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Objective: Carotid angioplasty and stenting (CAS) is used in patients considered high-risk for carotid endarterectomy (CEA). Patients qualify as high-risk because of medical comorbid conditions or for anatomic considerations (previous CEA, radical neck dissection, radiation). We compared the technical feasibility and durability of CAS in medically high-risk patients (MED) vs anatomically high-risk patients (ANAT)., Methods: A retrospective review was performed of all consecutive patients undergoing CAS by a single vascular surgery group. All patients were high risk and evaluated with duplex ultrasound imaging and angiography. Primary end points were technical success, 30-day stroke, myocardial infarction (MI), death, and in-stent restenosis. Standard statistical analysis included Kaplan-Meier life tables., Results: From January 2003 to December 2007, 230 CAS (98 ANAT, 132 MED) procedures were attempted. The ANAT cohort comprised 84 patients with a single anatomic risk factor: 71 with a previous ipsilateral CEA, 6 high lesions, 6 history of neck radiation, and 1 with a tracheostomy. Ten patients had two or three anatomic risk factors: nine with radical neck dissection and radiation and one with neck radiation and ipsilateral CEA. The mean age was 71.1 years for ANAT vs 73.9 years for MED (P = .021). Technical success rates were 98% in ANAT and 98.5% in MED (P = .76). Thirty-day stroke rate was 1.0% in ANAT and 5.3% in MED (P = .14); the mortality rate was 2.0% in ANAT and 0.8% in MED (P = .79). The 2-year survival free from stroke was MED, 93.6% and ANAT, 98.9% (P = .118); and from restenosis was MED, 91.9%; and ANAT, 91.0% (P = .98). Two-year overall survival was significantly better in ANAT (84.6%) vs MED (70.1%; P = .026). Four of the seven restenoses in the ANAT group occurred in patients with previous neck radiation. The restenosis rate for radiation-induced (RAD) stenosis treated with CAS was significantly higher at 22.2% (4 of 18) compared with 3.8% (3 of 78) in ANAT group patients without a history of radiation (non-RAD; P = .028). The 2-year restenosis-free survival was 72.7% in the RAD group vs 95.9% in the non-RAD group (P = .017)., Conclusion: CAS is as technically feasible, safe, and durable in anatomically high-risk patients as in medically high-risk patients, with similar rates of periprocedural stroke and death and late restenosis. However, patients with radiation-induced stenosis appear to be at an increased risk for restenosis.

Objective: The PREVENT III study was a prospective, randomized, double-blinded, multicenter phase III trial of a novel molecular therapy (edifoligide; E2F decoy) for the prevention of vein graft failure in patients undergoing infrainguinal revascularization for critical limb ischemia (CLI)., Methods: From November 2001 through October 2003, 1404 patients with CLI were randomized to a single intraoperative ex vivo vein graft treatment with edifoligide or placebo. After surgery, patients underwent graft surveillance by duplex ultrasonography and were followed up for index graft and limb end points to 1 year. A blinded Clinical Events Classification committee reviewed all index graft end points. The primary study end point was the time to nontechnical index graft reintervention or major amputation due to index graft failure. Secondary end points included all-cause graft failure, clinically significant graft stenosis (>70% by angiography or severe stenosis by ultrasonography), amputation/reintervention-free survival, and nontechnical primary graft patency. Event rates were based on Kaplan-Meier estimates. Time-to-event end points were compared by using the log-rank test., Results: Demographics, comorbidities, and procedural details reflected a population with CLI and diffuse atherosclerosis. Tissue loss was the presenting symptom in 75% of patients. High-risk conduits were used in 24% of cases, including an alternative vein in 20% (15% spliced vein and 5% non-great saphenous vein) and 6% less than 3 mm in diameter; 14% of the cases were reoperative bypass grafts. Most (65%) grafts were placed to infrapopliteal targets. Perioperative (30-day) mortality occurred in 2.7% of patients. Major morbidity included myocardial infarction in 4.7% and early graft occlusion in 5.2% of patients. Ex vivo treatment with edifoligide was well tolerated. There was no significant difference between the treatment groups in the primary or secondary trial end points, primary graft patency, or limb salvage. A statistically significant improvement was observed in secondary graft patency (estimated Kaplan-Meier rates were 83% edifoligide and 78% placebo; P = .016) within 1 year. The reduction in secondary patency events was manifest within 30 days of surgery (the relative risk for a 30-day event for edifoligide was 0.45; 95% confidence interval, 0.27-0.76; P = .005). For the overall cohort at 1 year, the estimated Kaplan-Meier rate for survival was 84%, that for primary patency was 61%, that for primary assisted patency was 77%, that for secondary patency was 80%, and that for limb salvage was 88%., Conclusions: In this prospective, randomized, placebo-controlled clinical trial, ex vivo treatment of lower extremity vein grafts with edifoligide did not confer protection from reintervention for graft failure.

