparison of studies was based on duration and dose of pentoxifylline. We used GRADE criteria to assess the certainty of the evidence.

MAIN RESULTS

We identified no new eligible studies for this update. This review includes 24 studies with 3377 participants. Seventeen studies compared pentoxifylline versus placebo. The seven remaining studies compared pentoxifylline with flunarizine (one study), aspirin (one study), Gingko biloba extract (one study), nylidrin hydrochloride (one study), prostaglandin E1 (two studies), and buflomedil and nifedipine (one study). Risk of bias for the individual studies was generally unclear because there was a lack of methodological reporting for many of the included studies, especially regarding randomisation and allocation methods. Most included studies did not provide adequate information to allow selective reporting to be judged and did not report blinding of assessors. Heterogeneity between included studies was considerable with regards to multiple variables, including duration of treatment, dose of pentoxifylline, baseline walking distance and participant characteristics; therefore, pooled analysis for comparisons which included more than one study, was not possible. Pentoxifylline compared to placebo Of 17 studies comparing pentoxifylline with placebo, 11 reported PFWD and 14 reported TWD; the difference in percentage improvement in PFWD for pentoxifylline over placebo ranged from -33.8% to 73.9% and in TWD ranged from 1.2% to 155.9%. It was not possible to pool the data of the studies because data were insufficient and findings from individual trials were unclear. Most included studies suggested a possible improvement in PFWD and TWD for pentoxifylline over placebo (both low-certainty evidence). The five studies which evaluated pre-exercise ABI comparing pentoxifylline and placebo found no evidence of a difference (moderate-certainty evidence). Two of the three studies that evaluated QoL between people who received pentoxifylline and placebo were larger studies that used validated QoL tools and generally found no evidence of a difference between groups. One small, short-term study, which did not specify which QoL tool was used, reported improved QoL in the pentoxifylline group (moderate-certainty evidence). Pentoxifylline generally was well tolerated; the most commonly reported side effects consisted of gastrointestinal symptoms such as nausea (low-certainty evidence). Certainty of the evidence from this review was low or moderate, with downgrading due to risk of bias concerns, inconsistencies between studies and the inability to evaluate imprecision because meta-analysis could not be undertaken. The seven remaining studies compared pentoxifylline with either flunarizine, aspirin, Gingko biloba extract, nylidrin hydrochloride, prostaglandin E1, or buflomedil and nifedipine; data were too limited to allow any meaningful conclusions to be made.

AUTHORS' CONCLUSIONS

There is a lack of high-certainty evidence for the effects of pentoxifylline compared to placebo, or other treatments, for IC. There is low-certainty evidence that pentoxifylline may improve PFWD and TWD compared to placebo, but no evidence of a benefit to ABI or QoL (moderate-certainty evidence). Pentoxifylline was reported to be generally well tolerated (low-certainty evidence). Given the large degree of heterogeneity between the studies, the role of pentoxifylline for people with IC Fontaine class II remains uncertain.

Underuse of Cardiovascular Medications in Individuals With Known Lower Extremity Peripheral Artery Disease: HCHS/SOL

Background

Underuse of cardiovascular medications for secondary prevention among individuals with peripheral artery disease (PAD) has been reported. Little is known about PAD treatment status in the Hispanic/Latino population in the United States, who may have limited access to health care and who have worse clinical outcomes than non‐Hispanic individuals.

Methods and Results

We studied the use of cardiovascular therapies in 1244 Hispanic/Latino individuals recruited from 4 sites in the United States, including 826 individuals who reported diagnosis of PAD by physician and 418 individuals with coronary artery disease alone, in the Hispanic Community Health Study/Study of Latinos. We compared the prevalence of using antiplatelet therapy, lipid‐lowering therapy and antihypertensive therapy by PAD and coronary artery disease status. Among those with PAD, we studied factors associated with taking cardiovascular medications, including demographic and socioeconomic factors, acculturation, access to health care and comorbidities, using multivariable regression models. The overall prevalence for individuals with PAD taking antiplatelet therapy, lipid‐lowering therapy and, among hypertensive individuals, antihypertensive therapy was 31%, 26% and 57%, respectively. Individuals of Mexican background had the lowest use for all classes of cardiovascular medications. Older age, number of doctor visits and existing hypertension and diabetes mellitus were significantly associated with taking cardiovascular therapies in adjusted models. Compared with those with PAD alone, individuals with PAD and concurrent coronary artery disease were 1.52 (95% CI, 1.20–1.93) and 1.74 (1.30–2.32) times more likely to use antiplatelet agents and statins according to multivariable analysis. No significant difference of antihypertensive medication use was found among PAD patients with or without coronary artery disease.

