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In his presidential address to the American Association for Vascular Surgery in 2000, the late Dr. John Porter announced that there was insufficient time in the vascular training program to entertain endovascular technology because of the volume of vascular surgery techniques that must be learned. His philosophy accurately depicted the prevailing attitude of vascular surgical academia until very recently, and this restrictive stance has caused gradual but profound diminution in the caseload of vascular surgeons who are not trained in endovascular surgery techniques. Ultimately, the reluctance of vascular surgeons to expand their skill sets to include expertise in percutaneous interventions has enhanced the two competing disciplines of cardiology and radiology. As an early proponent of exploring endovascular therapy and its attendant tools and devices, my personal experience--both favorable and unfavorable--has provided me with a degree of perspective about the current status of endovascular surgery and enough background to speculate about the future role of the vascular surgeon in the treatment of arterial and venous disease. Parenthetically, it is encouraging that over the last few years, many educators in the field of vascular surgery have adopted a much more enlightened viewpoint regarding endovascular procedures. Hopefully, the pendulum has not already swung too far out of balance, and vascular surgeons will still have the opportunity to participate fully in the future of this exciting endovascular field. The following observations, ideas, and suggestions may pertain more to young trainees about to enter practice than to seasoned vascular surgeons.

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.

Purpose: To examine the long-term outcome of patients treated with endoluminal grafts (ELGs) for aneurysmal and occlusive disease in the femoropopliteal (FP) segment., Methods: ELGs of radially expandable polytetrafluoroethylene with terminal Palmaz stents were used to form intimal conduits to revascularize lengthy occlusive disease and exclude aneurysms in the FP segment. Patient records were reviewed retrospectively for outcome., Results: Fifty-five (98%) of 56 ELGs were placed successfully in 51 patients treated from August 1993 to February 1996. Over a mean 36-month follow-up, 28 (50%) ELGs occluded. Half of these failures reflected early technical difficulties. There were 11 (20%) stent stenoses, 6 in the proximal stent and 5 in the distal device. The majority of the graft failures were treated with endovascular techniques; however, FP bypass was required in 7 (25%) patients, while 2 (7%) were not treated. Life-table analysis demonstrated 46% primary and 68% secondary patency rates at 24 months. Among demographic and procedural variables, only previous dilation or stent procedures in the target artery was associated with failure (p < 0.0001)., Conclusions: The prototype ELG used in this series demonstrated durability similar to conventional surgical therapy utilizing synthetic material. Endoluminal grafting of FP lesions may be a more durable alternative to classical bypass once devices and techniques are refined.

Background: We examine the technique of combining percutaneous transluminal angioplasty and secondary intravascular stent deployment with femorofemoral bypass graft in patients with bilateral aortoiliac occlusive disease., Study Design: Retrospective review., Results: During the 5-year period from June 1988 to October 1993, 18 patients with iliac occlusion and a hemodynamically significant contralateral iliac stenosis were treated using a combination of endovascular and open surgical techniques. Patients (13 men and 5 women) ranged in age from 50 to 78 years (mean, 64 years). Thirteen patients (72 percent) were treated for claudication, and 5 patients (28 percent) for rest pain or ulceration. Residual intra-arterial pressure gradients following percutaneous transluminal angioplasty or significant postpercutaneous transluminal angioplasty dissection were the indications for stent deployment in 15 and 3 patients, respectively. No operative deaths occurred, but 3 patients (16 percent) had early complications. Primary patency, as determined by life table analysis, was 100 percent, 79 percent, 62 percent, and 51 percent at 1, 2, 3, and 5 years, respectively. Secondary patency at 1, 2, 3, and 5 years was 100 percent, 93 percent, 75 percent, and 63 percent, respectively, with a mean follow-up of 41 months., Conclusions: The combination of percutaneous transluminal angioplasty with primary or secondary stent deployment and femorofemoral bypass can be a useful option for treating iliac occlusion and contralateral iliac stenosis of less than 3 cm in length when the severity of the comorbid illnesses, advanced age, or the presence of prohibitive intra-abdominal pathology makes the avoidance of an abdominal incision desirable.

