The inside-out technique for tunneled dialysis catheter placement with central venous occlusion.

The "inside-out" technique eliminates the need for subclavian or femoral catheter placement by placing a supraclavicular catheter via a percutaneous femoral vein access. Few reports of its use in vascular surgery exist. The purpose of this article is to describe our version of the technique and report results. Between 2016 and 2017, the inside-out technique was performed on eight patients. All patients had more than four prior access sites and bilateral internal jugular vein occlusion. The technical success rates were 100% with no periprocedural complications and success in achieving dialysis access. One patient required catheter replacement within 48 hours, one catheter was used as a bridge to Hemodialysis Reliable Outflow (Hemosphere, a Cryolife Inc Company, Eden Prairie, Minn) graft placement, and one patient died of sepsis unrelated to their catheter. Our data show the inside-out technique to be safe and effective, removes the need for subclavian or femoral catheter placement, and should be a component of treatment algorithms for complex dialysis patients, which is consistent with National Kidney Foundation's Kidney Disease Outcomes Quality Initiative recommendations.

Outcomes of vascular access for hemodialysis: A systematic review and meta-analysis.

BACKGROUND: The decision about the type and location of a hemodialysis vascular access is challenging and can be affected by multiple factors. We explored the effect of several a priori chosen patient characteristics on access outcomes. METHODS: We searched MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus through November 13, 2014. We included studies that evaluated patency, mortality, access infection, and maturation of vascular access in adults requiring long-term dialysis. Pairs of reviewers working independently selected the studies and extracted the data. Outcomes were pooled across studies using the random-effects model. RESULTS: Two hundred studies met the eligibility criteria reporting on 875,269 vascular accesses. Overall, studies appeared to have provided incidence rates at low to moderate risk of bias. The overall primary patency at 2 years was higher for fistulas than for grafts and catheters (55%, 40%, and 50%, respectively). Patency was lower in individuals with diabetes, coronary artery disease, older individuals, and in women. Mortality at 2 years was highest with catheters, followed by grafts then fistulas (26%, 17%, and 15%, respectively). CONCLUSIONS: The current evidence remains in support of autogenous access as the best approach when feasible. We provide incidence rates in various subgroups to inform shared decision making and facilitate the conversation with patients about access planning.

Impact of sarcopenia on long-term mortality following endovascular aneurysm repair.

Sarcopenia, also known as a reduction of skeletal muscle mass, is a patient-specific risk factor for vascular and cancer patients. However, there are no data on abdominal aortic aneurysm (AAA) patients treated with endovascular aneurysm repair (EVAR) who have sarcopenia. To determine the impact of sarcopenia on mortality following EVAR, we retrospectively reviewed 200 patients treated with EVAR by estimating muscle mass on abdominal computed tomography (CT) scans. Mortality was analyzed according to its presence (n=25) or absence (n=175). Sarcopenia was more common in women than men (32.0% vs 9.7%; p=0.005). Patients with sarcopenia had an increased risk of mortality compared to those without (76% vs 48%; p=0.016). Of note, the overall mortality rate was 51% with a median follow up of 8.4 years (interquartile range, 5.3-11.7). In conclusion, the presence of sarcopenia on a CT scan is an important predictor of long-term mortality in patients treated for AAA with EVAR. Pending further study, these data suggest that sarcopenia may aid in pre-procedural long-term survival assessment of patients undergoing EVAR.

Fistulas in octogenarians: are they beneficial?