Conclusions

Hispanic/Latino individuals with known PAD underuse cardiovascular medications recommended in clinical guidelines. More efforts should be directed to improve treatment in this important group.

Rivaroxaban and Aspirin in Peripheral Vascular Disease: a Review of Implementation Strategies and Management of Common Clinical Scenarios

PURPOSE OF REVIEW

Peripheral artery disease (PAD) affects an estimated 200 million people worldwide and is associated with significant cardiovascular morbidity and mortality. Cardiovascular risk is further increased among individuals with polyvascular disease, where either cerebrovascular or coronary artery disease is present in addition to PAD. In this review, we present common clinical scenarios encountered when managing patients with PAD and provide an evidence-based approach to prescribing optimal antithrombotics in this population.

RECENT FINDINGS

The COMPASS trial recently demonstrated that rivaroxaban 2.5 mg BID + ASA daily significantly reduces major adverse cardiac and limb events in patients with PAD. Despite these advances, morbidity following MALE events remains high. With widespread approval by federal health regulators, the COMPASS regimen should be strongly considered in PAD patients who do not have a high bleeding risk. Implementing the COMPASS regimen in patients with PAD, along with other vascular risk reduction strategies, will have a substantial impact on reducing atherothromboembolic risk in patients with established vascular disease.

Lumbar sympathectomy can improve symptoms associated with ischaemia, vasculitis, diabetic neuropathy and hyperhidrosis affecting the lower extremities-a single-centre experience

BACKGROUND

Lumbar sympthectomy (LS) was traditionally performed for intermittent claudication but is now eclipsed by revascularisation for that indication. However, it retains a role in the management of critical limb ischaemia and other conditions causing lower limb pain with or without ischaemia. We report the role of LS in modern surgical practice when revascularisation and pain management options have been exhausted.

METHODS

A medical chart review was performed on all patients who underwent LS in our unit from 2005 to 2016 (inclusive). Symptomatology, surgical indications and patient outcomes were reported.

RESULTS

Twenty-seven cases were performed in total (21 unilateral, 3 bilateral). Underlying diagnoses were as follows: PAD [59.3% (n = 16)], hyperhidrosis [18.5% (n = 5)] and equal numbers of complex regional pain syndrome, diabetic neuropathy and vasculitis [7.4% (n = 2) each]. Overall, 85.2% (n = 23) had improvement or resolution of symptoms at 1 month and 70.3% (n = 19) had persistent improvement of symptoms at 1 year. Non-PAD patients had superior outcomes with 90.9% (n = 10) reporting improved symptomatology at 1 month and nearly three quarters [72.8% (n = 8)] maintaining this improvement at 1 year. Only four patients required subsequent major amputation, all in the severe PAD group.

CONCLUSION

Lumbar sympathectomy can improve symptoms associated with ischaemia, vasculitis, diabetic neuropathy and hyperhidrosis. Non-PAD patients have the greatest benefit.

Clopidogrel plus aspirin versus aspirin alone for preventing cardiovascular events

BACKGROUND

Aspirin is the prophylactic antiplatelet drug of choice for people with cardiovascular disease. Adding a second antiplatelet drug to aspirin may produce additional benefit for people at high risk and people with established cardiovascular disease. This is an update to a previously published review from 2011.

OBJECTIVES

To review the benefit and harm of adding clopidogrel to aspirin therapy for preventing cardiovascular events in people who have coronary disease, ischaemic cerebrovascular disease, peripheral arterial disease, or were at high risk of atherothrombotic disease, but did not have a coronary stent.

SEARCH METHODS

We updated the searches of CENTRAL (2017, Issue 6), MEDLINE (Ovid, 1946 to 4 July 2017) and Embase (Ovid, 1947 to 3 July 2017) on 4 July 2017. We also searched ClinicalTrials.gov and the WHO ICTRP portal, and handsearched reference lists. We applied no language restrictions.

