Femorotibial bypass for claudication: do results justify an aggressive approach?

Distal Bypass Versus Infrageniculate Endovascular Intervention for Chronic Limb-Threatening Ischemia

Chronic limb-threatening ischemia (CLTI) carries a high risk of amputation and warrants urgent intervention. CLTI involving the infrageniculate vessels, in particular, carries a considerably higher risk of major limb amputation. Open surgical bypass is the historical gold standard for the treatment of tibial arterial disease; however, endovascular therapy provides an attractive alternative in this high-risk patient population. In this article, we review the existing literature regarding distal bypass and infrageniculate endovascular intervention in patients with CLTI.

Long-Term Results of Distal Bypass for Intermittent Claudication

BACKGROUND

Distal bypass (DB) is the optimal treatment for patients with critical limb ischemia (CLI). However, effectiveness of DB for patients with intermittent claudication (IC) remains uncertain. This study aimed to analyze long-term results of DB for IC patients (IC-DB) compared with those of DB for CLI patients (CLI-DB).

METHODS

Patients undergoing DB from January 2009 to July 2018 at a single institution were retrospectively reviewed. Operative details, primary and secondary patency, amputation free survival rate (AFS), and long-term exercise capacity using Barthel index were analyzed.

RESULTS

Out of 302 DB (245 patients), 49 IC-DB were performed in 43 patients: 38 males, mean age 70.3 ± 8.0 years, diabetes mellitus 51%, chronic renal failure with hemodialysis 7%. The Great saphenous vein was used in 47 limbs, the small saphenous vein in 1, and the arm vein in 1. These grafts were bypassed in a non-reversed fashion for 35 limbs, in an in-situ fashion in 9, and in a reversed fashion in 5. The mean operative time was 173 min. The mean follow-up was 25 ± 26 months. Primary and secondary patency of IC-DB was 79% and 94% at 1 year, 71% and 90% at 3 years, 65% and 90% at 5 years, which were significantly higher than those of CLI-DB (primary patency: P = .007, secondary patency: P = .025). AFS of IC-DB and CLI-DB was 100% and 77% at 1 year, 93% and 52% at 3 years, and 90% and 43% at 5 years (IC-DB vs. CLI-DB, p < .0001). Barthel index of IC-DB unchanged at discharge (median 100) and at the last visit (median 100), showing daily activity was maintained adequately.

CONCLUSIONS

DB could offer a promising approach for patients with IC because of durable graft patency, acceptable AFS, and maintenance of daily activity.

Tibial bypass in patients with intermittent claudication is associated with poor outcomes

OBJECTIVE

Given that intermittent claudication (IC) rarely progresses to chronic limb-threatening ischemia and limb loss, safety and durability of elective interventions for IC are essential. Whether patients with IC benefit from tibial intervention is controversial, and data supporting its utility are limited. Despite endovascular therapy expansion, surgical bypass is still commonly performed. We sought to assess outcomes of bypass to tibial arteries for IC.

METHODS

The Vascular Quality Initiative (2003-2018) was queried for infrainguinal bypasses performed for IC. Perioperative and 1-year outcomes were compared between bypasses constructed to tibial and popliteal arteries.

RESULTS

Of 5347 infrainguinal bypasses, 1173 (22%) and 4184 (78%) were tibial and popliteal bypasses, respectively. Overall, mean age was 65 ± 10 years, and patients were often men (72%) and current smokers (42%). Tibial bypasses commonly targeted posterior tibial (40%), tibioperoneal trunk (23%), and anterior tibial (19%) arteries. Great saphenous vein was more often used for tibial bypass than for popliteal bypass (78% vs 54%; P < .001). Patients undergoing tibial compared with popliteal bypass more often had impaired ambulation and prior ipsilateral bypasses and were less often taking antiplatelets and statins (all P < .05). In the perioperative period, tibial bypass patients had longer postoperative length of stay (4.5 ± 3.5 vs 3.5 ± 2.8 days), more pulmonary complications (1.3% vs 0.6%), and higher return to the operating room (7% vs 4%; all P < .05). Perioperative myocardial infarction (1.2% vs 0.8%; P = .19), stroke (0.4% vs 0.4%; P = .91), and mortality (0.3 vs 0.3%; P = .86) rates were similar between the cohorts. At 1 year, tibial compared with popliteal bypasses exhibited lower freedom from occlusion/death (81% vs 89%; P < .001), ipsilateral major amputation/death (90% vs 94%; P < .001), and reintervention/amputation/death (73% vs 80%; P < .001), but patient survival was similar (96% vs 97%; P = .07). On multivariable analysis, tibial compared with popliteal bypass was independently associated with increased occlusion/death (hazard ratio [HR], 1.65; 95% confidence interval [CI], 1.28-2.11; P < .001), major ipsilateral amputation/death (HR, 1.6; 95% CI, 1.12-2.19; P = .003), and ipsilateral reintervention/amputation/death (HR, 1.51; 95% CI, 1.28-1.79; P < .001), with similar patient survival.