BACKGROUND: The incidence of end-stage renal disease is increasing most rapidly in patients aged older than 75 years. Meanwhile, their 5-year survival rate remains the lowest of any dialysis cohort. The purpose of this study was to evaluate the benefit of arteriovenous fistula (AVF) construction in octogenarians, as the data regarding the effects of age on fistula success are conflicting. METHODS: Using our hemodialysis database, we performed a retrospective review of all AVFs placed between 1 November, 2007, and 17 July, 2013, in patients aged 80 years or older. Patient demographics, presence of catheters, time to first fistula use, fistula interventions, fistula patency, and time to patient death were all evaluated. RESULTS: We placed 32 fistulas in 31 patients. Our average patient was 82-year-old, men (75%) and Caucasian (71%). Three patients were excluded, as they never required dialysis. One patient required 2 fistulas; the second fistula was excluded from analysis. Of the remaining 28 patients, 22 (78%) were used for hemodialysis and 19 (68%) required catheter-based dialysis before fistula use. The mean length of catheter use was 166 days, and the median time to first fistula use was 109 days. Primary functional patency was 51% at year 1 and 38% at year 2, respectively. Secondary patency was 75% at year 1 and year 2. Of the 22 patients, 17 (77%) required intervention to achieve or maintain patency. The median time to death was 26 months. CONCLUSIONS: With substantial effort, successful fistula utilization can be achieved in an extremely elderly patient population. Our patients experienced significant catheter utilization and over 3 quarters required secondary interventions to achieve or maintain fistula utilization. Given this group's limited survival and the fact that 21% of their survival time was spent dialyzing with a catheter, the benefit of a functioning fistula to a patient older than 80 years can be questioned.

An early validation of the Society for Vascular Surgery lower extremity threatened limb classification system.

OBJECTIVE: The Society for Vascular Surgery (SVS) recently established the Lower Extremity Threatened Limb Classification System, a staging system using Wound characteristic, Ischemia, and foot Infection (WIfI) to stratify the risk for limb amputation at 1 year. Although intuitive in nature, this new system has not been validated. The purpose of the following study was to determine whether the WIfI system is predictive of limb amputation and wound healing. METHODS: Between 2007 and 2010, we prospectively obtained data related to wound characteristics, extent of infection, and degree of postrevascularization ischemia in 139 patients with foot wounds who presented for lower extremity revascularization (158 revascularization procedures). After adapting those data to the WIfI classifications, we analyzed the influence of wound characteristics, extent of infection, and degree of ischemia on time to wound healing; empirical Kaplan-Meier survival curves were compared with theoretical outcomes predicted by WIfI expert consensus opinion. RESULTS: Of the 158 foot wounds, 125 (79%) healed. The median time to wound healing was 2.7 months (range, 1-18 months). Factors associated with wound healing included presence of diabetes mellitus (P = .013), wound location (P = .049), wound size (P = .007), wound depth (P = .004), and degree of ischemia (P < .001). The WIfI clinical stage was predictive of 1-year limb amputation (stage 1, 3%; stage 2, 10%; stage 3, 23%; stage 4, 40%) and wound nonhealing (stage 1, 8%; stage 2, 10%; stage 3, 23%; stage 4, 40%) and correlated with the theoretical outcome estimated by the SVS expert panel. CONCLUSIONS: The theoretical framework for risk stratification among patients with critical limb ischemia provided by the SVS expert panel appears valid. Further validation of the WIfI classification system with multicenter data is justified.

Platform technologies for decellularization, tunic-specific cell seeding, and in vitro conditioning of extended length, small diameter vascular grafts.

The aim of this study was to generate extended length, small diameter vascular scaffolds that could serve as potential grafts for treatment of acute ischemia. Biological tissues are considered excellent scaffolds, which exhibit adequate biological, mechanical, and handling properties; however, they tend to degenerate, dilate, and calcify after implantation. We hypothesized that chemically stabilized acellular arteries would be ideal scaffolds for development of vascular grafts for peripheral surgery applications. Based on promising historical data from our laboratory and others, we chose to decellularize bovine mammary and femoral arteries and test them as scaffolds for vascular grafting. Decellularization of such long structures required development of a novel "bioprocessing" system and a sequence of detergents and enzymes that generated completely acellular, galactose-(α1,3)-galactose (α-Gal) xenoantigen-free scaffolds with preserved collagen, elastin, and basement membrane components. Acellular arteries exhibited excellent mechanical properties, including burst pressure, suture holding strength, and elastic recoil. To reduce elastin degeneration, we treated the scaffolds with penta-galloyl glucose and then revitalized them in vitro using a tunic-specific cell approach. A novel atraumatic endothelialization protocol using an external stent was also developed for the long grafts and cell-seeded constructs were conditioned in a flow bioreactor. Both decellularization and revitalization are feasible but cell retention in vitro continues to pose challenges. These studies support further efforts toward clinical use of small diameter acellular arteries as vascular grafts.

Radiation safety education in vascular surgery training.

