Aortic Curvature Instead of Angulation Allows Improved Estimation of the True Aorto-iliac Trajectory.

OBJECTIVE: Supra- and infrarenal aortic neck angulation have been associated with complications after endovascular aortic aneurysm repair. However, a uniform angulation measurement method is lacking and the concept of angulation suggests a triangular oversimplification of the aortic anatomy. (Semi-)automated calculation of curvature along the center luminal line describes the actual trajectory of the aorta. This study proposes a methodology for calculating aortic (neck) curvature and suggests an additional method based on available tools in current workstations: curvature by digital calipers (CDC). METHODS: Proprietary custom software was developed for automatic calculation of the severity and location of the largest supra- and infrarenal curvature over the center luminal line. Twenty-four patients with severe supra- or infrarenal angulations (≥45°) and 11 patients with small to moderate angulations (<45°) were included. Both CDC and angulation were measured by two independent observers on the pre- and postoperative computed tomographic angiography scans. The relationships between actual curvature and CDC and angulation were visualized and tested with Pearson's correlation coefficient. The CDC was also fully automatically calculated with proprietary custom software. The difference between manual and automatic determination of CDC was tested with a paired Student t test. A p-value was considered significant when two-tailed α < .05. RESULTS: The correlation between actual curvature and manual CDC is strong (.586-.962) and even stronger for automatic CDC (.865-.961). The correlation between actual curvature and angulation is much lower (.410-.737). Flow direction angulation values overestimate CDC measurements by 60%, with larger variance. No significant difference was found in automatically calculated CDC values and manually measured CDC values. CONCLUSION: Curvature calculation of the aortic neck improves determination of the true aortic trajectory. Automatic calculation of the actual curvature is preferable, but measurement or calculation of the curvature by digital calipers is a valid alternative if actual curvature is not at hand.

Endovascular repair or surveillance of patients with small AAA.

OBJECTIVE: To compare the outcome of patients with small abdominal aortic aneurysms (AAA) treated in a prospective trial of endovascular aneurysm repair (EVAR) to patients randomized to the surveillance arm of the UK Small Aneurysm Trial. METHOD: All patients with small AAA (< or = 5.5 cm diameter) treated with a stent graft (EVARsmall) in the multicenter AneuRx clinical trial from 1997 to 1999 were reviewed with follow up through 2003. A subgroup of patients (EVARmatch) who met the age (60-76 years) and aneurysm size (4.0-5.5 cm diameter) inclusion criteria of the UK Small Aneurysm Trial were compared to the published results of the surveillance patient cohort (UKsurveil) of the UK Small Aneurysm Trial (NEJM 346:1445, 2002). Endpoints of comparison were aneurysm rupture, fatal aneurysm rupture, operative mortality, aneurysm related death and overall mortality. The total patient years of follow-up for EVAR patients was 1369 years and for UK patients was 3048 years. Statistical comparisons of EVARmatch and UKsurveil patients were made for rates per 100 patient years of follow up (/100 years) to adjust for differences in follow-up time. RESULTS: The EVARsmall group of 478 patients comprised 40% of the total number of patients treated during the course of the AneuRx clinical trial. The EVARmatch group of 312 patients excluded 151 patients for age < 60 or > 76 years and 15 patients for AAA diameter < 4 cm. With the exception of age, there were no significant differences between EVARsmall and EVARmatch in pre-operative factors or post-operative outcomes. In comparison to the UKsurveil group of 527 patients, the EVARmatch group was slightly older (70 +/- 4 vs. 69 +/- 4 years, p = 0.009), had larger aneurysms (5.0 +/- 0.3 vs. 4.6 +/- 0.4 cm, p < 0.001), fewer women (7 vs. 18%, p < 0.001), and had a higher prevalence of diabetes and hypertension and a lower prevalence of smoking at baseline. Ruptures occurred in 1.6% of EVARmatch patients and 5.1% of UKsurveil patients; this difference was not significant when adjusted for the difference in length of follow up. Fatal aneurysm rupture rate, adjusted for follow up time, was four times higher in UKsurveil (0.8/100 patient years) than in EVARmatch (0.2/100 patient years, p < 0.001); this difference remained significant when adjusted for difference in gender mix. Elective operative mortality rate was significantly lower in EVARmatch (1.9%) than in UKsurveil (5.9%, p < 0.01). Aneurysm-related death rate was two times higher in UKsurveil (1.6/100 patient years) than in EVARmatch (0.8/100 patient years, p = 0.03). All-cause mortality rate was significantly higher in UKsurveil (8.3/100 patient years) than in EVARmatch (6.4/100 patient years, p = 0.02). CONCLUSIONS: It appears that endovascular repair of small abdominal aortic aneurysms (4.0-5.5 cm) significantly reduces the risk of fatal aneurysm rupture and aneurysm-related death and improves overall patient survival compared to an ultrasound surveillance strategy with selective open surgical repair.

