Tailored risk assessment and forecasting in intermittent claudication.

BACKGROUND: Guidelines recommend cardiovascular risk reduction and supervised exercise therapy as the first line of treatment in intermittent claudication, but implementation challenges and poor patient compliance lead to significant variation in management and therefore outcomes. The development of a precise risk stratification tool is proposed through a machine-learning algorithm that aims to provide personalized outcome predictions for different management strategies. METHODS: Feature selection was performed using the least absolute shrinkage and selection operator method. The model was developed using a bootstrapped sample based on patients with intermittent claudication from a vascular centre to predict chronic limb-threatening ischaemia, two or more revascularization procedures, major adverse cardiovascular events, and major adverse limb events. Algorithm performance was evaluated using the area under the receiver operating characteristic curve. Calibration curves were generated to assess the consistency between predicted and actual outcomes. Decision curve analysis was employed to evaluate the clinical utility. Validation was performed using a similar dataset. RESULTS: The bootstrapped sample of 10 000 patients was based on 255 patients. The model was validated using a similar sample of 254 patients. The area under the receiver operating characteristic curves for risk of progression to chronic limb-threatening ischaemia at 2 years (0.892), risk of progression to chronic limb-threatening ischaemia at 5 years (0.866), likelihood of major adverse cardiovascular events within 5 years (0.836), likelihood of major adverse limb events within 5 years (0.891), and likelihood of two or more revascularization procedures within 5 years (0.896) demonstrated excellent discrimination. Calibration curves demonstrated good consistency between predicted and actual outcomes and decision curve analysis confirmed clinical utility. Logistic regression yielded slightly lower area under the receiver operating characteristic curves for these outcomes compared with the least absolute shrinkage and selection operator algorithm (0.728, 0.717, 0.746, 0.756, and 0.733 respectively). External calibration curve and decision curve analysis confirmed the reliability and clinical utility of the model, surpassing traditional logistic regression. CONCLUSION: The machine-learning algorithm successfully predicts outcomes for patients with intermittent claudication across various initial treatment strategies, offering potential for improved risk stratification and patient outcomes.

High INtensity Interval Training in pATiEnts with Intermittent Claudication: A Qualitative Acceptability Study.

BACKGROUND: A novel high-intensity interval training (HIIT) program has demonstrated feasibility for patients with intermittent claudication (IC). The aim of this study was to explore patient perspectives of the HIIT program to inform refinement and future research. METHODS: All patients screened and eligible for the 'high intensity interval training in patients with intermittent claudication (INITIATE)' study were eligible to take part in a semistructured interview. A convenience subsample of patients was selected from 3 distinct groups: 1) those who completed the HIIT program, 2) those who prematurely discontinued the HIIT program, and 3) those who declined the HIIT program. Interviews considered patients views of the program and experiences of undertaking and/or being invited to undertake it. Interviews were audio recorded, transcribed verbatim, and analyzed via thematic analysis. RESULTS: Eleven out of 31 participants who completed the program and 12 out of 38 decliners were interviewed. No participants who withdrew from the program agreed to interview. The 3 key themes were; personal reflections of the program; program facilitators and barriers; and perceived benefits. Completers enjoyed taking part, reported symptomatic improvement and would complete it again. Practical and psychological barriers exist, such as transport and motivation. Changes to the program were suggested. CONCLUSIONS: Findings support the acceptability of this novel HIIT program, which in combination with the feasibility findings, suggest that a fully powered randomized controlled trial, comparing HIIT to usual-care supervised exercise programs is warranted.

A preoperative supervised exercise program potentially improves long-term survival after elective abdominal aortic aneurysm repair.