CONCLUSIONS

In patients with IC, tibial bypass was associated with poor outcomes, including major amputation. Surgeons should exhaust nonoperative therapies and present realistic outcome expectations to their patients before offering such intervention.

Percutaneous versus surgical management of lower extremity peripheral artery disease

Lower extremity peripheral artery disease (PAD) is highly prevalent and can manifest as intermittent claudication or, in the most advanced form, critical limb ischemia. Revascularization, which can be accomplished by an endovascular or surgical approach, is performed to improve quality of life or, in severe cases, for limb salvage. Over the past decade, percutaneous catheter-based techniques have improved such that acute procedural success is high even in complex anatomy. Patency rates have also increased with the use of atherectomy devices and drug-eluting stents. Often, patients with PAD have comorbidities that increase the risk of cardiovascular complications with surgical procedures. These factors have led to the adoption of an endovascular first strategy with surgical management reserved for selected patients. This review focuses on the most current clinical trials of endovascular therapy for PAD. In addition, older but relevant studies comparing endovascular and surgical approaches and contemporary surgical trials are presented for reference.

Society for Vascular Surgery practice guidelines for atherosclerotic occlusive disease of the lower extremities: management of asymptomatic disease and claudication

Peripheral arterial disease (PAD) continues to grow in global prevalence and consumes an increasing amount of resources in the United States health care system. Overall rates of intervention for PAD have been rising steadily in recent years. Changing demographics, evolution of technologies, and an expanding database of outcomes studies are primary forces influencing clinical decision making in PAD. The management of PAD is multidisciplinary, involving primary care physicians and vascular specialists with varying expertise in diagnostic and treatment modalities. PAD represents a broad spectrum of disease from asymptomatic through severe limb ischemia. The Society for Vascular Surgery Lower Extremity Practice Guidelines committee reviewed the evidence supporting clinical care in the treatment of asymptomatic PAD and intermittent claudication (IC). The committee made specific practice recommendations using the GRADE (Grades of Recommendation Assessment, Development and Evaluation) system. There are limited Level I data available for many of the critical questions in the field, demonstrating the urgent need for comparative effectiveness research in PAD. Emphasis is placed on risk factor modification, medical therapies, and broader use of exercise programs to improve cardiovascular health and functional performance. Screening for PAD appears of unproven benefit at present. Revascularization for IC is an appropriate therapy for selected patients with disabling symptoms, after a careful risk-benefit analysis. Treatment should be individualized based on comorbid conditions, degree of functional impairment, and anatomic factors. Invasive treatments for IC should provide predictable functional improvements with reasonable durability. A minimum threshold of a >50% likelihood of sustained efficacy for at least 2 years is suggested as a benchmark. Anatomic patency (freedom from restenosis) is considered a prerequisite for sustained efficacy of revascularization in IC. Endovascular approaches are favored for most candidates with aortoiliac disease and for selected patients with femoropopliteal disease in whom anatomic durability is expected to meet this minimum threshold. Conversely, caution is warranted in the use of interventions for IC in anatomic settings where durability is limited (extensive calcification, small-caliber arteries, diffuse infrainguinal disease, poor runoff). Surgical bypass may be a preferred strategy in good-risk patients with these disease patterns or in those with prior endovascular failures. Common femoral artery disease should be treated surgically, and saphenous vein is the preferred conduit for infrainguinal bypass grafting. Patients who undergo invasive treatments for IC should be monitored regularly in a surveillance program to record subjective improvements, assess risk factors, optimize compliance with cardioprotective medications, and monitor hemodynamic and patency status.