Primary endovascular repair of juxtarenal aneurysms with fenestrated endovascular grafting.

PURPOSE: To evaluate outcomes of an endovascular graft incorporating the visceral aortic segment with graft material in the setting of juxtarenal aneurysms. MATERIALS AND METHODS: A prospective analysis of patients undergoing implantation of an endovascular device with graft material proximal to the renal arteries was conducted. All patients were deemed unacceptable candidates for open surgical repair and had proximal neck length=<10 mm, or =<15 mm with a compromising morphology (funnel or thrombus). Fenestrations were customized to accommodate aortic branch anatomy based upon CT and intravascular ultrasound data. Selective visceral ostia were treated with balloon expandable stents following endograft deployment. All patients were evaluated with CT, duplex ultrasound, and abdominal radiograph at discharge, 1, 6, 12 and 24 months. RESULTS: A total of 32 patients were enrolled in the trial. Short proximal necks (3-10 mm) were present in 22, and 10 had necks 10-15 mm in length with concomitant angulation or thrombus compromising neck quality. Endograft design included bifurcated (30) and aortic tube (2) systems. A total of 83 visceral vessels were incorporated (mean of 2.6 per patient). These most commonly included both renal arteries and the SMA. All prostheses were implanted successfully without the acute loss of any visceral arteries. The mean follow-up was 9.2 months (range 0-24 months). One patient died within 30 days of device implantation and hypogastric bypass following the development of aspiration pneumonia. Three early (<30 days) and three late secondary interventions were performed. The 30-day endoleak rate was 6.5%. The aneurysm sac decreased greater than 5 mm in 58% of patients at 6 months and in 75% of patients at 12 months. One patient, with a persistent type II endoleak had 5 mm of sac growth over 12 months. Six patients had transient or permanent elevation of serum creatinine (>30% from baseline), with one requiring hemodialysis. Of the 83 vessels incorporated, three late stenoses (all successfully treated with an endovascular approach) and two renal occlusions were detected during follow-up. Three patients died of unrelated causes during the follow-up period. CONCLUSIONS: The placement of endovascular prostheses with graft material incorporating the visceral arteries is technically feasible. The incidence of endoleaks is exceptionally low. It remains critical to follow the status of stented visceral vessels, and establish the long-term efficacy of this type of repair.

Current outcomes in endovascular repair of abdominal aortic aneurysms.

The repair of abdominal aortic aneurysms has presently been reported to be accomplished using endovascular techniques in 60% of the cases. As technology continues to improve on the design of endovascular devices, this will only result in a progressive upward trend of this innovative method. At this time, there are multiple commercial and investigational devices available. We elect to discuss current results pertaining to the optimal candidate, characteristics, complications, and the long-term durability of aortic stent-grafts.

Safety and efficacy of limited-dose tissue plasminogen activator in acute vascular occlusion.