OBJECTIVE: A preoperative supervised exercise program (SEP) improves cardiorespiratory fitness and perioperative outcomes for patients undergoing elective abdominal aortic aneurysm (AAA) repair. The aim of this study was to assess the effect of a preoperative SEP on long-term survival of these patients. A secondary aim was to consider long-term changes in cardiorespiratory fitness and quality of life. METHODS: Patients scheduled for open or endovascular AAA repair were previously randomized to either a 6-week preoperative SEP or standard management, and a significant improvement in a composite outcome of cardiac, pulmonary, and renal complications was seen following SEP. For the current analysis, patients were followed up to 5 years post-surgery. The primary outcome for this analysis was all-cause mortality. Data were analyzed on an intention to treat (ITT) and per protocol (PP) basis, with the latter meaning that patients randomized to SEP who did not attend any sessions were excluded. The PP analysis was further interrogated using a complier average causal effect (CACE) analysis on an all or nothing scale, which adjusts for compliance. Additionally, patients who agreed to follow-up attended the research center for cardiopulmonary exercise testing and/or provided quality of life measures. RESULTS: ITT analysis demonstrated that the primary endpoint occurred in 24 of the 124 participants at 5 years, with eight in the SEP group and 16 in the control group (P = .08). The PP analysis demonstrated a significant survival benefit associated with SEP attendance (4 vs 16 deaths; P = .01). CACE analysis confirmed a significant intervention effect (hazard ratio, 0.36; 95% confidence interval, 0.16-0.90; P = .02). There was no difference between groups for cardiorespiratory fitness measures and most quality of life measures. CONCLUSIONS: These novel findings suggest a long-term mortality benefit for patients attending a SEP prior to elective AAA repair. The underlying mechanism remains unknown, and this merits further investigation.

Supervised Exercise Therapy for Intermittent Claudication: A Propensity Score Matched Analysis of Retrospective Data on Long Term Cardiovascular Outcomes.

OBJECTIVE: This study aimed to explore the long term outcomes of patients with intermittent claudication (IC) who completed supervised exercise therapy (SET) vs. those who declined or prematurely discontinued SET, focusing on the incidence of chronic limb threatening ischaemia (CLTI), revascularisation, major adverse limb events (MALE), and major adverse cardiovascular events (MACE). METHODS: A retrospective registry analysis of consecutive patients with IC who were referred for SET between March 2015 and August 2016 and followed up for a minimum of five years. Serial univariable analysis and logistic regression were performed to identify the statistically significant clinical variables that were independent predictors of each outcome measure. The resulting statistically significant variables were used to guide 1:1 propensity score matching (PSM) using the nearest neighbour method with a calliper of 0.2. Cox proportional hazards regression was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for the association between SET and the outcomes of interest. RESULTS: Two hundred and sixty-six patients were referred to SET between March 2015 and August 2016. Of these, 64 patients completed SET and 202 patients did not. After PSM, 49 patients were analysed in each cohort. The Cox proportional hazards analysis revealed a significant association between completion of SET and revascularisation requirement (HR 0.46 95% CI 0.25 - 0.84; p = .011), completion of SET and progression to CLTI (HR 0.091, 95% CI 0.04 - 0.24; p < .001), completion of SET and MACE (HR 0.52; 95% CI 0.28 - 0.99; p = .05) and completion of SET and MALE (HR 0.28, 95% CI 0.13 - 0.65; p = .003). The Harrell's C index for all of these models was greater than 0.75, indicating good predictive accuracy. CONCLUSION: Completion of SET is associated with better outcomes in patients who completed SET compared with patients who declined or discontinued SET with respect to clinically important cardiovascular outcomes over seven years.

Neuromuscular Electrical Stimulation for Intermittent Claudication (NESIC): multicentre, randomized controlled trial.

METHODS: This was an open, multicentre, randomized controlled trial. Patients with intermittent claudication attending vascular surgery outpatient clinics were randomized (1:1) to receive either neuromuscular electrical stimulation (NMES) or not in addition to local standard care available at study centres (best medical therapy alone or plus supervised exercise therapy (SET)). The objective of this trial was to investigate the clinical efficacy of an NMES device in addition to local standard care in improving walking distances in patients with claudication. The primary outcome was change in absolute walking distance, measured by a standardized treadmill test at 3 months. Secondary outcomes included intermittent claudication (IC) distance, adherence, quality of life, and haemodynamic changes. RESULTS: Of 200 participants randomized, 160 were included in the primary analysis (intention to treat, Tobit regression model). The square root of absolute walking distance was analysed (due to a right-skewed distribution) and, although adjunctive NMES improved it at 3 months, no statistically significant effect was observed. SET as local standard care seemed to improve distance compared to best medical therapy at 3 months (3.29 units; 95 per cent c.i., 1.77 to 4.82; P < 0.001). Adjunctive NMES improved distance in mild claudication (2.88 units; 95 per cent c.i., 0.51 to 5.25; P = 0.02) compared to local standard care at 3 months. No serious adverse events relating to the device were reported. CONCLUSION: Supervised exercise therapy is effective and NMES may provide further benefit in mild IC.This trial was supported by a grant from the Efficacy and Mechanism Evaluation Program, a Medical Research Council and National Institute for Health and Care Research partnership. Trial registration: ISRCTN18242823.