Basic data related to surgical infrainguinal revascularization procedures: a twenty year update

In 1990, Dalman and Taylor published a compilation of reported data that were identified by them as related to infrainguinal revascularization procedures in peripheral vascular surgery during the decade of the 1980s. The intervening 20 years has seen revolutionary advances in the field of peripheral vascular surgery, especially in the adoption of endovascular techniques, and an explosion of data related to emerging technologies in the field of infrainguinal revascularization. The tables in this manuscript reflect the evolution of our surgical knowledge during the turn of the 21st century. The superior patency of autologous saphenous vein in all positions is reaffirmed.

Risk factors for lower-extremity vein graft failure

Lower-extremity vein graft failure causes significant morbidity, increases health care costs, and negatively impacts patient quality of life. Identification of risk factors is essential for patient selection, risk factor modification, and identifying individuals who would benefit from more stringent surveillance protocols. Risk factors can be considered as either patient-related or technical. Here we discuss the patient-related risk factors for vein graft failure. Nontechnical factors related to the indication for operation include operation after a previously failed graft, or redo bypass, critical limb ischemia, and infection. Risk factors for vein graft failure are distinct from the risk factors for cardiovascular events. Young age and African American and Hispanic race are risk factors for lower-extremity vein graft failure. Hypercoaguable and inflammatory states also increase risk for vein graft failure. Therapy with statins is indicated in patients with peripheral atherosclerosis and may have beneficial effects on vein graft function, although further studies are needed in this area.

Defining the potential for cell therapy for vascular disease using animal models

Cell-based therapeutics are currently being developed for a wide array of unmet medical needs. As obstructive vascular disease is the major cause of mortality in the world, cell-based strategies aimed at developing novel therapies or improving current therapies are currently under study. These studies are based on the evolving understanding of the biology of vascular progenitor cells, which has in turn led to the availability of well-defined sources of vascular cells for delivery. Crucial to the development of these approaches is the preclinical testing of cell delivery in animal models. This review highlights the crucial steps involved in the selection of cell sources and generation, delivery approaches, animal models to be used, and endpoints to be studied, in the context of cell delivery for vascular disease. Furthermore, the development of cell delivery to induce angiogenesis in ischemic limbs and to improve the response to large vessel injury will be discussed.

Lesion severity and treatment complexity are associated with outcome after percutaneous infra-inguinal intervention

OBJECTIVES

Percutaneous revascularization has become increasingly utilized for the treatment of lower extremity ischemia. Patients with limb-threat have been shown to be at increased risk of failure, although the reasons for this remain unclear. This study analyzed factors associated with percutaneous treatment failure, focusing specifically on lesion characteristics and treatment complexity.

METHODS

We retrospectively reviewed percutaneous infra-inguinal interventions performed for peripheral occlusive disease between 2002 and 2005 using a prospectively maintained database. Lesion characteristics were assessed by angiography, and lesions were graded according to the TransAtlantic InterSociety Consensus (TASC) criteria. Patency was expressed by Kaplan-Meier method and compared by log-rank analysis. Multivariate Cox-regression analysis was used to assess significant factors on univariate analysis. Mean follow-up was 11.8 months.

RESULTS

A total of 324 interventions for claudication (55.8%), rest pain (18.4%), or tissue loss (25.8%) were analyzed, including 284 primary interventions and 40 re-interventions in 258 patients (mean age 72.1 +/- 10 years, 51.0% male). TASC lesion grades included: A (4.9%), B (29.3%), C (37.7%), and D (28.1%). Isolated single-level interventions (femoral, popliteal, or tibial) were performed in 38.9%, while two-level interventions were performed in 46.2% and three-level interventions in 14.9%. Overall primary patency (+/- SD) at 6, 12, and 18 months was 87 +/- 2%, 66 +/- 2% and 59 +/- 4%, respectively. Secondary patency at 6, 12, and 18 months was 89 +/- 2%, 76 +/- 3%, and 69 +/- 5%. One-year limb salvage rate (limb-threat patients) was 85 +/- 3%. Limb-threatening ischemia as the indication for intervention was most highly associated with failure of both primary and secondary patency and was associated with four indicators of lesion severity and treatment complexity, including increasing TASC grade, multilevel intervention, tibial intervention, and reduced tibial outflow. One-year primary patency was inversely correlated with TASC severity (TASC A-C: 67 +/- 6%, D: 61 +/- 4%; P < .05), multilevel intervention (76 +/- 5% and 49 +/- 9% for single vs multilevel, P = .002), distal interventions (74 +/- 5% and 57 +/- 7% for femoral vs tibial, P < .05), and decreased tibial runoff (83 +/- 6% and 52 +/- 6% for three- vs < three-vessels, P < .02). No differences in secondary patency or limb-salvage rates existed for these lesion- and treatment-related variables. Multilevel intervention and tibial intervention remained significant independently associated with primary patency on multivariate analysis.

