Proximalization of arterial inflow for treatment of hemodialysis access-induced distal ischemia.

OBJECTIVE: Hemodialysis access-induced distal ischemia (HAIDI) is a known complication of hemodialysis (HD) access. Distal revascularization and interval ligation (DRIL) is the preferred treatment for HAIDI by many surgeons. Proximalization of arterial inflow (PAI) is a promising alternative technique that, unlike DRIL, preserves the native arterial inflow. The purpose of this study is to report our experience with PAI on a series of 64 patients. METHODS: This is a single-center, retrospective cohort study of patients with both arteriovenous (AV) fistulas and grafts who underwent PAI for HAIDI from 2017 to 2023. A 4 × 7 tapered polytetrafluoroethylene (PTFE) graft was used to connect HD access inflow to the axillary artery in the majority of cases. The primary outcome of the study is resolution of HAIDI (complete, partial, or no resolution). Secondary outcomes include functional patency (primary and secondary) and 30-day complications following PAI. RESULTS: Of the 71 patients identified to have had PAI between May 2017 to August 2023, seven were lost to follow-up. In total, 64 patients were included, with an average age of 65 years (standard deviation, 15 years), 59.4% (38/64) female, and 37.5% (24/64) African American. The study population was notable for numerous comorbid conditions including 95.3% (61/64) hypertension; 50% (32/64) coronary artery disease; 79.7% (51/64) diabetes; and 43.8% (28/64) smoking history. Following PAI intervention for HAIDI, 55 of 64 patients (85.9%) experienced complete resolution of ischemic symptoms; five of 64 patients (7.8%) had partial resolution; two of 64 patients (3.1%) had no resolution, and two of 64 patients (3.1%) had unknown resolution. Primary patency at 1, 12, and 24 months was 94%, 81%, and 71%, respectively. Secondary patency at 1, 12, and 24 months was 97%, 87%, and 84%, respectively. The 30-day complication rate was 10.9% (7/64), with five of 64 (7.8%) thromboses, one of 64 (1.6%) thrombosis and infection, and one of 64 (1.6%) upper extremity swelling secondary to central venous stenosis (resolved with angioplasty of central venous system). Failure rate due to thrombosis at 12 and 24 months was 14% (9/64) and 15.6% (10/64), respectively. CONCLUSIONS: Our study, the largest case series of PAI to date, demonstrates that PAI is a reliable option for HAIDI intervention and has comparable safety and efficacy results to DRIL, despite the use of a synthetic graft. Furthermore, PAI has the added benefit of maintaining the native arterial pathway. Further investigation of PAI is warranted as a promising alternative to DRIL for HAIDI management.

A novel technique using long segment patch angioplasty maturation to increase the maturation rate of arteriovenous fistulas.

OBJECTIVE: Given the superior patency of arteriovenous fistulas (AVFs) and the decreased risk of infection compared with arteriovenous grafts, the Kidney Disease Outcomes Quality Initiative guidelines have recommended the fistula-first approach. However, ∼20% to 60% of all fistulas will fail to mature. We have described our experience with a novel technique using bovine pericardial patch angioplasty to increase the rate of AVF maturation. METHODS: We used 2-cm × 9-cm-long or 2.5-cm × 15-cm-long segment pericardial patch angioplasty to assist in the maturation of AVFs. A single-center, retrospective cohort study was conducted of all patients who had undergone patch angioplasty maturation (PAM) for AVFs that had failed to mature. The outcomes of interest were maturation status and patency, censored by the death and last known follow-up dates. RESULTS: From March 2007 to October 2019, 139 patients had undergone PAM. Follow-up data were available for 137 of the 139 patients (98.6%), with 126 AVFs (92.0%) progressing to maturation. Of the 126 patients with AVFs that had progressed to maturity, the previous hemodialysis (HD) method was known for 88 patients (69.8%). Of these 88 patients, 70 (79.5%) had previously been receiving HD via an HD catheter. Using a Kaplan-Meier estimator censored for death and loss to follow-up, the assisted primary patency rates at 1, 2, and 3 years were 87.3%, 78.1%, and 68.0%, respectively. Of the 137 patients, 69 (54.8%) had required no additional interventions after patch angioplasty. The complications requiring intervention were stenosis (n = 45; 32.8%), thrombosis (n = 10; 7.3%), infection (n = 3; 2.2%), steal syndrome (n = 3; 2.2%), noninfected wound complications (n = 1; 0.8%), and pseudoaneurysm (n = 1; 0.8%). The average interval to intervention after patch angioplasty was 4.56 months. CONCLUSIONS: Long-segment bovine pericardial PAM can be performed safely to treat nonmaturing AVFs, with a 92.0% successful maturation rate and patency rates comparable to those for AVFs. PAM should be a consideration for patients with nonmaturing AVFs.