Patients with intermittent claudication experience pain in their legs during walking or exercise which ends with rest. This severely impairs physical activity and quality of life. Treatment for such patients typically involves best medical therapy, which includes exercise advice. This study aimed to determine whether a neuromuscular electrical stimulation device improved the walking distance of patients with intermittent claudication compared to local standard care available (which may include supervised exercise therapy) in a trial. Supervised exercise improved walking distances but there was no difference in those that received a device in this patient group.

High-intensity interval training in patients with intermittent claudication.

OBJECTIVE: Provision, uptake, adherence, and completion rates for supervised exercise programs (SEP) for intermittent claudication (IC) are low. A shorter, more time-efficient, 6-week, high-intensity interval training (HIIT) program may be an effective alternative that is more acceptable to patients and easier to deliver. The aim of this study was to determine the feasibility of HIIT for patients with IC. METHODS: A single arm proof-of-concept study, performed in secondary care, recruiting patients with IC referred to usual-care SEPs. Supervised HIIT was performed three times per week for 6 weeks. The primary outcome was feasibility and tolerability. Potential efficacy and potential safety were considered, and an integrated qualitative study was undertaken to consider acceptability. RESULTS: A total of 280 patients were screened: 165 (59%) were eligible, and 40 (25%) were recruited. The majority (n = 31; 78%) of participants completed the HIIT program. The remaining nine patients were withdrawn or chose to withdraw. Completers attended 99% of training sessions, completed 85% of sessions in full, and performed 84% of completed intervals at the required intensity. There were no related serious adverse events. Maximum walking distance (+94 m; 95% confidence interval, 66.6-120.8 m) and the SF-36 physical component summary (+2.2; 95% confidence interval, 0.3-4.1) were improved following completion of the program. CONCLUSIONS: Uptake to HIIT was comparable to SEPs in patients with IC, but completion rates were higher. HIIT appears feasible, tolerable, and potentially safe and beneficial for patients with IC. It may provide a more readily deliverable, acceptable form of SEP. Research comparing HIIT with usual-care SEPs appears warranted.

Clinical outcomes following mechanochemical ablation of superficial venous incompetence compared with endothermal ablation: meta-analysis.

BACKGROUND: Mechanochemical ablation (MOCA) is an alternative method to endovenous thermal ablation (EVTA) for the treatment of superficial venous incompetence that does not require tumescent anaesthesia. The aim of this study was to compare the outcomes from RCTs of MOCA versus EVTA. METHODS: A search was conducted in MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL). Meta-analysis inclusion was restricted to RCTs comparing MOCA against EVTA. Outcomes included anatomical occlusion rate, disease-specific quality of life using the Aberdeen Varicose Vein Questionnaire, procedural and postprocedural pain, and rates of venous thromboembolism. RESULTS: Four RCTs were included in the meta-analysis comprising 654 patients. The anatomical occlusion rate at 1 year was lower after MOCA than EVTA (risk ratio 0.85, 95 per cent c.i. 0.78 to 0.91; P < 0.001). No significant differences were detected in procedural pain (mean difference -3.25, -14.25 to 7.74; P = 0.560) or postprocedural pain (mean difference -0.63, -2.15 to 0.89; P = 0.420). There were no significant differences in Aberdeen Varicose Vein Questionnaire score at 1 year (mean difference 0.06, -0.50 to 0.62; P = 0.830) or in incidence of venous thromboembolism (risk ratio 0.72, 95 per cent c.i. 0.14 to 3.61; P = 0.690). CONCLUSION: The rate of successful anatomical occlusion after MOCA is significantly lower than that after EVTA, but there is no difference in procedural and postprocedural pain between the two interventions. Long-term data are required to assess the impact of the reduced vein occlusion rate on clinical outcomes such as quality of life and reintervention.