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.

Purpose: To evaluate the feasibility, safety, and efficacy of intravascular stents in the treatment of extracranial carotid artery occlusive disease., Methods: According to protocol, stent therapy was offered to symptomatic patients with > or = 70% arteriographically defined carotid stenoses or ulcerative lesions and, after September 1994, to asymptomatic patients with > or = 75% stenoses. From April 1993 to September 1995, 110 nonconsecutive patients (79 males; mean age 72 years, range 45 to 85) consented to participate in the study. The majority (79 [72%]) were asymptomatic. Lesions meeting the treatment criteria were in the proximal common (n = 3); mid common (n = 12); distal common (n = 8); internal (ICA) (n = 92); and external (n = 2) carotid arteries. Seven patients had bilateral ICA stenoses, and 17 patients were treated for postsurgical recurrent disease. The mean lesion length and diameter stenosis for all lesions were 12.4 +/- 9.2 mm and 86.5% +/- 10.6%, respectively. The procedures were performed either via direct percutaneous access to the cervical common carotid artery or through a retrograde femoral artery approach. Standard balloon dilation preceded deployment of balloon-expandable stents in most cases. No postprocedural anticoagulation was used (aspirin only)., Results: In 110 patients (117 arteries) intended for treatment, 109 (99.0%) (116 arteries [99.1%]) were successfully treated with 129 stents (128 Palmaz, 1 Wallstent). One percutaneous procedure failed (0.9%) for technical reasons (stent could not be deployed) and was converted to carotid endarterectomy. Minor complications included 4 cases of spasm (successfully treated with papaverine); 1 flow-limiting dissection (stented); and 6 access-site problems. There were 7 strokes (2 major, 5 reversible) (6.4%) and 5 minor transient events (4.5%) that resolved within 24 hours. Three patients were converted to endarterectomy (2.7%) prior to discharge; 1 stroke patient expired (0.9%), and another patient died of an unrelated cardiac event in hospital. In the 30-day postprocedural period, 2 ICA stents occluded (patients asymptomatic). Clinical success at 30 days (no technical failure, death, endarterectomy, stroke, or occlusion) was 89.1% (98/110). Over a mean 7.6-month follow-up (range 2 to 31), no new neurological symptoms developed. Another stent occlusion at 2 months and one case of flow-limiting intimal hyperplasia at 7 months were detected on routine duplex scanning in asymptomatic patients. Life-table analysis shows an 89% cumulative primary patency rate., Conclusions: Based on this early experience, carotid stenting appears feasible from a technical standpoint, with good midterm patency. However, the incidence of neurological sequelae is a serious problem. Technical enhancements and a more aggressive antiplatelet regimen may have a positive impact on these events.

Purpose: To report the results of the FDA phase II, multicenter trial of the Wallstent in the iliac and femoral arteries., Patients and Methods: Two hundred twenty-five patients entered the trial. Stents were placed in the iliac system in 140 patients and in the femoral system in 90 (five patients required both iliac and femoral stents). Clinical patency was measured over 2 years by means of life-table analysis with use of clinical and hemodynamic data and the Rutherford scale. Angiographic patency was measured at 6 months., Results: In the iliac system the primary clinical patency was 81% at 1 year and was 71% at 2 years. The secondary clinical patency was 91% and 86%, respectively. The 6-month angiographic patency was 93%. In the femoral system the primary clinical patency was 61% at 1 year and 49% at 2 years. The secondary patency was 84% and 72%, respectively. The 6-month angiographic patency was 80%., Conclusions: The results are similar to those with the Palmaz stent in the iliac system and with angioplasty alone in the iliac and femoral systems.

