Miguel Montero-Baker

Retrograde Approach for Complex Popliteal and Tibioperoneal Occlusions

Purpose: To describe the technical aspects of the retrograde approach for endovascular treatment of complex popliteal and/or tibioperoneal occlusions and determine its efficacy in minimizing failure rates. Methods: An observational registry of retrograde revascularizations was maintained at our institution over 14 months (September 2006 to December 2007). During this time frame, antegrade revascularization failed in 62 (17.8%) of 343 limbs with complex total occlusions of the popliteal and/or infrapopliteal vascular territory. Of these antegrade failures, 51 (82.2%) limbs in 51 patients (32 men; mean age 72±8 years) were suitable for a retrograde attempt. From this subgroup, 45 (88.2%) were treated via a percutaneous transpedal access site and 6 (11.8%) via a transcollateral intra-arterial technique. Results: The overall success rate was 86.3% (44/51); adjunctive stenting was needed in 21 (41.1%) to optimize results. Only 1 (1.9%) major complication (a pedal access site occlusion) and 4 (7.8%) minor sequelae (arterial perforation in 3 and a pedal hematoma without consequence) were documented. Conclusion: In complex popliteal to infrapopliteal occlusions, an antegrade recanalization attempt can fail in up to 20% of the cases. The additional use of a retrograde approach seems feasible and safe and can favorably modify this failure rate. This technique could be valuable for patients with critical limb ischemia due to popliteal and infrapopliteal occlusions once larger studies with follow-up confirm safety, efficacy, and clinical benefit.

Systematic Review of Guidelines for the Management of Asymptomatic and Symptomatic Carotid Stenosis.

Background and Purpose— We systematically compared and appraised contemporary guidelines on management of asymptomatic and symptomatic carotid artery stenosis. Methods— We systematically searched for guideline recommendations on carotid endarterectomy (CEA) or carotid angioplasty/stenting (CAS) published in any language between January 1, 2008, and January 28, 2015. Only the latest guideline per writing group was selected. Each guideline was analyzed independently by 2 to 6 authors to determine clinical scenarios covered, recommendations given, and scientific evidence used. Results— Thirty-four eligible guidelines were identified from 23 different regions/countries in 6 languages. Of 28 guidelines with asymptomatic carotid artery stenosis procedural recommendations, 24 (86%) endorsed CEA (recommended it should or may be provided) for ≈50% to 99% average-surgical-risk asymptomatic carotid artery stenosis, 17 (61%) endorsed CAS, 8 (29%) opposed CAS, and 1 (4%) endorsed medical treatment alone. For asymptomatic carotid artery stenosis patients considered high-CEA-risk because of comorbidities, vascular anatomy, or undefined reasons, CAS was endorsed in 13 guidelines (46%). Thirty-one of 33 guidelines (94%) with symptomatic carotid artery stenosis procedural recommendations endorsed CEA for patients with ≈50% to 99% average-CEA-risk symptomatic carotid artery stenosis, 19 (58%) endorsed CAS and 9 (27%) opposed CAS. For high-CEA-risk symptomatic carotid artery stenosis because of comorbidities, vascular anatomy, or undefined reasons, CAS was endorsed in 27 guidelines (82%). Guideline procedural recommendations were based only on results of trials in which patients were randomized 12 to 34 years ago, rarely reflected medical treatment improvements and often understated potential CAS hazards. Qualifying terminology summarizing recommendations or evidence lacked standardization, impeding guideline interpretation, and comparison. Conclusions— This systematic review has identified many opportunities to modernize and otherwise improve carotid stenosis management guidelines.

Preliminary results of the initial United States experience with the Supera woven nitinol stent in the popliteal artery

BACKGROUND Popliteal artery stenting is not routinely performed due to concerns related to the high mobility of the knee joint and the potential for external stent compression, fractures, and occlusion. Open bypass is traditionally considered the gold standard for popliteal artery atherosclerotic lesions. The Supera stent (IDEV Technologies Inc, Webster, Tex) was developed to provide superior radial strength, fracture resistance, and flexibility compared with laser-cut nitinol stents. This study represents the initial United States experience in the management of popliteal artery atherosclerotic disease with the Supera interwoven wire stent. METHODS Patients undergoing stent implantation in the 20-month period after the 2008 Food and Drug Administration clearance were included. Medical records, radiographic imaging, and procedural data were examined. Procedural angiograms were classified according to Trans-Atlantic Inter-Society Consensus criteria. Patency and limb loss rates were calculated using Kaplan-Meier analysis. RESULTS A total of 39 stents were placed in 34 patients due to isolated popliteal artery occlusive disease. Clinical follow-up was a mean of 12.7 months (range, 0.2-33.7 months), and radiologic follow-up was a mean of 8.4 months (range, 0-26.8 months). Most patients had critical limb ischemia (CLI), with tissue loss (38.2%) or rest pain (35.3%) as the indication for intervention. In 20 patients (58.8%), the most distal end of the stent(s) landed in the below-the-knee popliteal segment, 12 (35.3%) landed in the above-the-knee segment, and two (5.9%) landed precisely at the knee. Other than angioplasty and stenting, 47% of patients did not receive any adjuvant concomitant therapy in the treated leg. Two patients underwent concomitant atherectomy of the popliteal segment. Primary, primary assisted, and secondary patency rates by duplex ultrasound imaging were 79.2%, 88.1% and 93%, respectively, by Kaplan-Meier estimates, with a mean stented length of 12 cm. Six instances of stent occlusion were noted, and six patients were identified with hemodynamically significant in-stent stenosis. Three patients sustained limb loss (8.8%), two related to uncontrolled infections, and one due to perioperative ischemic complications (both with patent stents at the time of limb loss). The overall mortality was 8.8% during the study period. Knee roentgenography was performed in all but one patient, and no stent fractures were identified. CONCLUSIONS Stenting of the popliteal artery using the Supera stent system appears to be safe and effective. The interwoven stent design may better serve areas under extreme mechanical stress. Our results with this highly diseased patient population justify a prospective trial in this subject.