Autologous arteriovenous access is the key to long-term success with hemodialysis and is strongly supported by the National Kidney Foundation's Dialysis Outcomes Quality Initiative guidelines. Basilic vein transposition (BVT) fulfills the need for a durable conduit with high patency and maturation rates. This retrospective review examines a single group's experience with this procedure. All patients undergoing BVT for hemodialysis with available follow-up data were reviewed. Telephone interviews were used to supplement clinical data where needed. Functional assisted patency was used as the end point for this procedure, and if the access was never used for dialysis, then the patency was considered zero. Secondary interventions performed while the access remained patent and in use were not considered detrimental to the patency reported. One hundred seventy BVTs in 162 patients were performed between November 1992 and October 2001. There were 87 women (53.7%) and 112 black patients (69.1%); hypertension was present in 138 patients (85.2%) and diabetes in 89 patients (54.9%). Each year, an increasing incidence of BVT was performed in our dialysis population. The BVT was performed as the first access in that extremity in 73 of the procedures (42.9%). Functional patency (primary assisted) was achieved in 40.0% at 2 years and 15.2% at 5 years. The mean assisted patency was 14.6 months. To maintain BVT patency, 40 percutaneous secondary interventions (69.0%) and 18 surgical revisions (31.0%) occurred in 32 patients (19.0%). Ligation for swelling was necessary in 4 patients (2.5%), and steal syndrome occurred in 3 patients (1.9%). BVT is a useful autologous procedure for hemodialysis and the preferred access alternative in patients without an adequate cephalic vein. Although patencies remain poor relative to other conventional arterial vascular procedures, BVT is our most durable hemodialysis access procedure and is often the only available autologous conduit for hemodialysis.

Clinical management of carotid disease is primarily based on results of national trials (ACAS and NASCET) that used the distal internal carotid artery diameter as a reference. However, commonly accepted ultrasound (US) criteria for carotid stenosis were derived from the correlation of velocity measurements with angiographic bulb diameter reductions (BDR). This study was undertaken to compare the degree of carotid stenosis determined by conventional velocity criteria to the degree of stenosis measured by B-mode (gray scale) diameter at both the carotid bulb and at the distal internal carotid artery, and, second, to evaluate US imaging to derive distal diameter reductions (DDR) noninvasively. During a 3-month period patients referred for carotid US were prospectively analyzed for standard velocity criteria and plaque morphology. Minimum carotid diameter was measured by longitudinal and transverse B-mode measurements and compared to carotid bulb diameter and internal carotid diameter distal to all disease. B-mode diameter reductions were compared to the degree of stenosis determined by velocity criteria and to patient symptoms and the decision for carotid endarterectomy. In total, 131 carotid arteries in 74 patients were evaluated. Based on the University of Washington velocity criteria, lesions were classified as grade I (n = 61, 46%), IIA (n = 58, 44%), IIB (n = 7, 5%), or III (n = 5, 4%). BDR measured by B-mode predicted the grade of disease based on velocity criteria (p < 0.001) with an overall accuracy of 95%. With use of the B-mode for DDR (NASCET style), 18 patients exceeded the 60% threshold for surgical intervention. Of these, only 3 patients were symptomatic and were operated on. An additional 3 operated-on patients had an asymptomatic grade III stenosis, our usual threshold for intervention. Twelve additional patients were appropriate for surgical intervention by B-mode but were not treated based on conventional velocity criteria alone. Bulb diameter reduction by B-mode imaging correlates strongly with diameter reduction determined by velocity criteria, and independently predicts the grade of carotid disease. With this in mind, the accuracy of B-mode imaging may be extended to the measurement of carotid stenosis based on DDR. By B-mode criteria, many patients appropriate for intervention were not offered treatment based on conventional velocity criteria. Modern B-mode imaging provides a noninvasive method to obtain 'arteriographic equivalent'' measurements and should be added as a routine to carotid ultrasound interrogation.

Objectives: The endovascular management of abdominal aortic aneurysm (AAA) relies on accurate preoperative imaging for proper patient selection and operative planning. Three-dimensional (3-D) computed tomography (CT) with reformatted images perpendicular to blood flow has gained popularity as a method of AAA assessment and image-based planning before endovascular aneurysm repair (EVAR). The current study was undertaken to determine the interobserver agreement of AAA measurements obtained with axial CT and reformatted 3-D CT and to compare the consistency of the 2 methods in selecting patients for EVAR., Methods: Eight observers assessed the axial CT and reformatted 3-D CT scans for 5 patients with AAAs to determine whether the patients were candidates for EVAR. 3-D CT with multiplanar reformatted images was performed by Medical Media Systems (MMS). Each observer measured the length and diameter of the proximal neck, maximal AAA, aortic bifurcation, common iliac diameter, and aortic angulation. The proximal neck and common iliac arteries were also assessed for thrombus, calcification, and tortuosity. Agreement of the measurements on axial CT scans was compared with those on MMS CT scans by calculating the kappa statistic. Complete agreement was defined as kappa = 1.0. The limits of agreement between observers were also calculated., Results: The cumulative interobserver agreement of MMS CT scans (kappa =.81) was greater than for axial CT scans (kappa =.59). The kappa value for each of the diameter measurements was greater with the MMS CT scans. In 79% of cases the observers' measurements were less than 2 mm from the mean with MMS CT, compared with 59% for axial CT. The kappa value for deciding whether a patient was an endograft candidate on the basis of aortic neck was greater with the MMS CT (0.92 vs 0.63). The limits of agreement between observers were also better with the MMS CT., Conclusions: The interobserver agreement in planning EVAR is significantly better with MMS CT compared with traditional axial CT. The routine use of MMS CT appears justified before EVAR to improve the accuracy and consistency of patient selection.