Purpose: To examine whether endoluminal grafts (ELGs) of radically expandable polytetrafluoroethylene (PTFE) can successfully form durable internal conduits to revascularize lengthy occlusive disease and exclude aneurysms in the femoropopliteal (FP) arteries., Methods: Under protocol, implantation of an unpredilated PTFE tube ELG anchored with Palmaz stents using a low-profile percutaneous delivery system was attempted in 50 symptomatic patients for a variety of pathologies: (1) restenosis; (2) complex lesions unlikely to be treated successfully with other endoluminal therapies; (3) acute angioplasty failure; and (4) aneurysms. There were 37 occlusions, 14 stenoses, and 2 long, combined stenotic-aneurysmal lesions in 47 native arteries, 5 FP grafts, and 1 femorotibial (FT) vein graft. Thirty-two percent of the patients had < or = vessel runoff. The average lesion length was 20.4 +/- 11.4 cm (range 1.5 to 40), and the mean preoperative ankle-brachial index (ABI) at rest was 0.53 +/- 0.14., Results: In a 20-month period through April 1995, 50 patients (34 males, 16 females; mean age 69.5 years, range 45 to 87) underwent 54 procedures in 53 limbs; 55 ELGs were successfully deployed in 51 limbs; 2 patients were converted to FP bypass owing to technical problems (96% procedural success). There were 18 inhospital complications: 1 distal wire dissection repaired with an additional ELG; 2 hematomas requiring surgical repair; 1 graft collapse; 1 pseudoaneurysm at the site of a mid-ELG leak; 7 minor access sequelae; and 6 acute ELG thromboses, 4 treated with lytic therapy and balloon dilation, 1 with open thrombectomy, and 1 with bypass grafting. The mean postoperative ABI was 1.01 +/- 0.10. During the 30-day postprocedure period, 2 ELGs rethrombosed and 2 other limbs (3 ELGs) occluded; 1 thrombosis and 1 rethrombosis were lysed successfully, but the other 2 patients had an FP bypass. Over the mean 8.3 +/- 5.5 month follow-up, 6 additional ELGs occluded and 1 reoccluded; 4 were successfully treated by endovascular techniques for a primary patency of 72% and secondary patency of 84% by life-table analysis., Conclusions: Endovascular grafting is a conceptually attractive technique that has the potential to expand the current boundaries of interventional treatment. This preliminary experience attests to the feasibility and safety of ELG deployment in the superficial femoral arteries. Whether such a device can match the durability of classical revascularization techniques remains to be determined in clinical trials when device configurations and deployment techniques have been standardized.

Potential early complications of balloon angioplasty include occlusion due to vessel wall recoil, medial dissection, creation of intimal flaps, spasm and luminal thrombosis. These features have also been implicated in the development of restenosis and late occlusion. As a possible solution to these problems, an endovascular scaffold (stent) was proposed by Dotter in the 1960s, and initial studies suggested that use of such a device in specific circumstances may reduce complications related to major dissection, vessel recoil and spams. This paper reports the utility of two- and three-dimensional intravascular ultrasound (IVUS) imaging in assessing arterial morphology following balloon angioplasty, and guiding the need for, and adequacy of deployment of intravascular stents. IVUS imaging provides a technique to accurately assess the immediate results of angioplasty and examine both the luminal size and contour following intervention. Accurate imaging such as this is essential for the successful use of balloon expandable stents, by ensuring correct initial positioning and complete deployment at the time of balloon expansion. Two cases are reported which highlight the important issues which are critical to the ongoing development of endovascular therapies: (i) accurate assessment of the angioplasty results, and (ii) selection and confirmation of stent deployment. We conclude that IVUS imaging may provide a new standard for the assessment of angioplasty procedures and will play a pivotal role in identifying failure mechanisms of endovascular interventions.