CONCLUSIONS

Patients with limb-threatening ischemia are at increased risk of initial failure compared with claudicants, likely as a result of the increased prevalence of advanced lesion severity and treatment complexity, which are associated with decreased primary patency. However, this finding did not extend to secondary patency or limb-salvage in the overall patient population. Although additional studies with longer follow-up are needed, these findings argue that percutaneous intervention may still be considered as a primary treatment modality with the understanding that these patients may have higher re-intervention rates and may ultimately require salvage open surgical bypass for persistent failures of percutaneous therapy.

Infrapopliteal Intervention for the Treatment of the Claudicant

As the associated risks of infrainguinal balloon angioplasty and stenting have fallen and the relative success rates have risen in recent years, the threshold for offering endovascular treatment to patients with claudication has significantly decreased. Patients once considered appropriate only for risk-factor modification, exercise therapy, and medical treatment are now increasingly being offered percutaneous revascularization as a primary treatment option. Similarly, occlusive disease of the tibial vessels, once thought to be the exclusive domain of operative bypass, is increasingly being treated percutaneously. Over this same period, results of operative infrainguinal arterial reconstruction have also considerably improved. In modern times, excellent outcomes following bypass grafting with autogenous vein to the tibial level have been demonstrated, with morbidity, mortality, and long-term patency equivalent to that of more proximal bypasses. Evidence supports the view that the anatomic level of the distal anastomosis is less critical to the long-term outcome of the procedure than factors such as operative indication and conduit quality. Within the context of this changing climate, it is an appropriate time to examine and potentially redefine the role of both endovascular and open surgical intervention for a population that has not traditionally been offered revascularization, patients with claudication secondary to infrageniculate occlusive disease.

Therapeutic uses of autologous endothelial cells for vascular disease

Endothelial cells play important structural and functional roles in vascular homoeostasis. Perturbations in endothelial cell number and function are directly involved with the initiation and progression of multiple cardiovascular diseases, including atherosclerosis, hypertension and congestive heart failure. Attempts to modify these disorders have included pharmacological strategies to improve vascular and thus endothelial function. A goal of biological approaches to these disorders is the delivery of endothelial cells that might act to provide beneficial endothelial-derived factors. However, this approach has generally been limited by the lack of readily available autologous endothelial cells for delivery. The isolation of circulation-derived endothelial progenitor cells allows for direct access to autologous endothelial cells for preclinical and clinical studies. Preclinical studies using autologous endothelial cells have demonstrated beneficial effects when delivered in animal models of vascular injury and grafting. These effects are related to the endothelial nature of the cells and may be paracrine in nature. Ongoing studies are aimed at defining the nature of these effects and optimizing delivery strategies cognizant of these mechanisms.

Natural history of stenosis in the iliac arteries in patients with intermittent claudication undergoing clinical treatment

PURPOSE

Inspite of the long experience with the treatment of intermittent claudication, little is known about the natural history of stenotic lesions in the iliac segment. With the advent of endovascular treatment, this knowledge has become important.

METHODS

Fifty-two stenosis, diagnosed using arteriography, in 38 claudicant patients were analyzed. After a minimum time interval of 6 months, a magnetic resonance angiography was performed to determine whether there was arterial occlusion. The primary factors that could influence the progression of a stenosis were analyzed, such as risk factors (smoking, hypertension, diabetes, sex, and age), compliance with clinical treatment, initial degree of stenosis, site of the stenosis, and length of follow-up.