Objective(s): Clinical assessment of maximal abdominal aortic aneurysm (AAA) diameter assumes clinical equivalency between ultrasound (US) and axial computed tomography (CT). Three-dimensional (3D) CT reconstruction allows for the assessment of AAA in the orthogonal plane and avoids oblique cuts due to AAA angulation. This study was undertaken to compare maximal AAA diameter by US, axial CT, and orthogonal CT, and to assess the effect that AAA angulation has on each measurement., Methods: Maximal AAA diameter by US (US(max)), axial CT (axial(max)), and orthogonal CT (orthogonal(max)) along with aortic angulation and minor axis diameters were measured prospectively. Spiral CT data was processed by Medical Media Systems (West Lebanon, NH) to produce computerized axial CT and reformatted orthogonal CT images. The US technologists were blinded to all CT results and vice versa., Results: Thirty-eight patients were analyzed. Mean axial(max) (58.0 mm) was significantly larger (P<0.05) than US(max) (53.9 mm) or orthogonal(max) (54.7 mm). The difference between US(max) and orthogonal(max) (0.8 mm) was insignificant (P>0.05). When aortic angulation was <==25 degrees, axial(max) (55.3 mm), US(max) (54.3 mm), and orthogonal(max) (54.1 mm) were similar (P>0.05); however, when aortic angulation was >25 degrees, axial(max) (60.1 mm) was significantly larger (P<0.001) than US(max) (53.8 mm) and orthogonal(max) (55.0 mm). The limits of agreement (LOA) between axial(max) and both US(max) and orthogonal(max) was poor and exceeded clinical acceptability (+/-5 mm). The variation between US(max) and orthogonal(max) was minimal with an acceptable LOA of -2.7 to 4.5 mm., Conclusion: Compared to axial CT, US is a better approximation of true perpendicular AAA diameter as determined by orthogonal CT. When aortic angulation is greater than 25 degrees axial CT becomes unreliable. However, US measurements are not affected by angulation and agree strongly with orthogonal CT measurements.

Objectives: The increased use of central venous access primarily for hemodialysis has led to a significant increase in clinically relevant central venous occlusive disease (CVOD). The magnitude of and the optimal therapy for CVOD are not clearly established. The purpose of this study is to define the problem of CVOD and determine the success of percutaneous therapy for relieving symptoms and maintaining central venous patency., Methods: Patients presenting with disabling upper-extremity edema suggestive of central venous stenosis or occlusion during a 3-year period were evaluated by venography of the upper extremity and central veins. Percutaneous venous angioplasty (PTA) and/or stent placement was performed as clinically indicated. The success of therapy was assessed, and the patients were observed to determine the incidence of recurrence and additional procedures. Recurrent lesions underwent similar evaluation and treatment., Results: A total of 32 sides were treated in 29 patients with a mean of 1.9 interventions per side treated. Hemodialysis-related lesions were the underlying cause in 87% with the remaining 13% related to previous central venous catheterization. The lesions involved the axillary, subclavian, and innominate veins with complete venous occlusion in six (19%) cases. Percutaneous angioplasty was followed by stent placement in six (19%) cases. The procedure was a technical success and was performed without complications in all cases (100%). Mean follow-up was 16.5 months (range, 4-36 months). On average, patient symptoms were controlled for 6.5 months after the initial intervention. Recurrent edema led to additional PTA in 20 (63%) cases. Fifty percent (n = 14) of patients with an arteriovenous fistula (AVF) experienced recurrent symptoms after initial and/or repeat PTA and required AVF ligation. Complete resolution after the initial PTA was predictive of long-term success., Conclusions: Central venous occlusive disease has emerged as a significant clinical problem. Percutaneous venous angioplasty can provide temporary symptomatic relief; however, multiple procedures are often required and long-term relief is rarely achieved.