Tibiopedal Access for Crossing of Infrainguinal Artery Occlusions: A Prospective Multicenter Observational Study

Purpose: To report a prospective, multicenter, observational study (ClinicalTrials.gov identifier NCT01609621) of the safety and effectiveness of tibiopedal access and retrograde crossing in the treatment of infrainguinal chronic total occlusions (CTOs). Methods: Twelve sites around the world prospectively enrolled 197 patients (mean age 71±11 years, range 41-93; 129 men) from May 2012 to July 2013 who met the inclusion criterion of at least one CTO for which a retrograde crossing procedure was planned or became necessary. The population consisted of 64 (32.5%) claudicants (Rutherford categories 2/3) and 133 (67.5%) patients with critical limb ischemia (Rutherford category ≥4). A primary antegrade attempt to cross had been made prior to the tibiopedal attempt in 132 (67.0%) cases. Techniques used for access, retrograde lesion crossing, and treatment were at the operator’s discretion. Follow-up data were obtained 30 days after the procedure. Results: Technical tibiopedal access success was achieved in 184 (93.4%) of 197 patients and technical occlusion crossing success in 157 (85.3%) of the 184 successful tibial accesses. Failed access attempts were more common in women (9 of 13 failures). The rate of successful crossing was roughly equivalent between sexes [84.7% (50/59) women compared to 85.6% (107/125) men]. Technical success did not differ significantly based on a prior failed antegrade attempt: the access success rate was 92.4% (122/132) after a failed antegrade access vs 95.4% (62/65) in those with a primary tibiopedal attempt (p=0.55). Similarly, crossing success was achieved in 82.8% (101/122) after a failed antegrade access vs 90.3% (56/62) for patients with no prior antegrade attempt (p=0.19). Minor complications related to the access site occurred in 11 (5.6%) cases; no patient had access vessel thrombosis, compartment syndrome, or surgical revascularization. Conclusion: Tibiopedal access appears to be safe and can be used effectively for the crossing of infrainguinal lesions in patients with severe lower limb ischemia.

The First-in-Man “Si Se Puede” Study for the use of micro-oxygen sensors (MOXYs) to determine dynamic relative oxygen indices in the feet of patients with limb-threatening ischemia during endovascular therapy

OBJECTIVE Patients with limb-threatening ischemia exhibit uneven patterns of perfusion in the foot, which makes it challenging to determine adequate topographic perfusion by angiography alone. This study assessed the feasibility of reporting dynamic relative oxygen indices and tissue oxygen concentration from multiple locations on the foot during endovascular therapy using a novel micro-oxygen sensor (MOXY; PROFUSA, Inc, South San Francisco, Calif) approach. METHODS A prospective, 28-day, single-arm, observational study was performed in 10 patients who underwent endovascular therapy for limb-threatening ischemia. At least 24 hours before therapy, four microsensors were injected in each patient (one in the arm, three in the treated foot). The optical signal from the microsensors corresponded to tissue oxygen concentration. A custom detector on the surface of the skin was used to continuously and noninvasively measure the signals from the microsensors. The ability to locate and read the signal from each injected microsensor was characterized. Oxygen data from the microsensors were collected throughout the revascularization procedure. The timing of therapy deployment was recorded during the procedure to assess its relationship with the microsensor oxygen data. Oxygen data collection and clinical evaluation were performed immediately postoperatively as well as postoperatively on days 7, 14, 21, and 28. RESULTS The study enrolled 10 patients (50% male) with ischemia (30% Rutherford class 4, 70% Rutherford class 5). Patients were a mean age of 70.7 years (range, 46-90 years), and all were Hispanic of varying origin. Microsensors were successfully read 206 of 212 times (97.2%) in all patients during the course of the study. Microsensors were compatible with intraoperative use in the interventional suite and postoperatively in an office setting. In nine of 10 revascularization procedures, at least one of the three MOXYs showed an immediate change in the dynamic relative oxygen index, correlating to deployed therapy. Moreover, there was a statistically significant increase in the concentration of oxygen in the foot in preoperative levels compared with postoperative levels. No adverse events occurred related to the microsensor materials. CONCLUSIONS This MOXY approach appears to be safe when implanted in patients with limb-threatening ischemia undergoing endovascular recanalization and is effective in reporting local tissue oxygen concentrations over a course of 28 days. Further testing is needed to determine its potential effect on clinical decision making, both acutely on-table and chronically as a surveillance modality, which ultimately can lead to improved healing and limb salvage.

