Critical Limb Ischemia in the Dialysis-Dependent Patient: Infrainguinal Vein Bypass Is Justified

The combination of critical limb ischemia and end-stage renal failure (ESRF, ie, dialysis- dependent) represents severe systemic atherosclerosis and is associated with a very poor medium-term survival. Many nephrologists and surgeons advocate primary amputation. We examined the recent experience in this unit to determine whether infrainguinal bypass in these patients can be justified. Retrospective study of all patients with critical limb ischemia and ESRF undergoing surgery in a regional vascular and renal unit between January 1996 and May 2003. Forty-two patients with ESRF (median age 65 years) were referred with critical limb ischemia. Seventeen patients underwent 24 (7 bilateral) infrainguinal bypasses (17 autologous vein, 7 polytetrafluoroethylene [PTFE] conduit; tissue loss in 21/24, 88%), and 25 patients had primary major amputations of 32 limbs. Early occlusion occurred in 5 grafts (21%, all 5/5 PTFE). In-hospital mortality was 13% in the bypass group, 24% in the amputation group. Median in-hospital stay was 59 days in the bypass group, 46 days in the amputation group. Thirty-day, 1- and 2-year survival was 88%, 50%, and 33% in the bypass group; 83%, 39%, and 35% in the amputation group. The limb salvage rate was 66% at 1 year. Seventy-five percent (18/24) of operated on limbs (15/17 of vein grafts) avoided major amputation at follow-up (median 18 months) or death. The combination of critical limb ischemia and end- stage renal failure carries a poor medium-term survival independent of primary amputation or surgical revascularization. Infrainguinal bypass in selected cases with vein conduit can, however, allow the majority of these patients to avoid major limb amputation.

A review of the main trials and registries: what we think we do and do not know about carotid artery stenting

Despite many randomised controlled trials there are none that recommend carotid artery stenting (CAS) replaces carotid endarterectomy (CEA) for preventing stroke in patients with atherosclerotic carotid artery stenosis. CAS continues to be attractive due to its minimally-invasive nature and potential benefit in those patients at 'high risk' during open surgery. The belief that CAS will replace CEA is likely misplaced; a complimentary role for each mode of treatment is a more realistic vision for the future. Assessment of the existing data may provide useful information as to the subgroups that have most to benefit from each treatment type, therefore allowing a patient-specific approach to the management of individual lesions. This knowledge, coupled with further advances in the techniques of open and endovascular surgery, will progress the application of CAS and better its results.

Robotically-steerable catheters and their role in the visceral aortic segment

In recent years, steerable catheter systems have been introduced into clinical practice for cardiac mapping and ablation procedures. As endovascular therapy is becoming more complex, more advanced and versatile catheter designs utilizing robotic technology may have a role in aortic and peripheral arterial interventions. This article discusses alternative steerable catheter designs focusing on robotic endovascular catheter technology. A comprehensive comparison, review and analysis of robotic versus manual techniques in the visceral segment are presented to reveal both their advantages and limitations. Preclinical studies and early experience suggest that robotically steerable endovascular catheters offer improved manoeuvrability at the catheter tip, enhanced positional control and "off-the-wall" centreline navigation in a remote-control fashion. These advanced systems have the potential to overcome some of the technical difficulties with manual catheter control, improve stability at key target areas, reduce the risk of vessel trauma, distal embolization and radiation exposure, whilst improving overall operator performance with short learning curves. Robotic catheter technology may be more suitable to complex and often unpredictable anatomy in the visceral segment and may offer a reliable platform for future applications involving device delivery or target intervention. This intuitive technology is rapidly evolving and still requires technological refinements to extend current capabilities. Clinical studies involving head-to-head comparisons with conventional techniques are essential for evaluating its long-term safety and efficacy.

Advanced catheter technology: is this the answer to overcoming the long learning curve in complex endovascular procedures

INTRODUCTION

Advanced endovascular procedures require a high degree of skill with a long learning curve. We aimed to identify differential increases in endovascular skill acquisition in novices using conventional (CC), manually steerable (MSC) and robotic endovascular catheters (RC).

