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We present a case in which endovascular stenting was used for recurrent proximal para-anastomotic stenosis 11 years after aorto-bi-iliac bypass grafting for severe aorto-iliac occlusive disease. A 55-year-old woman presented with worsening bilateral hip and buttock claudication. At presentation, her resting ankle-brachial indices were 0.87 bilaterally and decreased to 0.39 on the right and 0.40 on the left with exercise. Aortography demonstrated a proximal para-anastomotic aortic graft stenosis without distal outflow obstruction, patent superficial femoral arteries, and good triple-vessel runoff bilaterally The stenosis was dilated with a 9- x 4-cm OPTA balloon angioplasty catheter. A Palmaz stent (P424, Cordis) was mounted on a 10- x 4-cm OPTA balloon catheter and deployed across the proximal stenosis. Completion arteriography confirmed adequate placement and reduction in the degree of stenosis. There was no pressure gradient across the proximal anastomosis. At our patient's 1-week follow-up visit, her resting ankle-brachial indices were both greater than 1.0 and her exercise ankle-brachial indices were 1.0 bilaterally She remained asymptomatic at 13 months. Most late sequelae of aortic graft surgery involve the distal anastomosis and are resolved surgically without complicated techniques. However, revision at the proximal anastomosis involves the aorta directly and therefore requires open abdominal dissection and aortic cross-clamping. Percutaneous aortic stenting for primary aortoiliac disease has been shown to reduce operative time, cost, and hospital stays, to improve patency and to be durable. Our clinical experience with aortic stenting for primary disease led us to consider this procedure for recurrent proximal stenosis.

The exclusion of abdominal aortic aneurysms with endoluminal grafts has generated a great deal of interest since the early 1990s, and many centers are currently evaluating the procedure and comparing it to classic surgical exclusion. Although endoluminal grafting procedures show promise, development and clinical testing of devices is a time-consuming process that is influenced greatly by the regulatory climate in the country where the clinical trials take place. Nevertheless, a number of devices are currently under study, and the advantages of 2nd- and 3rd-generation technology are reflected in reduced rates of complications such as endoleaks and thrombosis. Further study will be required to perfect these devices and observe their long-term success in the exclusion of abdominal aortic aneurysms.

Technological advances in endoluminal equipment have changed treatment strategies for vascular disease. While the successful results of intervention in the subclavian and innominate arteries are well documented, our experience in the carotid arterial region is still in the early stages, and we are mindful of the potential for neurologic complications. We now find ourselves in the position of comparing the results of endovascular intervention with those of what has become a classic, "gold standard" procedure, carotid endarterectomy. Although we have yet to determine definitively the superiority of one method over another, it has become clear that some carotid lesions are considerably more amenable to endovascular treatment than others. We must evaluate the type and location of lesions, as well as the technical features of carotid angioplasty and stent placement, when we compare the results of endovascular and open procedures.

Treatment of iliac artery disease with stents has been generally successful; however, disease in the smaller arteries below the inguinal ligament has been more resistant to percutaneous intervention techniques. Ongoing research is evaluating the potential value of newer, more flexible stents as well as the use of covered endoluminal grafts to "reline" diseased arterial segments. It is possible that intimal hyperplasia may be reduced by covering the stent on one or both sides with a fabric such as polytetrafluoroethylene, yielding improvements in long-term patency. A number of device manufacturers have developed Investigational Device Exemption protocols with the Food and Drug Administration to allow randomized comparison of covered grafts and uncovered stents. The use of endoluminal grafts in the treatment of large aneurysms involving the common and internal iliac arteries and the origin of the external iliac artery is also under investigation; this application may prove advantageous, since operative intervention in these locations is often difficult. In addition, the endoluminal graft has been used to manage traumatic or iatrogenic rupture of an iliac artery, and the use of systems incorporating nitinol stents for an "internal" femoropopliteal bypass procedure is also being studied. Although aneurysmal disease in the superficial femoral artery is uncommon, the use of endoluminal grafts now makes it possible to treat these lesions percutaneously with an intraluminal approach; endoluminal graft exclusion of aneurysmal disease in the popliteal artery is also promising.

