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Objective: The optimal management of patients with asymptomatic carotid stenosis (AsxCS) is enduringly controversial. We updated our 2021 Expert Review and Position Statement, focusing on recent advances in the diagnosis and management of patients with AsxCS., Methods: A systematic review of the literature was performed up to August 1, 2023, using PubMed/PubMed Central, EMBASE and Scopus. The following keywords were used in various combinations: "asymptomatic carotid stenosis," "carotid endarterectomy" (CEA), "carotid artery stenting" (CAS), and "transcarotid artery revascularization" (TCAR). Areas covered included (i) improvements in best medical treatment (BMT) for patients with AsxCS and declining stroke risk, (ii) technological advances in surgical/endovascular skills/techniques and outcomes, (iii) risk factors, clinical/imaging characteristics and risk prediction models for the identification of high-risk AsxCS patient subgroups, and (iv) the association between cognitive dysfunction and AsxCS., Results: BMT is essential for all patients with AsxCS, regardless of whether they will eventually be offered CEA, CAS, or TCAR. Specific patient subgroups at high risk for stroke despite BMT should be considered for a carotid revascularization procedure. These patients include those with severe (≥80%) AsxCS, transcranial Doppler-detected microemboli, plaque echolucency on Duplex ultrasound examination, silent infarcts on brain computed tomography or magnetic resonance angiography scans, decreased cerebrovascular reserve, increased size of juxtaluminal hypoechoic area, AsxCS progression, carotid plaque ulceration, and intraplaque hemorrhage. Treatment of patients with AsxCS should be individualized, taking into consideration individual patient preferences and needs, clinical and imaging characteristics, and cultural, ethnic, and social factors. Solid evidence supporting or refuting an association between AsxCS and cognitive dysfunction is lacking., Conclusions: The optimal management of patients with AsxCS should include BMT for all individuals and a prophylactic carotid revascularization procedure (CEA, CAS, or TCAR) for some asymptomatic patient subgroups, additionally taking into consideration individual patient needs and preference, clinical and imaging characteristics, social and cultural factors, and the available stroke risk prediction models. Future studies should investigate the association between AsxCS with cognitive function and the role of carotid revascularization procedures in the progression or reversal of cognitive dysfunction., Competing Interests: Disclosures J.F.M. is co-Principal Investigator for the Clinical Coordinating Center of the CREST-2 multicenter randomized clinical trial (U01NS080168) and Principal Investigator of the Long-term Observational Extension of participants in the CREST-2 randomized clinical trial (C2LOE; U01NS119169). M.L.S. is the Principal Investigator of the ROADSTER-3 trial and is the Chair of the TCAR Surveillance Program in the Vascular Quality Initiative. L.H.B., P.J.N., and M.M.B. are co-Principal Investigators for the 2nd European Carotid Surgery Trial (ECST-2). P.S. is a consultant for Silk Road, Philips, Surmodics, Medtronic, Boston Scientific, Cagent, and LimFlow. E.A.S. has received research grants from the Food & Drug Administration (FDA), SCAI, BD, Boston Scientific, Cook, Laminate Medical, Medtronic, Philips, and NIH/NHLBIK23HL150290. He has received Consulting/Speaker fees from Abbott, Bayer, BD, Boston Scientific, Cook, Cordis, Heartflow, Inari, InfraRedx, Medtronic, Philips, RapidAI, Shockwave, and VentureMed. D.P.M. has given talks, acted as a consultant or attended conferences sponsored by Amgen and Novo Nordisk. B.K.L. is co-Principal Investigator of the CREST-2 multicenter randomized clinical trial (U01NS080168), Principal Investigator of the CREST-2 Registry (C2R; NCT02240862) and Principal Investigator for the Asymptomatic Carotid Stenosis and Cognitive Function Study (ACCOF; CX001621). The other authors have no conflicts of interest., (Copyright © 2023 Society for Vascular Surgery. All rights reserved.)