MATERIALS/METHODS

10 novices cannulated all vessels within a CT-reconstructed pulsatile-flow arch phantom in the Simulated Endovascular Suite. Subjects were randomly assigned to conventional/manually-steerable/robotic techniques as the first procedure undertaken. The operators repeated the task weekly for 5 weeks. Quantitative (cannulation times, wire/catheter-tip movements, vessel wall hits) and qualitative metrics (validated rating scale (IC3ST)) were compared.

RESULTS

Subjects exhibited statistically significant differences when comparing initial to final performance for total procedure times and catheter-tip movements with all catheter types. Sequential non-parametric comparisons identified learning curve plateau levels at weeks 2 or 3(RCs, MSCs), and at week 4(CCs) for the majority of metrics. There were significantly fewer catheter-tip movements using advanced catheter technology after training (Week 5: CC 74 IQR(59-89) versus MSC 62(44-81); p = 0.028, and RC 33 (28-44); p = 0.012). RCs virtually eliminated wall hits at the arch (CC 29(28-76) versus RC 8(6-9); p = 0.005) and produced significantly higher overall performance scores (p < 0.02).

CONCLUSION

Advanced endovascular catheters, although more intricate, do not seem to take longer to master and in some areas offer clear advantages with regards to positional control, at a faster rate. RCs seem to be the most intuitive and advanced skill acquisition occurs with minimal training. Robotic endovascular technology may have a significantly shorter path to proficiency allowing an increased number of trainees to attempt more complex endovascular procedures earlier and with a greater degree of safety.

Identification of patient safety improvement targets in successful vascular and endovascular procedures: analysis of 251 hours of complex arterial surgery

OBJECTIVES

To investigate failures in patient safety for patients undergoing vascular and endovascular procedures to guide future quality and safety interventions.

DESIGN

Single centre prospective observational study.

METHODS

66 procedures (17 thoracoabdominal and 23 abdominal aortic aneurysms, 4 carotid and 22 limb procedures) were observed prospectively over a 9-month period (251 h operating time) by two trained observers. Event logs were recorded for each procedure. Two blinded experts identified and independently categorised failures into 22 types (using a validated category tool) and severity (5-point scale). Data are expressed as median (range). Statistical analysis was performed using Mann-Whitney U, Kruskal-Wallis and Spearman's Rank tests.

RESULTS

1145 failures were identified with good inter-assessor reliability (Cronbach's alpha 0.844). The commonest failure types related to equipment (including unavailability, configuration and other failures) (269/1145 [23.5%]) and communication (240/1145 [21.0%]). A comparatively lower number of technical and psychomotor failures were identified (103 [9.0%]). The number of failures correlated with procedure duration (rho = 0.695, p < 0.001) but not anatomical site of the procedure or pathology of the disease process. Failure rate was higher in patients undergoing combined surgical/endovascular procedures compared to open surgery (median 5.7/h [IQR 4.2-8.1] vs 3.0/h [2.5-3.5]; p < 0.001). The severity of failures was similar (1.5/5 [1-2] vs 1/5 [1-2] respectively; p = 0.095). For combined procedures, failure rates were significantly higher during the endovascular phase (9.6/h [7.5-13.7]) compared to the non-endovascular phase (3.0/h [1.0-5.0]; p < 0.001).

CONCLUSIONS

Failures in patient safety are common during complex arterial procedures. Few failures were severe, although minor failures during critical stages and accumulation of multiple minor failures may potentially be important. Failures occurred especially during the endovascular phase and were often related to equipment or communication aspects. Interventions to improve procedural safety and quality of care should primarily target these specific areas.

Training with simulation versus operative room attendance

Reduced training times, increasing complexity of endovascular and open vascular interventions and concerns for patient's safety have necessitated a modernisation in surgical training. A more strategic approach is required to facilitate the acquisition of surgical skills outside the operating room and to minimize the risks to patients as surgeons develop their technical expertise. Virtual reality simulation has been proposed as a means to train and objectively assess technical endovascular performance without risks to patient safety. This article reviews the evidence and the limitations for this adjunctive tool, the implementation in current training programmes and future applications to maintain the highest standards of care for treatment of vascular disease.