The opportunities to avoid surgical treatment of distal abdominal aortic occlusive disease are expanding because of the proliferation in catheter-based techniques. Since January 1990, 24 symptomatic patients with distal abdominal disorders have been treated percutaneously with balloon angioplasty and intraluminal stenting. A total of 38 Palmaz stents were deployed at distal abdominal aortic sites; 21 additional iliac stents were implanted. After the procedure all patients improved clinically, and 83% (21/24) improved by objective measurement (average ABI 0.93 +/- 0.21). Three access-related complications occurred (two hematomas, one thrombus), but no complications were related to the stents. At up to 29 months of follow-up (average 10.3 +/- 6.7 months), clinical improvement persists in all patients (average ABI 0.93 +/- 0.22). In 11 patients eligible for follow-up aortography, all aortic stents are patent without evidence of restenosis. With the low likelihood for restenosis in the abdominal aorta, the long-term outcome of aortic stenting looks promising and may equal or surpass that found in the iliac region.

This article compares the accuracy of commonly used oculoplethysmography (OPG) equipments--OPG/Gee, OPG/Kartchner, and OPG/Zira--in the detection of significant carotid stenosis. The first 200 patients (400 carotid arteries) with readily available carotid arteriograms were selected from each of the following categories: OPG/Kartchner, OPG/Gee, and OPG/Zira, making a total of 600 patients. The radiologic findings were divided into two categories: the first included patients with normal carotid arteries or vessels with less than 50% stenosis, and the second included patients with carotid stenosis greater than or equal to 50%. The results of OPG/Zira, OPG/Kartchner, and OPG/Gee are listed respectively: diagnostic sensitivity of 88.88%, 92.6%, and 96.0%; diagnostic specificity of 86.77%, 90.7%, and 91.8%; false positive rate of 6.0%, 5.1%, and 3.6%; false negative rate of 22.7%, 13.0%, and 8.9%; overall diagnostic accuracy of 88.25%, 92.0%, and 94.8%; and accuracy in determining bilateral carotid stenosis of 66.0%, 79.0%, and 89.5%. We concluded that the three machines were valuable in the diagnosis of normal carotid arteries and significant unilateral carotid stenosis. However, the OPG/Gee had slightly better overall accuracy and was more valuable in the diagnosis of significant bilateral carotid stenosis. The OPG/Kartchner had the advantage of being applicable in patients with extreme hypertension and cardiac arrhythmias. The OPG/Zira was limited in the diagnosis of bilaterally significant carotid stenosis.

One hundred and twenty-five patients received both lower limb arterial Doppler ultrasonics examinations and arteriographic tests. From the 250 limbs, 963 segments--iliofemoral, femoral, popliteal and popliteal trifurcation--were measured. Arteriography confirmed 649 of the 673 normal ultrasound results, while of the 290 abnormal ultrasound tests, 261 were documented by arteriography. Combining all segments, 910 were accurately defined by the Doppler ultrasonic technique for a reliability factor of 95 per cent. This simple, inexpensive, noninvasive technique was judged to be highly reliable in detecting and assessing occlusive lesions of the peripheral arterial system, making it a valuable adjunct to the evaluative procedure for patients with peripheral vascular occlusive disease.

We studied 150 arterial Doppler examinations on 150 patients by obtaining segmental pressures and the analogue wave tracings, and comparing the ankle/arm index to the arteriograms. Each limb was divided into iliofemoral, femoral, popliteal, and trifurcation segments. Of the 793 segments interpreted as normal by arterial Doppler, 758 were confirmed, with 96% true-negative and 4% false-negative results. Of 364 segments shown by arterial Doppler to be abnormal, 328 were confirmed by the arteriogram, ie, 90% true-positive and 10% false-positive results. Thus, a total of 1,157 segments were studied, with 94% correlation with the arteriogram in localizing the peripheral vascular occlusive disease. The ankle/arm index is helpful in determining the severity of the disease. The majority of patients with an ankle/arm index of 0.6 to 0.8 have significant disease. An index of less than 0.6 is indicative of severe disease.