Objectives: Accurate diameter measurements of abdominal aortic aneurysm (AAA) with both computed tomography (CT) and ultrasound (US) are essential for screening, planning surgical intervention, and follow-up after endovascular repair. Often there is a discrepancy between measurements obtained with CT and US, and neither limit of agreement (LOA) nor correlation between the two imaging methods has been clearly established. The purpose of this study was to assess the paired differences in AAA diameter measurements obtained with CT and US in a large national endograft trial., Methods: CT and US measurements were obtained from an independent core laboratory established to assess imaging data in a national endograft trial (Ancure; Guidant, Menlo Park, Calif). The study included only baseline examinations in which both CT and US measurements were available. Axial CT images and transverse US images were assessed for maximal AAA diameter and recorded as CT(max) and US(max), respectively. Correlations and LOA were performed between all image diameters, and differences in their means were assessed with paired t test., Results: A total of 334 concurrent measurements were available at baseline after endovascular repair. CT(max) was greater than US(max) in 95% (n = 312), and mean CT(max) (5.69 +/- 0.89 cm) was significantly larger (P <.001) than mean US(max) (4.74 +/- 0.91 cm). The correlation coefficient between CT(max) and US(max) was 0.705, but the difference between the two was less than 1.0 cm in only 51%. There was less discrepancy between CT(max) and US(max) for small AAA (0.7 cm, 15.3%) compared with medium (0.9 cm, 17.9%) and large (1.46 cm, 20.3%) AAA; however, the difference was not statistically significant. LOA between CT(max) and US(max) (-0.45-2.36 cm) exceeded the limits of clinical acceptability (-0.5-0.5 cm). Poor LOA was also found in each subgroup based on AAA size., Conclusions: Maximal AAA diameter measured with CT is significantly and consistently larger than maximal AAA diameter measured with US. The clinical significance of this difference and its cause remains a subject for further investigation.

Purpose: Temporal arteritis (TA) is frequently diagnosed with nonspecific clinical characteristics, followed by a temporal artery biopsy to confirm the presence of vasculitis. Consequently, numerous screening surgical biopsies are performed with a high negative-biopsy rate. A prospective study was performed evaluating color duplex ultrasound scan (CDU) as the preferred method for the diagnosis of vasculitis in the evaluation of suspected TA., Methods: Thirty-two patients with suspected TA on the basis of clinical criteria were evaluated with CDU before a temporal artery biopsy. The presence of a hypoechoic "halo," suggesting edema of the inflamed vessel, and inflammatory stenoses were noted. Histologic examinations of standard temporal artery biopsies then were performed, and the results were compared with the CDU findings. In addition, a metaanalysis was performed to identify articles related to the use of ultrasound scan in the detection of TA., Results: All patients completed a bilateral CDU examination of the temporal arteries, and in 75% of patients biopsied, no evidence of vasculitis was found at histologic examination. When CDU examined for halo alone as the determinant for disease, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), compared with histologic confirmation of TA, were 85.7%, 92.0%, 75.0%, and 95.8%, respectively. With the criteria for a halo sign present, an inflammatory stenosis present, or both present on CDU, the sensitivity, specificity, positive predictive value, and NPV were 100%, 80.0%, 58.3%, and 100%, respectively., Conclusion: CDU is a superior noninvasive method of determining the presence of vasculitis when compared with routine surgical biopsy. Examination of the temporal artery with CDU can effectively predict which patient will need surgical biopsy. The utility of CDU in the diagnosis of TA is maintained by a high sensitivity in detecting patients with the disease and also by a high NPV that can eliminate patients who would not benefit from biopsy.

Objective: The purpose of this study was to define the incidence and treatment of endograft limb stenosis or occlusion (endograft limb dysfunction [ELD]) in a single center with the ANCURE unsupported bifurcated or aortouniiliac endograft by using intraoperative completion angiography and postoperative color duplex ultrasound scanning (CDU)., Methods: Sixty-seven endografts (58 bifurcated, 9 uniiliac) were implanted between February 1996 and July 2000. Intraoperative completion aortography was performed in every patient. Postoperative assessment of the endograft consisted of CDU and computed tomography scanning and kidney, ureter and bladder radiographs within 7 days of implantation, at 3 and 6 months after the operation, and every 6 months thereafter., Results: At the time of endograft implantation, widely patent normal-appearing endograft limbs were revealed by means of the initial completion angiogram in 58 of 67 patients (group 1). ELD subsequently developed in seven of these 58 patients (13.4%). The results of the completion angiogram were not normal in the remaining nine patients (group 2), leading to the deployment of a self-expanding stent within the endograft limbs. The results of subsequent angiography were normal. No ELD has occurred in any patient in group 2 to date. The primary assisted patency rate at 30 months was 88% +/- 5.2% for group 1 versus 100% +/- 0% for group 2 (P = not significant, Log-rank test). Postoperative ELD occurred in seven patients (10.4%). Endovascular graft thrombosis occurred in three patients (3 endograft limbs). In each case, an endovascular approach was attempted; however, the guidewire would not traverse the occluded endovascular graft limb. Revascularization was accomplished by means of femorofemoral bypass grafting. Endovascular graft stenosis occurred in four patients (4 endograft limbs). Three patients with bifurcated endografts and limb stenosis who had no symptoms diagnosed by means of CDU were successfully treated by means of balloon angioplasty with self-expanding stent implantation, and the endograft limbs remained patent at 3, 5, and 26 months follow-up. The remaining patient who had an aortouniiliac endograft with recurrent severe stenoses underwent endograft explantation and aortobifemoral bypass grafting. The overall incidence of ELD during or after endovascular abdominal aortic aneurysm repair was 23.8% (16 of 67 patients)., Conclusion: Unsupported endografts are at risk for developing ELD. The use of stents for limb support at the time of the initial endograft implantation may prevent subsequent ELD and bears further study. Endograft limb occlusion usually presents with acute severe ischemic symptoms, and the failure of operative thrombectomy necessitates femorofemoral artery bypass grafting. Endograft limb stenosis is identified by means of CDU surveillance in the postoperative period. Prompt treatment with percutaneous transluminal angioplasty/stent yields satisfactory primary assisted patency. Intraoperative intravenous ultrasound scanning, oblique angiograms, pressure gradients, and completion angiography may be necessary to detect and treat ELD.