OBJECTIVE: Endovascular volume during vascular surgery training has increased profoundly over recent decades, providing heavy exposure to ionizing radiation. The study purpose was to examine the radiation safety training and practices of current vascular surgery trainees. METHODS: An anonymous survey was distributed to all current U.S. trainees. Responses were compared according to the presence of formal radiation safety training and also the trainees' perception of their attendings' adherence to As Low As Reasonably Achievable (ALARA) strategies. RESULTS: The response rate was 14%. Forty-five percent had no formal radiation safety training, 74% were unaware of the radiation safety policy for pregnant females, 48% did not know their radiation safety officer's contact information, and 43% were unaware of the yearly acceptable levels of radiation exposure. Trained residents knew more basic radiation safety information, and more likely wore their dosimeter badges (P < .05). Trained residents found their radiation safety officer helpful in developing safety habits; untrained residents relied on other residents (P < .05). Trainees who felt their attendings consistently practiced ALARA strategies more likely practiced ALARA themselves (P < .05). CONCLUSIONS: The lack of formal radiation safety training in respondents may reflect an inadequate state of radiation safety education and practices among U.S. vascular surgery residents.

The influence of a Vascular Surgery Hospitalist program on physician and patient satisfaction, resident education, and resource utilization.

A number of surgery practice models have been developed to address general and trauma surgeon workforce shortages and on-call issues and to improve surgeon satisfaction. These include the creation of acute or urgent care surgery services and "surgical hospitalist" programs. To date, no practice models corresponding to those developed for general and trauma surgeons have been proposed to address these same issues among vascular surgeons or other surgical subspecialists. In 2003, our practice established a Vascular Surgery Hospitalist program. Since its inception nearly a decade ago, it has undergone several modifications. We reviewed hospital administrative databases and surveys of faculty, residents, and patients to evaluate the program's impact. Benefits of the Vascular Surgery Hospitalist program include improved surgeon satisfaction, resource utilization, timeliness of patient care, communication among referring physicians and ancillary staff, and resident teaching/supervision. Elements of this program may be applicable to a variety of surgical subspecialty settings.

Bariatric surgery is associated with a reduction in major macrovascular and microvascular complications in moderately to severely obese patients with type 2 diabetes mellitus.

BACKGROUND: Bariatric surgery (BAR) has been established as an effective treatment for type 2 diabetes mellitus (T2DM) in obese patients. However, few studies have examined the mid- to long-term outcomes of bariatric surgery in diabetic populations. Specifically, no comparative studies have broadly examined major macrovascular and microvascular complications in bariatric surgical patients vs similar, nonbariatric surgery controls. STUDY DESIGN: We conducted a large, population-based, retrospective cohort study of adult obese patients with T2DM, from 1996 to 2009, using UB-04 administrative data and vital records. Eligible patients undergoing bariatric surgery (BAR [n = 2,580]) were compared with nonbariatric surgery controls (CON [n = 13,371]) for the outcomes of any first major macrovascular event (myocardial infarction, stroke, or all-cause death) or microvascular event (new diagnosis of blindness, laser eye or retinal surgery, nontraumatic amputation, or creation of permanent arteriovenous access for hemodialysis), assessed in combination and separately, as well as other vascular events (carotid, coronary or lower extremity revascularization or new diagnosis of congestive heart failure or angina pectoris). RESULTS: Bariatric surgery was associated with favorable unadjusted 5-year event-free survival estimates for the combined primary outcome (95% ± 1% vs 81% ± 1%, log-rank p < 0.01) and each secondary outcome (log-rank p < 0.01). Multivariate-adjusted and propensity-based relative risk estimates showed BAR to be associated with a 60% to 70% reduction (adjusted hazard ratio [HR] 0.36, 95% CI 0.27 to 0.47) in the combined primary outcome and 60% to 80% risk reductions for each secondary outcome (macrovascular events [adjusted HR 0.39, 95% CI 0.29 to 0.51]; microvascular events [adjusted HR 0.22, 95% CI 0.09 to 0.49]; and other vascular events [adjusted HR 0.25, 95% CI 0.19 to 0.32]). CONCLUSIONS: Bariatric surgery is associated with a 65% reduction in major macrovascular and microvascular events in moderately and severely obese patients with T2DM.

