One-year limb salvage and quality of life following mechanical aspiration thrombectomy in patients with acute lower extremity ischemia.

OBJECTIVE: Lower extremity acute limb ischemia (LE-ALI) is associated with high morbidity and mortality rates, and a burden on patient quality of life (QoL). There is limited medium- to long-term evidence on mechanical aspiration thrombectomy (MT) in patients with LE-ALI. The STRIDE study was designed to assess safety and efficacy of MT using the Indigo Aspiration System in patients with LE-ALI. Thirty-day primary and secondary endpoints and additional outcomes were previously published. Here, we report 365-day secondary endpoints and QoL data from STRIDE. METHODS: STRIDE was a multicenter, prospective, single-arm, observational cohort study that enrolled 119 patients across 16 sites in the United States and Europe. Patients were treated first-line with MT using the Indigo Aspiration System (Penumbra, Inc). The study completed follow-up in October 2023. Secondary endpoints at 365 days included target limb salvage and mortality. Additionally, the VascuQoL-6 questionnaire, developed for evaluating patient-centered QoL outcomes for peripheral arterial disease, was assessed at baseline and follow-up through 365 days. RESULTS: Seventy-three percent of patients (87/119) were available for 365-day follow-up. Mean age of these patients was 65.0 ± 13.3 years, and 44.8% were female. Baseline ischemic severity was classified as Rutherford I in 12.6%, Rutherford IIa in 51.7%, and Rutherford IIb in 35.6%. In general, baseline and disease characteristics (demographics, medical history, comorbidities, target thrombus) of these patients are similar to the enrolled cohort of 119 patients. The secondary endpoints at 365 days for target limb salvage was 88.5% (77/87) and mortality rate was 12.0% (12/100). VascuQoL-6 improved across all domains, with a median total score improvement from 12.0 (interquartile range, 9.0-15.0) at baseline to 19.0 (interquartile range, 16.0-22.0) at 365 days. CONCLUSIONS: These 365-day results from STRIDE demonstrate that first-line MT with the Indigo Aspiration System for LE-ALI portray continued high target limb salvage rates and improved patient-reported QoL. These findings indicate Indigo as a safe and effective therapeutic option for LE-ALI.

Safety and efficacy of mechanical aspiration thrombectomy for patients with acute lower extremity ischemia.

OBJECTIVE: Acute limb ischemia (ALI) is associated with high rates of amputation and consequent morbidity and mortality. The objective of this study is to report on the safety and efficacy of aspiration thrombectomy using the Indigo Aspiration System in patients with lower extremity (LE) ALI. METHODS: The STRIDE study was an international, multicenter, prospective, study that enrolled 119 participants presenting with LE-ALI. Patients were treated firstline with mechanical thrombectomy using the Indigo Aspiration System, before stenting or angioplasty, or other therapies as determined by treating physician. The primary end point was target limb salvage at 30 days after the procedure. Secondary end points within 30 days included technical success, defined as core laboratory-adjudicated Thrombolysis in Myocardial Infarction (TIMI) 2/3 flow rate immediately after the procedure, changes in modified Society for Vascular Surgery runoff score, improvement of Rutherford classification compared with before the procedure, patency, rate of device-related serious adverse events, and major periprocedural bleeding. Secondary end points that will be evaluated at 12 months include target limb salvage and mortality. RESULTS: Of the 119 participants enrolled at 16 sites, the mean age was 66.3 years (46.2% female). At baseline (n = 119), ischemic severity was classified as Rutherford I in 10.9%, Rutherford IIa in 54.6%, and Rutherford IIb in 34.5%. The mean target thrombus length was 125.7 ± 124.7 mm. Before the procedure, 93.0% (of patients 107/115) had no flow (TIMI 0) through the target lesion. The target limb salvage rate at 30 days was 98.2% (109/111). The rate of periprocedural major bleed was 4.2% (5/119) and device-related serious adverse events was 0.8% (1/119). Restoration of flow (TIMI 2/3) was achieved in 96.3% of patients (105/109) immediately after the procedure. The median improvement in the modified Society for Vascular Surgery runoff score (before vs after the procedure) was 6.0 (interquartile range, 0.0-11.0). Rutherford classifications also improved after discharge in 86.5% of patients (83/96), as compared with preprocedural scores. Patency at 30 days was achieved in 89.4% of patients (101/113). CONCLUSIONS: In the STRIDE (A Study of Patients with Lower Extremity Acute Limb Ischemia to Remove Thrombus with the Indigo Aspiration System) study, aspiration thrombectomy with the Indigo System provided a safe and effective endovascular treatment for patients with LE-ALI, resulting in a high rate (98.2%) of successful limb salvage at 30 days, with few periprocedural complications.