The current first-line treatment for varicose veins uses heat to block the diseased veins and is called endovenous thermal ablation (EVTA). Mechanochemical ablation (MOCA) is an alternative method of treatment using a chemical and a fast-spinning wire to block the veins instead. The potential benefits of MOCA include less pain and fewer complications. The aim of this study was to identify high-quality clinical trials comparing MOCA with EVTA, and to assess any differences in the results of treatment. The results showed that MOCA was less successful in blocking the diseased veins than EVTA. There were no differences in the amount of pain or discomfort during or after the procedures (which was low). At 1 year, those treated with both techniques reported the same quality of life. Both techniques were effective over 1 year in terms of improving quality of life; however, the potential benefits of MOCA were not clearly proven in the trials, and the poorer rates of successfully blocking the veins may cause the varicose veins to come back sooner, or the quality-of-life improvement to be shorter lived. There was no evidence to support MOCA replacing EVTA as the first-line treatment in the majority of patients, but it is a viable treatment for selected people.

Extracorporeal shockwave therapy for diabetic foot ulcers: a feasibility study.

OBJECTIVE: The purpose of this study was to assess the feasibility of delivering extracorporeal shockwave therapy (ESWT) to patients with diabetic foot ulcers (DFUs). It also aimed to explore any potential clinical effect of ESWT on wound healing and investigate whether ESWT offers any patient-reported benefits. METHOD: In this single-centre, mixed methods feasibility study, patients with a DFU who met the eligibility criteria underwent ESWT three times over a seven-day period. Primary outcome was feasibility of delivering the intervention. Secondary outcomes included wound size, number of DFUs healed at 12 weeks and quality of life (QoL). Semi-structured interviews explored participants' experience of undergoing ESWT. RESULTS: Of 106 patients screened, 24 (22.6%) were recruited. Following recruitment, two patients were withdrawn from the study with 22 patients included in the final analysis. The mean attendance at clinic was 90.9% and 65.1% for follow-up. The mean score for acceptability and tolerability was 9.86±0.48 (95% confidence interval (CI): 9.62-10.01) and 9.15±2.57 (95% CI: 7.87-10.42), respectively. There were no serious adverse events or side-effects. Of the DFUs, 45.5% healed during follow-up and QoL scores improved until eight weeks. Key themes identified from the qualitative interviews were: desire for fast healing; improved QoL; flexibility of new treatments; and accessibility of transport. CONCLUSION: This study has shown that it is possible to recruit and retain patents into a single-arm study of ESWT for DFUs. This study supports development of a large randomised control trial to determine the clinical and cost-effectiveness of ESWT for DFU healing.

Provision of NICE-recommended varicose vein treatment in the NHS.

BACKGROUND: Standardization of access to treatment and compliance with clinical guidelines are important to ensure the delivery of high-quality care to people with varicose veins. In the National Health Service (NHS) in England, commissioning of care for people with varicose veins is performed by Clinical Commissioning Groups (CCGs) and clinical guidelines have been developed by the National Institute for Health and Care Excellence (NICE CG168). The Evidence-Based Intervention (EBI) programme was introduced in the NHS with the aim of improving care quality and supporting implementation of NICE CG168. The aim of this study was to assess access to varicose vein treatments in the NHS and the impact of EBI. METHODS: CCG policies for the delivery of varicose vein treatments in the NHS in England were obtained from 2017 (before EBI introduction) and 2019 (after EBI introduction) and categorized by two independent reviewers into levels of compliance with NICE CG168. Hospital Episode Statistics data were compared with the NICE commissioning model predictions. A quality-adjusted life-year was valued at £20 000 (Euro 23 000 15 November 2022). RESULTS: Despite the introduction of the EBI programme, CCG compliance with NICE CG168 fell from 34.0 per cent (64 of 191) to 29.0 per cent (55 of 191). Some 33.0 per cent of CCG policies (63 of 191) became less compliant and only 7.3 per cent (14 of 191) changed to become fully compliant. Overall, 66.5 per cent of CCGs (127 of 191) provided less than the recommended intervention rate before EBI and this increased to 73.3 per cent (140 of191) after EBI. The overall proportion of patients estimated to require treatment annually who received treatment fell from 44.0 to 37.0 per cent. The associated estimated loss in net health benefit was between £164 and 174 million (Euro 188 million and 199 million 15 November 2022) over 3 years. A compliant policy was associated with a higher intervention rate; however, commissioning policy was associated with only 16.8 per cent of the variation in intervention rate (R2 = 0.168, P < 0.001). CONCLUSION: Many local varicose vein commissioning policies in the NHS are not compliant with NICE CG168. More than half of patients who should be offered varicose vein treatment are not receiving it, and there is widespread geographical variation. The EBI programme has not been associated with any improvement in commissioning or access to varicose vein treatment.