The management of malfunctioning prosthetic arteriovenous accesses by interventional nephrologists and surgeons: a retrospective comparison of long-term outcomes.

PURPOSE: To compare the outcomes of arteriovenous grafts (AVG) managed by interventional nephrologists (IN) to those managed by vascular surgeons (VS). METHODS: Between January 2004 and February 2005, 106 forearm loop AVG were placed. Ten AVG did not meet inclusion criteria and thus were excluded from study. Forty-seven AVG were managed by IN using percutaneous interventional techniques. Vascular surgeons, using surgical techniques, cared for 49 AVG. High-risk AVG in the IN group were surveyed with fistulagrams, whereas AVG in the VS group were not. Outcomes of the IN and VS groups were retrospectively compared. RESULTS: The secondary patency rates at 6 and 18 months were 84% and 69% in the IN group and 79% and 68% in the VS group, respectively (P=.38). Twenty-five (53%) AVG in the IN required at least one surgical procedure to achieve a patency equivalent to that of the VS group. The mean number of AVG interventions to final failure was 4.8 in the IN group and 3.0 in the VS group (P=.03). Infection requiring AVG removal occurred in six patients in the IN group and one patient in the VS group (P=.07). CONCLUSIONS: Surveillance fistulagrams and percutaneous intervention for malfunctioning AVG by IN do not provide superior patency and may require more interventions over the "life" of the graft when compared to no surveillance and surgical intervention by VS. In order to achieve optimal vascular access outcomes, a collaborative relationship between nephrologist and surgeon is essential so as to ensure that the most appropriate intervention is selected and futile interventions are avoided.

A randomized prospective multicenter trial of a novel vascular sealant.

BACKGROUND: Increasing use of anticoagulant medications, particularly antiplatelet therapies, can increase the difficulty in obtaining adequate suture line hemostasis. Multiple vascular sealants have been used as adjuncts to surgical procedures, but none of them have been universally successful. The aim of this study was to evaluate the safety and effectiveness of a new prophylactic vascular sealant in arterial surgery. METHODS: A randomized prospective multi-institutional trial was undertaken comparing ArterX Vascular Sealant (AVS) with Gelfoam Plus during open arterial reconstruction. RESULTS: Three hundred thirty-one anastomotic sites in 217 patients were randomized. One hundred one of 167 (60.5%) anastomotic sites in the AVS group achieved immediate hemostasis compared with 65 of 164 (39.6%) in the control group (P = 0.001). In anastomoses with polytetrafluoroethylene grafts, 105 of 167 (62.5%) in the AVS group achieved immediate hemostasis compared with 56 of 164 (34.0%) in the control group (P < 0.001). No significant differences were noted in morbidity or mortality. Operative time was significantly less in the AVS group compared with the control group (3.2 vs. 3.8 hours, P < 0.01). CONCLUSION: Use of AVS results in superior hemostatic effectiveness compared with Gelfoam Plus, with no difference in safety. Although no cost analysis was performed, cost savings likely resulted from significantly decreased operative time.

Description and outcomes of a simple surgical technique to treat thrombosed autogenous accesses.

OBJECTIVE: Owing to the difficulty of removing acute and chronic thrombus from autogenous accesses (AA) by standard surgical and endovascular techniques, many surgeons consider efforts to salvage a thrombosed AA as being futile. We describe a simple technique to extract acute and chronic thrombus from a failed AA. This technique involves making an incision adjacent to the anastomosis, directly extracting the arterial plug, and manually milking thrombus from the access. This report details the outcomes of a series of thrombosed AAs treated by surgical thrombectomy/intervention using this technique for manual clot extraction. METHODS: A total of 146 surgical thrombectomies/interventions were performed in 102 patients to salvage a thrombosed AA. Mean follow-up was 15.6 months. Office, hospital, and dialysis unit records were reviewed to identify patient demographics, define procedure type, and determine functional patency rates. Kaplan-Meier survival analysis was used to estimate primary and secondary functional patency rates. RESULTS: Complete extraction of thrombus from the AA was achieved in 140 of 146 cases (95%). The studied procedure itself was technically successful in 127 cases (87%). Reasons for failure were the inability to completely extract thrombus from the AA in six, failed angioplasty due to long segment vein stenosis or sclerosis in seven or vein rupture in two, and central vein occlusion in one. Three failures occurred for unknown causes ≤ 3 days of successful thrombectomy. No single factor analyzed (age, sex, race, diabetes status, access type or location) was associated with technical failure. The estimated primary and secondary functional patency rates were 27% ± 5% and 61% ± 6% at 12 months. CONCLUSIONS: The manual clot extraction technique described in this report effectively removed acute and chronic thrombus from failed AAs. Its use, combined with an intervention to treat the underlying cause for AA failure, significantly extended access durability.