Prolonged lower extremity endovascular procedures for patients with claudication increase risk of adverse outcomes.

OBJECTIVE: Historically, longer operative times for open infrainguinal revascularization have been associated with higher perioperative complication rates, especially surgical site infections and extended lengths of stay. We sought to determine whether an association existed between the procedure length and morbidity or mortality after elective lower extremity endovascular interventions. METHODS: We conducted a cross-sectional retrospective analysis of the targeted lower extremity National Surgery Quality Improvement Program database from 2012 to 2017. We included patients who had been either asymptomatic or had presented with claudication. The primary outcome was a severe adverse outcome, including one or more of the following: death, myocardial infarction, amputation, bleeding, and cerebrovascular accident. We performed univariate logistic regression analysis to determine whether patients with longer operative times had had greater odds of experiencing a severe adverse outcome. We performed a multivariate analysis using a logistic regression model to identify variables predictive of the outcome of interest. RESULTS: A total of 4081 patients were included, 3478 with claudication and 603 without symptoms. Patients with unknown disease or critical limb ischemia were excluded. Of the 4081 patients, 3646 had undergone interventions in the femoropopliteal region (89.3%) and 406 in the tibial region (10.0%). For the remaining 29 patients, the location of the endovascular intervention was missing. The median operative time for all procedures was 84 minutes. On univariate analysis, an operative time >121 minutes was a significant predictor of a severe adverse outcome (P < .0001). We used a forward selection method to identify confounders and subsequently performed multivariate logistic regression. Even after controlling for confounders, an operative time >121 minutes remained a significant predictor of severe adverse outcomes. CONCLUSIONS: For patients with claudication and asymptomatic patients, prolonged operative times for elective endovascular procedures were associated with poor outcomes. After controlling for confounders, we found a statistically significant association between the procedure length and the occurrence of adverse outcomes. Specifically, an operating time >2 hours had had significantly greater odds of dying or experiencing myocardial infarction, amputation, or bleeding. Thus, surgeons should weigh the benefits and choice of endovascular intervention types against the risks of prolonged procedures.

Repeated Endovascular Interventions Are Worthwhile, Even After Thrombosis, to Maintain Long-Term Use of Autogenous Dialysis Fistulas.

OBJECTIVES: Patients often require multiple access re-interventions to improve fistula patency and the overall usable lifespan of autogenous arteriovenous fistula (aAVF). There is no consensus on the appropriate number of re-interventions after which an access should be abandoned and new access placed. We evaluated whether repeated endovascular interventions for failing/failed aAVF are worthwhile or futile. METHODS: A retrospective review was performed on aAVFs created between 2009-2014. Fistula function was evaluated until January 2017. Functional fistula patency (FFP) was defined as the total time of functional fistula use for hemodialysis, from time of cannulation to time of measurement or fistula abandonment, including all interventions performed to maintain/reestablish patency. Primary outcomes were FFP duration and number of post-dialysis interventions. RESULTS: The study included 163 patients. Mean age was 67 (SD = 15.03). The only variable statistically different between functional fistulas and abandoned fistulas was obesity (p = 0.03). At the end of the study period, 145 (89.0%) patients continued to have functional fistulas, and 73 (44.8%) patients died, but had functional fistulas at time of death. Median FFP for the functional group was 3.18 years (range 0.01-7.01 years) and median number of interventions was 1 (range 0-13). In 18 patients (11%), the fistula was abandoned, most commonly due to thrombosis (47.1%), followed by infection (23.5%). No fistula was abandoned because of an unacceptable rate of reintervention. Median FFP in the abandoned group was 0.91 years (range 0.03-5.30 years), and median number of interventions was 0 (range of 0-5). CONCLUSIONS: Through repeated interventions on aAVFs, none of the patients in our study exhausted all hemodialysis access options prior to transplantation, death or loss to follow-up. These results may indicate repeated and/or more frequent revisions do not negatively affect the FFP nor do they increase the overall risk for abandonment of aAVFs.