Extracorporeal shockwave therapy compared with standard care for diabetic foot ulcer healing: An updated systematic review.

Emerging evidence suggests that extracorporeal shockwave therapy (ESWT) may improve time to DFU healing. The aim of this review was to appraise the evidence on role of ESWT in DFU healing and impact of different ESWT doses. Databases were searched for trials comparing ESWT plus standard care to standard care alone in participants with DFUs. Search results were reviewed by two independent reviewers. The Cochrane Risk of Bias 2 tool and GRADE approach was used to assess bias and certainty. The primary outcome was time to healing. The search identified 345 papers after duplicates removed. Six trials consisting of 471 participants were included. There was unclear or high risk of bias across all domains. Time to ulcer healing was probably shorter in patients treated with ESWT compared with standard ulcer care alone (GRADE: low certainty). Patients treated with ESWT were more likely to heal at 20 weeks post-ESWT compared with those treated with standard ulcer care alone (GRADE: low certainty). There was significant heterogeneity. ESWT remains a promising new treatment but the translation into routine clinical practice is still limited by the low certainty of evidence surrounding its effectiveness, case selection and optimum dose.

The Edinburgh Claudication Questionnaire has poor diagnostic accuracy in people with intermittent claudication.

BACKGROUND: The screening and diagnosis of intermittent claudication is a challenging process and often relies on the expertise of specialist vascular clinicians. We sought to investigate the diagnostic performance of the Edinburgh Claudication Questionnaire (ECQ) as a screening tool for referrals of suspected intermittent claudication from primary to secondary care. METHOD: Prospectively, 100 referrals from primary care with a stated diagnosis or query regarding intermittent claudication were recruited. All participants who completed the ECQ, underwent an anklebrachial pressure index (ABPI) assessment and treadmill exercise testing. Outcomes of the ECQ were compared to clinical diagnoses of intermittent claudication. RESULTS: The ECQ had a sensitivity of 46.8% (95% CI: 27-65%), specificity of 63.2% (95% CI: 43-82%) and accuracy of 53.0% (95% CI: 43-63%). The diagnostic performance was not changed by combining the ECQ with a positive ABPI or post-exercise ABPI outcome for PAD. CONCLUSION: The ECQ had a poor diagnostic performance in this cohort. Considering the results found here and in other recent studies, the utility of the ECQ as a screening tool and epidemiological survey tool must be questioned. Novel, low-resource diagnostic tools are needed in this population.

Long term outcomes of 'Christmas Tree' banding for haemodialysis access induced distal ischemia: A 13-year experience.

BACKGROUND: The reduction in distal arterial flow following arteriovenous fistula (AVF) creation can cause a perfusion deficit known as haemodialysis access induced distal ischemia (HAIDI). Various techniques have been advocated to treat this difficult problem with varying success. We present the long-term outcomes following a novel banding technique. METHODS: 46 patients in this cohort from 2008 to 2021 underwent a novel banding procedure using a Dacron™ patch shaped with one slit-end and saw-tooth edges (resulting in a 'Christmas-tree' pattern) to provide a ratchet mechanism to progressively constrict the fistula outflow. Real-time finger perfusion pressure monitoring allowed an accurate reduction in AVF flow whilst increasing distal arterial perfusion pressure. Baseline characteristic were recorded and Kaplan-Meier survival curves were obtained to calculate the post-intervention primary, assisted primary and secondary patency. RESULTS: 29 patients presented with rest pain and 11 presented with tissue loss due to distal ischemia. The post-intervention primary access patency was 100%, 98%, 78% and 61% at 30, 60 and 180 days and 1 year respectively. Complete resolution of symptoms was achieved in 74% (n = 34) of patients and a partial response needing no further intervention was achieved in 11% (n = 5) of patients. A Youden index calculation suggested that digital pressures of 41 mm Hg or lower in an open AVF were highly sensitive for symptomatic hand ischemia whereas pressures greater than 65 mm Hg ruled out distal ischemia. CONCLUSION: 'Christmas-tree' banding with on table finger systolic pressures is not only an efficacious and durable method for treating HAIDI but also preserves fistula patency.

The local physiological effects of a single-use topical negative pressure device in healthy volunteers: the PICO-1 study.