OBJECTIVE: The purposes of this study were to evaluate the safety and efficacy of limited-dose tissue plasminogen activator (t-PA) in patients with acute vascular occlusion and to compare these results with those obtained in equivalent patients receiving urokinase. METHODS: We compared the results of 60 patients receiving catheter-directed urokinase from November 1997 to November 1998 (240,000 units/h x 4 h, 120,000 units/h thereafter for a maximum of 48 h) with those of 45 patients receiving catheter-directed t-PA from November 1998 to August 2000 (2 mg/h, total dose < or =100 mg) for acute arterial occlusion (AAO) and acute venous occlusion (AVO). Interventional approaches such as cross-catheter and coaxial techniques were used to reduce the dose of lytic agent needed to achieve pre-lysis-treatment goals (eg, complete lysis of all thrombus/unmasking graft stenosis or establishing outflow target). Statistical analysis was performed using Student t test and Fisher exact test. RESULTS: The urokinase and t-PA groups were comparable with regard to age, comorbidities (coronary artery disease, hypertension, diabetes, renal insufficiency, smoking), duration of ischemic or occlusive symptoms, location of occlusive process, pretreatment with warfarin, and thrombotic versus embolic and native versus graft occlusion in patients with AAO. In patients with AAO and in those with AVO, t-PA was equivalent to or better than urokinase with regard to percent of clot lysis, incidence of major bleeding complications, limb salvage, and mortality. Achievement of pretreatment goals (arterial patients only) was 50% for urokinase patients and 76% for t-PA patients (P =.02). Analysis of success in individual pretreatment-goal achievement showed urokinase and t-PA to be equivalent in unmasking stenoses (85% and 84%, respectively; P = NS), whereas t-PA was superior to urokinase in the more critical task of establishing run-off (39% versus 81% for urokinase and t-PA, respectively; P =.001). Additional interventions, either endovascular or surgical, were required in 60% and 51% (P = NS) of patients receiving urokinase and t-PA, respectively, for AAO, and in 54% and 62% (P = NS) of patients receiving urokinase and t-PA, respectively, for AVO. CONCLUSIONS: Limited-dose t-PA is a safe and effective therapy for AAO and AVO when administered by experienced teams using innovative but well-established interventional techniques.

Peripheral artery occlusion: treatment with abciximab plus urokinase versus with urokinase alone--a randomized pilot trial (the PROMPT Study). Platelet Receptor Antibodies in Order to Manage Peripheral Artery Thrombosis.

PURPOSE: To evaluate the combination of a platelet glycoprotein IIb/IIIa complex receptor inhibitor and urokinase for treatment of recent (

Hemodynamic conditions at the carotid bifurcation during protective common carotid occlusion.

OBJECTIVES: Carotid angioplasty and stenting procedures are associated with an obligatory release of particulate debris into the distal cerebral circulation. Although most of the emboli are small and do not result in symptomatic neurologic deficits, some may be large enough to cause stroke. For this reason, a variety of filters and balloon occlusion devices have been employed as adjuvants to decrease the risk of distal embolization during carotid stenting. Some of these devices rely on the arrest of antegrade blood flow with the use of inflow arrest. The present study was undertaken to investigate the hemodynamic conditions that exist at the carotid bifurcation during common carotid artery (CCA) occlusion. METHODS: Internal carotid artery (ICA) and external carotid artery (ECA) stump pressures were measured in 29 patients undergoing carotid endarterectomy. Duplex ultrasound scanning was used to measure the direction and velocity of blood flow in the ICA and ECA with the CCA cross-clamped but the ICA and ECA open, a clinical scenario analogous to CCA balloon occlusion at the time of carotid angioplasty and stenting. The direction and magnitude of ICA and ECA flow were compared with the stump pressures to determine whether a correlation existed between these variables. RESULTS: The mean stump pressure in the ICA and ECA averaged 56 +/- 16 and 53 +/- 12 mm Hg, respectively. The ICA systolic stump pressure was lower than the ECA systolic stump pressure in six patients (21%), and all of these patients had persistent antegrade systolic duplex blood flow by duplex interrogation during CCA occlusion. The ICA systolic stump pressure exceeded the ECA systolic stump pressure in 19 patients (66%), and all of these patients had retrograde ICA flow during systole. Diastolic flow was also well correlated with the magnitude of the ICA/ECA stump pressure differential, with antegrade diastolic ICA blood flow in all nine patients with an ICA diastolic stump pressure less than the ECA diastolic stump pressure. None of the 10 patients with ICA diastolic stump pressure greater than ICA diastolic stump pressure maintained antegrade ICA diastolic flow, but four of these patients had flow to zero in diastole. Overall, 13 of 29 patients (45%) could be surmised to be at risk for distal embolization to the brain based on the persistence of some element of either systolic or diastolic antegrade ICA flow during common carotid occlusion. CONCLUSIONS: Common carotid occlusion alone appears insufficient to protect against distal embolization during manipulations of the carotid bifurcation. Persistent systolic or diastolic antegrade blood flow occurs in a high proportion of patients, lending credence to the use of additional protective strategies to ameliorate the risk of embolic complications.