Purpose: The purpose of this study was the demonstration of the value of color duplex ultrasound (CDU) scanning in the detection of type I endoleak (T1EL) and type II endoleak (T2EL), the correlation of Doppler scan waveform pattern to endoleak persistence or seal, and the description of the natural history of endoleak., Methods: The study was a retrospective review of 83 patients who underwent periodic CDU scan and computed tomographic (CT) scan surveillance of the endograft and aneurysm sac after insertion of an aortic endograft for abdominal aortic aneurysm (AAA). Forty-one patients (49%) with an endoleak at anytime in the follow-up period form the basis of this report., Results: T1EL was detected in all five patients with CDU and CT scans. T2EL was detected in 36 patients with CDU scan as compared with 18 patients with CT scan. With CT scan, endoleak was not detected when CDU scan showed no endoleak. Conversely, all CT scan--detected endoleaks were found with CDU scanning. The T2EL source artery was identified with CT scan in seven patients, whereas the source was identified in all 36 patients with CDU scan. Endoleak source did not correlate with outcome (seal or persistence). However, a to/fro Doppler scan waveform pattern was associated with spontaneous T2EL seal in seven of 12 patients, and a monophasic or biphasic waveform was associated with endoleak persistence in 14 of 17 patients (P =.023, with chi(2) test). Thirteen of 36 T2ELs underwent spontaneous seal by 6.2 +/- 2.8 months. T2ELs without increasing AAA diameter were observed. Eight patients with persistent T2EL present for more than 12 months did not undergo treatment. However, two patients underwent T2EL obliteration with coils because of AAA sac enlargement. T1EL of the distal attachment site was the initial endoleak identified in five patients, but seven patients harboring T2ELs had subsequent T1ELs develop. For the entire 83 patients, the combined T1EL and T2EL prevalence rate was 20% of patients at a 6-month follow-up period, but this rate increased to 50% after 24 months. The incidence rate of newly detected endoleaks and of spontaneous sealing was 24.4% at 12 months and 12.5% in longer-term follow-up period., Conclusion: CDU scan is effective in the identification of the type of endoleak, the delineation of the vessel involved, and the hemodynamic information not available with any other testing method. Endoleaks have a dynamic natural history characterized by a variable onset with changing branch vessel involvement and spectral flow patterns. Periodic long-term endograft surveillance with CDU scanning is necessary for following existing endoleaks and for detecting new ones. Corroboration of these findings in larger multicenter prospective trials will be needed to determine whether CDU scan analysis of endoleaks would be predictive of long-term success in endovascular AAA repair.

Purpose: The expansion of aneurysms after endovascular repair is a consequence of persistent sac pressure, usually resulting from an endoleak. Several authors have suggested that sac expansion can occur even in the absence of endoleak, referring to this phenomenon as endotension. This study undertakes a review of the largest US endograft trial data to better define the significance of aneurysm expansion in the absence of endoleak., Methods: The core laboratory imaging database from the Ancure (Guidant) endovascular graft Phase I and Phase II trials approved by the Food and Drug Administration was reviewed with attention to aneurysm size and endoleak. Aneurysm size was measured with standardized two-dimensional computed tomography (CT) scan at the area of largest initial aneurysm diameter. Endoleak was detected with CT scans, color duplex ultrasound scans, and angiography in selected cases. Patients were evaluated at baseline, 3 months, 6 months, 12 months, and every 12 months thereafter. An endograft was classified as leaking if any endoleak was detected with any modality at any time point., Results: A total of 658 patients were entered into these protocols and the data submitted to the core laboratory. A control group of 120 conventional aortic patients and a group of 62 without baseline CT data were excluded from further analysis. Of the remaining 476 patients, 144 (60 tube, 60 bifurcated, and 24 mono-iliac) were free of endoleak at all intervals and had baseline CT measurements to allow comparison. Overall, the average size decrease in this nonleaking group was 9.9 +/- 9.4 mm (range, -50.6-11.1 mm) at a mean follow-up of 23.3 months. Evaluation for overall aneurysm expansion revealed 17 patients who had an increase of 2.3 +/- 2.9 mm (range, 0.3-11.1 mm) at a mean follow-up of 14.1 months. Only two patients without evidence of endoleak exhibited growth of more than 5 mm at maximum follow-up (7.6 mm at 12 months and 11.1 mm at 36 months). Additional analysis of sealed endoleaks and late endoleaks failed to demonstrate any group with expansion in the absence of detectable endoleak., Conclusions: Endotension appears to be rare in this large series of prospectively evaluated endografts. From this review, endotension seems more likely to represent missed endoleak than true aneurysm expansion in the absence of perigraft flow.