Role of prosthetic hemodialysis access following introduction of the dialysis outcome quality and Fistula First Breakthrough Initiatives.

The emphasis on increasing the use of autogenous hemodialysis access in the United States has clearly changed the practice pattern of vascular surgeons during the past decade. However, this change has also been associated with an increased use of cuffed dialysis catheter and a decrease in the autogenous access maturation rate. Future efforts to increase autogenous access use will be hampered, in part, by the characteristics and comorbidities of the aging hemodialysis population and system-wide health care delivery issues, such as late referral for vascular access. As a result, prosthetic access will continue to play an important role in providing vascular access for the US hemodialysis population. This article reviews contemporary trends and evidence-based literature related to autogenous and prosthetic access procedures, as well as factors that influence access choice.

The value of a carotid duplex surveillance program for stroke prevention.

BACKGROUND: Although duplex ultrasonography (DU) can readily identify progression of carotid stenosis, controversy regarding the natural history of asymptomatic carotid stenosis as well as the need and appropriate interval for carotid DU surveillance still exists. Furthermore, consensus has not yet been made in the surgical literature regarding the usefulness, cost-effectiveness, or timing of DU surveillance after carotid endarterectomy (CEA). The purpose of this study was to determine how often DU surveillance for asymptomatic carotid disease or postintervention stenosis resulted in any change in the patient's clinical management, how many strokes were prevented by DU surveillance, and the cost of such a DU surveillance program per stroke prevented. METHODS: We reviewed a 9-year vascular surgical database to identify all patients enrolled in a carotid DU surveillance program for asymptomatic carotid stenosis or following CEA between January 1, 2000, and December 31, 2008. The number of duplex scans and CEAs performed in those patients through March 2010 was also determined. The results of the Asymptomatic Carotid Atherosclerosis Study were then used to estimate the number of strokes prevented by CEA in the study population. Reimbursement data were assessed to calculate the average cost of each DU and the cost of the DU surveillance program for each stroke prevented. RESULTS: During the study period, there were 11,531 carotid duplex scans performed on 3,003 patients (mean: 3.84 scans per patient) who had been enrolled in the DU surveillance program. CEA for asymptomatic carotid stenosis was performed on 225 (7.5%) patients. The DU surveillance program prevented approximately 13 strokes (871 carotid duplex scans per stroke prevented). The mean cost of each duplex scan was $332 ± 170. The total cost of the DU surveillance program was approximately $3,830,000 or $290,000 per stroke prevented. CONCLUSIONS: Although a carotid DU surveillance program generates substantial revenue for a vascular surgery practice, it is costly and inefficient. A reappraisal of the "value" of carotid DU surveillance in stroke prevention is warranted. Consideration should be given to eliminating routine surveillance of postendarterectomy carotids in the absence of contralateral disease and limiting the number of DU surveillance studies for asymptomatic carotid disease.

Contemporary management of diabetic neuropathic foot ulceration: a study of 917 consecutively treated limbs.