Initial experience of platelet glycoprotein IIb/IIIa inhibition with abciximab during carotid stenting: a safe and effective adjunctive therapy.

BACKGROUND AND PURPOSE: Abciximab has been shown to decrease periprocedural ischemic complications after coronary intervention. However, the adjunctive use of abciximab in carotid stenting has not been adequately studied. We sought to determine the efficacy and safety of abciximab in carotid stenting. METHODS: Carotid stenting was performed in 151 consecutive patients determined to be at high surgical risk by a vascular surgeon. Of these, 128 consecutive patients received adjuvant therapy with abciximab (0.25 mg/kg bolus before the lesion was crossed with guidewire and 0.125 micro. kg(-1). min(-1) infusion for 12 hours.). A heparin bolus of 50 U/kg was given, and activated clotting time was maintained between 250 to 300 seconds. All patients received aspirin and thienopyridine. Procedural and 30-day outcomes were compared between the control (n=23) and abciximab (n=128) groups. RESULTS: The 2 groups had similar baseline characteristics. Procedural events were more frequent in the control group (8%; 1 major stroke and 1 neurological death) compared with the abciximab group (1.6%; 1 minor stroke and 1 retinal infarction; P=0.05). On 30-day follow-up, 1 patient presented with delayed intracranial hemorrhage in the abciximab group. There were no other major bleeding complications. CONCLUSIONS: Adjunctive use of abciximab for carotid stenting is safe with no increase in the risk of intracranial hemorrhage. This adjunctive therapy with potent glycoprotein IIb/IIIa inhibition may help to reduce periprocedural adverse events in patients undergoing carotid stenting.

Peripheral arterial disease.

Lower extremity peripheral arterial disease (PAD) most frequently presents with pain during ambulation, which is known as "intermittent claudication". Some relief of symptoms is possible with exercise, pharmacotherapy, and cessation of smoking. The risk of limb-loss is overshadowed by the risk of mortality from coexistent coronary artery and cerebrovascular atherosclerosis. Primary therapy should be directed at treating the generalised atherosclerotic process, managing lipids, blood sugar, and blood pressure. By contrast, the risk of limb-loss becomes substantial when there is pain at rest, ischaemic ulceration, or gangrene. Interventions such as balloon angioplasty, stenting, and surgical revascularisation should be considered in these patients with so-called "critical limb ischaemia". The choice of the intervention is dependent on the anatomy of the stenotic or occlusive lesion; percutaneous interventions are appropriate when the lesion is focal and short but longer lesions must be treated with surgical revascularisation to achieve acceptable long-term outcome.

Identification and implications of transgraft microleaks after endovascular repair of aortic aneurysms.