Objective: Over the years where stents have been used to treat carotid lesions, a great deal has been learned about which anatomic characteristics lead to adverse outcomes. This review summarizes the anatomic and morphologic characteristics of the carotid vasculature that can help guide patient selection and clinical decision-making., Methods: Each of the carotid artery anatomy and lesion characteristics that are relevant to carotid stenting is described in detail. These are accompanied with evidence-based outcomes and results., Results: Data on the prevalence of carotid artery lesions that are unsuitable for stenting are summarized and the implications of these data for practice are discussed, especially as they pertain to transcarotid artery revascularization., Conclusions: Carotid artery stenting can be a viable option for carotid revascularization, but the lesion must be acceptable and safe for stent placement. There should be thorough assessment to rule out the presence of severe tortuosity, long-segment disease, severe calcification (circumferential or exophytic), mobile plaque, swollen internal carotid artery sign, and carotid diameters outside the acceptable range. In carefully chosen lesions with the absence of the unfavorable characteristics described, transcarotid artery revascularization may offer improved periprocedural success and carotid artery stenting may attain better long-term durability., (Copyright © 2021 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: We report the 6- and 12-month outcomes of the PROMISE I early feasibility study after treatment of no-option chronic limb-threatening ischemia (CLTI) with percutaneous deep vein arterialization (pDVA) using the LimFlow System., Methods: Thirty-two patients with no-option CLTI, previously offered major amputation, were enrolled in this single-arm early feasibility study of the LimFlow pDVA System. No-option CLTI was defined as being ineligible for surgical or endovascular arterial revascularization. Patients were assessed for clinical status, pain, wound healing, and duplex ultrasound at 30 days, 6 months, and 12 months post-treatment. Primary endpoint analysis was amputation-free survival (AFS) at 30 days and 6 and 12 months. AFS was defined as freedom from above-ankle amputation of the index limb and freedom from all-cause mortality. Secondary endpoints evaluated included technical success of the procedure, and wound healing at 6 and 12 months., Results: Of 32 enrolled patients, 31 (97%) were successfully treated with the LimFlow System at the time of the procedure, and two (6.3%) were lost to follow-up. The 30-day, 6-month, and 12-month AFS rates were 91%, 74%, and 70% respectively. The wound healing status of fully healed or healing was 67% at 6 months, and 75% at 12 months. Reintervention was performed in 16 patients (52%) with 14 (88%) of the maintenance reinterventions occurring within the first 3 months. The majority of reinterventions (n = 12; 75%), involved the arterial inflow tract proximal to the stented LimFlow circuit, and no in-stent stenoses were determined to have been the cause of reintervention., Conclusions: The LimFlow pDVA System was utilized in treating patients with no-option CLTI. A high technical success rate was observed, with a significant percentage of patients surviving free of major amputation at 12 months. These results suggest early safety and provide an initial assessment of the efficacy of the LimFlow pDVA System that supports the expansion of carefully executed studies to determine whether this is a viable option that can be used in this critically disadvantaged and growing patient population., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: The DETOUR 1 study was performed to assess the safety of the femoral vein as a "pass through" conduit for covered stent placement during fully percutaneous femoropopliteal bypass, also known as the DETOUR procedure., Methods: At eight participating centers in this prospective, single-arm, international trial, 78 patients (82 femoropopliteal lesions) were enrolled. All patients had patent femoral veins measuring ≥10 mm in diameter at baseline. The DETOUR procedure involved delivery of a series of TORUS stent grafts, deployed from contralateral common femoral artery access, to the ipsilateral proximal superficial femoral artery, with entry into the femoral vein and re-entry into the arterial vasculature at the above-the-knee popliteal artery. The TORUS stent grafts are deployed in an overlapping configuration as an arterial-arterial conduit. Due to this novel transvenous approach, we assessed specific considerations related to the venous system to analyze the risk of risk of venous thromboembolic complications. Symptomatic deep vein thrombosis, nonocclusive material associated with the graft such as benign endovenous graft-associated material, pulmonary embolism, Venous Clinical Severity Score (VCSS) and Villalta scores, and luminal occupancy by the stent graft were assessed as the ratio of cross-sectional areas of the stent graft to the native vein at baseline and 1 year after the procedure., Results: A duplicate femoral vein was present in 20.7% of cases. The majority of patients (86.8%) had a femoral vein luminal area preservation of ≥55%. Thirty-two patients experienced an increase in the vein diameter over time after the procedure, but this pattern of venous remodeling was not uniform. The patients who had a compensatory increase in the vein diameter had a smaller average baseline vein diameter compared with the patients who did not have a compensatory increase in vein diameter (P = .0414). Only two patients (2.4%) developed ipsilateral symptomatic deep vein thrombosis) through 1 year of follow-up. There were no pulmonary embolism in any patient in the series. The overall VCSS and Villata scores did not change during follow-up. Mean VCSS and Villata were 0.8 ± 1.4 and 0.5 ± 1.1 at 1 year, compared with 0.6 ± 1.0 and 0.4 ± 0.9 at baseline, respectively., Conclusions: As a percutaneous alternative to open surgical bypass for complex femoropopliteal peripheral arterial disease, the transvenous bypass has a low rate of deep venous thrombotic and obstructive complications. Cross-sectional vein area is preserved, and in some patients, the compensatory vein diameter increases with time, supporting the feasibility and safety of using the lower extremity deep venous system as a pass-through conduit for the DETOUR percutaneous femoropopliteal bypass., Trial Registration: NCT02471638., (Copyright © 2021 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: The SCAFFOLD trial evaluated the GORE® Carotid Stent (GCS), a novel, mesh-covered device and evaluated outcomes at 1 year., Background: SCAFFOLD was a prospective, multicenter, single-arm clinical trial in patients with severe carotid artery stenosis (angiographically defined as symptomatic ≥50% or asymptomatic ≥80%) at increased risk for adverse events from carotid endarterectomy. Interim 30-day analysis demonstrated low rates of death/stroke/myocardial infarction (DSMI; 3.0%) and stroke (1.1%) in a high surgical risk population., Methods: The rate of DSMI within 30 days plus ipsilateral stroke between 31 days and 1 year (primary endpoint) was compared to a predetermined performance goal. Secondary outcomes of freedom from clinically driven target lesion revascularization (CD-TLR; diameter stenosis ≥80% by core lab angiography, or ≥50% with clinical symptoms) and restenosis (≥80% diameter stenosis by core lab angiography) are reported as Kaplan-Meier (KM) estimates., Results: Of the 312 patients enrolled and treated, 264 were eligible per protocol and evaluable for major adverse events at 30 days, and 244 (92%) of these were evaluable at 1 year. The proportion of patients with DSMI at 1 year was 4.5% and was significantly lower than the prespecified performance goal of 16.9% (p < .00001). The proportion with ipsilateral stroke from 31 to 365 days was 1.2%. The KM estimates of 1-year event probability were 1.6% for CD-TLR and 1.2% for restenosis., Conclusions: Use of the mesh-covered GCS in the SCAFFOLD trial demonstrated 100% technical success and low rates of both periprocedural and late stroke, with durable patency at 1 year. ClinicalTrials.gov Identifier: NCT01901874 (redacted)., (© 2019 Wiley Periodicals, Inc.)