Proper technical procedures improved outcomes in a retrospective analysis of EVAS FORWARD IDE trial 3-year results.

OBJECTIVE: Adverse outcomes observed late in the Nellix EndoVascular Aneurysm Sealing (EVAS) System (Endologix, Inc, Irvine, Calif) investigational device exemption trial prompted refinement of the anatomic instructions for use (IFU). This study aimed to investigate the association of procedural factors during Nellix endograft deployment and patient outcomes. METHODS: We retrospectively reviewed 1-month imaging of 333 patients enrolled in the prospective, multicenter EVAS investigational device exemption trial between January 2014 and September 2016. Initial observations of those patients who met revised anatomic IFU yet still experienced late adverse events suggested that inadequate seal and low graft placement were common among these patients. Key procedural variables identified from a univariate analysis were applied to construct four cohorts stratified by procedural technical performance (technically adequate [P+] or technically inadequate [P-]) and the revised anatomic indications for use (anatomically within IFU [A+] or anatomically outside of IFU [A-]) and to compare them for aneurysm-related outcomes. A logistic regression analysis was performed to identify significant predictors of sac expansion or migration. RESULTS: Proximal and distal seal zones and low graft placement were identified by logistic regression analysis as significant predictors of sac expansion or migration. Accordingly, acquisition of ≥10-mm proximal and distal seal zones and the position of the lowest stent within 10 mm of the lowest renal artery were clinically justified as thresholds for a technically adequate procedure. Patients who did not achieve these parameters were deemed to have a technically inadequate procedure. By use of the proposed procedural adequacy criteria and established anatomic criteria, patients were stratified into four cohorts: A+/P+ (n = 77), A+/P- (n = 54), A-/P+ (n = 71), and A-/P- (n = 131). Three-year estimates of freedom from migration of 10 mm were 98.6% in A+/P+, 95.9% in A+/P-, 85.8% in A-/P+, and 80.1% in A-/P-; freedom from type IA endoleak estimates were 98.6% in A+/P+, 100% in A+/P-, 96.4% in A-/ P+, and 90.3% in A-/P- cohorts. Freedom from sac expansion and secondary intervention were 96.9% and 90.6% in A+/P+, 86.0% and 93.6% in A+/P-, 87.1% and 83.1% in A-/P+, and 80.5% and 79.8% in A-/P- groups, respectively. Two early deaths (aneurysm-related mortality) on days 4 and 12 postoperatively were reported within the A+/P- group. Kaplan-Meier estimates of freedom from all-cause mortality and aneurysm-related mortality at 3 years were similar between cohorts. CONCLUSIONS: This post hoc analysis suggests that achieving a 10-mm proximal and distal seal with adequate positioning of the endograft with respect to the renal arteries is associated with improved patient outcomes.

Refinement of anatomic indications for the Nellix System for endovascular aneurysm sealing based on 2-year outcomes from the EVAS FORWARD IDE trial.

