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Endovascular aneurysm repair (EVAR) has undergone a tremendous evolution in the nearly 15 years since it was first described. Continual refinement of the technology and techniques associated with EVAR and the respectable short-term results of this procedure led the United States Food and Drug Administration to approve several devices for the endovascular treatment of abdominal aortic aneurysm (AAA). There has been a corresponding rapid dissemination of this technology throughout the vascular surgery community in the United States. Availability and critical analysis of mid- and long-term follow-up data on the increasing number of patients who have undergone EVAR has begun to raise questions about the long-term durability and effectiveness of EVAR. Numerous complications of EVAR are now recognized and well described in the literature. One of these is graft limb dysfunction. Graft limb occlusion occurs in a significant number of patients and it is imperative that physicians who perform EVAR have a thorough understanding of this condition. There are a variety of factors that predispose patients to development of graft limb occlusion. These factors can be classified as either anatomic or graft-related. When patients present with graft limb occlusion, endovascular treatment is usually possible and it is highly effective. Some cases require traditional surgical treatment. Prevention of graft limb occlusion is of paramount importance. It can only be achieved with an aggressive search for graft limb compromise and liberal use of angioplasty and/or stenting at the time of graft implantation.

Purpose: To evaluate the healing response of normal canine arteries to a self-expanding nitinol stent encapsulated in carbon-lined expanded polytetrafluoroethylene (ePTFE). Methods: Twenty-eight dogs were divided into aortic (n = 18) or iliac (n = 10) groups. In the latter, 2 animals were assigned to implantation intervals of 7, 30, and 90 days, respectively; 4 were designated for 180-day implantation. Half of the animals in each subgroup received a second overlapping stent-graft in one iliac artery. In the aortic cohort, 6 animals were assigned to the 180-day implantation group (2 with dual devices) and 3 to each of the others (1 dual implantation in each group). The devices were evaluated with angiography and intravascular ultrasound at implantation and explantation. After harvesting and gross examination, the specimens were examined microscopically and with scanning electron microscopy. Results: The 49 implanted devices (24 aortic and 25 common iliac) were all widely patent at explantation, save for 2 iliac stents that had moderate (Conclusions: The carbon-lined ePTFE-encapsulated stent is a novel approach to arterial stenting. The progressive endothelialization and lack of inflammatory reaction may provide improved long-term patency. Further study of this stent-graft design is warranted.

Objective: The objective of this study was to analyze a single-center experience in which descending thoracic aortic aneurysms (TAAs) were treated with a new self-expanding endovascular prosthesis (Medtronic AVE). Methods: Twenty-six patients (13 men, 13 women) with American Society of Anesthesiology grades II to IV and ages ranging from 53 to 92 years (average, 74 years) consented as part of a Phase I Food and Drug Administration–approved trial. Treated lesions included TAAs that were 5 to 10 cm in diameter, 12 diffuse dilations or fusiform aneurysms, and four saccular aneurysms. There were also nine chronic dissections (2 aneurysmal dilations and 7 symptomatic acute recurrent dissections). Three patients (2 with diffuse/fusiform and 1 with dissection) presented with hemothorax, contrast extravasation, or both. Results: Twenty-five of the 26 patients who consented (96% technical success) were treated successfully with no surgical conversions. Eighteen patients have been followed up from 1 to 22 months (average, 9 months). One patient is lost to follow-up, and six patients have died (24%). One procedure-related death (4%) occurred within the 30-day postoperative period and was caused by diffuse embolization. There were no device-related deaths. Five additional patients (20%) have died during the study of comorbid conditions. Complications included one massive myocardial infarction 24 hours after the procedure requiring balloon counterpulsation and long-term dialysis, one cardiac tamponade resulting from central line placement before the procedure, one progression of aneurysm dilation proximal to the device at 1 year, and one bilateral lower extremity paralysis occurring 12 hours after successful deployment. Seven patients (5 women) had femoral artery reconstructions or iliac artery grafts to repair injuries during deployment catheter passage. Other significant parameters included average procedure time (2 hours 40 minutes; range, 1 hour 30 minutes to 5 hours 30 minutes), 450 cc average blood loss (n = 25; 100-3000 cc) being replaced by means of autotransfusion with only two patients receiving banked blood products, and an average 2 days to resumption of normal diet, 1 day in the intensive care unit, and 5 days' hospitalization postprocedure in uncomplicated cases (n = 22). One patient had an endoleak immediately after the procedure that sealed without treatment. Follow-up of all patients ranging from 1 to 22 months (average, 9 months; n=18) demonstrates continued exclusion of the aneurysm with no endoleaks and either stable or decreasing aneurysm volume, except in one patient with volume increase and no obvious etiology who continues to be investigated. Conclusions: The study suggests that endovascular prosthesis exclusion of TAAs with an AneuRx self-expanding tubular device may be effective in many patients who are at significant risk for open surgical repair and substantiates further clinical investigation to confirm these findings.(J Vasc Surg 2001;33:927-34.)