PURPOSE: The purpose of this report is to describe an interesting cause of endoleak and detail-specific techniques for identifying small transgraft defects, which we have termed microleaks. METHODS: Four patients underwent endovascular repair of abdominal aortic aneurysms with modular nitinol/polyester endoprostheses and were studied after 6 to 30 months. All patients were enrolled in standard follow-up radiographic surveillance protocols. RESULTS: Three of the four abdominal aortic aneurysms continued to expand after endograft repair. Standard computed tomography imaging with precontrast, dynamic contrast, and delayed imaging frequently identifies endoleak, although it fails to precisely identify microleaks as the source. Color flow duplex ultrasound scan was performed on three patients and perigraft "jets," small areas of color flow adjacent to the endograft, were identified in all. Microleaks were identified in one patient who underwent digital subtraction arteriography with directed efforts to completely opacify the prosthesis lumen and multiple oblique projections. In another patient, contrast arteriography with balloon occlusion of the distal endograft clearly depicted midgraft microleaks that might otherwise be mistaken for graft porosity or cuff junction endoleaks. No microleaks were diagnosed on angiograms when these directed efforts were not performed. Aneurysm exploration before aortic clamping provided conclusive determination of the presence of blood flow through the wall of the endoprosthesis in two patients. CONCLUSIONS: Microleaks occur up to 2.5 years after endovascular repair of aortic aneurysms. Although computed tomography demonstrates the presence of an endoleak in these patients, the exact site of origin usually remains obscure. Doppler ultrasound scan and directed arteriography appear to be of greater utility for identifying the presence and location of microleaks. Balloon occlusion arteriography and aneurysm exploration without arterial clamping provide definitive evidence of microleaks. Although the clinical significance of microleaks remains unclear, long-term monitoring of patients is imperative to diagnose and treat these and other modes of endograft failure before they progress to aneurysm rupture.

Endovascular management of visceral artery aneurysm.

PURPOSE: To retrospectively review our experience with visceral artery aneurysms (VAAs) treated with percutaneous coil embolization techniques. METHODS: Patient records were retrospectively reviewed between 1988 and 1998 for VAA cases treated with catheter-based techniques. Nine patients (5 women; mean age 64 +/- 11 years) with 12 (8 false and 4 true) VAAs were identified. The majority (67%) of these patients presented with symptoms of aneurysm rupture. The etiology of the aneurysm was iatrogenic in 4, pancreatitis in 4, and idiopathic in 4. Ten cases involved the hepatic artery; the other 2 aneurysmal arteries were the middle colic and the gastroduodenal. Selective and superselective catheter techniques were used to obtain access to the VAA. A variety of microcoils were delivered to entirely fill saccular aneurysms, whereas fusiform aneurysms were thrombosed by occluding the inflow and outflow vessels. RESULTS: Aneurysm exclusion was achieved in 9 (75%) of the 12 cases. The 3 technical failures resulted from the inability to cannulate the aneurysm neck. Coil embolization of the neck of the aneurysm sac did not result in occlusion of the native vessel, with a single exception. No procedure-related complications or deaths were noted. All patients remained symptom free during a mean follow-up of 46.0 +/- 29.6 months. CONCLUSIONS: Percutaneous transcatheter coil embolotherapy is an effective alternative to open surgery for the management of VAAs. This therapy may decrease the morbidity and mortality associated with an open surgical procedure in patients with ruptured aneurysms and pseudoaneurysms, selectively thrombosing the aneurysm while preserving flow in the native vessel.

Preprocedural risk stratification: identifying an appropriate population for carotid stenting.