RESULTS

The average length of follow-up was 39 months. From the 52 lesions analyzed, 13 (25%) evolved to occlusion. When occlusion occurred, there was clinical deterioration in 63.2% of cases. This association was statistically significant (P = .002). There was no statistically significant association of the progression of the lesion with the degree or site of stenosis, compliance with treatment, or length of follow-up. Patients who evolved to occlusion were younger (P = .02). The logistic regression model showed that the determinant factors for clinical deterioration were arterial occlusion and noncompliance with clinical treatment.

CONCLUSIONS

The progression of a stenosis to occlusion, which occurred in 25% of the cases, caused clinical deterioration. Clinical treatment was important, but it did not forestall the arterial occlusion. Prevention of occlusion could be achieved by early endovascular intervention or with the development of drugs that might stabilize the atherosclerotic plaque.

Peroneal artery reconstruction via medial approach using tourniquet occlusion

As peroneal artery bypass surgery is technically demanding, a simplified medial approach was used in 23 peroneal artery reconstructions in 21 patients between January 1993 and December 2001. The outcomes were reviewed retrospectively. Peroneal artery reconstruction was undertaken through a medial skin incision using tourniquet occlusion and saphenous vein grafts. Graft patency was confirmed by angiography or duplex color imaging. Peroneal bypass was possible through the medial approach in 20 cases; in 1 limb, the target was occluded. During a mean follow-up of 43.9 months, there were 4 graft occlusions. None of the failures was due to a technical error related to the procedure. All of the other patients had relief of their symptoms, including those who presented with disabling claudication. Technical improvements have made peroneal bypass a reasonable choice in below-knee arterial reconstruction. This technique should not be restricted to limb salvage.

Comparison of the long-term results between surgical and conservative treatment in patients with intermittent claudication

BACKGROUND

The optional therapeutic strategy for patients with intermittent claudication remains controversial. In this study, we investigated the influence of surgical and conservative therapies on improving the quality of life in patients with intermittent claudication.

METHODS

We analyzed 427 patients who were admitted to our hospital with intermittent claudication in their legs during a 15-year period from January 1984 to December 1999. We separated them into 2 groups; 259 patients (362 legs) were treated surgically and 168 patients were treated conservatively.

RESULTS

At the suprainguinal and infrainguinal (above knee) region, the surgery group showed significantly better rate of improvement than did the conservative group, but in the infrainguinal (below knee) region, there was no significant difference between the 2 groups. The 3-year and 5-year patency rates for the arterial reconstruction of the suprainguinal and infrainguinal region was satisfactory, but that of the infrainguinal region was not very good even if an auto vein graft was used.

CONCLUSIONS

Aggressive surgical treatment is therefore recommended in patients whose distal anastomotic region is above the knee, because there are great benefits from surgical reconstruction. However, in patients whose distal anastomotic region is below the knee, conservative treatment might be just as effective as surgery.

Endovascular and surgical revascularization for patients with intermittent claudication

Intermittent claudication (IC), the most common symptom of peripheral arterial disease (PAD), most often results from flow-reducing lesions in the arteries of the lower extremity that cause exercise-induced muscle ischemia. Intermittent claudication has a significant impact on quality of life and calls attention to PAD, which is secondary to systemic atherosclerosis and a major marker for cardiovascular morbidity and mortality. Most IC patients improve with a regimen that includes aggressive risk-factor modification, exercise, platelet inhibition, and pharmacotherapy to improve walking distance. Selected patients may require endovascular or surgical intervention if it can be offered with low risk. Endovascular procedures, most often percutaneous balloon angioplasty with or without stenting, are recommended for short-segment stenotic lesions in the aortoiliac and infrainguinal arterial segments. Combined platelet inhibition and endoluminal radiation are under study and may be useful to improve long-term outcome with these procedures. Percutaneous hemostatic puncture closure devices can also be used to reduce bleeding complications and allow more aggressive and immediate antithrombotic therapy, further improving results. Operative revascularization is recommended for patients with long-segment and multisegment disease, especially if obstruction is present. Aortofemoral reconstruction is associated with a low operative mortality and an 80% to 85% 5-year patency rate. Iliac reconstruction is recommended for isolated unilateral iliac arterial disease. Infrainguinal arterial reconstruction is associated with a 60% to 80% 5-year patency rate, with better outcomes noted for autogenous conduits than for prosthetic devices. Mechanical modification and pharmacotherapy with platelet inhibitors and anticoagulants improve long-term patency.