We report the results of stenting in 17 patients who underwent treatment for total occlusions in the subclavian arteries between July 1991 and December 1995. Fourteen of the lesions were located in the left side; 15 patients had a subclavian steal syndrome. The indications for treatment were vertebrobasilar insufficiency (n = 7); arm claudication (n = 5); vertebrobasilar insufficiency and upper-limb ischemia (n = 3); protection of a left internal mammary artery coronary bypass (n = 1); and an isolated subclavian steal syndrome (n = 1). A total of 23 stents were implanted in 17 patients; in 1 patient, 2 stents migrated during deployment, resulting in a 94% procedural success rate. One case of axillary thrombosis was successfully treated with local thrombolysis and balloon angioplasty. There were no postprocedural neurologic complications or deaths. Follow-up over a mean duration of 19.4 months (range, 4 to 56 months) revealed 1 asymptomatic restenosis at 5 months in a patient with 3 stents. Life-table analysis showed an 81% cumulative patency rate at 6 months. We conclude that stenting for occlusion of the subclavian arteries appears feasible and safe; however, further evaluation in a larger group of patients is needed to confirm these results.

We report the long-term results of abdominal aortic stenting in 24 patients who underwent stenting for atherosclerotic occlusive disease (16 stenoses, 6 occlusions, and 2 ulcerative plaques). The occlusions were treated initially with thrombolytic therapy, and all lesions were balloon dilated. Indications for stenting were: residual gradient (n = 10); recoil (n = 7); dissection (n = 2); and atherosclerotic debris (n = 5). Thirty-eight Palmaz stents were implanted in the aorta, and 21 were implanted in the common iliac (n = 19) and external iliac (n = 2) arteries. Technical and clinical success was 100%. Over a mean follow-up period of 48 months (range, 1 to 67 months), 2 patients died and 2 were lost to follow-up. Two patients developed symptoms referable to the aorta (at 43 and 67 months), and each was managed successfully via an endovascular approach. There was no in-stent restenosis. Life-table analysis showed a 100% cumulative primary patency at 5 years. We conclude that stenting for abdominal aortic occlusive disease appears to offer long-term patency slightly superior to that of classical surgical intervention. Aortic stents also do not appear to be subject to restenosis. Follow-up in a larger patient cohort is needed to confirm these observations.

The exclusion of abdominal aortic aneurysms with endoluminal grafts is in its earliest stages, and the technology is in continuous transition. While results with 1st-generation devices have been somewhat discouraging in some cases, lessons learned from these initial attempts have led to considerable improvement in device design and deployment techniques. Lower-profile devices that are smaller and more flexible have made implantation less traumatic, and the incidence of endoleak formation has been reduced to 10% or less in some series. A modified percutaneous approach has also been introduced, and it may reduce the need for open exposure of the femoral artery in endoluminal graft procedures. Treating aneurysm expansion earlier, perhaps at 4 cm, may allow use of simpler, straight-tube prostheses and prevent problems associated with the use of larger, bifurcated endoluminal grafts. Numerous endoluminal graft designs are being tested, including both internally and externally covered prostheses. The success with a covered device may depend upon the type of material used and the extent to which it covers the endoluminal graft; fabric covering over a completely metal structure may allow a high degree of perioperative success and improvement in late outcome. The use of "hooks" to anchor or stabilize the endoluminal graft is also under study but is still controversial. The expense associated with endoluminal graft technology is currently high; therefore, it is likely that cost savings will be the result of shorter hospitalizations, little or no time spent in the intensive care unit, and fewer pre- and postoperative tests.

Although laser-assisted angioplasty is becoming increasingly common, there has been no definitive report, drawing its data from a significant patient population, regarding the complications of this technique. To define and enumerate such adverse results, we collected data on 664 peripheral laser procedures performed in 349 patients over a 15-month period (February 1987 through April 1988). The complications proved similar to those of standard angioplasty: hematoma formation, 100 cases (15.0%); perforation/dissection, 38 cases (5.7%); acute thrombosis, 23 cases (3.5%); false aneurysm formation at the puncture site, 7 cases (1.1%); vascular spasm, 5 cases (0.8%); and embolism, 1 case (0.2%). Because perforation was the most significant complication during angioplasty, we devised a system for uniform documentation and reporting of perforations, based on both the arterial condition responsible for the laser probe's deviation and the clinical consequences of the aberration. According to this system, Class-I perforations are dissections that do not penetrate the adventitia; Class-II perforations are adventitial wall ruptures (true perforations) that do not require treatment; and Class-III perforations are adventitial wall ruptures with hemorrhage. In our series, we had no Class-III perforation, but had 21 Class-I (3.1%) and 17 Class-II (2.6%) perforations. Because prudent treatment of an evolving complication often can salvage the procedure, we discuss appropriate therapies, as well as preventive measures.