Objective This study evaluated the value of operation for treatment of all octogenarians with ruptured abdominal aortic aneurysms (AAA). Summary background data Elective AAA resection in octogenarians is safe, with published operative mortality rates of approximately 5%. Published operative mortality rates of ruptured AAA in this age group, however, vary from 27 to 92%. Methods To evaluate this question, we extracted the clinical course of the 34 octogenarians submitted to AAA resection by the authors from our total experience of 548 resections performed during the past 7 1/2 years. In this subgroup of octogenarians, 18 underwent elective AAA replacement, 5 were submitted to urgent resection of active but intact AAAs, and 11 had operations for ruptured AAAs. There were 23 males and 11 females in the group. The ages ranged from 80 to 91 years. Results Operative mortality in the patients managed electively was 5.6%. Two of the five patients (40%) submitted to operation for active yet unruptured aneurysms died in the preoperative period. Finally, 10 of the 11 patients (91%) with ruptured AAAs were operative mortalities. All of these operative mortalities in the ruptured AAA subgroup had severe hypotension preoperatively (mean systolic blood pressure: 23 mm Hg). The charges associated with the management of the ruptured AAA group averaged $84,486 (range $12,537-$199,233). Conclusions Although elective replacement of AAA in properly selected octogenarians appears valuable to prolong worthwhile life expectancy, this experience leads us to consider observation only in the treatment of octogenarians with ruptured AAA who present with severe hemodynamic instability.

A 21-year-old male sustained a gunshot wound to the anterior right chest. The entrance wound was at the midclavicular line. He was haemodynamically stable upon arrival at the emergency department. He underwent initial resuscitation with intravenous fluids. There was no evidence of haemothorax or pneumothorax on chest X-ray. The right radial pulse was present but diminished when compared with the left. The patient had minor neurological symptoms in the right upper extremity, which consisted mainly of weakness of the interosseous muscles of the hand. An arteriogram was obtained, which revealed an arteriovenous fistula (AVF) of the right axillary artery and vein (Fig. 14.1a). The patient remained haemodynamically stable throughout the evaluation period.

A 77-year-old male presented to the emergency department with a 2-day history of increased swelling and pain in the left knee and distal thigh. He was unable to flex the knee without severe pain. On examination, the patient had a large pulsatile mass in the left popliteal fossa and distal thigh.