Recent advances in thoraco-abdominal aortic aneurysm repair

Thoraco-abdominal aortic aneurysm repair remains a formidable challenge to vascular surgeons. The traditional repair of thoraco-laparotomy with aortic cross-clamping is associated with a high morbidity and mortality despite significant advances in perioperative critical care, anaesthetic and surgical techniques. The advent of the endovascular revolution has shown a marked paradigm in the approach to all aneurysm repairs. As a logical progression from the open repair, the St Mary's visceral hybrid repair combines traditional open techniques (retrograde visceral and renal revascularisation via mid-line laparotomy) with endovascular stent grafting, thereby avoiding the need for thoracotomy and aortic cross-clamping. In specialist centres, the results have been encouraging and easily comparable to the open repair. The technique has been used in several centres around the world and represents a robust, transferrable method of repairing thoraco-abdominal aortic aneurysms. Stent-grafting technologies have reached a point of sophistication that wholly endovascular methods of repairing thoraco-abdominal aortic aneurysms are being performed in several centres around the world. Although these stent grafts have to be customised to the individual patient and are only suitable for certain types of aneurysmal anatomies, they represent the future of thoraco-abdominal aortic aneurysm repair. We review the history of thoraco-abdominal aortic aneurysm repair, the exciting advances in their treatment and discuss our approach to the management of thoraco-abdominal aortic aneurysms in the 21st century.

Concurrent colorectal malignancy and abdominal aortic aneurysm: a multicentre experience and review of the literature

OBJECTIVES

There is lack of consensus regarding concurrent vs. staged approaches, and the prioritisation of staged procedures in cases presenting with colorectal carcinoma (CRC) and abdominal aortic aneurysm (AAA) synchronously. We aim to present our experience, review the literature on this therapeutic dilemma and examine the role of endovascular aortic repair (EVAR).

DESIGN, MATERIALS AND METHODS

An observational study of the experience of two centres and a systematic review of the published literature.

RESULTS

Twenty-four patients were identified from the prospective databases of two tertiary referral centres between 2001 and 2006. Intervention for both malignancy and aneurysm was performed in 13 patients. In 10 patients, cancer resection was performed initially and was followed by open aneurysm repair (n=3) or EVAR (n=7). Two patients (AAA diameters: 7.0 and 8.0cm) underwent EVAR prior to colonic resection. One patient was selected for synchronous surgery. There were no interval AAA ruptures, graft infection or postoperative mortalities. Literature review identified 269 such cases; of these 101 were treated by combined surgery. In staged surgery, there were nine interval aneurysmal ruptures and one aortic graft infection.

CONCLUSIONS

In our experience, staged management can be undertaken, without interval aneurysmal rupture. EVAR has an evolving role in preventing delay in CRC management, in high-risk patients, and during combined intervention.

The Neurological Morbidity of Carotid Revascularisation: Using Markers of Cellular Brain Injury to Compare CEA and CAS

AIM

This comparative study attempts to evaluate the profile of S-100beta and Neuron-Specific Enolase (NSE), biomarkers of brain injury, in patients undergoing carotid endarterectomy (CEA) and carotid artery stenting (CAS) and to correlate this with haemodynamic and embolic events detected using trans-cranial Doppler (TCD).

METHODS

52 patients with internal carotid artery stenosis requiring intervention were recruited. 24 patients underwent CAS, and 28 underwent CEA. TCD was performed peri-operatively to record mean Middle Cerebral Artery (MCA) velocity and number of High Intensity Transient Signals (HITS) in the MCA of the operated side. Serum was drawn pre-operatively and at six time points in a 48 hour post-operative period, and then assayed using automated commercial equipment. Within and between group variability in markers were assessed by Generalized Estimation Equations modelling.