BACKGROUND: The Nellix System (Endologix, Inc, Irvine, Calif) for endovascular aneurysm sealing (EVAS) is a novel approach to abdominal aortic aneurysm treatment and conceptually different from endovascular aneurysm repair, whereby polymer is employed to fill and actively manage the abdominal aortic aneurysm sac. One-year safety and effectiveness results of the Nellix pivotal trial demonstrated encouraging outcomes with very low morbidity and mortality and high procedural and treatment success. Two-year imaging revealed a signal of migration, leading to a field safety notification issued by the manufacturer on October 21, 2016, and a dedicated root cause analysis, resulting in refinements to the instructions for use (IFU). We report the 2-year results of the investigational device exemption pivotal trial stratified according to the new and original criteria for selection of patients. METHODS: Comprehensive engineering evaluations, statistical analyses, and clinical assessments were conducted looking at patients enrolled in the pivotal trial (N = 150), roll-in cohort (N = 29), and continued access program (N = 154). All patients in all cohorts were treated on-IFU at the time of enrollment. Logistic regression models supported the mechanism that migration with Nellix is associated with a small aortic flow lumen relative to a large aneurysm thrombus burden and large aortic neck diameters. Based on these findings, refinements to the IFU criteria were applied, excluding patients with a thrombus index (maximum aneurysm sac/maximum flow lumen diameter) >1.4, aortic neck diameter >28 mm, and aortic neck conicity (>10% diameter change along the infrarenal neck) and requiring a 10-mm distal seal zone in the iliac artery. RESULTS: Freedom from all-cause mortality at 2 years was 94%. Patient outcomes were then stratified on the refined morphologic criteria and analyzed retrospectively. Two-year freedom from composite endoleak was high among both cohorts (95% on-IFU vs 92% off-IFU). Freedom from migration was 97.7% on-IFU vs 93.2% off-IFU (P = .0125). Freedom from aneurysm enlargement was 98.1% on-IFU vs 93.5% off-IFU (P value is not available because of failure of log-rank test assumptions). Composite freedom from migration, type IA endoleak, or aneurysm expansion was 95.9% among the on-IFU cohort vs 85.1% in the off-IFU cohort (P = .0017). CONCLUSIONS: Consistent with the introduction of a novel therapy, the presentation of failure modes of EVAS over time was inevitable. Using detailed imaging as well as engineering and statistical analysis, we were able to understand risk factors for adverse events specific to EVAS and defined those patients best suited for Nellix. With this EVAS-specific approach to defining IFU, on-IFU patients were identified as those with large aneurysms with little thrombus that would be prone to type II endoleaks and sac expansion with traditional devices. When treated with Nellix, these patients were predicted to experience exceptional results, especially with regard to a low composite endoleak rate and low all-cause mortality.

A Real-World Experience Comparison of Percutaneous and Open Femoral Exposure for Endovascular Abdominal Aortic Aneurysm Repair in a Tertiary Medical Center.

OBJECTIVE: To compare the outcomes of elective percutaneous endovascular aneurysm repair (PEVAR) versus surgical cutdown endovascular aneurysm repair (SEVAR) procedures performed at a tertiary medical center from 2012 to 2015. METHODS: This is a unique study using procedure data from two vascular surgeons who performed SEVAR in almost every case versus three vascular surgeons who performed PEVAR in all cases except when considered prohibitive on account of circumferential calcification or severe occlusive disease of the common femoral artery or some other technical consideration. Medical records of patients aged 18 years or older undergoing elective PEVAR or SEVAR between January 2012 and December 2015 were reviewed. Differences in readmissions and complications between patients who received PEVAR and those who received SEVAR were assessed using Fisher's exact test. The exact Cochran-Armitage test was used to assess trends in length of stay between the PEVAR and SEVAR group. RESULTS: A total of 183 patients were analyzed. In total, 132 underwent PEVAR and 51 underwent SEVAR. A statistically significant difference was noted with regard to 30-day readmissions (2.3% vs 13.7%, P = .006) in favor of PEVAR and categorical length of stay tended to be longer in the SEVAR group ( P = .003). The 30-day complication rate was not statistically different (6.8% vs 15.7%, P = .09). CONCLUSIONS: Surgical cutdown endovascular aneurysm repair results in more readmissions, often related to groin wound complications, which lead to prolonged length of stay and expense. Patients undergoing PEVAR tend to have a shorter length of stay. Overall complication rate was similar in the two groups. We recommend PEVAR for patients with appropriate anatomy.

The disproportionate growth of office-based atherectomy.