Carotid stent angioplasty (CAS) has been shown to protect patient from future stroke long-term efficacy similar to carotid endarterectomy (CEA). The risk of minor stroke in the perioperative period is higher than with CEA and not related to cerebral protection during the CAS procedure since a significant portion of the neurologic events occur between 1 and 30 days following stent deployment. This observation suggests mechanisms integral to the stent itself may be pertinent such as plaque embolization thru the stent struts may occur. It appears that this embolic risk can be reduced by use of specific carotid stent designs that include a mesh covering to minimize the open struts areas and thus embolization through the carotid stent. Improvements in stent design that eliminate post-procedural debris embolization will expand the application of CAS for severe internal carotid artery atherosclerotic stenosis., (Copyright © 2017. Published by Elsevier Inc.)

A significant subset of patients with peripheral artery disease (PAD) has iliac artery involvement that requires treatment. The development of bare metal stents has improved the short- and long-term outcomes of endovascular repair and has become first line therapy. Open surgical bypass has been reserved for extremely complex anatomic morphologies or endovascular failures. It is unclear whether primary stenting is superior to angioplasty with provisional stenting but if angioplasty is used alone, it is likely only appropriate for the most focal lesions. Self-expanding and balloon-expandable stents have unique characteristics that are suitable to different lesion morphologies. Both stent-types have demonstrated similar outcomes. Herein, we review the practice and results of bare metal stents in the iliac arteries.