RESULTS

CAS caused more HITS (p=0.028) but less haemodynamic disturbance (p=0.0001) than CEA. Treatment modality (CAS versus CEA) had no direct effect on S-100 changes (p=0.467). NSE levels declined after revascularisation in the CAS group but not after CEA (p=0.002). S-100beta levels rose in patients who had higher numbers of HITS (p=0.002). S-100beta and NSE were not associated with changes in MCA velocity (p>0.5). S-100beta alone increased significantly at 24 hours in those patients with a post-operative neurological deficit (p=0.015).

CONCLUSIONS

Trans-cranial Doppler findings suggest that the mechanisms of rise in S-100beta and NSE levels may differ and may be due to increased peri-operative micro-embolisation and cerebral hypoperfusion respectively. Further studies are required to assess the clinical significance of these observed changes.

Identification of Skills Common to Renal and Iliac Endovascular Procedures Performed on a Virtual Reality Simulator

INTRODUCTION

There is a learning curve in the acquisition of endovascular skills for the treatment of vascular disease. Integration of Virtual reality (VR) simulator based training into the educational training curriculum offers a potential solution to overcome this learning curve. However evidence-based training curricula that define which tasks, how often and in which order they should be performed have yet to be developed. The aim of this study was to determine the nature of skills acquisition on the renal and iliac modules of a commercially-available VR simulator.

METHOD

20 surgical trainees without endovascular experience were randomised to complete eight sessions on a VR iliac (group A) or renal (group B) training module. To determine skills transferability across the two procedures, all subjects performed two further VR cases of the other procedure. Performance was recorded by the simulator for parameters such as time taken, contrast fluid usage and stent placement accuracy.

RESULTS

During training, both groups demonstrated statistically significant VR learning curves: group A for procedure time (p<0.001) and stent placement accuracy (p=0.013) group B for procedure time (p<0.001), fluoroscopy time (p=0.003) and volume of contrast fluid used (p<0.001). At crossover, subjects in group B (renal trained) performed to the same level of skill on the simulated iliac task as group A. However, those in group A (iliac trained) had a significantly higher fluoroscopy time (median 118 vs 72 secs, p=0.020) when performing their first simulated renal task than for group B.

CONCLUSION

Novice endovascular surgeons can significantly improve their performance of simulated procedures through repeated practice on VR simulators. Skills transfer between tasks was demonstrated but complex task training, such as selective arterial cannulation in simulators and possibly in the real world appears to involve a separate skill. It is thus suggested that a stepwise and hierarchical training curriculum is developed for acquisition of endovascular skill using VR simulation to supplement training on patients.

A Helical PTFE Arteriovenous Access Graft to Swirl Flow Across the Distal Anastomosis: Results of a Preliminary Clinical Study

Intimal hyperplasia develops preferentially in regions where the blood flow is stagnant and wall shear stress low. The small amplitude helical geometry of the SwirlGraft was designed to ensure physiological-type swirling flow, and thus suppress the triggers. We report the first conceptual testing of the SwirlGraft. Primary, assisted primary and secondary patency rates at 6 months in 20 patients were 57.9+/-11.4%, 84.4+/-8.3% and 100+/-0.0%. There was angiographic evidence of reduction of helical geometry in a proportion of the grafts. The helical graft is associated with high assisted primary and secondary patency. Elaboration of the surgical implantation techniques and an improved SwirlGraft design can be expected to exploit the advantages of the helical concept.

The role of superficial venous operations for leg ulceration

Venous ulceration is a common clinical problem with high recurrence rates. The role of operative treatment to correct superficial reflux in venous ulceration remains unclear. This review reports current evidence for superficial surgical procedures in the treatment of venous ulceration.

Virtual Reality Simulation Training can Improve Inexperienced Surgeons' Endovascular Skills

PURPOSE

The aim of this study was to evaluate virtual reality (VR) simulation for endovascular training of surgeons inexperienced in this technique.