SELECTION CRITERIA

We included all randomised controlled trials comparing over 30 days use of aspirin plus clopidogrel with aspirin plus placebo or aspirin alone in people with coronary disease, ischaemic cerebrovascular disease, peripheral arterial disease, or at high risk of atherothrombotic disease. We excluded studies including only people with coronary drug-eluting stent (DES) or non-DES, or both.

DATA COLLECTION AND ANALYSIS

We collected data on mortality from cardiovascular causes, all-cause mortality, fatal and non-fatal myocardial infarction, fatal and non-fatal ischaemic stroke, major and minor bleeding. The overall treatment effect was estimated by the pooled risk ratio (RR) with 95% confidence interval (CI), using a fixed-effect model (Mantel-Haenszel); we used a random-effects model in cases of moderate or severe heterogeneity (I2 ≥ 30%). We assessed the quality of the evidence using the GRADE approach. We used GRADE profiler (GRADE Pro) to import data from Review Manager to create a 'Summary of findings' table.

MAIN RESULTS

The search identified 13 studies in addition to the two studies in the previous version of our systematic review. Overall, we included data from 15 trials with 33,970 people. We completed a 'Risk of bias' assessment for all studies. The risk of bias was low in four trials because they were at low risk of bias for all key domains (random sequence generation, allocation concealment, blinding, selective outcome reporting and incomplete outcome data), even if some of them were funded by the pharmaceutical industry.Analysis showed no difference in the effectiveness of aspirin plus clopidogrel in preventing cardiovascular mortality (RR 0.98, 95% CI 0.88 to 1.10; participants = 31,903; studies = 7; moderate quality evidence), and no evidence of a difference in all-cause mortality (RR 1.05, 95% CI 0.87 to 1.25; participants = 32,908; studies = 9; low quality evidence).There was a lower risk of fatal and non-fatal myocardial infarction with clopidogrel plus aspirin compared with aspirin plus placebo or aspirin alone (RR 0.78, 95% CI 0.69 to 0.90; participants = 16,175; studies = 6; moderate quality evidence). There was a reduction in the risk of fatal and non-fatal ischaemic stroke (RR 0.73, 95% CI 0.59 to 0.91; participants = 4006; studies = 5; moderate quality evidence).However, there was a higher risk of major bleeding with clopidogrel plus aspirin compared with aspirin plus placebo or aspirin alone (RR 1.44, 95% CI 1.25 to 1.64; participants = 33,300; studies = 10; moderate quality evidence) and of minor bleeding (RR 2.03, 95% CI 1.75 to 2.36; participants = 14,731; studies = 8; moderate quality evidence).Overall, we would expect 13 myocardial infarctions and 23 ischaemic strokes be prevented for every 1000 patients treated with the combination in a median follow-up period of 12 months, but 9 major bleeds and 33 minor bleeds would be caused during a median follow-up period of 10.5 and 6 months, respectively.

AUTHORS' CONCLUSIONS

The available evidence demonstrates that the use of clopidogrel plus aspirin in people at high risk of cardiovascular disease and people with established cardiovascular disease without a coronary stent is associated with a reduction in the risk of myocardial infarction and ischaemic stroke, and an increased risk of major and minor bleeding compared with aspirin alone. According to GRADE criteria, the quality of evidence was moderate for all outcomes except all-cause mortality (low quality evidence) and adverse events (very low quality evidence).

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

BACKGROUND

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.

OBJECTIVES

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.

SEARCH METHODS

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.

SELECTION CRITERIA

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.

DATA COLLECTION AND ANALYSIS

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.

MAIN RESULTS

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.

AUTHORS' CONCLUSIONS

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.