OBJECTIVE: The purpose of this study was to evaluate the trends in procedure volume, clinical sites of care, and Medicare expenditure for peripheral vascular interventions (PVIs) for lower extremity occlusive disease since the Centers for Medicare and Medicaid Services instituted reimbursement policy changes that broadened payment for procedures performed in physician-owned office-based laboratories (OBLs). METHODS: We analyzed fee-for-service Medicare claims data from 2011 to 2014 to obtain the frequency of use of PVI by type, care setting, and physician specialty. We also assessed changes in the total Medicare cost for PVI by setting. RESULTS: There was a 60% increase in atherectomy cases among Medicare beneficiaries between 2011 and 2014. During the same period, OBLs experienced a 298% increase in atherectomy volume vs a 27% increase in hospital outpatient settings and an 11% decrease for inpatient hospital settings. In 2014, OBLs were the most common setting for atherectomy. Nonatherectomy PVIs grew more modestly at just 3% but also experienced site of care shifts. Vascular surgeons and cardiologists accounted for the majority of office-based PVIs in 2014. Total Medicare costs for PVIs increased 18% from 2011 to 2014. Hospital inpatient costs declined 1%, whereas costs for hospital outpatient PVIs increased by 41% and physician office costs increased by 258%. CONCLUSIONS: The migration of revascularization procedures for lower extremity peripheral arterial occlusive disease continues from the inpatient to the outpatient setting and especially to OBLs. Increased use of atherectomy in all segments of the lower extremity arterial system has been observed, particularly in OBLs, without substantial evidence in the literature of increased efficacy compared with standard angioplasty with or without stenting. Generous Medicare reimbursement for in-office atherectomy procedures is likely contributing to the volume shifts observed.

A Cost Analysis of Regional Versus General Anesthesia for Carotid Endarterectomy.

BACKGROUND: Medical care in the United States has evolved into a more cost-conscious value-based health care system that necessitates a comparison of costs when there are alternative interventions considered to be acceptable in the treatment of a disease. This study compares the cost differences between regional anesthesia (RA) and general anesthesia (GA) for carotid endarterectomy (CEA). METHODS: Data from 346 consecutive patients who underwent CEA between January 2012 and September 2014 were retrospectively reviewed for the type of anesthesia used, outcomes data, and cost variables. Overall hospital day costs were compared between RA and GA. Medians and interquartile ranges were compared using Wilcoxon-Mann-Whitney test. A P < 0.05 was considered statistically significant using 2-sided tests. RESULTS: Median overall costs for GA were significantly higher than median costs for RA (medians [with interquartile ranges], $10,140 [$7,158-$12,658] versus $7,122 [$5,072-$8,511], P < 0.001). Median total operative time for GA was significantly longer than median time for RA (168 [144-188] versus 134 [115-147] min, P < 0.001). Median in-hospital length of stay (LOS) for GA was significantly longer compared with RA (2.0 vs 1.2 days, P < 0.001). Patients who received GA were also more likely to be admitted to the intensive care unit. CONCLUSIONS: Decreased cost, operating room expenses, postoperative resources, and overall LOS were observed for individuals who underwent RA for CEA as compared with GA. In summary, RA is more cost-effective and should be the optimal choice when clinically appropriate.

Carotid endarterectomy under local and/or regional anesthesia has less risk of myocardial infarction compared to general anesthesia: An analysis of national surgical quality improvement program database.

Multiple studies have evaluated the effect of anesthesia type on carotid endarterectomy with inconsistent results. Our study compared 30-day postoperative myocardial infarction, stroke, and mortality between carotid endarterectomy under local or regional anesthesia and carotid endarterectomy under general anesthesia utilizing National Surgical Quality Improvement Program database. All patients listed in National Surgical Quality Improvement Program database that underwent carotid endarterectomy under general anesthesia and local or regional anesthesia from 2005 to 2011 were included with the exception of patients undergoing simultaneous carotid endarterectomy and coronary artery bypass grafting. The data revealed substantial differences between the two groups compared, and these were adjusted using multiple logistic regression. Postoperative myocardial infarction, stroke, and death at 30 days were compared between the two groups. A total of 42,265 carotid endarterectomy cases were included. A total of 37,502 (88.7%) were performed under general anesthesia and 4763 (11.3%) under local or regional anesthesia. Carotid endarterectomy under local or regional anesthesia had a significantly decreased risk of 30-day postoperative myocardial infarction when compared to carotid endarterectomy under general anesthesia (0.4% vs 0.86%, p = 0.012). No statistically significant differences were found in postoperative stroke or mortality. Carotid endarterectomy under local or regional anesthesia carries a decreased risk of postoperative myocardial infarction when compared to carotid endarterectomy under general anesthesia. Therefore, patients at risk of postoperative myocardial infarction undergoing carotid endarterectomy, consideration of local or regional anesthesia may reduce that risk.