Use of arteriography for the initial evaluation of patients with intermittent lower limb claudication

CONTEXT

Many patients with intermittent claudication continue to be forwarded to the vascular surgeon for initial evaluation after arteriography has already been accomplished.

OBJECTIVE

The main objective of this work was to analyze the usefulness and the need for this procedure.

TYPE OF STUDY

Retrospective study.

SETTING

The patients were divided into two groups: Group 1, with the arteriography already performed and Group 2 without the initial arteriography.

PARTICIPANTS

One hundred patients with intermittent claudication were retrospectively studied. Other specialists had forwarded them for the first evaluation of intermittent claudication, without any previous treatment.

MAIN MEASUREMENTS

All patients were treated clinically for at least a 6-month period. The total number of arteriographies performed in the two groups was compared and the need and usefulness of the initial arteriography (of Group 1) was also analyzed.

RESULTS

The evolution was similar for both groups. The total number of arteriographies was significantly higher in Group 1 (Group 1 with 53 arteriographies vs. Group 2 with 7 arteriographies). For this group, it was found that arteriography was only useful in five cases (10%), because the surgeries were based on their findings. However, even in those cases, no need for arteriography was observed, as the procedure could have been performed at the time of surgical indication.

CONCLUSION

There are no indications for arteriography in the early evaluation of patients with intermittent claudication, because it does not modify the initial therapy, independent of its result. In cases where surgical treatment is indicated, this procedure should only be performed prior to surgery.

Infrainguinal arterial reconstruction for claudication: is it worth the risk? An analysis of 409 procedures

PURPOSE

Infrainguinal reconstruction traditionally has been reserved for patients with limb-threatening ischemia. Surgery for debilitating claudication, however, has been discouraged as a result of the perceived fear of bypass graft failure, limb loss, and significant perioperative complications that may be worse than the natural history of the disease. In this study, the results of infrainguinal reconstructions for claudication performed during the past 10 years were evaluated for bypass graft patency, limb loss, and long-term survival rates.

METHODS

Data were collected and reviewed from the vascular registry, the office charts, and the hospital records for patients who underwent infrainguinal bypass grafting for claudication.

RESULTS

From 1987 to 1997, 409 infrainguinal reconstructions were performed for claudication (9% of all infrainguinal reconstructions in our unit). The patient population had the following demographics: 73% men, 28% with diabetes, 54% smokers, and an average age of 64 years (range, 24 to 91 years). Inflow was from the following arteries: iliac artery/graft, 10%; common femoral artery, 52%; superficial femoral artery, 19%; profunda femoris artery, 16%; and popliteal artery, 2%. The outflow vessels were the following arteries: 165 above-knee popliteal arteries (40%), 150 below-knee popliteal arteries (37%), and 94 tibial vessels (23%). The operative mortality rate was 0%, and one limb was lost in the series from distal embolization. The primary patency rates were 62%, 77%, and 86% for above-knee popliteal artery, below-knee popliteal artery, and tibial vessel reconstructions at 4 years, and the secondary patency rates were 64%, 81%, and 90%, respectively. Cumulative patient survival rates were 93% and 80% at 4 and 6 years as compared with 65% and 52%, respectively, for infrainguinal reconstructions performed for limb salvage.

CONCLUSION

Infrainguinal arterial reconstruction for disabling claudication is a safe and durable procedure in selected patients. These data indicate that concern for limb loss, death, and limited life span of the patients with this disease may not be warranted.

Vascular morbidity and mortality during long-term follow-up in claudicants selected for peripheral bypass surgery

OBJECTIVES

To identify claudicants at high risk (and low risk) of late vascular morbidity and mortality after peripheral bypass surgery.

DESIGN

Prospective cohort study with mean follow-up of 8.6 years.

PATIENTS

One-hundred and fifty-five claudicants selected for peripheral bypass surgery. Only three patients were lost to follow-up. End points were major vascular events, additional interventions, all-cause mortality, and functional outcome.