Management of Critical Limb Ischemia

Critical limb ischemia (CLI) is a clinical syndrome of ischemic pain at rest or tissue loss, such as nonhealing ulcers or gangrene, related to peripheral artery disease. CLI has a high short-term risk of limb loss and cardiovascular events. Noninvasive or invasive angiography help determine the feasibility and approach to arterial revascularization. An endovascular-first approach is often advocated based on a lower procedural risk; however, specific patterns of disease may be best treated by open surgical revascularization. Balloon angioplasty and stenting form the backbone of endovascular techniques, with drug-eluting stents and drug-coated balloons offering low rates of repeat revascularization. Combined antegrade and retrograde approaches can increase success in long total occlusions. Below the knee, angiosome-directed angioplasty may lead to greater wound healing, but failing this, any straight-line flow into the foot is pursued. Hybrid surgical techniques such as iliac stenting and common femoral endarterectomy are commonly used to reduce operative risk. Lower extremity bypass grafting is most successful with a good quality, long, single-segment autogenous vein of at least 3.5-mm diameter. Minor amputations are often required for tissue loss as a part of the treatment strategy. Major amputations (at or above the ankle) limit functional independence, and their prevention is a key goal of CLI therapy. Medical therapy after revascularization targets risk factors for atherosclerosis and assesses wound healing and new or recurrent flow-limiting disease. The ongoing National Institutes of Health-sponsored Best Endovascular Versus Best Surgical Therapy in Patients With Critical Limb Ischemia (BEST-CLI) study is a randomized trial of the contemporary endovascular versus open surgical techniques in patients with CLI.

Pentoxifylline for intermittent claudication

BACKGROUND

Intermittent claudication (IC) is a symptom of peripheral arterial disease (PAD) and is associated with high morbidity and mortality. Pentoxifylline, one of many drugs used to treat IC, acts by decreasing blood viscosity, improving erythrocyte flexibility and promoting microcirculatory flow and tissue oxygen concentration. Many studies have evaluated the efficacy of pentoxifylline in treating individuals with PAD, but results of these studies are variable. This is an update of a review first published in 2012.

OBJECTIVES

To determine the efficacy of pentoxifylline in improving the walking capacity (i.e. pain-free walking distance and total (absolute, maximum) walking distance) of individuals with stable intermittent claudication, Fontaine stage II.

SEARCH METHODS

For this update, the Cochrane Vascular Group Trials Search Co-ordinator searched the Specialised Register (last searched April 2015) and the Cochrane Register of Studies (2015, Issue 3).

SELECTION CRITERIA

All double-blind, randomised controlled trials (RCTs) comparing pentoxifylline versus placebo or any other pharmacological intervention in patients with IC Fontaine stage II.

DATA COLLECTION AND ANALYSIS

Two review authors separately assessed included studies,. matched data and resolved disagreements by discussion. Review authors assessed the methodological quality of studies by using the Cochrane 'Risk of bias' tool and collected results related to pain-free walking distance (PFWD) and total walking distance (TWD). Comparison of studies was based on duration and dose of pentoxifylline.

MAIN RESULTS

We included in this review 24 studies with 3377 participants. Seventeen studies compared pentoxifylline versus placebo. In the seven remaining studies, pentoxifylline was compared with flunarizine (one study), aspirin (one study), Gingko biloba extract (one study), nylidrin hydrochloride (one study), prostaglandin E1 (two studies) and buflomedil and nifedipine (one study). The quality of the evidence was generally low, with large variability in reported findings.. Most included studies did not report on random sequence generation and allocation concealment, did not provide adequate information to allow selective reporting to be judged and did not report blinding of assessors. Heterogeneity between included studies was considerable with regards to multiple variables, including duration of treatment, dose of pentoxifylline, baseline walking distance and participant characteristics; therefore, pooled analysis was not possible.Of 17 studies comparing pentoxifylline with placebo, 14 reported TWD and 11 reported PFWD; the difference in percentage improvement in TWD for pentoxifylline over placebo ranged from 1.2% to 155.9%, and in PFWD from -33.8% to 73.9%. Testing the statistical significance of these results generally was not possible because data were insufficient. Most included studies suggested improvement in PFWD and TWD for pentoxifylline over placebo and other treatments, but the statistical and clinical significance of findings from individual trials is unclear. Pentoxifylline generally was well tolerated; the most commonly reported side effects consisted of gastrointestinal symptoms such as nausea.