Background: Effectiveness of carotid artery stenting (CAS) relative to carotid endarterectomy (CEA) among Medicare patients has not been established. We compared effectiveness of CAS versus CEA among Medicare beneficiaries., Methods and Results: We linked Medicare data (2000-2009) to the Society for Vascular Surgery's Vascular Registry (2005-2008) and the National Cardiovascular Data Registry's (NCDR) Carotid Artery Revascularization and Endarterectomy Registry (2006-2008/2009). Medicare patients were followed up from procedure date until death, stroke/transient ischemic attack, periprocedural myocardial infarction, or a composite end point for these outcomes. We derived high-dimensional propensity scores using registry and Medicare data to control for patient factors and adjusted for provider factors in a Cox regression model comparing CAS with CEA. Among 5254 Society for Vascular Surgery's Vascular Registry (1999 CAS; 3255 CEA) and 4055 Carotid Artery Revascularization and Endarterectomy Registry (2824 CAS; 1231 CEA) Medicare patients, CAS patients had a higher comorbidity burden and were more likely to be at high surgical risk (Society for Vascular Surgery's Vascular Registry: 96.7% versus 44.5%; Carotid Artery Revascularization and Endarterectomy Registry: 71.3% versus 44.7%). Unadjusted outcome risks were higher for CAS. Mortality risks remained elevated for CAS after adjusting for patient-level factors (hazard ratio, 1.24; 95% confidence interval, 1.06-1.46). After further adjustment for provider factors, differences between CAS and CEA were attenuated or no longer present (hazard ratio for mortality, 1.13; 95% confidence interval, 0.94-1.37). Performance was comparable across subgroups defined by sex and degree of carotid stenosis, but there was a nonsignificant trend suggesting a higher risk of adverse outcomes in older (>80) and symptomatic patients undergoing CAS., Conclusions: Outcomes after CAS and CEA among Medicare beneficiaries were comparable after adjusting for both patient- and provider-level factors., (© 2016 American Heart Association, Inc.)

Objectives: This study provides preliminary data on the safety and feasibility of the use of a novel focal implant for managing post-percutaneous transluminal balloon angioplasty (post-PTA) dissection., Background: Post-PTA dissection of the lower extremity arteries is managed with stent placement. This provides an acceptable post-intervention result but has long-term disadvantages, such as in-stent restenosis. Focal treatment of post-PTA dissection and avoidance of stents are the objectives of the Tack-It (Intact Vascular, Inc., Wayne, Pennsylvania) device., Methods: A preclinical study and first-in-human data are presented. Seven swine underwent superficial femoral artery device placement, with a self-expanding nitinol stent on 1 side and a series of 4 Tack-It devices on the other side. Specimens were harvested at 28 days. The clinical study included 15 limbs that underwent revascularization for critical limb ischemia (n = 9) or claudication (n = 6). Twenty-five lesions were treated in the superficial femoral (n = 8), popliteal (n = 7), and tibial (n = 10) arteries., Results: The preclinical study demonstrated a reduction in stenosis with the Tack-It (16.8 ± 2.6%) compared with stents (46.4 ± 9.8%). Neointimal thickness and injury score decreased with the Tack-It. Clinically, Tack-It placement resulted in acute technical success with resolution of the post-PTA dissection in 100% of lesions. There were no device-related complications or major amputations. Eighteen of the 25 lesions were available for angiographic follow-up at 1-year, and patency was 83.3%., Conclusions: Preclinical data suggest that the Tack-It device causes minimal vessel injury. Clinical use of the Tack-It to manage post-PTA dissection was safe and feasible in this early study and resulted in apposition of dissection flaps without stent placement., (Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

The establishment of cerebral protection has matured conceptually and clinically in recent years. We have accepted that some type of cerebral protection is desirable. We have some choices in whether to use filters, proximal occlusion, or proximal occlusion with reversed flow. There are anatomical and clinical factors that drive the choice of cerebral protection devices. Certain practical applications of cerebral protection technologies can be made based upon clinical experience. Making carotid artery stenting (CAS) safer is the key to a broader application of CAS as a treatment method and optimal selection of atherosclerosis new cerebral protection devices helps to achieve that goal.