METHODS

Twenty consultant vascular surgeons were divided into those who had performed >50 endovascular procedures (e.g. aortic and carotid stent) as primary operator (n=8), and those having performed <10 procedures (n=12). To test for endovascular skill rather than procedural knowledge, all subjects performed a renal artery balloon angioplasty and stent procedure. The simulator uses real tools with active force feedback, and provides a realistic image of the virtual patient. Surgeons with endovascular skills performed two repetitions and those without completed six repetitions of the same task. The simulator recorded time taken for the procedure, the amount of contrast fluid used and total fluoroscopy time.

RESULTS

Initially, surgeons with endovascular skills were significantly faster (median 571.5 vs. 900.0 s, p=0.039) and used less contrast fluid (19.1 vs. 42.9 ml, p=0.047) than inexperienced operators, though differences for fluoroscopy time were not significant (273 vs. 441 s, p=0.305). Over the six sessions, the inexperienced group made significant improvements in performance for time taken (p=0.007) and contrast fluid usage (p=0.021), achieving similar scores at the end of the training program to the experienced group.

CONCLUSIONS

Surgeons with minimal endovascular experience can improve their time taken and contrast usage during short-phase training on a VR endovascular task. VR simulation may be useful for the early part of the learning curve for surgeons who wish to expand their endovascular interests.

Local and Global Geometric Influence on Steady Flow in Distal Anastomoses of Peripheral Bypass Grafts

We consider the effect of geometrical configuration on the steady flow field of representative geometries from an in vivo anatomical data set of end-to-side distal anastomoses constructed as part of a peripheral bypass graft. Using a geometrical classification technique, we select the anastomoses of three representative patients according to the angle between the graft and proximal host vessels (GPA) and the planarity of the anastomotic configuration. The geometries considered include two surgically tunneled grafts with shallow GPAs which are relatively planar but have different lumen characteristics, one case exhibiting a local restriction at the perianastomotic graft and proximal host whilst the other case has a relatively uniform cross section. The third case is nonplanar and characterized by a wide GPA resulting from the graft being constructed superficially from an in situ vein. In all three models the same peripheral resistance was imposed at the computational outflows of the distal and proximal host vessels and this condition, combined with the effect of the anastomotic geometry, has been observed to reasonably reproduce the in vivo flow split. By analyzing the flow fields we demonstrate how the local and global geometric characteristics influences the distribution of wall shear stress and the steady transport of fluid particles. Specifically, in vessels that have a global geometric characteristic we observe that the wall shear stress depends on large scale geometrical factors, e.g., the curvature and planarity of blood vessels. In contrast, the wall shear stress distribution and local mixing is significantly influenced by morphology and location of restrictions, particular when there is a shallow GPA. A combination of local and global effects are also possible as demonstrated in our third study of an anastomosis with a larger GPA. These relatively simple observations highlight the need to distinguish between local and global geometric influences for a given reconstruction. We further present the geometrical evolution of the anastomoses over a series of follow-up studies and observe how the lumen progresses towards the faster bulk flow of the velocity in the original geometry. This mechanism is consistent with the luminal changes in recirculation regions that experience low wall shear stress. In the shallow GPA anastomoses the proximal part of the native host vessel occludes or stenoses earlier than in the case with wide GPA. A potential contribution to this behavior is suggested by the stronger mixing that characterizes anastomoses with large GPA.

The Relationship Between Plasma MMP-1, -7, -8 and -13 Levels and Embolic Potential During Carotid Endoluminal Intervention

BACKGROUND

Patients undergoing carotid endoluminal intervention are at risk of embolic stroke even with the use of distal protection devices. Matrix metalloproteinases (MMPs) have been implicated as a causal factor in plaque instability leading to spontaneous embolisation. We investigated whether plasma MMP levels correlated with the embolisation during carotid endoluminal intervention.

METHODS

Thirty circumferentially intact carotid endarterectomy specimens were subjected to a standardised angioplasty procedure in a pulsatile ex vivo model. Emboli collected in a series of distal filters were counted and sized. Plasma samples were collected pre-operatively and analysed for MMP-7 and MMP-8 levels using Western immunoblotting. MMP-1 and MMP-13 levels were determined using ELISA. Emboli number and maximum size were correlated with plasma levels of the MMPs using Spearmans rank.