A multicenter, randomized, controlled trial of totally percutaneous access versus open femoral exposure for endovascular aortic aneurysm repair (the PEVAR trial).

OBJECTIVE: The first multicenter randomized controlled trial was designed and conducted to assess the safety and effectiveness of totally percutaneous endovascular aortic aneurysm repair (PEVAR) with use of a 21F endovascular stent graft system and either an 8 F or 10 F suture-mediated closure system (the PEVAR trial, NCT01070069). A noninferiority trial design was chosen to compare percutaneous access with standard open femoral exposure. METHODS: Between 2010 and 2012, 20 U.S. institutions participated in a prospective, Food and Drug Administration-approved randomized trial to evaluate percutaneous femoral artery access and closure by a "preclose" technique in conjunction with endovascular abdominal aortic aneurysm repair. A total of 151 patients were allocated by a 2:1 design to percutaneous access/closure (n = 101) or open femoral exposure (n = 50 [FE]). PEVAR procedures were performed with either the 8 F Perclose ProGlide (n = 50 [PG]) or the 10 F Prostar XL (n = 51 [PS]) closure devices. All endovascular abdominal aortic aneurysm repair procedures were performed with the Endologix 21 F profile (outer diameter) sheath-based system. Patients were screened by computed tomography with three-dimensional reconstruction and independent physician review for anatomic suitability and adequate femoral artery anatomy for percutaneous access. The primary trial end point (treatment success) was defined as procedural technical success and absence of major adverse events and vascular complications at 30 days. An independent access closure substudy evaluated major access-related complications. Clinical utility and procedural outcomes, ankle-brachial index, blood laboratory analyses, and quality of life were also evaluated with continuing follow-up to 6 months. RESULTS: Baseline characteristics were similar among groups. Procedural technical success was 94% (PG), 88% (PS), and 98% (FE). One-month primary treatment success was 88% (PG), 78% (PS), and 78% (FE), demonstrating noninferiority vs FE for PG (P = .004) but not for PS (P = .102). Failure rates in the access closure substudy analyses demonstrated noninferiority of PG (6%; P = .005), but not of PS (12%; P = .100), vs FE (10%). Compared with FE, PG and PS yielded significantly shorter times to hemostasis and procedure completion and favorable trends in blood loss, groin pain, and overall quality of life. Initial noninferiority test results persist to 6 months, and no aneurysm rupture, conversion to open repair, device migration, or stent graft occlusion occurred. CONCLUSIONS: Among trained operators, PEVAR with an adjunctive preclose technique using the ProGlide closure device is safe and effective, with minimal access-related complications, and it is noninferior to standard open femoral exposure. Training, experience, and careful application of the preclose technique are of paramount importance in ensuring successful, sustainable outcomes.

Improved results in the management of ruptured abdominal aortic aneurysm may not be on the basis of endovascular aneurysm repair alone.

Recent improvement in the survival of patients presenting with a ruptured abdominal aortic aneurysm (rAAA) has been credited to endovascular aneurysm repair (EVAR). We present our clinical series in the management of rAAA from 2007 to 2011. A total of 55 consecutive patient charts were reviewed. Thirty-eight patients underwent EVAR, 17 of the 55 patients did not have favorable anatomy for EVAR. Nine of the 17 patients underwent standard open repair. Eight patients underwent a 'hybrid repair' defined as suprarenal aortic endovascular balloon control followed by open repair. Overall 30-day mortality for all 55 patients was 22%. Mortality for the patients managed by endovascular aortic aneurysm repair was 26% compared with 22% with open repair. There were no deaths in the eight patients undergoing the hybrid repair. Endovascular balloon control of the aorta followed by open rAAA repair in patients who are not candidates for rEVAR has produced good results in our experience. Improved results being reported in the management of rAAA may not be on the basis of endovascular repair alone.

Cardiac morbidity of carotid endarterectomy using regional anesthesia is similar to carotid stent angioplasty.