Vascular surgery has matured to the point that there exists robust bodies of literature exploring many of our therapies. However, this evidence is but one of the factors that dictate medical practice. Others include local patient demographics, the practical implications of healthcare delivery, and an individual surgeon's interpretation of this evidence, which can be somewhat subjective. As a result, there are numerous examples of vascular specialists' practice patterns differing depending on their geographic location. Recognizing this, the Editors of the Journal of Vascular Surgery and the European Journal of Vascular and Endovascular Surgery have developed a series of Trans-Atlantic Debates to explore these instances. The inaugural debate explores the controversial question of how best to manage asymptomatic carotid artery stenoses. Our debators, Peter Schneider and Ross Naylor, offer reasoned and passionate arguments to defend their differing approaches. We trust that this addition to our journals will prove enlightening and, perhaps, entertaining., (Copyright (c) 2010 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Whether performing carotid endarterectomy or carotid stenting, patients are selected on the basis of their anatomical suitability for these procedures. The procedure is then tailored to the specific anatomy with which the patient presented. As a result, outcomes of both carotid endarterectomy and stenting are significantly influenced by anatomical considerations and good outcomes are determined, at least in part, by selecting, understanding, and managing a wide variety of anatomical presentations.

Carotid stenting will drastically alter the management of carotid bifurcation stenosis. Key factors to include when initiating a carotid stent program are discussed. Questions addressed include the following: Who has clinical responsibility for patients with carotid disease? What is the rationale for a carotid stent program? How does one initiate a carotid stent program? How does one deal with endovascular realities? Training, patient selection, quality improvement, and proctoring are also reviewed.

Future participation in the treatment of carotid occlusive disease is dependent on training to perform carotid stent placement. Reviewed herein are strategies for training in carotid stenting. Included in this discussion are; the skills required for carotid stenting, the carotid stent learning curve, a comparison of training and credentialing, and the roles of simulators, courses, and hands-on experience in carotid stent training.

Although it has been clearly established that in certain groups of patients, such as in patients with symptomatic high-grade carotid stenosis and in selected asymptomatic patients with high-grade stenosis, carotid endarterectomy offers significant protection from stroke compared with medical therapy, the role of carotid stenting in this patients versus carotid endarterectomy is undergoing a rapid evolution. The definitive evidence awaits the results of ongoing prospective, randomized trials such as CREST and others, but it is clear that carotid stenting will increasingly occupy a significant role in the therapy of carotid bifurcation disease. In that context, vascular surgeons, traditionally the experts on the management of this condition, face the specter of other disciplines intervening in its treatment. In addition, if vascular surgeons do not acquire the skills and the expertise necessary to perform carotid stenting, it is self-evident that they run the risk of being spectators rather retaining the mantle of expert in the management of carotid bifurcation disease. As such, it is the duty of vascular surgeons to acquire the skills with which to retain their rightful place in its management and treatment. The purpose of this article is to describe the skills necessary to become competent in the endovascular management of carotid disease, offer some thoughts and strategy by which one can gain experience and develop an armamentarium of skills necessary to perform carotid stenting, and offer a comprehensive array of options of management and treatment to the patient with carotid disease.

From an initially simple concept, vascular stents have evolved into highly specialized instruments, and are poised to develop into sophisticated drug-delivery systems. Although primary research has mostly targeted the coronary circulation, newer generation stents, deliverable almost anywhere, retarding neointimal hyperplasia and thrombosis, and promoting endothelial overgrowth, will offer the next approximation of true vascular healing. This, in turn,promises to promote less invasive, safer, and finally durable endovascular solutions to current surgical problems.

Inflow iliac artery balloon angioplasty may be performed simultaneously with open infrainguinal vascular reconstruction in patients with multilevel occlusive disease of the lower extremity. This approach is safe, effective, has satisfactory long-term results, and should be part of the vascular armamentarium.

The risk of embolization during carotid artery stenting (CAS) has been the foremost reason for the cautious acceptance of this percutaneous alternative to carotid endarterectomy. To address this issue, numerous embolic protection devices are being evaluated as an adjunct to CAS for neuroprotection. Among the 3 main categories of these devices, distal filters, which trap embolic debris while maintaining distal cerebral perfusion, have attracted the most corporate interest. This review focuses on the emerging field of embolic protection filters for use in CAS.