RESULTS

Major vascular events occurred in 59 patients. Life-table analysis revealed an annual risk increase of 3.5%. Strong predictors were hypertension (hazard ratio (HR) 2.7; 95% confidence interval (CI) 1.5-4.8), diabetes (HR 2.4; 95% CI 1.0-5.4) and cardiac disease (HR 2.2; 95% CI 1.2-4.0). Sixty patients needed additional interventions with a highest incidence (17%) in the first year, and thereafter 2.8% each year. None of the known risk factors were associated with an altered incidence of interventions. Approximately 3.5% of patients died per year compared with 2% per year in the control group. Prominent high-risk factors for mortality were cardiac disease (HR 3.3; 95% CI 1.8-6.0) and diabetes (HR 3.0; 95% CI 1.5-7.1).

CONCLUSION

Major vascular events and additional interventions are common and serious in claudicants. However, it is possible to select low-risk patients in which peripheral bypass surgery is justified.

Reduction of hospital resources utilization in vascular surgery: a four-year experience

PURPOSE

Managed care whether through risk or through capitated contracts results in reduction in resources, reduced length of hospital stay, and reduced utilization of hospital resources (collectively referred to as resource reductions). These resource reductions will become even more noticeable as a greater proportion of Medicare patients who need vascular operations select a managed-care senior product. We examined the results of a 4-year experience with resource management in an academic vascular surgery practice during which best practice plans were developed and implemented.

METHODS

We analyzed hospital cost data, which included both total hospital and intensive care unit length of stay, average units per operation for laboratory, pharmacy, and radiology services and operating room and direct hospital costs for 257 carotid endarterectomies performed over fiscal years (FY) 1994, 1995, 1996, and 1997 (6 month data) and 175 infrainguinal bypass procedures performed during the same period.

RESULTS

For carotid endarterectomy, length of stay decreased 66% over the 4-year period to an average of 2.07 days in FY97. Both radiology and pharmacy utilization were reduced after the first year of institution of best practice plans (56% and 32% respectively) with 4-year total reductions of 86% and 55% by FY97. The most notable changes included elimination of routine postoperative laboratory testing, use of aspirin rather than low-molecular-weight dextran, emphasis on oral rather than intravenous vasoactive drugs, and routine use of duplex scanning alone rather than angiography for diagnosis after FY94-95. The length of operating room time for carotid endarterectomy remained relatively constant from FY94 to FY97. As a result of these multiple factors, our study showed a 30% decrease in total average direct hospital costs for carotid endarterectomy from $9974 to $7002 in this 4-year period. Infrainguinal bypass graft procedures showed a progressive decrease in total cost of 28% for patients without complications to $15,186 but remained unchanged for those with complications. Laboratory use, pharmacy use, and radiology use were not significantly different.

CONCLUSIONS

Case management for patients undergoing carotid endarterectomy and infrainguinal bypass grafting involving an integrated team of vascular surgeons, surgical house staff, a dedicated vascular nurse, and a social work case manager resulted in dramatic reductions both in length of stay and hospital resource utilization. As these costs decreased, operating room expenses assumed increasing importance. Operating room costs account for 60% of the direct costs of carotid endarterectomy and a comparable percentage for uncomplicated infrainguinal bypass grafting. Further substantial reductions in direct hospital costs will depend primarily on reductions in operating room costs, particularly those related to length of time in the operating room.

Exercise therapy for intermittent claudication: a review of the quality of randomised clinical trials and evaluation of predictive factors

OBJECTIVE

To establish the effect of exercise therapy in patients with intermittent claudication and to identify outcome predictors for exercise training.

DESIGN

A methodological study of randomised clinical trials.

METHODS

A quality assessment of all eligible studies was performed, using a list of methodological criteria. A weighing scale for the criteria was developed, based on four main categories: study population, intervention, outcome variables and data presentation/analysis.

RESULTS

Ten studies were included in the analysis. Seven randomised clinical trials had a methodological score of 60 or more points (maximum 100), and were considered to be of good quality. The mean of the methodological score was 62.5 (S.D. 8.5). Improvement in pain-free/maximum walking distance/time ranged from 28-210% (mean 105, S.D. 55.8). Only one study evaluated outcome predictors for exercise therapy.