Carotid artery stenting (CAS) was presented by carotid revascularization endarterectomy versus stenting trial as a minimally invasive approach with less risk of postoperative myocardial infarction (MI) when compared to carotid endarterectomy (CEA). Our study aimed to compare the postoperative MI rate for CAS with CEA under general anesthesia (GA) and local anesthesia (LA). A retrospective study was conducted at our institution comparing CAS with CEA under LA and CEA under GA. Thirty-day postoperative MI and strokes were evaluated for the different subgroups. A total of 1127 procedures were included in the analysis: 421 CEAs under GA, 611 CEAs under LA, and 95 CAS. No significant difference in postoperative MI was encountered between CAS and CEA under LA (0.2% vs 1.1%, P = .25). The CEA under GA was found to have a statistically significant higher risk of MI compared to LA (1.2% vs 0.2%, P = .044). Our evidence suggests that CEA under LA does not have an increased risk of MI compared to CAS.

Endovascular management of acute bleeding following recent and late open abdominal aortic aneurysm repair.

Open repair of abdominal aortic aneurysm is still considered the gold standard against which endovascular repair is measured. We describe two cases of open repair complicated by bleeding where endovascular treatment proved to be life-saving.

Percutaneous access with closure devices and iliac extension limbs allows safe repair of common iliac artery aneurysm repair as an outpatient procedure.

The true benefits of endovascular therapy will be realized when treatment for common vascular conditions can be performed effectively and safely, with minimal morbidity and in a cost-effective manner. We describe three cases of common iliac artery aneurysm repair performed as an outpatient procedure without problems. This was done in a cost-effective manner and with a high degree of patient satisfaction.

Selective two-stage basilic and cephalic vein transpositions can significantly improve the rate of fistula construction.

INTRODUCTION: Modified proximal radial artery arteriovenous fistula (MPRAVF) can be used to improve the success and patency of basilic vein transposition (BVT) and cephalic vein transposition (CVT). In the present study, surgical experience with patients requiring a two-stage BVT or CVT using MPRAVF as the first stage was reviewed. METHODS: All two-stage BVTs and CVTs performed between September 2004 and October 2006 were retrospectively reviewed. The median follow-up for this cohort was 23.7 months. One-year secondary patency of all transpositions was assessed. RESULTS: Two hundred nineteen MPRAVFs were constructed. Twelve MPRAVFs failed and underwent a second procedure. Ninety-eight patients required no further procedures and their upper arm cephalic vein was matured and used for dialysis. Of 121 patients whose MPRAVFs were functioning but unusable due to their depth, 87 underwent BVT and 34 underwent CVT. The Kaplan-Meier one-year secondary patencies (± standard error) for BVTs and CVTs were 0.90±0.03 and 0.82±0.06, respectively. At one year, 87% of all transpositions remained patent. CONCLUSIONS: Use of MPRAVF as the first stage of a two-stage BVT or CVT can significantly improve the patency rate of autogenous hemodialysis access placement beyond the 66% set forth by the Fistula First guidelines.

Patients requiring dialysis are not at risk of greater complication after carotid endarterectomy.

Stroke is a leading cause of disability and the third leading cause of death. Landmark studies have demonstrated that carotid endarterectomy (CEA) reduced the risk of stroke among selected patients with carotid stenosis. Renal insufficiency is a known risk factor for stroke and appears to be an independent risk factor for poor outcome after CEA. Studies have reported high morbidity and mortality after CEA in patients on dialysis. However, our experience has been that patients undergoing dialysis have no greater risk for a poor outcome. This study was a retrospective review of our CEA patients to ascertain our morbidity and mortality results in dialysis patients versus patients not on dialysis. An institutional retrospective chart review of CEAs from January 1999 to December 2007 was conducted. Patients on dialysis at the time of CEA were identified. Their charts were reviewed for complications 30 days after surgery. This was compared with our total experience with CEAs from January 1999 to December 2007. Of the 28 patients undergoing CEA while dialysis dependent, none had complications in the 30-day postoperative period. This compares favorably with the cohort of all CEAs by the same surgeons. In that group, 13 complications were identified (13 of 1,141). Patients undergoing dialysis are at no greater risk for complications when undergoing carotid endarterectomy than the general population.

Internal iliac artery revascularization for limb salvage purposes.

Lower extremity revascularization is routinely performed for limb salvage purposes when critical limb ischemia has developed in a patient. Traditional reconstructions have been well described in the literature. We present a case of internal iliac artery endarterectomy with aortointernal iliac bypass for the treatment of limb ischemia.