ObjectivesPoor outcomes have been reported with endovascular aneurysm repair (EVAR) in patients with hostile neck anatomy. Unsupported endografts with active fixation may offer certain advantages in this situation. We compared EVAR results using the Ancure (Guidant) endograft in patients with and without hostile neck anatomy.MethodsRecords of EVAR patients from October 1999 to July 2002 at a tertiary care hospital were retrospectively reviewed from a division database. Patients with elective open abdominal aortic aneurysm (AAA) repair during the same period were reviewed to determine those unsuitable for EVAR. Hostile neck anatomy, assessed by computer tomography (CT) scans and angiograms, was defined as one or more of the following: (1) neck length ≤10 mm, (2) focal bulge in the neck >3 mm, (3) >2-mm reverse taper within 1 cm below the renal arteries, (4) neck thrombus ≥50% of circumference, and (5) angulation ≥60 degrees within 3 cm below renals.ResultsThree hundred and twenty-two patients underwent EVAR with an average follow-up of 18 months. Patients in Phase II trials (n = 41), repaired with other graft types (n = 48), or without complete anatomic records (n = 27) were excluded. Demographics and co-morbidities were similar in the 115 good-neck (GN) and 91 bad-neck (BN) patients except for age (mean, 72.9 years GN vs 75.7 BN; P = 0.13), gender (11% female GN vs 22% BN; P =.04); neck length (mean, 21.8 mm GN vs 14.4 mm BN: P < .001), and angulation (mean, 22 degrees GN vs 40 degrees BN; (P < .001). Perioperative mortality (0 GN vs 1.1% BN), late mortality (5.2% GN vs 4.4% BN), all endoleaks (19.1% GN vs 17.6% BN), proximal endoleaks (0.8% GN vs 2.1% BN), and graft migration (0 for both groups) did not reach statistical significance. Neck anatomy precluded EVAR in 106 of 165 (64%) patients with open AAA.ConclusionsUnsupported endografts with active fixation can yield excellent results in treating many medically compromised patients with hostile neck anatomy. Nonetheless, an unsuitable neck remains the most frequent cause for open abdominal AAA.

To describe the endovascular exclusion of leaking thoracic aortic aneurysms (TAA).Two elderly patients with leaking TAAs who were at high risk for surgical intervention were transferred to our institution for possible endovascular treatment. Both patients underwent successful endovascular exclusion of the leaking TAAs using multiple stacked AneuRx thoracic endoprostheses. One patient remains alive and well at 1 year with an excluded aneurysm; the other patient died from heart failure 2 months after endografting.While the early results of the endovascular exclusion of leaking TAAs are promising, the use of thoracic endoprostheses remains investigational.

Objective: Placement of vena caval filters under fluoroscopic surveillance incurs significant expense and potential risks associated with the transportation of critically ill patients. Intravascular ultrasound (IVUS) allows direct intraluminal visualization of the vena cava and the renal veins. The purpose of this study is to evaluate the accuracy of vena caval filter placement under IVUS in an animal model. Methods: Fifteen Simon-Nitinol venal cava filters (C.R. Bard, Inc., Covington, GA) were placed under IVUS guidance into four anesthetized sheep. Twelve were placed transfemorally, and three were placed transjugularly. Accuracy of placement was confirmed with fluoroscopy by measurement between the filter tip and the targeted side branch. Results: The vena caval filters placed femorally averaged 0.33±0.42 cm distance from the target vein side branch. Jugular approach filter placement was less accurate. Although two out of three filters placed from the jugular vein were correctly positioned, the distance from the target vein side branch was much greater averaging 2.5±1.04 cm. Conclusion: Femoral placement of vena caval filters under IVUS is extremely accurate. The transjugular route, however, was technically challenging and standard fluoroscopic vena caval filter placement appears to be more appropriate. Our success with the femoral approach merits further clinical investigation in the use of IVUS for critically ill patients that would benefit from bedside vena caval filter placement.

Purpose: To describe an unusual presentation of impending aortic endograft rupture and successful endovascular rescue. Case Report: A 77-year-old man with an enlarging aortic aneurysm was treated with a Talent bifurcated endoprosthesis; a moderate endoleak that appeared to be related to either proximal or distal fixation sites was noted in the body of the aneurysm. The patient was observed for 1 month, and repeat imaging demonstrated persistent endoleak without major increase in the aneurysm diameter. Another examination was scheduled for 3 months hence, but, 2 months later, the patient presented with abdominal pain and a hemoperitoneum. A proximal extension cuff resolved the leak and led to resolution of the hemoperitoneum. Conclusions: A leaking aneurysm can be repaired using endovascular techniques in patients with an existing endograft. The need for frequent imaging surveillance of patients with endoleak is underscored.