Increasing disparity between Society for Vascular Surgery guidelines for infrarenal abdominal aortic aneurysm repair and real-world practice.

OBJECTIVE: The current Society for Vascular Surgery (SVS) guidelines, based on randomized controlled trials published more than a decade ago, recommend a minimum threshold diameter of 5.5 cm for infrarenal abdominal aortic aneurysm (iAAA) repair. It is unknown whether practice patterns with respect to size of repair have changed since the publication of these guidelines. We aimed to evaluate the real-world practice of vascular surgeons in our region with respect to iAAA size at the time of repair, whether this has changed over the past 12 years and if any changes were associated with the repair type, open vs endovascular. METHODS: The Vascular Study Group of New England (VSGNE) database was used to identify all patients who received iAAA repair between 2003 and 2015. The primary end point was to quantify the annual percentage of iAAAs repaired in different size categories (≥5.5 cm; <5.5 cm but ≥5.0 cm; <5.0 cm) over the study time period and by type of repair. The secondary end points were morbidity and mortality in these groups. We excluded nonelective cases (ruptured or symptomatic), patients with coexisting iliac artery aneurysms, and those missing critical data. RESULTS: A total of 5314 patients with iAAA repairs (1538 open, 3776 endovascular) were identified in the VSGNE database during the study period. In 40% (2110 of 5314) of patients, repair was performed for aneurysms <5.5 cm, with endovascular aneurysm repair (EVAR) comprising 75% (1581 of 2110) and open 25% (529 of 2110). More EVARs were performed for <5.5 cm in 2015 (46%) compared with 2003 (33%) (P < .05, n - 1 χ2) with an average increase of 1.1%/y. There was also a non-statistically significant increase in open repair of small aneurysms (0.7%/y; P = .759). Overall, 30-day mortality was 1.11% in the EVAR group (0.54% in <5.0 cm, 0.91% in ≥5.0 but <5.5 cm, and 1.55% in ≥5.5 cm), compared with 3% in the open group (2.88%, 1.79%, and 3.77%, respectively) with no significant change in mortality in either group over time. CONCLUSIONS: Despite the SVS guidelines suggesting surveillance rather than repair of iAAA <5.5 cm, an increasing proportion of repairs in the VSGNE database were performed below that threshold. The reasons for this are likely multifactorial and might include a lesser complexity and lower operative mortality for smaller aneurysms and markedly improved third- and fourth-generation stent graft technology with possibly better long-term survival. As such, it may be time to re-examine the current guidelines for iAAA repair.

Active Tobacco Use in Patients with Claudication Does Not Affect Outcomes after Endovascular Interventions.

BACKGROUND: With the advent of endovascular procedures, the indications for intervention in claudicants have become less strict. Many interventionalists, however, will not intervene in patients with lifestyle-limiting claudication unless they have discontinued tobacco use. Many patients are unable to comply with this goal, and there is little published evidence to suggest that continued tobacco use results in poorer outcomes. We sought to determine if it is justified to deny this group of patients endovascular, potentially lifestyle-improving, procedures based on their outcomes. METHODS: A retrospective chart review was performed between 2007 and 2011 at a midsize community teaching hospital. Patients included had documented lifestyle-limiting claudication, underwent endovascular therapy, and had no previous vascular intervention. Patients were divided into 2 groups: active smokers (AS) and nonsmokers (NS) including former and never smokers. The primary outcome was the need for reintervention and the secondary outcomes were the need for surgical revascularization, limb loss, myocardial infarction (MI), stroke, and death. RESULTS: One hundred thirty-eight patients met inclusion criteria with 89 being male (64.5%). Forty-seven (34%) were active smokers versus 91 (66%) who were nonsmokers. Mean age at initial intervention for all 138 subjects was 66.34 years (standard deviation 10.7) and was not statistically different between the AS and NS groups. Mean follow-up was 3.6 years and was not significantly different between the two groups. Between the two groups (AS vs NS), there was no statistically significant difference between the rate of reintervention, surgical bypass, and limb loss. We also did not observe any significant difference in the rate of MI, stroke, or death during our follow-up period. CONCLUSIONS: Although tobacco use has been shown to negatively impact bypass patency, our data show that it does not appear to increase the need for reintervention, conversion to open surgical revascularization, limb loss, or other morbidities in patients undergoing endovascular interventions for claudication. We continue to strongly recommend all our patients who smoke to discontinue tobacco use. Our results, however, do not support the notion that those patients who are unable to quit should be denied the potential benefit of an endovascular intervention. The most important limitation of our study is the small numbers of patients available for review. Larger studies will be necessary to confirm our findings.