AUTHORS' CONCLUSIONS

Given the generally poor quality of published studies and the large degree of heterogeneity evident in interventions and in results, the overall benefit of pentoxifylline for patients with Fontaine class II intermittent claudication remains uncertain. Pentoxifylline was shown to be generally well tolerated.Based on total available evidence, high-quality data are currently insufficient to reveal the benefits of pentoxifylline for intermittent claudication.

Contemporary medical management of peripheral arterial disease: a focus on risk reduction and symptom relief for intermittent claudication

Peripheral arterial disease (PAD) is primarily caused by progressive systemic atherosclerosis manifesting in the lower extremities. This review addresses the epidemiology, clinical presentation and evaluation, and medical management of PAD, with a focus on intermittent claudication. Key advances in the recognition of cardiovascular risk in asymptomatic individuals with mildly abnormal ankle-brachial index, newer reflections on exercise therapy, and a review of established and investigational agents for the treatment of symptomatic PAD, such as cilostazol, statins, and angiotensin-converting enzyme inhibitors, are highlighted.

Peripheral Arterial Disease in Patients with Type 2 Diabetes Mellitus

Peripheral arterial disease (PAD) in patients with type 2 diabetes mellitus (T2DM) exhibits broad clinical characteristics and various consequences and is known as one of the major macrovascular complications of T2DM. Atherosclerosis is recognized as the most direct and important cause of PAD, but acute or chronic limb ischemia may be the result of various risk factors. In light of the increasing number of patients who undergo peripheral vascular procedures, the number of subjects who are exposed to the risks for PAD and related complications is increasing. In this review, we will discuss the clinical and epidemiological characteristics of PAD, as well as the clinical significance of PAD in T2DM subjects.

Pharmacology in peripheral arterial disease: what the interventional radiologist needs to know

Peripheral arterial disease (PAD) is a progressive disease with significant morbidity and mortality. Risk factor control, using diet and lifestyle modification, exercise, and pharmacological methods, improves symptoms and reduces associated cardiovascular events in these patients. Antiplatelet agents and anticoagulants may be used to reduce the incidence of acute events related to thrombosis. The armamentarium available for symptom relief and disease modification is discussed. Novel treatments such as therapeutic angiogenesis are in their evolutionary phase with promising preclinical data.

Clot strength is negatively associated with ambulatory function in patients with peripheral artery disease and intermittent claudication

Peripheral artery disease (PAD) is associated with exercise impairment and greater thrombotic risk. We investigated whether clot formation and platelet aggregation assessed by thromboelastography and light-transmission aggregometry correlate with the severity of symptomatic PAD assessed by ambulatory function measures. We studied 40 symptomatic patients with PAD in whom severity of disease was assessed using ankle-brachial index, peak walking time (PWT), claudication onset time, peak oxygen uptake, daily ambulatory activity, and walking impairment questionnaire (WIQ) scores. Clot strength correlated negatively with peak oxygen uptake, PWT, WIQ distance, and stair-climbing scores. Time to clot formation did not correlate with exercise parameters. Platelet aggregation was negatively correlated with WIQ distance score and was positively correlated with PWT and peak oxygen uptake. In conclusion, clot strength and platelet aggregation correlated with objective and self-perceived ambulatory measures. Patients with PAD having more severe walking impairment may be likely to form stronger clots.

Healthcare quality indicators of peripheral artery disease based on systematic reviews

OBJECTIVES

Peripheral artery disease (PAD) is a major health problem whose clinical management includes multiple options regarding risk factor control, diagnosis, and medical and surgical treatment. The aim was to generate indicators based on systematic reviews to evaluate the quality of healthcare provided in PAD.

METHODS

Electronic searches were run for systematic reviews in The Cochrane Library (Issue 6, 2011), MEDLINE, EMBASE, and other databases (up to June 2011). Conclusive systematic reviews of high methodological quality were selected to formulate clinical recommendations. Indicators were derived from clinical recommendations with moderate to very high strength of evidence as assessed by the GRADE system.

RESULTS

From 1,804 reviews initially identified, 29 conclusive and high-quality systematic reviews were selected and nine clinical recommendations were formulated with a moderate to very high strength of recommendation. Six indicators were finally generated: four on pharmacological interventions, antiplatelet agents, naftidrofuryl, cilostazol, and statins; and two lifestyle interventions, exercise and tobacco cessation. No indicators were derived for diagnostic tests or surgical techniques. Most indicators targeted patients with intermittent claudication.