Objective: This study was undertaken to determine the results and complications of stents placed for initially unsuccessful or complicated iliac percutaneous transluminal angioplasty (PTA), the effect of location (external iliac or common iliac) on outcome, and the influence of superficial femoral artery patency on benefit., Design: From 1992 through 1997, 350 patients underwent iliac artery PTA at the authors' institutions. Of this group, 88 patients (88 arteries) had one or more stents placed after PTA (140 stents in total) for residual stenosis or pressure gradient (63 patients), iliac dissection (12 patients), long-segment occlusion (10 patients), or recurrent stenosis (3 patients). Thirty patients required the placement of more than one stent. The indications for PTA in these 88 patients were claudication (48 patients) and limb-threatening ischemia (40 patients). Forty-seven patients had stents placed in the common iliac, 29 patients had stents placed in the external iliac, and 12 patients had stents placed in both. Seventy-one arteries (81%) were stenotic, and 17 (19%) were occluded before PTA. Sixty-six arteries were treated by interventional radiologists, 15 by a vascular surgeon, and 7 jointly., Main Outcome Measure: Criteria for success included (1) increase of at least one clinical category of chronic limb ischemia from baseline or satisfactory wound healing, (2) maintenance of an ankle/brachial index increase of more than 0.10 above the preprocedure index, and (3) residual angiographic stenosis less than 25% and, for patients with pressure gradient measurements, a residual gradient less than 10 mm Hg., Results: Stent placement was accomplished in all 88 patients with 16 (18%) major complications. Mean follow-up was 17 months (range, 3 to 48 months). By life-table analysis, success was 75% at 1 year, 62% at 2 years, and 57% at 3 years. No cardiovascular risk factor or independent variable was statistically significant in predicting success. There was no difference in success rates for common iliac or external iliac lesions. Superficial femoral artery patency did not correlate with outcome., Conclusions: Although stents can eliminate residual lesions and arterial dissection, these patients are likely to require adjuvant or subsequent procedures to attain clinical success. By controlling the PTA complication and treating the emergent problem, stents may allow for subsequent elective intervention.

Developing endoluminal technology has permitted the management of selected aneurysms using stent-grafts, but the applicability and durability of these new devices has not yet been proven. Standard treatment of mycotic aneurysms generally requires arterial ligation, excision and debridement, and autologous or extraanatomic synthetic bypass. A saphenous vein-covered stent was used to exclude an expanding, mycotic, superficial femoral artery aneurysm in a critically ill patient. Although stent-graft exclusion was intended as a bridge to standard therapy, the mass resolved, the superficial femoral artery remains patent, and the patient is symptom-free at 1 year without further intervention. Additional experience is required to determine whether stent-grafts have a role in the management of mycotic aneurysms.

Balloon angioplasty has been combined with open vascular surgery to treat lower extremity ischemia due to multilevel occlusive disease. The purposes of this study were: (1) to compare staged and simultaneous approaches to determine the optimal method for combining endovascular and open techniques and; (2) to assess the role of stents in intraoperative balloon angioplasty. Among 274 patients undergoing lower extremity revascularization over 30 months, 38 (13.9%) required a combination of endovascular and open techniques; 17 were staged (endovascular followed at an interval by distal open surgery) and 21 were simultaneous (intraoperative balloon angioplasty with or without stent placement at the time of open surgery). Groups were similar with respect to demographics, lesions treated with endovascular intervention, incidence and location of stent placement, and results of surgery. Additional operating time required for intraoperative endovascular intervention was 41.0 +/- 30.7 min., fluoroscopic time was 3.9 +/- 2.4 min. and contrast administered was 58.8 +/- 28.1 ml. There was no perioperative mortality. Length of stay was longer in the staged than in the simultaneous group (p < 0.01). Cumulative combined primary patency at 1 year by life-table methods was 82 +/- 10% in the staged group and 83 +/- 9% in the simultaneous group (p = 0.79). Mean follow-up was 13 +/- 6 months. There is a role for balloon angioplasty and stent placement in operative revascularization of ischemic limbs in selected patients: patency was similar to that produced with the staged approach while the length of stay was shorter. Intraoperative balloon angioplasty is safe and effective and stents permit a measure of control in assuring an optimal intraoperative postangioplasty result.