Rare Case of Acute Type B Dissection Causing Complete Collapse of EVAR Stent.

We describe a unique case of an acute type B aortic dissection in a patient with a history of a previously placed infrarenal aortic stent for an abdominal aortic aneurysm. The patient presented with a hypertensive emergency and left lower extremity ischemia, and imaging revealed complete collapse of the previously placed stent graft with extension into the iliac limbs. He underwent emergent endovascular intervention. When the false lumen was entered by puncturing the dissection plane with a sheath, immediate reexpansion of the stent graft was observed. The entry point of the dissection was covered with 2 overlapping stents, restoring flow within the true lumen. Although aortic stent collapse from acute type B aortic dissections is extremely rare, we demonstrate that endovascular release of the outflow obstruction and depressurizing the false lumen can resolve this dreaded complication.

Reporting standards of the Society for Vascular Surgery for endovascular treatment of chronic lower extremity peripheral artery disease: Executive summary.

Recommended reporting standards for lower extremity ischemia were last published by the Society for Vascular Surgery in 1997. Since that time, there has been a proliferation of endovascular therapies for the treatment of chronic peripheral arterial disease. The purpose of this document is to clarify and update these standards, specifically for reports on endovascular treatment. The document is divided into sections: Claudication Reporting, Critical Limb Ischemia Reporting, Preintervention Assessment and Nonanatomic Treatment, Intervention, Outcome Measures - Procedural, Outcome Measures - Disease Specific, and Complications.

Reporting standards of the Society for Vascular Surgery for endovascular treatment of chronic lower extremity peripheral artery disease.

Peripheral arterial disease (PAD) represents a spectrum from asymptomatic stenosis to limb-threatening ischemia. The last decade has seen a tremendous increase in the variety of endovascular devices and techniques to treat occlusive disease. Like many evolving technologies, the literature surrounding therapy for endovascular arterial disease consists of mixed-quality manuscripts without clear standardization. Accordingly, critical evaluation of the reported results may be problematic. As such, providers and their patients make treatment decisions without the full benefit of a comparative effectiveness framework. The purpose of this document is to provide a summary for the reporting of endovascular revascularization techniques in the setting of chronic disease. Much of the work in this document is based on prior publications and standards proposed by the Society for Vascular Surgery. We have also made recommendations based on current literature and have attempted to acknowledge shortcomings and areas for future research. The various sections contain summaries of required reporting standards and should serve as a guide for the design of clinical trials and as reference for journal editors and reviewers when considering scientific work pertaining to endovascular therapy for chronic lower extremity arterial disease. An Appendix is provided with commonly used abbreviations in this document.

Pharmacomechanical thrombectomy: 2015 update.

Pharmacomechanical Thrombectomy (PMT) is recognized as a recent advancement in the treatment of lower extremity deep venous thrombosis (DVT). Evidence for the use of this modality is growing rapidly, primarily based on anecdotal experience and large case series. Currently, the majority of patients with lower extremity DVT are treated with anticoagulation or compressive therapy without adjunctive surgical or interventional procedures. This article reviews the current evidence supporting the use of PMT over catheter directed thrombolysis or simple anticoagulation and the expected benefits that can be realized from each modality. In addition the relevant unique characteristics to each device currently available are described focusing on mechanism of action and potential side effects.