RESULTS

Total MMP-8 levels were related to maximum embolus size (r=0.442, p=0.005) but not emboli number (r=0.342, p=0.052). MMP-1, -7 and -13 were not correlated with either emboli number or with maximum embolus size.

CONCLUSION

Pre-operative plasma MMP-8 levels are related to the size of emboli from plaques during carotid endovascular intervention. Further in vivo studies need to be performed to assess the importance of this finding. There is potential for development of plasma markers to identify those patients at greater risk of embolic stroke during carotid endoluminal intervention.

Phenotypic and functional differences between human saphenous vein (HSVEC) and umbilical vein (HUVEC) endothelial cells

The vascular endothelial cell (EC) plays an essential role in the pathogenesis of inflammation, transplant rejection and tumour metastasis. Most research on vascular ECs uses human umbilical vein endothelial cells (HUVECs). However, HUVECs are derived from immune-naive foetal tissue, and show significant functional differences from adult vascular endothelium. In this paper, we characterise an alternative model based on human saphenous vein ECs (HSVECs), describe their culture conditions and provide a detailed functional comparison with HUVECs. Compared with HUVECs, HSVECs show an increased sensitivity to ox-LDL and a reduced response to cytokines, as indicated by adhesion molecule expression as well as leukocyte adhesion and transmigration. With respect to their ability to present antigen, HSVECs have a higher level of HLA-DR, CD40 and ICOS-L following cytokine stimulation. In addition, HSVECs upregulate the costimulatory ligand CD80 (B7.1) following CD40 ligation, and support allogeneic T cell proliferation, while HUVECs fail to express CD80. Due to differential expression of adhesion molecules, poorly differentiated tumour cell lines also showed more adhesion to HSVECs than to HUVECs. These results indicate that HSVECs have advantages over HUVECs for studying adult vascular endothelial pathology in vitro.

Renal dysfunction and prolonged visceral ischaemia increase mortality rate after suprarenal aneurysm repair

BACKGROUND

Elective juxtarenal abdominal aneurysm repair has a significantly lower mortality rate than suprarenal repair. Identification of factors affecting outcome may lead to a reduction in mortality rate for suprarenal repair.

METHODS

Data were collected prospectively between 1993 and 2000 for 130 patients who underwent type IV thoracoabdominal aneurysm (TAA) repair and 44 patients who had juxtarenal aneurysm (JRA) repair. Preoperative risk factors and operative details were compared between groups and related to outcome after TAA repair (there were only two deaths in the JRA group).

RESULTS

The in-hospital mortality rate was significantly higher following TAA repair (20.0 per cent; 26 of 130 patients) than JRA repair (4.5 per cent; two of 44). Raised serum creatinine concentration was the only preoperative factor (P = 0.013) and visceral ischaemia the only significant operative factor (P = 0.001) that affected mortality after TAA repair.

CONCLUSION

JRA repair was performed with similar risks to those of infrarenal aneurysm repair. Impaired preoperative renal function was related to death following TAA repair and conservative treatment should be considered for patients with a serum creatinine level above 180 micromol/l. Reducing the duration of visceral ischaemia might improve outcome.

Renal disease, age and outcome after aortic aneursym repair

Background

The safety of conventional aneurysm repair is undergoing increased scrutiny as less invasive methods are developed, certain high-risk groups identified and the evidence for the risk of rupture is refined. An understanding of the relationship between preoperative risk factors and outcome is particularly important in elderly patients requiring a prophylactic operation.

Methods

Risk factors (extent of aneurysm, ischaemic heart disease, renal function, hypertension, diabetes, serum cholesterol concentration, age and sex) were studied in 393 consecutive patients undergoing elective juxtarenal and infrarenal aneurysm repair between 1993 and 1999 (inclusive), and were related to hospital mortality.