The development of steal syndrome distal to an arteriovenous fistula (AVF) created for hemodialysis access remains a significant clinical problem. This study was undertaken to determine the role of intraoperative noninvasive testing in the prediction and management of steal syndrome following arteriovenous fistula creation. First, in order to determine a threshold digital/brachial index (DBI) for patients at risk for steal syndrome, we performed a retrospective review of patients who had had the DBI measured and who developed symptoms (steal syndrome) following AVF creation. This was followed by a prospective evaluation of the ability of the DBI to predict which patients undergoing AVF surgery would develop steal syndrome. A DBI of <0.6 identifies a patient at risk for steal syndrome. Intraoperative DBI cannot be used to predict which patient will develop steal syndrome; however, if revision is indicated, the DBI should be increased to >0.6. Failure to accomplish this puts the patient at risk for continued steal syndrome.

This study was undertaken to determine the safety and feasibility of inferior vena cava (IVC) filter insertion at the bedside using duplex imaging in multi-trauma and/or critically ill patients. From February 1996 to August 1997, 53 multi-trauma and/or critically ill patients, who were in the intensive care unit and referred for an IVC filter, were prospectively evaluated for possible duplex directed caval filter (DDCF) insertion. Screening IVC duplex scans were performed in all patients. Satisfactory ultrasound visualization in 46 patients (87%) allowed attempted DDCF insertion. All procedures were percutaneously performed at the bedside using Vena Tech IVC filters. The results from this series showed that DDCF insertion can be safely and rapidly performed at the bedside in multi-trauma or critically ill patients. The procedure is dependent on satisfactory visualization of the IVC by duplex ultrasonography, which was possible in 45 out of 53 (85%) patients. Insertion at the bedside substantially reduces the procedural cost and avoids the need for transport, radiation exposure, and intravenous contrast.

Purpose: To compare the outcomes and complications of open (OSPS) versus endoscopic subfascial perforator surgery (SEPS) for treatment of chronic venous insufficiency., Methods: Data were retrospectively collected on 25 patients who underwent 27 SEPSs from February 1996 to August 1997 and from 22 patients who underwent 29 OSPSs between March 1978 and May 1993. Outcomes were evaluated for postoperative complications, ulcer healing, recurrence, and venous dysfunction scores on the last follow-up for the SEPS group and at 1-year follow-up for the OSPS group., Results: The 2 groups were similar in age, sex, history of previous venous surgery, healed or active ulcers, etiology, deep venous incompetency, pathophysiology, and venous refill times. Eighteen (90%) of 20 active ulcers in the SEPS group healed with recurrences in 5 (28%) limbs at 7.5 +/- 5.4-month follow-up. All 19 ulcers in the OSPS group healed, with recurrences in 13 (68%) limbs at 35 +/- 35-month follow-up. Clinical venous dysfunction scores showed significant improvement following SEPS (10.0 +/- 3.6 to 5.4 +/- 4.1, p < 0.001) and OSPS (10.0 +/- 3.2 to 6.7 +/- 3.6, p < 0.001) with no significant difference between groups. Both groups also had significant improvement in anatomical and disability scores. There was no postoperative mortality in either group. The OSPS group had significantly more wound complications (45%) than the SEPS group (7%) (p < 0.005). The hospital stay and readmission rate for wound problems were also higher in the OSPS group., Conclusions: The early outcome showed equal improvement in clinical venous dysfunction scores in the 2 groups, but with significantly fewer complications in the SEPS group. Although the long-term durability of the endoscopic approach has not been determined, the short-term results would favor SEPS for treatment of severe venous insufficiency when perforator incompetence is a significant component.

Purpose: The purpose of this study was to compare the accuracy of a color duplex ultrasound scan (CDU) to a computerized axial tomography scan (CT) in the diagnosis of endoleaks after stent graft repair of abdominal aortic aneurysms., Methods: The Endovascular Aneurysm Clinical Trial Core Laboratory records were reviewed from 117 concurrent CDU and CT studies that were performed in 79 patients who were implanted with the Endovascular Technologies stent graft device between December 1995 and January 1997. All of the studies were interpreted by the Core Laboratory as having the presence or the absence of an endoleak or as being indeterminate because of technical factors. Of the 117 videotaped CDU studies available for reexamination, 100 were reassessed for technical adequacy on the basis of the following criteria: a satisfactory imaging of the aneurysm sac and of the stent graft with gray scale, and both color and spectral Doppler scan evaluation for endoleak outside the endograft and within the aneurysm sac., Results: Of the 117 studies, 103 CDUs (88%) and 114 CTs (97%) were recorded as having the presence or the absence of an endoleak and 14 CDUs (12%) and 3 CTs (3%) were indeterminate. For the studies that were recorded to have the presence or the absence of an endoleak, the sensitivity, the specificity, the positive and the negative predictive values, and the accuracy of CDUs as compared with CTs were 97%, 74%, 66%, 98%, and 82%, respectively. Of the 100 CDU videotaped studies available for review, the following results were seen: (1) 93 CDUs had satisfactory B-mode images, (2) 76 had satisfactory color Doppler scan images to evaluate for endoleaks, (3) 55 had color Doppler scan assessment of the entire abdominal aortic aneurysm sac for endoleak, and (4) 27 had spectral Doppler scan waveform confirmation of suspected endoleaks. Only 19 CDU studies (19%) with all 4 criteria for complete assessment of endoleak were performed., Conclusion: Although most of the CDU studies were technically suboptimal, the CDUs reliably identified endoleaks with an excellent sensitivity and a negative predictive value as compared with CT scans.