A model to demonstrate that endotension is a nonvisualized type I endoleak.

OBJECTIVE: Unexplained aneurysm growth despite multimodality imaging after endovascular aneurysm repair is often attributed to endotension. We tested a hypothesis that endotension may be from a type Ia endoleak pressurizing the aneurysm sac, without net forward flow, not visualized on standard angiographic imaging. METHODS: A patient-specific aortic aneurysm phantom was constructed of polyvinyl alcohol using three-dimensional molding techniques. A bifurcated stent graft was implanted, and the phantom was connected to a hemodynamic simulator for testing. Type Ia endoleaks were created using 7F catheters. Three scenarios were studied: complete exclusion (no endoleak), inflow with no sac outflow, and inflow with sac outflow. Imaging with digital subtraction angiography was performed at 48 kVp at 5 frames/s, followed by delayed imaging at 1 frame/min for 30 minutes. RESULTS: With no endoleak, the systemic pressure averaged 113 mm Hg and aneurysm sac pressure averaged 101 mm Hg. With an endoleak present without outflow, the systemic pressure averaged 116 mm Hg, the aneurysm sac pressure averaged 120 mm Hg, and endoleak flow was bidirectional with no net forward flow. With endoleak present with aneurysm sac outflow, the systemic pressure averaged 119 mm Hg, aneurysm sac pressure averaged 105.5 mm Hg, and net endoleak flow into the aneurysm sac was 21 mL/min across the endoleak channel. With digital subtraction imaging, the endoleak with no outflow was noted after >9 minutes of delayed imaging. CONCLUSIONS: In our model, the creation of a type Ia endoleak in the absence of sac outflow resulted in a mean pressure higher than the systemic mean pressure with zero net flow into the aneurysm sac. Consequently, the endoleak could only be visualized with markedly delayed imaging and not with standard contrast digital subtraction angiography like that used in clinical practice. Our findings suggest that endotension may in fact be the result of undetected endoleaks secondary to the limitations of present iodinated contrast imaging modalities.

Endovascular hypogastric artery preservation during endovascular aneurysm repair: a review of current techniques and devices.

Despite the improvement in endovascular techniques, one aspect of aneurysmal disease that continues to be challenging is the management of aortoiliac aneurysms. Sacrificing the hypogastric artery (HGA) for effective treatment is not without sequelae, which may include buttocks claudication, colonic ischemia, spinal cord ischemia, as well as buttock and scrotal necrosis. This should be taken into consideration particularly in patients with previous intervention or potential additional future interventions. This review describes the current endovascular techniques for preservation of HGA perfusion.

Iatrogenic May-Thurner syndrome after EVAR.

May-Thurner syndrome (MTS) is caused by compression of the left iliac vein between the right common iliac artery and the body of the fifth lumbar vertebra, resulting in hemodynamic compromise to venous return and intimal hyperplasia of the vein from chronic pulsatile compression. We report a case of MTS resulting from placement of an aortic stent graft for aneurysm repair. A higher index of suspicion and a more comprehensive initial venous duplex investigation, which should include the suprainguinal veins, should be considered in those patients with new onset of unilateral limb swelling after endovascular aneurysm repair (EVAR).

Acute upper extremity arterial thrombosis and stroke in an unresected pheochromocytoma.

Pheochromocytoma is a rare cause of hypertension in the general population. Only isolated reports show an association with acute obstructive arterial thrombosis. A 50-year-old chronically noncompliant woman with a known unresected pheochromocytoma presented to the emergency department with ataxia. Imaging confirmed a right-sided ischemic stroke. During her hospital stay, the patient developed signs consistent with acute right upper extremity ischemia resulting from occlusion in the distal right subclavian, axillary, and proximal brachial arteries. Emergent open thrombectomy was successfully performed. In patients with an unresected pheochromocytoma, one must consider acute arterial thrombosis as a rare but potentially limb-threatening and even life-threatening complication.

Clinical and anatomic outcomes of endovenous radiofrequency ablation performed on symptomatic small-diameter great saphenous veins.