Pharmacomechanical Thrombolysis in the Management of Acute Inferior Vena Cava Filter Occlusion Using the Trellis-8 Device

Purpose: To evaluate the performance and safety of the Trellis-8 system, a pharmacomechanical thrombolysis infusion catheter, and adjunctive therapies in the treatment of symptomatic inferior vena cava (IVC) filter–related acute thrombotic occlusion. Methods: Eight consecutive patients (6 men; mean age 57.4 years, range 34–78 years) with acute thrombotic occlusion of the IVC in the presence of an IVC filter underwent percutaneous venous thrombectomy using the Trellis-8 thrombectomy system and adjunctive techniques between January 2009 and November 2013. Demographics, clinical data, procedures, and outcomes were retrospectively reviewed. All patients had clinical signs of lower extremity venous hypertension on presentation. The median time between IVC filter placement and occlusion was 25 months. Patients were followed for the development of thromboembolic complications to the last clinic visit or until they died. Results: The procedure was technically successful in 6 patients, whereas it could not be performed in 2 due to failure to cross the occlusion. The median follow-up period was 7.8 months, at which time all patients undergoing successful Trellis-8 thrombectomy had relief of symptoms without thromboembolic or bleeding complications. Conclusion: In this limited performance and safety evaluation, the Trellis-8 thrombectomy system combined with adjunctive therapies, such as mechanical thrombectomy and balloon angioplasty, was effective in 75% of patients with IVC filter–related acute caval occlusion.

Die endovaskuläre Behandlung von Bauchaortenaneurysmen bei älteren Patienten (≥ 80 Jahre)

BACKGROUND The increase in life expectancy results in a higher number of patients with an advanced age over 80 years requiring abdominal aortic aneurysm therapy. The aim of this study was to review the outcome of octogenarians undergoing endovascular treatment for abdominal aortic aneurysms. PATIENTS AND METHODS Between June 2004 and March 2008 25 patients (24 males, one female), with a mean age of 83 +/- 2.6 years (range: 80-91 years) underwent elective endovascular treatment for abdominal aortic aneurysms. The average preoperative aneurysm diameter was 57 +/- 9.8 mm (range: 40-80 mm). All procedures were carried out in the angiography suite under general anesthesia. RESULTS Endovascular abdominal aortic aneurysm repair was technically successful in all patients. There was one perioperative death due to an aneurysm-related complication. The perioperative (30 days) mortality rate was 4 %. Intensive care unit admission was required in five patients. The in-hospital morbidity rate was 20 %. Mean follow-up time was 18.7 +/- 14 months (range: 2 to 47 months). Two patients died from unrelated causes. There were no device- or aneurysm-related deaths. A patient with a type I A endoleak underwent correction by additional stent-graft placement four weeks after initial placement. CONCLUSION Endovascular abdominal aortic aneurysm repair in octogenarians is a valuable alternative to open aortic repair and can be performed safely and successfully. We strongly recommend the endovascular treatment for patients over 80 years of age with an appropriate size of aortic aneurysm.

SS15. Using the Society for Vascular Surgery Wound, Ischemia, and Foot Infection (WIfI) Classification as a Tool to Identify Patients Most Likely to Benefit from Revascularization

P < .001) and low-PCT (hazard ratio, 0.6; 95% CI, 0.5-0.9; P 1⁄4 .007) were independently associated with loss of primary patency (Table). Conclusions: High PCT is associated with decreased patency and increased major adverse limb event as compared with low PCT after open and endovascular interventions for chronic limb ischemia. Patients with high PCT values might benefit from intensified antiplatelet therapy after interventions.

Technological Advances in Endovascular Surgery

The twentieth century witnessed a tremendous explosion in the application of minimally invasive, catheter-based interventions in virtually all vascular bed territories, surpassing the number of performed open surgical cases by the end of that time period. This fact allowed a greater number of patients to be candidates for potentially life-saving surgical interventions, many of whom could not have tolerated the superior stresses of an open surgical procedure. The development of such technological advances that can provide significant benefits to our patients does require the participation of both industry and physicians; neither group by themselves could achieve these goals in isolation. Such cooperation is a new paradigm, first tested during the development of laparoscopy in the general surgery specialty and clearly expanded in vascular surgery. Whereas no major technological advances have been reported during the beginning of the twenty-first century in open vascular surgery techniques, major improvements in the endovascular arena have been described, from the technological and technical points of view. This chapter is a concise review of the most recent and important techniques and device developments involved in vascular interventions.