OBJECTIVE: This study aimed to investigate the effects of a single-use negative pressure wound therapy (sNPWT) device on tissue perfusion, oxygenation and pressure in the intact skin of healthy volunteers. METHOD: Healthy volunteers wore a PICO sNPWT device (Smith+Nephew, UK) on their right medial calf for one week. Perfusion, tissue oxygenation and tissue pressure were recorded in superficial and deep tissues over a period of seven days. At the baseline visit, measurements were recorded before and after dressing application without activation. Macrovascular flow and transduced needle pressure measures were recorded at 0 minutes, 30 minutes and 60 minutes after device activation. Superficial tissue perfusion and both oxygenation measures were recorded continuously over the hour following activation. All outcome measures were repeated at 24 hours and again after seven days, both with the dressing and following dressing removal. RESULTS: The device was associated with a measurable increase in perfusion of the limb in 12 healthy volunteers. Superficial tissue oxygenation adjacent to the dressing was reduced during wear, while deeper tissue demonstrated an increase in oxygenation levels. Superficial skin perfusion was observed to differ between skin overlying muscle and that overlying bone. Pressure in tissue underneath the dressing pad was increased throughout dressing wear and returned to baseline levels on dressing removal. CONCLUSION: sNPWT produced measurable changes in local physiology in healthy volunteers with intact skin, despite the absence of a wound. Effects may differ according to anatomical site and the composition of underlying tissues. Other factors that promote healing were not explored in this study. DECLARATION OF INTEREST: This study was funded by Smith+Nephew investigator-initiated grant IIS 684. The funder had no input into study design, conduct, analysis, manuscript preparation or dissemination. The authors have no conflicts of interest to declare.

An updated systematic review and meta-analysis of home-based exercise programs for individuals with intermittent claudication.

OBJECTIVE: Supervised exercise programs (SEP) are effective for improving walking distance in patients with intermittent claudication (IC) but provision and uptake rates are suboptimal. Access to such programs has also been halted by the Coronavirus pandemic. The aim of this review is to provide a comprehensive overview of the evidence for home-based exercise programs (HEP). METHODS: This review was conducted in according with the published protocol and PRISMA guidance. Medline, EMBASE, CINAHL, PEDro, and Cochrane CENTRAL were searched for terms relating to HEP and IC. Randomized and nonrandomized trials that compared HEP with SEP, basic exercise advice, or no exercise controls for IC were included. A narrative synthesis was provided for all studies and meta-analyses conducted using data from randomized trials. The primary outcome was maximal walking distance. Subgroup analyses were performed to consider the effect of monitoring. Risk of bias was assessed using the Cochrane tool and quality of evidence via GRADE. RESULTS: We included 23 studies with 1907 participants. Considering the narrative review, HEPs were inferior to SEPs which was reflected in the meta-analysis (mean distance [MD], 139 m; 95% confidence interval [CI], 45-232 m; P = .004; very low quality of evidence). Monitoring was an important component, because HEPs adopting this strategy were equivalent to SEPs (MD, 8 m; 95% CI, -81 to 97; P = .86; moderate quality of evidence). For HEPs vs basic exercise advice, narrative review suggested HEPs can be superior, although not always significantly so. For HEPs vs no exercise controls, narrative review and meta-analysis suggested HEPs were potentially superior (MD, 136 m; 95% CI, -2 to 273 m; P = .05; very low quality of evidence). Monitoring was also a key element in these comparisons. Other elements such as appropriate frequency (≥3× a week), intensity (to moderate-maximum pain), duration (20 progressing to 60 minutes) and type (walking) of exercise were important, as was education, self-regulation, goal setting, feedback, and action planning. CONCLUSIONS: When SEPs are unavailable, HEPs are recommended. However, to elicit maximum benefit they should be structured, incorporating all elements of our evidence-based recommendations.

Considering the Feasibility, Tolerability, and Safety of High-Intensity Interval Training as a Novel Treatment for Patients With Intermittent Claudication.