OBJECTIVE: The efficacy of radiofrequency ablation (RFA) for symptomatic varicose veins is well established. Alternatively, there is less consensus and little data on outcomes when treating great saphenous veins (GSV) of small diameter (≤5 mm). The purpose of this study is to assess clinical and anatomical outcomes of RFA on symptomatic patients with small GSV. METHODS: A retrospective analysis was performed on our symptomatic patients who received RFA of incompetent GSV without any concomitant adjunctive procedures between January 2008 and December 2011. Limbs with GSV thigh diameter ≤5 mm and >5 mm on duplex while standing were subject to review. Clinical success was defined as an improvement in Venous Clinical Severity Score (VCSS) at 3 months. Anatomic success was defined as absence of venous flow ≤3 cm distal to the saphenofemoral junction on duplex ultrasound examination. Changes in CEAP class were noted. RESULTS: In 307 patients, 55 limbs in 44 patients met inclusion criteria. Baseline median VCSS was 4 (interquartile range [IQR], 4, 5) for those patients with diameter ≤5 mm. Clinical success was seen in 83% of limbs at 3 months with a median VCSS change of -2 (IQR, -3, -1). None of the treated limbs had phlebectomy for symptomatic refluxing GSV varicosities prior to 3-month follow up. One phlebectomy was performed for cosmesis at 78 days postprocedure. Anatomic success was achieved in 96% of limbs at 3 months. Baseline median CEAP was 2 (IQR, 2, 2). The median CEAP change at 3 months was 0 (IQR, -1, 0). One patient experienced thrombus extension into the saphenofemoral junction at 4 days. CONCLUSIONS: In our experience, RFA of symptomatic small-diameter GSV provides comparable clinical and anatomic outcomes to that of current published data. Our findings suggest that these patients benefit clinically from RFA.

Endovenous radiofrequency ablation for the treatment of varicose veins.

Chronic venous insufficiency (CVI) is the most common vascular disease and represents a significant health care problem in the United States. Reflux of the great saphenous vein is the most common cause of this condition, whose symptoms include varicose veins, leg swelling, skin discoloration, and ulceration. The traditional treatment of this condition is saphenofemoral ligation with stripping of the saphenous vein followed by varicose vein removal, if necessary. Recent advances in minimally invasive endovenous therapy have led to the development of catheter-based radiofrequency ablation (RFA) of the saphenous vein, which has gained an increasing acceptance in clinical practice. Endovenous RFA was introduced into clinical practice in Europe in 1998 and in the United States in 1999. Since then, over 250,000 procedures have been performed worldwide. Procedure safety and efficacy are well understood, with over 60 publications on the subject in the peer review literature, including four randomized trials comparing this technology with traditional vein stripping surgery. With the advent of tumescent anesthesia, the majority of RFA procedures are now performed in an office setting. This article examines the current technology using RFA in saphenous vein ablation with the Closure catheter system. Procedural techniques and clinical outcome using RFA in saphenous vein ablation are discussed. Clinical data comparing RFA versus saphenous vein stripping are also examined. Lastly, the clinical utility of a new RFA catheter, ClosureFAST, is discussed. ClosureFAST is a new generation of RFA catheter and has exhibited significant improvement in the ease of use and the procedure speed over the previous generation catheters while maintaining the favorable patient recovery profile seen with the RFA technology.

Radiofrequency ablation of the great saphenous vein performed in the office: tips for better patient convenience and comfort and how to perform it in less than an hour.

Radiofrequency ablation of the great saphenous vein has become increasingly popular for its decreased morbidity and greater patient satisfaction as compared with conventional saphenous vein stripping. Because of the relative simplicity and safety of this procedure and fueled by changes in reimbursement, endovenous radiofrequency ablation is now most often performed as an office-based procedure. This sets the stage for developing new technology that can achieve better results in a shorter time without compromise to patient safety and satisfaction. The balance between patient satisfaction and increased productivity is tenuous, and the former should never be sacrificed for the latter. The recipe for such a seemingly formidable task begins the moment the patient sets foot in the waiting area. Recognizing the steps that cause patient anxiety and strategically turning them into comfort zones takes a concerted effort between the surgeon and office staff. Here, we demonstrate how simple changes can transform an office-based endovenous practice into one in which patient and physician alike are maximally satisfied.