CONCLUSIONS

These quality indicators will help clinicians to assess the appropriateness of healthcare provided in PAD. The development of evidence-based indicators in PAD is limited by the lack of methodological quality of the research in this disease, the inconclusiveness of the evidence on diagnostic and surgical techniques, and the dynamic nature of the vascular diseases field.

Screen or not to screen for peripheral arterial disease: guidance from a decision model

Background

Asymptomatic Peripheral Arterial Disease (PAD) is associated with greater risk of acute cardiovascular events. This study aims to determine the cost-effectiveness of one time only PAD screening using Ankle Brachial Index (ABI) test and subsequent anti platelet preventive treatment (low dose aspirin or clopidogrel) in individuals at high risk for acute cardiovascular events compared to no screening and no treatment using decision analytic modelling.

Methods

A probabilistic Markov model was developed to evaluate the life time cost-effectiveness of the strategy of selective PAD screening and consequent preventive treatment compared to no screening and no preventive treatment. The analysis was conducted from the Dutch societal perspective and to address decision uncertainty, probabilistic sensitivity analysis was performed. Results were based on average values of 1000 Monte Carlo simulations and using discount rates of 1.5% and 4% for effects and costs respectively. One way sensitivity analyses were performed to identify the two most influential model parameters affecting model outputs. Then, a two way sensitivity analysis was conducted for combinations of values tested for these two most influential parameters.

Results

For the PAD screening strategy, life years and quality adjusted life years gained were 21.79 and 15.66 respectively at a lifetime cost of 26,548 Euros. Compared to no screening and treatment (20.69 life years, 15.58 Quality Adjusted Life Years, 28,052 Euros), these results indicate that PAD screening and treatment is a dominant strategy. The cost effectiveness acceptability curves show 88% probability of PAD screening being cost effective at the Willingness To Pay (WTP) threshold of 40000 Euros. In a scenario analysis using clopidogrel as an alternative anti-platelet drug, PAD screening strategy remained dominant.

Conclusion

This decision analysis suggests that targeted ABI screening and consequent secondary prevention of cardiovascular events using low dose aspirin or clopidogrel in the identified patients is a cost-effective strategy. Implementation of targeted PAD screening and subsequent treatment in primary care practices and in public health programs is likely to improve the societal health and to save health care costs by reducing catastrophic cardiovascular events.

A review of the role of anticoagulation in the treatment of peripheral arterial disease

Peripheral arterial disease (PAD) is a major medical/surgical problem associated with high risk for coronary heart disease (CHD). Anticoagulation plays a significant role in the management of the PAD patient. However, evidence-based medicine supports only select anticoagulants, mainly antiplatelet agents. The available anticoagulant classes, their individual medications, and the mechanisms of action are described. Dextran 40, platelet glycoprotein (GP) IIb/IIIa receptor antagonists, direct thrombin (factor IIa, FIIa) inhibitors, and factor Xa (FXa) inhibitors do not, at this juncture, appear to have a significant role to play in the PAD patient. Aspirin has been used in PAD patients for a few decades, as has warfarin, but the role of warfarin is very limited. An attempt has been made to place each medication and its function in context all the way to the present with oral direct thrombin (FIIa) and FXa inhibitors described. These inhibitors may ultimately play an, as yet, undefined role in PAD. Specific use of anticoagulants in PAD patients is described and aspirin still stands out as a fundamental therapy. The thienopyridines, especially clopidogrel, have their established place and there is some evidence for benefit from the use of clopidogrel in dual therapy with aspirin. Dipyridamole, especially with aspirin as dual therapy, and cilostazol also have their evidence-based niches. The main role played by warfarin is for the patient with a vein graft in the arterial circulation. Heparin retains significant procedural importance. For now, Class I, Level of Evidence A center around aspirin for the PAD patient with clopidogrel, an alternative agent.