PURPOSE: This study assessed the feasibility, tolerability, safety, and potential efficacy of a novel, 6-wk, high-intensity interval training (HIIT) program for patients with intermittent claudication (IC). METHODS: Patients referred to a usual-care supervised exercise program were invited to undertake a HIIT program. All recruited patients performed a baseline cardiopulmonary exercise test (CPX) to inform their exercise prescription. HIIT involved 10, 1-min high-intensity cycling intervals interspersed with 1-min recovery intervals, performed 3 d/wk for 6 wk. Outcomes included feasibility, tolerability, safety, walking distance, and quality of life. RESULTS: A total of 144 patients with IC were referred, 95 met initial eligibility criteria (66%) and 30 (32%) were recruited for HIIT, of which 15 (50%) completed. Of the recruited patients, 90% were on optimal medical therapy and 40% had concomitant cardiac, cerebrovascular, and/or respiratory disease. Patients who completed the program attended 100% of the sessions and one serious adverse event was recorded. Improvements in walking distances and quality of life were observed. Following recruitment of the first 20 patients, the inclusion criteria were refined on the basis of CPX, leading to improved completion rates. CONCLUSIONS: This study provides preliminary findings indicating that patients with IC can complete a short-term HIIT program. We provide very early evidence that HIIT may be safe and well-tolerated. In addition, walking distances seem to improve following HIIT. After a small change in the exclusion criteria, the intervention and inclusion/exclusion criteria now seem appropriate for this population, meaning further research to evaluate HIIT in patients with IC is warranted.

Exercise training for intermittent claudication: a narrative review and summary of guidelines for practitioners.

Peripheral artery disease (PAD) is caused by atherosclerotic narrowing of the arteries supplying the lower limbs often resulting in intermittent claudication, evident as pain or cramping while walking. Supervised exercise training elicits clinically meaningful benefits in walking ability and quality of life. Walking is the modality of exercise with the strongest evidence and is recommended in several national and international guidelines. Alternate forms of exercise such as upper- or lower-body cycling may be used, if required by certain patients, although there is less evidence for these types of programmes. The evidence for progressive resistance training is growing and patients can also engage in strength-based training alongside a walking programme. For those unable to attend a supervised class (strongest evidence), home-based or 'self-facilitated' exercise programmes are known to improve walking distance when compared to simple advice. All exercise programmes, independent of the mode of delivery, should be progressive and individually prescribed where possible, considering disease severity, comorbidities and initial exercise capacity. All patients should aim to accumulate at least 30 min of aerobic activity, at least three times a week, for at least 3 months, ideally in the form of walking exercise to near-maximal claudication pain.

Presurgery exercise-based conditioning interventions (prehabilitation) in adults undergoing lower limb surgery for peripheral arterial disease.

BACKGROUND: Lower limb peripheral arterial disease (PAD) is a type of cardiovascular disease where the blood vessels that carry the blood to the legs are hardened and narrowed. The most severe manifestation of PAD is critical limb ischaemia (CLI). This condition results in symptoms of intractable rest pain, non-healing wounds and ulceration, gangrene or both. PAD affects more than 200 million people worldwide and approximately 3% to 5% of people aged over 40 have PAD, rising to 18% in people over 70 years of age. Between 5% to 10% of symptomatic PAD patients will progress to CLI over a five-year period and the five year cumulative incidence rate for asymptomatic patients with PAD deteriorating to intermittent claudication is 7%, with 21% of these progressing to CLI. Treatment options include angioplasty, bypass or amputation of the limb, when life or limb is threatened. People with CLI have a high risk of mortality and morbidity. The mortality rates during a surgical admission are approximately 5%. Within one year of surgery, the mortality rate rises to 22%. Postoperative complications are as high as 30% and readmission rates vary between 7% to 18% in people with CLI. Despite recent advances in surgical technology, anaesthesia and perioperative care, a proportion of surgical patients have a suboptimal recovery. Presurgery conditioning (prehabilitation) is a multimodal conditioning intervention carried out prior to surgery using a combination of exercise, with or without nutritional or psychological interventions, or both. The use of prehabilitation is gaining momentum, particularly in elderly patients undergoing surgery and patients undergoing colorectal cancer surgery, as a means of optimising fitness to improve the prognosis for people undergoing the physiological stress of surgery. People with PAD are characterised by poor mobility and physical function and have a lower level of fitness as a result of disease progression. Therefore, prehabilitation may be an opportunity to improve their recovery following surgery. However, as multimodal prehabilitation requires considerable resources, it is important to assess whether it is superior to usual care. This review aimed to compare prehabilitation with usual care (defined as a preoperative assessment, including blood and urine tests). The key outcomes were postoperative complications, mortality and readmissions within 30 days of the surgical procedure, and one-year survival rates. OBJECTIVES: To assess the effectiveness of prehabilitation (preoperative exercise, either alone or in combination with nutritional or psychological interventions, or both) on postoperative outcomes in adults with PAD undergoing open lower limb surgery. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials register to 25 September 2019. SELECTION CRITERIA: We considered all published and unpublished randomised controlled trials (RCTs) comparing presurgery interventions and usual care. Primary outcomes were postoperative complications, mortality and readmission to hospital within 30 days of the surgical procedure. DATA COLLECTION AND ANALYSIS: Two review authors independently reviewed all records identified by the searches conducted by the Cochrane Vascular Information Specialist. We planned to undertake data collection and analysis in accordance with recommendations described in the Cochrane Handbook for Systematic Reviews of Interventions. MAIN RESULTS: We found no RCTs that met the inclusion criteria for this review. AUTHORS' CONCLUSIONS: We found no RCTs conducted to determine the effects of prehabilitation on mortality or other postoperative outcomes when compared to usual care for patients with PAD. As a consequence, we were unable to provide any evidence to guide the treatment of patients with PAD undergoing surgery. To perform a randomised controlled trial of presurgery conditioning would be challenging but trials are warranted to provide solid evidence on this topic.