Objective: To determine factors of outcome following surgical intervention for neurologic thoracic outlet syndrome (NTOS)., Methods: In a retrospective study of patients surgically treated for NTOS, outcome was evaluated by postoperative symptoms and the ability of patients to return to work., Results: Good, fair, and poor results were obtained in 26 (48%), 21 (39%), and 7 (13%) patients, respectively. The best predictor of a good outcome was occupation. Nonlaborers were more likely to have good outcome (21 of 32, 66%) when compared with laborers (5 of 22, 23%; P = 0.0025). Only 6 of 20 (30%) laborers were able to return to their original occupation compared with 17 of 26 (65%) nonlaborers (P = 0.036)., Conclusions: Laborers with NTOS are less likely to have a good result from surgical intervention, are unlikely to return to their original occupation, and may require retraining for a non-labor-intensive occupation if they cannot return to their original work.

Purpose: To determine the long-term outcome and prognostic factors after early infrainguinal graft failure (< 30 days)., Methods: Retrospective analysis of limb salvage data, patency data, and prognostic risk factors in 112 new infrainguinal bypass grafts from 1985 to 1995 that occluded within 30 days of operation., Result: Thirty-six femoropopliteal and 76 femorotibial/femoropedal arterial bypass ("index") procedures were performed for rest pain (50%), tissue loss (31%), or disabling claudication (19%). In 103 patients, an immediate additional revascularization ("takeback") procedure was performed at the time of early graft failure. Life table analysis of the takeback procedures for threatened limbs (n = 84) revealed limb salvage rates of 74%, 54%, 40%, and 31% at 1 month, 1 year, 3 years, and 5 years, respectively. The 1-month limb salvage rate (threatened limbs) was 12% (1 of 8) in patients who were not taken back for revascularization and 33% (4 of 12) in patients who had undergone more than one takeback procedure within 30 days. The secondary graft patency rates for the takeback procedures (n = 103) were 70%, 37%, 27%, and 23% at 1 month, 1 year, 3 years, and 5 years, respectively. Univariate and life table analysis revealed that patients who were given anticoagulation medication after the index procedure (before graft thrombosis) or patients who had undergone previous ipsilateral leg revascularization had significantly lower rates of limb salvage and graft patency (p < 0.05). The limb salvage rate was also significantly worse in patients who had single-vessel runoff compared with those who had multiple-vessel runoff (p < 0.01). Thrombectomy and revision or complete graft replacement had a better secondary patency rate than thrombectomy alone (p < 0.05). Autogenous vein grafts had better outcome than polytetrafluoroethylene-containing grafts, but statistical significance was not achieved. No significant differences in limb salvage or graft patency rates were found between femoropopliteal versus femorotibial/femoropedal bypass grafting, age, gender, previous inflow surgery, diabetes, hypertension, smoking, or cardiac, renal, or pulmonary disease., Conclusion: The long-term limb salvage and graft patency rates after takeback revascularization procedures for early graft failure are poor. Despite poor outcome, a single takeback procedure appears warranted in all patients. Multiple takeback procedures, however, do not appear to be justified, especially in patients who are given anticoagulation medication after the index bypass procedure, repeat leg bypass procedures, or if there is no potential for graft revision.

The purpose of this study was to determine whether tourniquet occlusion could be safely used on the upper extremity for vascular control during hemodialysis access surgery. The hospital and outpatient records of 44 patients undergoing 105 hemodialysis access procedures were retrospectively reviewed. In 48 procedures tourniquet occlusion was used for vascular control, whereas in 57 procedures vascular clamps were used. In those procedures in which the tourniquet was used, the mean tourniquet time was 30 minutes and the mean tourniquet pressure was 242 mm Hg. The operative time was significantly less in the tourniquet group as compared to the clamp group (72.5 minutes vs. 84 minutes, respectively; p = 0.029). There was no statistically significant difference in the incidence of nerve injury, bleeding, hematoma, vascular steal, infection, or swelling between the two groups. There were no complications related specifically to the use of the tourniquet. There was no difference in primary patency in comparing the tourniquet control group with the clamp control group (p > 0.5). The use of a pneumatic tourniquet for vascular control during hemodialysis access surgery allows for a faster, technically easier operation with no increase in the complication rate and no effect on primary patency.

When infrageniculate lower extremity vascular reconstructions are required in the face of inadequate or insufficient autogenous vein, prosthetic-vein composite grafts remain a viable alternative. Graft patency and limb salvage for composite grafts are intermediate between those of completely autogenous and prosthetic bypasses alone. The sequential technique may offer superior patency in patients with the appropriate anatomy. The addition of adjunctive techniques such as a distal arteriovenous fistula and/or anticoagulation may further improve results. An algorithm illustrating the proper role of composite grafts for distal lower extremity reconstructions is shown in Figure 6. Any significant interval of patency is important in this group of patients in whom limb salvage can often be achieved by healing ischemic lesions and in whom overall life expectancy is limited.