The role of oral vitamin K antagonists in the outcome of infrainguinal bypass procedures

We investigated the role of oral vitamin K antagonists (VKAs) in graft patency, limb salvage, major and minor bleeding rates in patients undergoing infrainguinal bypass surgery. Five randomized-controlled trials (RCTs; n = 3746 patients) comparing VKA versus non-VKA treatment outcomes in patients undergoing infrainguinal bypass surgery were analyzed. The VKA treatment was associated with improved graft patency rates when a vein graft was used (risk ratio [RR]: 0.74; P = .0004), while there was no difference with prosthetic grafts (RR: 1.07; P = .39). The VKA treatment was also associated with improved limb salvage rates (RR: 0.33; P = .0008). Major and minor bleeding complications were higher in the VKA group. In conclusion, VKA treatment is associated with improved graft patency and limb salvage rates when a vein graft is used at the price of an increased risk of bleeding. Due to the inconsistent results, further well-designed RCTs are needed.

Etiologies of intracerebral hematomas

Intracerebral hemorrhage (ICH) remains a life-threatening disease that carries significant morbidity and mortality despite recent diagnostic and management advances. Various conditions are associated with increased risk of intracerebral hemorrhage. Understanding the etiology of these conditions and their pathophysiological contribution to ICH will likely lead to better therapeutic and preventative measures and improve the morbidity and mortality associated with intracerebral hemorrhage. We will review the current literature regarding important etiologies/risk factors of intracerebral hemorrhage.

Pentoxifylline for intermittent claudication

BACKGROUND

Intermittent claudication (IC) is a symptom of peripheral arterial occlusive disease (PAD). It is associated with high morbidity and mortality. Pentoxifylline is one of many drugs used to treat IC. Pentoxifylline decreases blood viscosity, improves erythrocyte flexibility, and increases microcirculatory flow and tissue oxygen concentration.Many studies have evaluated the efficacy of pentoxifylline in treating PAD but the results of these studies are very variable.

OBJECTIVES

To determine the efficacy of pentoxifylline in improving the walking capacity (that is pain-free walking distance and the total (absolute, maximum) walking distance) of patients with stable intermittent claudication, Fontaine stage II.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group searched their Specialised Register (last searched January 2011) and CENTRAL (2011, Issue 1). In addition, we searched MEDLINE (Week 2 January 2011) and EMBASE (2011 Week 03). ClinicalTrials.gov and Current Controlled Trials were searched for ongoing or unpublished trials.

SELECTION CRITERIA

All double blind, randomised controlled trials (RCTs) comparing pentoxifylline to placebo or any other pharmacological intervention in patients with IC Fontaine stage II.

DATA COLLECTION AND ANALYSIS

Included studies were assessed separately by two review authors. Data were matched and disagreements resolved by discussion. The quality of the studies was assessed using the Jadad score and the Cochrane risk of bias tool. Results relating to pain-free walking distance (PFWD) and total walking distance (TWD) were collected. Studies were compared based on the duration and dose of pentoxifylline.

MAIN RESULTS

Twenty-three studies with 2816 participants were included in this review. There was considerable heterogeneity between the included studies with regards to multiple variables including duration of treatment, dose of pentoxifylline, baseline walking distance and patient characteristics, and therefore pooled analysis was not possible. The quality of the included studies was generally low. There was very large variability in the reported findings between the individual studies. In a total of 17 studies which compared pentoxifylline with placebo, of which 14 reported TWD and 11 reported PFWD, the difference in percentage improvement in TWD for pentoxifylline over placebo ranged from 1.2% to 155.9%, and for PFWD the difference ranged from -33.8% to 73.9%. Testing for statistical significance of these results was generally not possible due to the lack of data. There was no statistically significant difference in ankle brachial pressure index (ABI) between the pentoxifylline and placebo groups. Pentoxifylline was generally well tolerated.

AUTHORS' CONCLUSIONS

Given the generally poor quality of the published studies and the large degree of heterogeneity in the interventions and the results, the overall benefit of pentoxifylline for patients with Fontaine class II intermittent claudication remains uncertain. Pentoxifylline is generally well tolerated.  Based on the totality of the available evidence, it is possible that pentoxifylline could have a place in the treatment of IC as a means of improving walking distance and as a complimentary treatment assuming all other essential measures such as lifestyle change, exercise and treatment for secondary prevention have been taken into account. However, the response to pentoxifylline should be assessed on an individual basis.