PURPOSE: Given the uncertainties associated with carotid angioplasty and stenting, the initial assessment of the procedure may be best undertaken in a subgroup of patients at increased risk for complications with standard carotid surgery. In an effort to characterize such a subgroup, we reviewed the results of carotid endarterectomy in patients with and without significant medical comorbidity. METHODS: During a 10-year period 3061 carotid endarterectomies were performed at a single institution and entered prospectively into a registry. A high-risk patient subgroup was identified, defined by the presence of severe coronary artery disease, chronic obstructive lung disease, or renal insufficiency. The outcome of carotid endarterectomy was assessed with respect to perioperative stroke, myocardial infarction, or death, as well as the combined end point of one or more of the end points. RESULTS: The rate of the composite end point stroke/myocardial infarction/death was 3.8% in the total group of 3061 patients who underwent endarterectomy. As individual end points, the rate of stroke was 2.1%, myocardial infarction 1.2%, and death 1.1%. Among the high-risk subset, the composite end point stroke/myocardial infarction/death occurred in 7.4%. This rate was significantly greater than the corresponding rate of 2.9% in the low-risk subset (P <.0005). Similarly, the rate of stroke (3.5% vs 1.7%, P =.008) or death (4.4% vs 0.3%, P <.001) as solitary events was significantly greater in high-risk patients. CONCLUSIONS: Although carotid endarterectomy is an extremely safe procedure in most patients, results are not as favorable in a high-risk subset with severe coronary, pulmonary, or renal disease. The initial clinical evaluation of carotid stenting might best be undertaken in such a high-risk population, one that comprises patients for whom standard therapy is associated with a high rate of complications.

The use of mechanical thrombectomy devices in the management of acute peripheral arterial occlusive disease.

A number of percutaneous mechanical thrombectomy devices are currently being used or undergoing clinical evaluation for the treatment of acute and chronic limb-threatening ischemia. Preliminary studies on the safety, efficacy, and device limitations have spurred an interest in percutaneous techniques for thrombus debulking as stand-alone therapy or an adjunct to pharmacologic thrombolysis. The devices have various mechanisms or combinations of mechanisms to optimize thrombus removal. Efficacy of thrombus removal is balanced by the propensity for vessel wall damage and distal embolization, especially for wall-contact devices (Arrow-Trerotola device and Cragg and Castañeda brushes). Initial experience in hemodialysis graft occlusion has subsequently moved on to peripheral arterial occlusions. Although the U.S. Food and Drug Administration has approved eight mechanical thrombectomy devices (MTDs) for use in thrombosed hemodialysis grafts, only the AngioJet LF140 is currently approved for use in peripheral arterial occlusive disease. Nevertheless, numerous clinical articles and abstracts have reported the "off-label" use of MTDs in the management of limb-threatening ischemia. A description of the eight MTDs and a review of the current literature on use of MTDs for acute peripheral arterial occlusive disease are provided.

Rheolytic thrombectomy in the management of acute and subacute limb-threatening ischemia.

PURPOSE: To evaluate the use of a percutaneous mechanical thrombectomy (PMT) catheter (AngioJet) as an initial treatment for acute (<2 weeks) and subacute (2 weeks to 4 months) arterial occlusion of the limbs. MATERIALS AND METHODS: A total of 86 (acute, n = 65; subacute, n = 21) patients were available for retrospective analysis, averaging 65 +/- 14 years of age. Outcomes assessed include initial angiographic success (failure = less than 50% luminal restoration [LR]; partial success = 50%-95% LR; success = more than 95% LR), pre- and postprocedural ankle-brachial index (ABI), device-related and systemic complications, 1-month amputation, mortality, and short-term patency. RESULTS: Angiographic success was evaluated in 83 of 86 patients (guide wire unable to traverse lesion in three patients). The procedure failed in 13 of 83 (15.6%) patients, partial success was seen in 19 of 83 patients (22.9%), and successful recanalization was noted in 51 of 83 patients (61.4%). Adjunctive thrombolysis was used in 50 of 86 patients (58%). However, thrombolysis resulted in angiographic improvement at the site of PMT in only seven of 50 of these patients (14%). Adjunctive thrombolysis was uniformly unsuccessful in patients in whom initial PMT failed. The median increase in ABI was 0.64 (95% CI: 0.43-0.81). Success was more likely in the setting of in situ thrombosis, with 61 of 68 (90%) procedures successful, compared to embolic occlusions, with nine of 15 (60%) procedures successful (P =.011). Angiographic outcome was not dependent on the duration of occlusion (acute, 51 of 62; subacute, 19 of 21; P =.35) or the conduit type (graft, 28 of 31; native vessel, 42 of 52; P =.35). An underlying stenosis was identified in 53 of the 70 patients (75.7%) with a successful PMT, and 51 of these 53 unmasked lesions were successfully treated. Follow-up data were available in 56 patients for patency assessment at a median of 3.9 months (range, 0.1-28.5 months). Patency at 6 months was 79% (95% CI: 65-92). Systemic complications occurred in 16.3% of patients, local complications were noted in 18.6%, and 1-month amputation and mortality rates were 11.6% and 9.3%, respectively. CONCLUSION: PMT offers the potential to rapidly reestablish flow to an ischemic extremity and may be the only available treatment option in patients at high risk for open surgery or with contraindications to pharmacologic thrombolysis.