BACKGROUND: For patients with diabetic neuropathic foot ulceration, the current treatment paradigm is heavily weighted toward limb revascularization; aligning incentives to perform more surgery and less ulcer management/prevention. Our purpose was to perform an analysis of functional outcomes to assess this current treatment paradigm. STUDY DESIGN: Nine hundred and seventeen neuropathic ulcerated feet in 706 patients with diabetes were analyzed. Four hundred and sixty limbs (50.2%) had concomitant ischemia, 219 of which were revascularized (137 angioplasty and 82 open surgery). Outcomes measured included ulcer healing, survival, limb salvage, amputation-free survival, maintenance of ambulation, and independence. Independent predictors of outcomes were measured using an Extended Cox Model. RESULTS: Overall outcomes (n = 917) were: ulcer healed, n = 250 (27%; mean time to healing 33 weeks); functionally healed, n = 488 (53%; mean time to functional healing 29 weeks); 5-year limb salvage, 68%; survival, 38%; amputation-free survival, 30%; maintenance of ambulation, 64%; and maintenance of independence, 74%. There was little difference in ulcer healing rates for patients with or without ischemia (28.5% versus 26%; p = 0.4). However, ischemia was a significant marker of poor outcomes (nonischemic ulcer, ischemic ulcer revascularized, and ischemic ulcer not revascularized: 5-year limb salvage of 80%, 61%, and 51%; p < 0.001); survival (47%, 37%, and 24%; p = 0.03); amputation-free survival (37%, 28%, and 17%; p < 0.001); maintenance of ambulation (74%, 55%, and 55%; p < 0.001); and maintenance of independence (82%, 72%, and 58%; p = 0.01). Wound healing was an independent predictor of survival and amputation-free survival (survival: hazard ratio = 0.58; 95% CI,0.46-0.73; amputation-free survival: hazard ratio = 0.42; 95% CI, 0.33-0.53). CONCLUSIONS: The current treatment paradigm is associated with relatively poor healing rates and substantial late morbidity and mortality. Although revascularization is effective treatment for ischemia, it is probably overvalued when compared with the potential improvement afforded by better medical foot wound management.

The impact of isolated tibial disease on outcomes in the critical limb ischemic population.

BACKGROUND: Most patients with critical limb ischemia (CLI) have multilevel infrainguinal peripheral arterial disease (M-PAD). One-third of CLI patients will have isolated tibial disease (ITD). The treatments for multilevel disease or ITD differ depending on whether open or endovascular procedures are used, but we questioned whether outcomes from these procedures differ. We evaluated outcomes of CLI patients after open and/or endovascular revascularization for CLI and assessed the impact of disease distribution. METHODS: Four hundred forty-six CLI patients (Rutherford 4-6) who underwent revascularization from 2001 to 2005 were evaluated arteriographically and followed after revascularization with noninvasive testing. Based on arteriographic data, all patients with ITD (occlusions in one or more tibial arteries) were compared with patients with occlusive femoropopliteal disease with or without concomitant tibial occlusions (M-PAD). Patients with disease solely above the inguinal ligament were excluded. Clinical data (survival, amputation-free survival, primary patency, secondary patency, limb salvage, maintenance of ambulation, and maintenance of living status) were acquired from a prospective vascular database, allowing the comparison of revascularization outcomes according to disease distribution. RESULTS: In this study, 36% of patients had ITD and 64% presented with M-PAD. The severity of ischemia at presentation was rest pain (28.5%), ulceration (42.3%), and gangrene (29.1%). In this study, 92% presented exclusively with infrainguinal disease, and 8% presented with both suprainguinal and infrainguinal disease. Risk factors included diabetes mellitus (61.2%), smoking (61.0%), coronary artery disease (57.9%), hypertension (84.3%), hyperlipidemia (40.4%), obesity (15.5%), and chronic obstructive pulmonary disease (19.3%). In comparing the ITD and M-PAD groups, there was no difference in primary patency at 2 years. All other outcomes were statistically different out to 3 years including survival (50.4% vs. 62.6%; p=0.0026, hazard ratio [HR] 0.669); amputation-free survival (35.1% vs. 50.2%; p=0.0062; HR 0.595); limb salvage (65.2% vs. 74.4%; p=0.0062; HR 0.595); maintenance of ambulation (68.9% vs. 76.9%; p=0.0352; HR 0.644); maintenance of living status (79.0% vs. 84.8%; p=0.0403; HR 0.599); and secondary patency (66.8% vs. 74.8%; p=0.0309; HR 0.665). Multivariate analyses reveal that ITD is not an independent predictor of outcome after controlling for confounding factors, of which tissue loss and end-stage renal disease correlate most consistently with poor clinical outcomes. CONCLUSION: After revascularization for CLI, ITD carries a worse prognosis (amputation-free survival, limb salvage, survival, maintenance of ambulation, and independent living status) compared with patients with M-PAD, despite the "greater" disease burden in M-PAD patients. ITD patients are more likely to have confounding factors such as diabetes mellitus, renal disease, and worse ischemia at presentation than those with M-PAD. The recognition of ITD may be helpful in identifying high-risk patients but is not an independent risk factor for poor outcomes.