Objectives: Assessment of the long-term function of endografts to exclude abdominal aortic aneurysm (AAA) includes determination of aneurysm dimensions and morphologic changes that occur after implantation. This study reports the dimensional analysis of patients treated with AneuRx bifurcated endoprostheses with postintervention, 1-year (n = 51), 2-year (n = 28), and 3-year (n = 10) postimplantation contrast computed tomography data. Methods: Maximal diameter (D) and cross-sectional area (CSA) of the AAA were measured from axial computed tomography images. Total volume, AAA thrombus volume (AAA volume minus the volume of the device and luminal blood flow), diameter of the aorta at the level of the renal arteries and within the device, distance from the renal arteries to the device, length of the device limbs, and the angle of the proximal neck were also determined at the same follow-up intervals after deployment with computed tomography angiograms reconstructed in an interactive environment. Results: Fifty-one of 98 consecutively treated patients with the AneuRx bifurcated prosthesis (29 “stiff” and 22 “flexible” body devices) had complete data from the postprocedure and follow-up computed tomography studies available for analysis. Max D, CSA, total volume of the AAA, and AAA thrombus volume decreased sequentially from year to year compared with the postimplantation values. D and CSA decreased or were unchanged in all except four patients, two who had unrestricted enlargement of the aneurysm with eventual rupture and one who had surgical conversion for continued expansion despite four diagnostic angiograms and attempted embolizations. Total volume of the AAA increased in 11 of 51 patients at 1 year, eight of whom had endoleaks at some interval during the follow-up. Thrombus volume increased more than 5% in four of these patients, including the two with eventual rupture and the one conversion. Patients with endoleaks who had spontaneous thrombosis or were successfully treated either remained at the same volume or had decreased volume on subsequent examinations. D at the renal arteries increased an average of 0.9 mm during the first year, with a concomitant increase of 2.8 mm within the proximal end of the device related to the self-expanding nature of the Nitinol suprastructure. Subsequent enlargement of the proximal neck continued at a slow rate in some cases but never exceeded the diameter of the endoluminal device. The distance from the renal arteries to the device increased by an average of 3 mm over the first year, with the greatest increases occurring in patients with a “stiff” body device and those with rapid regression (>10% total volume) in 1 year. As regression of the AAA occurred, the angle of the proximal neck varied from -5° to +25° from the original alignment. Limb length varied from -8 mm to +10 mm, with no consistent pattern for the change, that is, ipsilateral or contralateral limb. Conclusion: Significant variation in the quantitation of aneurysm size occurs depending on the technique of computed tomography assessment used. In most patients diameter assessment is adequate, although volumetric analysis appears to be very helpful in certain patients who do not show aneurysm regression, or in whom the diameter increases or where endoleaks persist. Three-dimensional reconstruction and volumetric analysis are also useful to assess the mechanism by which the endovascular device accommodates to morphology changes and to determine criteria for reintervention. (J Vasc Surg 2001;33:S1-10.)

Purpose: To describe the endovascular exclusion of leaking thoracic aortic aneurysms (TAA). Case Report: Two elderly patients with leaking TAAs who were at high risk for surgical intervention were transferred to our institution for possible endovascular treatment. Both patients underwent successful endovascular exclusion of the leaking TAAs using multiple stacked AneuRx thoracic endoprostheses. One patient remains alive and well at 1 year with an excluded aneurysm; the other patient died from heart failure 2 months after endografting. Conclusions: While the early results of the endovascular exclusion of leaking TAAs are promising, the use of thoracic endoprostheses remains investigational.