Results

The overall mortality rate was 5·1 per cent (20 of 393). Multivariate logistic regression analysis revealed that age and creatinine concentration were independent risk factors for in-hospital mortality. Extent of aneurysm was not an independent risk factor, nor was a history of myocardial ischaemia, sex, hypertension, diabetes or serum cholesterol level. The comparative risk related to age and serum creatinine concentration is shown in the Table.

Creatinine level had no influence on outcome in patients aged under 70 years. However, in those over 70 years of age, an increase in creatinine concentration of 10 μmol l−1 increased the relative risk by 0·1 (95 per cent c.i. 0·01–0·18). Increasing age by 10 years increased the relative risk by 1·5 (95 per cent c.i. 0·6–2·4).

Conclusion

Advances in preoperative and perioperative care appear to have reduced the significance of ischaemic heart disease and juxtarenal repair so that age and renal disease are currently major determinants of survival. In aneurysms of less than 7 cm in diameter, where the risk of rupture is less than 10 per cent per year, the natural history of the disease in elderly patients with renal failure appears to be more benign than the treatment.

Improvement in walking ability, ankle pressure indices and quality of life in vascular claudication using intermittent pneumatic foot and calf compression: a randomized controlled trial

Background

Perioperative mortality, graft failure and limitations of balloon angioplasty mitigate against active intervention for claudication. With the exception of exercise programmes, conservative treatments yield modest results. Intermittent pneumatic compression (IPC) of the foot used daily for over 3 months enhances significantly the walking ability and pressure indices of stable claudicants. This prospective randomized study evaluated the effects of IPC of the foot and calf simultaneously (IPCfoot + calf) on the walking ability, arterial haemodynamics and quality of life of patients with intermittent claudication.

Methods

Forty-one stable claudicants, meeting stringent inclusion and exclusion criteria, were randomized to receive either IPCfoot + calf and 75 mg aspirin (group 1; n = 21) or 75 mg aspirin alone (group 2; n = 20), with stratification for diabetes and smoking. Groups matched for age, sex, initial (ICD) and absolute (ACD) claudication distance, ankle: brachial pressure index (ABPI), popliteal artery flow (Q) and quality of life (Short Form (SF) 36 questionnaire). IPCfoot + calf (120 mmHg, three cycles per min, inflation 4 s, proximal inflate delay 1 s) was used for 2·5 h daily for 5 months consecutively. Both groups were advised to exercise unsupervised. Evaluation of patients, after randomization, included: (a) ICD and ACD on a treadmill, (b) resting and postexercise ABPIs, (c) Q using duplex imaging, and (d) quality of life. Study time-points were: baseline and 1, 2, 3, 4, 5 and 17 months. Compliance was assessed by means of a log book. Non-parametric statistical analysis was used (Wilcoxon and Mann–Whitney tests).

Results

After 5 months of IPCfoot + calf median ICD, ACD, resting and postexercise ABPI in group 1 increased by 197, 212, 17 and 64 per cent (all P &lt; 0·001) respectively; changes in group 2 were all non-significant (P &gt; 0·1). On intergroup comparison at 5 months, patients in group 1 were better than those in group 2 in terms of ICD, ACD, resting and postexercise ABPI (all P &lt; 0·01). Q changes within this period were not significant in either group; neither were intergroup Q differences (P &gt; 0·1). Associated changes in the quality of life within group 1 at the end of month 5 were significant; non-significant changes were noted in group 2. At 5 months patients in group 1 enjoyed a better quality of life than those in group 2 (P &lt; 0·01). IPCfoot + calf use did not result in any complications. The daily IPCfoot + calf compliance (2·5 h per day) was greater than 82 per cent in the first month and greater than 85 per cent in months 2–5. One year after the end of IPCfoot + calf application, patients in group 1 maintained the improved ABPI and walking benefit.

Conclusion

IPCfoot + calf emerged as an effective, high-compliance, uncomplicated method for improving the walking ability and pressure indices in patients with stable claudication, with a confirmed durable outcome. These changes are associated with a significant improvement in all aspects of quality of life evaluated by the SF-36. Despite a limited benefit noted in some individuals, unsupervised exercise had a non-significant impact overall.