Outcome of the use of stent grafts to salvage failed arteriovenous accesses.

BACKGROUND: Since elements of the Dialysis Outcome Quality Initiative (K/DOQI) were implemented a decade ago, there has been a reduction in mortality for patients on hemodialysis. As patient longevity has increased, AV access site preservation by salvaging failed arteriovenous (AV) accesses has become increasingly important. However, efforts to salvage an AV access must be balanced against futile and expensive procedures. The Viabahn Endoprosthesis is a self-expandable stent graft (SG) that can be used to treat vein rupture or fibrotic lesions with significant elastic recoil following balloon angioplasty. The literature comprising the outcome of the use of SGs in salvaging failed AV accesses is limited. The purpose of this study is to determine the outcome of failed AV accesses treated with SGs and to identify patient or graft factors predictive of success. METHODS: The vascular access database and office, hospital, and dialysis unit records were retrospectively reviewed to identify all patients who underwent placement of an SG for the treatment of a thrombosed AV access between September 2004 and December 2007. Mean patient follow-up was 6 months. The K/DOQI goal for patency following a surgical intervention (6 months or later) was used to determine procedure success or failure. Kaplan-Meier life-table analysis was used to determine patency. Patient demographics and graft factors (location, diameter, length) were analyzed to identify predictors of success. RESULTS: Fifty-five SGs were placed in 48 patients (males, 29%; mean age, 61 years; diabetes mellitus, 47%) with a failed AV access. The indications were to treat significant elastic recoil or vein rupture following balloon angioplasty (47 patients) and to treat an AV graft seroma (1 patient). Cost for the VE ranged from $2337 to $3367 per patient. The procedure was deemed successful (patent at 6 months) in 29 + or - 7% of cases. Procedure success was not influenced by AV access location, endoprosthesis size (diameter or length), or patient demographic factors (p > 0.05). CONCLUSION: Use of the SG to salvage AV accesses falls short of the current K/DOQI clinical outcome goals for successful surgical intervention in the majority of cases. Given these results and the cost of the SG, its use is indicated in cases where AV access salvage will have an impact on long-term survival such as for patients in whom there are few options for new access placement. Further studies are needed to compare the SG to less costly options, such as angioplasty alone or angioplasty with the use of bare metal stents.

Evaluation of the diameter of the proximal descending thoracic aorta with age: implications for thoracic aortic stent grafting.

BACKGROUND: Long-term anatomical changes of the thoracic aorta which may affect long-term outcome of blunt aortic injuries treated with endovascular stent grafts are unknown. The purpose of this study was to examine the natural history of thoracic aortic diameter with progressing age. METHODS: One thousand consecutive thoracic computed tomographic scans performed for nonthoracic aortic pathology on patients aged 15-99 (mean 59.4) were examined, and thoracic aortic diameter immediately adjacent to the left subclavian artery was measured. Factors possibly influencing diameter, including age by decade of life, race, gender, history of hypertension (HTN), diabetes mellitus (DM), chronic obstructive pulmonary disease (COPD), and tobacco use, were examined. Factors were compared using Student's t-test. RESULTS: The differences in mean diameters of the thoracic aorta by gender (male=27.1 vs. female=26.0, p=0.87), race (Caucasian=26.6 vs. non-Caucasian=26.3, p=0.10), presence of HTN (yes=25.8 vs. no=24.9, p=0.36), COPD (yes=26.3 vs. no=25.4, p=0.21), DM (yes=26.1 vs. no=25.3, p=0.12), and tobacco use (yes=26.3 vs. no=25.0, p=0.18) were not significant. However, differences in mean diameter increased significantly over time with age. Patients under 40 years old had mean aortic diameters of 22.92 mm compared to 27.09 mm (p<0.001) for patients over 40. The mean aortic isthmus diameter showed an approximately 1cm increase when comparing octogenarians to teenagers. CONCLUSION: The diameter of the aortic isthmus increases substantially with age. These findings suggest that long-term surveillance is warranted for trauma patients with aortic stent grafts, to monitor the natural history and to assess for possible late complications.