Renal carcinoma (RCA) presenting in association with abdominal aortic aneurysm (AAA) is extremely rare, with only sporadic case reports previously described. The management of six cases of AAA and concomitant RCA presenting to a single institution from March, 1991 through December, 1993 was reviewed and management options considered. AAAs ranged in size from 4.5-7.0 cm (mean, 5.6 cm). Three left renal carcinomas were resected via a retroperitoneal approach simultaneous to repair of the AAA. One right renal carcinoma was resected in combination with repair of an AAA through a transperitoneal approach. The fifth case was managed by left nephrectomy, followed by interval aneurysmectomy, and the sixth case was managed by nonsurgical methods because of the presence of widely metastatic disease. Renal malignancies included five renal cell carcinomas and one transitional cell carcinoma. Three patients remain free of disease 8-11 months postoperatively, and one patient had metastatic disease detected 19 months postoperatively. Two deaths have occurred; one due to a massive CVA 1 month following a combined aneurysmectomy and left nephrectomy, and a second due to unknown etiology in the patient managed non-surgically. No peripheral vascular or aortic graft related complications have occurred. The treatment of AAA and RCA should be governed by the size of the AAA, the location of the cancer, and the extent of malignant disease. Simultaneous resection is safe and effective in patients with coexistent AAA and renal cancer. Left sided tumors should be resected via a retroperitoneal approach that also provides excellent exposure for simultaneous AAA resection.(ABSTRACT TRUNCATED AT 250 WORDS)

Iliac artery percutaneous transluminal angioplasty (PTA) can effectively provide in-flow for subsequent distal vascular reconstruction. Iliac artery stents may improve the initial hemodynamics and long term patency of PTA, and thus may be well-suited for combined proximal PTA with distal bypass procedures. This report reviews our preliminary experience with iliac artery stenting in combination with infra-inguinal vascular reconstruction. Thirteen iliac artery stent procedures combined with simultaneous distal revascularization were performed in 11 patients. Ten procedures were performed for limb salvage, two for disabling claudication, and one before planned orthopedic surgery. Distal revascularization procedures included seven femoropopliteal, four femorotibial bypasses, one common femoral endarterectomy, and one thrombectomy of a femoropopliteal bypass. Stent placement was technically successful in all patients. Mean pre-operative ankle-brachial index (ABI) was 0.41 (+/- 0.28), which improved to 0.91 (+/- 0.18) post-operatively (P < 0.0001). Mean systolic iliac artery gradients across the lesions improved from 27.1 (+/- 9.8) mm Hg to 2.7 (+/- 3.4) mm Hg after stent placement (P < 0.0001). Mean follow-up is 5.8 months (range 1-12 months). Two femoropopliteal bypass grafts occluded in the follow-up period. One occlusion was caused by a mid-vein graft stenosis that was repaired with subsequent graft patency. The other graft occlusion occurred in a patient with rest pain who did not require a second bypass procedure, as the ABI increased from 0.3 to 0.7 following stent placement with resolution of symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of brachiocephalic arterial lesions by percutaneous transluminal angioplasty (PTA) has only recently been performed with sufficient frequency to allow full assessment of its value. In this series, we report our results with PTA of 36 symptomatic subclavian stenoses in 33 patients seen from February 1981 through February 1992. Initial success rate was 94 per cent. There were no deaths and no CNS complications. Five minor complications occurred. Review of published surgical series suggests a similar early success rate but a significantly higher morbidity. These excellent early results of PTA and long-term results from other studies confirm that PTA of subclavian artery stenoses is a safe, highly effective procedure and should be considered the treatment of choice for symptomatic subclavian artery stenoses.

In 24 anesthetized open-chest dogs, we examined the time course of changes in contractile function, diastolic muscle stiffness (sonomicrometry), tissue water content, and ultrastructure after 1 hour of occlusion of the left anterior descending coronary artery and after 2 hours of unmodified reperfusion. One hour of occlusion of the left anterior descending artery replaced active shortening with passive bulging (21.4% +/- 2.9% versus -5.9% +/- 0.9%, p less than 0.05) in the involved segment. There was no increase in either subendocardial water content (78.6% +/- 0.1% versus 79.7% +/- 0.7%) or operative muscle stiffness (2.80 +/- 0.72 versus 2.36 +/- 0.42 mm Hg/mm) after the occlusion period. There were only mild to moderate ultrastructural alterations suggestive of reversible injury. In sharp contrast, reperfusion was associated with a 2.48% increase in subendocardial water content (p less than 0.05), a 42% increase in diastolic muscle stiffness (3.34 +/- 0.42 mm Hg/mm, p less than 0.05), and greater ultrastructural damage. We conclude that myocardial injury is significantly extended with unmodified blood reperfusion after temporary coronary occlusion.