A systematic review of high-intensity interval training as an exercise intervention for intermittent claudication.

BACKGROUND: Intermittent claudication (IC) is the most common symptom of peripheral arterial disease, which significantly affects walking ability, functional capacity and quality of life. Supervised exercise programs (SEP) are recommended as first-line treatment, but recruitment and adherence rates are poor. The time required to complete a SEP is the most common barrier to participation cited by patients who decline. High-intensity interval training (HIIT) is more time efficient than current SEPs and therefore has the potential to overcome this barrier. We conducted a systematic review to appraise the evidence for HIIT programs for IC. METHODS: MEDLINE, Embase, and CENTRAL databases were searched for terms related to HIIT and IC. Randomized and nonrandomized trials that investigated HIIT for the treatment of IC were included, with no exclusions based on exercise modality, protocol, or use of a comparator arm. Outcome measures were walking distances, peak oxygen uptake, recruitment and adherence rates, and quality of life. The risk of bias was assessed using the Cochrane tool and study quality using a modified Physiotherapy Evidence Database scale. RESULTS: Nine articles reporting eight studies were included in the review. HIIT seems to improve walking distances and oxygen uptake in relation to controls, with improvements attainable in just 6 weeks. When HIIT was compared with low-intensity exercise, it seemed that longer low-intensity programs were required to obtain similar benefits to those from short-term HIIT. CONCLUSIONS: Initial evidence suggests that HIIT may provide benefits for patients with IC. Initially, pilot studies of low-volume, short-term HIIT vs usual SEPs are required. This strategy will allow for larger randomized, controlled trials to be appropriately designed and adequately powered to further explore the potential benefits of HIIT in IC.

A pilot feasibility randomised clinical trial comparing dialkylcarbamoylchloride-coated dressings versus standard care for the primary prevention of surgical site infection.

A surgical site infection (SSI) may occur in up to 30% of procedures and results in significant morbidity and mortality. We aimed to assess the feasibility of conducting a randomised controlled trial (RCT) examining the use of dialkylcarbamoylchloride (DACC)-impregnated dressings, which bind bacteria at the wound bed, in the prevention of SSI in primarily closed incisional wounds. This pilot RCT recruited patients undergoing clean or clean-contaminated vascular surgery. Participants were randomised intraoperatively on a 1:1 basis to either a DACC-coated dressing or a control dressing. Outcomes were divided into feasibility and clinical outcomes. The primary clinical outcome was SSI at 30 days (assessed using Centers for Disease Control criteria and Additional treatment, Serous discharge, Erythema, Purulent exudate, Separation of the deep tissues, Isolation of bacteria and duration of inpatient Stay scoring methods). This study recruited 144 patients in 12 months at a median rate of 10 per month. Eligibility was 73% and recruitment 60%. At 30 days, there was a 36.9% relative risk reduction in the DACC-coated arm (16.22% versus 25.71%, odds ratio 0.559, P = 0.161). The number needed to treat was 11 patients. A large-scale RCT is both achievable and desirable given the relative risk reduction shown in this study. Further work is needed to improve the study protocol and involve more centres in a full-scale RCT.