Percutaneous AngioJet thrombectomy in the management of extensive deep venous thrombosis.

PURPOSE: This study was undertaken to evaluate the efficacy of a percutaneous mechanical thrombectomy (PMT) device for rapid thrombus removal following deep venous thrombosis (DVT). MATERIALS AND METHODS: Over a 37-month period, 17 patients (14 women; mean age, 41 y +/- 20) with extensive DVT were treated with initial attempts at PMT with use of the AngioJet rheolytic thrombectomy device. Sites of venous thrombosis included lower extremities in 14 patients and upper extremity and brachiocephalic veins in three. The etiology for venous thrombosis was malignancy in seven, idiopathic etiology in three, May-Thurner syndrome and immobilization in three each, and oral contraceptive use and hypercoagulable disorder in one each. The primary endpoint was venographic evidence of thrombus extraction. Perioperative complications, mortality, and recurrence-free survival were also evaluated. RESULTS: After PMT, four of 17 patients (24%) had venographic evidence of >90% thrombus removal, six of 17 (35%) had 50%-90% thrombus removal, and seven of 17 (41%) had <50% thrombus extraction. Adjunctive thrombolytic therapy was used in nine of 13 patients with <90% thrombus extraction by PMT; six patients (35%) had contraindications to pharmacologic thrombolytic therapy. An underlying lesion responsible for the occlusion was uncovered in 10 patients (59%). Significant improvement in clinical symptoms was seen in 14 of 17 patients (82%). No complications were noted directly relating to the use of the AngioJet thrombectomy catheter. None of the patients were lost to follow-up during a mean of 8.9 months +/- 5.3 (range, 2-21 months). At 4 and 11 months, recurrence-free survival rates were 81.6% and 51.8%, respectively. CONCLUSION: PMT with adjunctive thrombolytic therapy is a minimally invasive, low-risk therapeutic option in patients with extensive DVT, associated with clinical benefits including thrombus removal, patency, and relief of symptoms.

An update of the Zenith endovascular graft for abdominal aortic aneurysms: initial implantation and mid-term follow-up data.

PURPOSE: To evaluate the initial and mid-term results of the Zenith endovascular grafting system for infrarenal abdominal aortic aneurysms. METHODS: Prospective databases at seven centers were used to assess a cohort of patients that underwent treatment for aortic, aortoiliac, or iliac aneurysms since 1995. Data were analyzed to yield descriptive characteristics that pertained to the patients, the aortic morphologic features, the graft configuration, and the complications. Follow-up imaging data were used to determine size changes of the aneurysm sac, endoleak rates, and further complications. Finally survival data were expressed with a Kaplan-Meier analysis. RESULTS: A total of 528 patients were treated with the Zenith endograft. Most of the patients (66%) were considered to be at a high physiologic risk for open repair. Successful graft implantation was accomplished in all but four patients. An overall endoleak rate of 15% was noted, of which 4% was treated urgently because they were thought to represent attachment site faults. The mean follow-up period was 18 months. A total of eight endograft migrations were detected after 2 years of follow-up with an early version of the system. There were three late conversions; two ruptures occurred during the follow-up period. CONCLUSION: This early and mid-term data support the use of the Zenith endovascular graft for the treatment of aortic and aortoiliac aneurysms in properly selected patients. The risks of significant complications or aneurysm rupture are low.