CONCLUSIONS

All studies reported a positive effect of exercise therapy on walking distance in patients with intermittent claudication, but no predictive factors were clearly identified. Future research efforts should focus on improving the quality of clinical research for patients with intermittent claudication and developing optimal rehabilitation programs.

A paper for debate: vein versus PTFE for critical limb ischaemia--an unfair comparison?

INTRODUCTION

There is a widely held view that vein grafts for infrainguinal arterial reconstruction perform much better than prosthetic conduits, the best of which seems to be PTFE. Many randomised studies have been conducted which confirm this opinion, but is the difference as large as it is thought to be? One interesting feature of published trials is that the results for obligatory PTFE (when no vein is available) were much worse than the results for randomised PTFE grafts. The only way to explain this is that these groups of patients were not similar, and there are probably other factors which contribute to the difference in results when vein and PTFE grafts are compared.

MATERIALS AND METHODS

A consecutive series of 109 femoro-infrapopliteal grafts undertaken for critical limb ischaemia was analysed to see the difference between vein and PTFE with vein cuff grafts.

RESULTS

Vein grafts were superior to PTFE grafts when the whole cohort was included (p = 0.0038); however, there was no significant difference when the patients were stratified for inflow and runoff status.

CONCLUSIONS

The difference between vein and PTFE has probably been exaggerated in the past, due to differences in risk factors and in the extent of arterial disease between the two groups of patients. The advantage of vein becomes more significant with time.

Functional outcome after surgical treatment for intermittent claudication

PURPOSE

Although patency data for lower extremity bypass grafts are readily available, few reports have focused on patients' satisfaction after surgical reconstruction for claudication. We reviewed our experience with surgical treatment for claudication, focusing on late outcome from the patients' perspective to further refine surgical decision making in patients with intermittent claudication.

PATIENTS AND METHODS

From February 1987 through April 1994, 114 consecutive patients underwent surgical bypass for intermittent claudication. Nine patients were lost to follow-up, leaving the study cohort composed of 105 patients with a mean age of 63 years (range 42 to 82 years). Sixty-two percent of the procedures were inflow reconstructions, and the remainder were infrainguinal bypasses. Clinical and demographic data were gathered from record review, and late follow-up was obtained by return visit or telephone interview. Patient satisfaction and level of function were assessed by a simple five-point questionnaire administered by a research nurse. Actuarial methods were used to calculate late graft patency and survival. Cox regression analysis was used to identify clinical and anatomic factors predictive of late survival and favorable outcome.

RESULTS

Cardiac risk assessment revealed that 75% of patients either had no clinical markers for cardiac disease or had been treated with previous coronary artery bypass grafting or percutaneous transluminal angioplasty; despite this 61% of patients underwent specific preoperative cardiac testing. Most (68%) inflow procedures were aortobifemoral bypass grafts, and 93% of outflow procedures were femoropopliteal bypass grafts. Two thirds of infrainguinal grafts were performed with autogenous conduits, with prosthetic femoropopliteal bypass grafts performed only to the above-knee popliteal artery. Early graft failure with successful immediate revision occurred in 5% of patients. No operative deaths or early or late amputations occurred. At a mean follow-up of 4.5 years 96% of surviving patients had a patent graft. However, primary unassisted patency at 4 years was superior for inflow (92% +/- 4%) versus outflow (81% +/- 6%) procedures (p = 0.009). Late readmission for cardiac-related events occurred in 12%, and late cardiac-related death occurred in 5%. Actuarial survival at 5 years was 80% +/- 5%, with diabetes being the only negative survival predictor (risk ratio 2.6, 95% confidence interval 1 to 7, p = 0.049); 60% of late deaths were cancer-related. Satisfactory late results were reported by 82% of patients, with age < or = 70 years (odds ratio 4.01, 95% confidence interval 1.2 to 13.7, p = 0.026) and normalization ( > or = 0.85) of ankle/brachial index (odds ratio 5.7, 95% confidence interval 1.6 to 20, p = 0.008) being powerful independent predictors of patient satisfaction.

CONCLUSIONS

After considering cardiac-related short- and long-term prognosis, we conclude that lower extremity bypass grafting for intermittent claudication will produce optimal results when restricted to younger ( < 70 years) nondiabetic patients in whom near normalization of the postoperative ankle/brachial index can be anticipated.