Immediate and late outcomes of subclavian artery stenting

Percutaneous Transluminal Angioplasty of Subclavian Artery Lesions

Introduction:

Percutaneous transluminal angioplasty (PTA) is one of the treatment options for stenotic and obstructive lesions of the subclavian artery.

Aim:

To evaluate initial and long-term results of percutaneous transluminal angioplasty of subclavian artery lesions.

Methods:

During period February 2016 to December 2017, 26 patients (12 men and 14 women) with significant subclavian artery stenosis and occlusion were admitted and underwent PTA. All patients were symptomatic. All PTA procedures were performed with the patient under local anesthesia, through the femoral artery (n=22), brachial artery (n=4), or combined route (n=6). In 7 patients, we performed direct stenting, while in the other 15 patients we performed predilatation before stent implantation. The follow-up protocol consisted of regular clinical examinations in 1, 3, 6 and 12 months post-procedural, and annually thereafter with duplex ultrasound monitoring.

Results:

Initial technical success was achieved in 22 of 26 procedures (84.61%), 100% in stenotic lesions and 55.5 % in total occlusions. Fourth of nine occlusions could not be recanalized by PTA. These patients were managed surgically. The 30-day mortality rate was 0% for the entire group. No patients required reintervention for recurrence of symptoms and the stents remain patent at period of 12 months post-procedural.

Conclusion:

The minimal invasive technique, the markedly lower complication rate, the high long-term patency, patient’s comfort and the decreased hospital stay have made endovascular repair the primary choice of treatment in the majority of cases, especially in patients with stenotic lesions and high-risk patients. We consider PTA of subclavian artery stenotic/obstructive lesions should be the first therapeutic option.

Transposition of Subclavian Artery - Is It the Appropriate Choice?

INTRODUCTION

To present patients with symptomatic subclavian artery disease and treatment possibility.

CASE REPORT

A 53-year-old female was admitted with vertigo and left arm claudication. Duplex-scan and MSCT arteriography verified subclavian artery occlusion. After the endovascular treatment failure, the patient was switched to surgical treatment - subclavian artery transposition. After the successful surgical treatment, the patient was discharged on the second postoperative day. If the patient is a candidate for surgery, the literature review shows good initial and long-term results after the subclavian artery transposition, and emphasizes this technique as superior.

CONCLUSION

Subclavian carotid transposition is a safe and effective method of treatment in patients after endovascular treatment failure or other indication. Also, the surgical treatment is technically demanding because of the difficult access to the vessel origin, and it requires experienced surgeons.

Coronary-Subclavian Steal: Case Series and Review of Diagnostic and Therapeutic Strategies

Due to the increased use of internal mammary artery grafts for coronary revascularization, proximal subclavian stenosis resulting in coronary-subclavian steal has become an important clinical entity. Patients present with varying signs and symptoms of recurrent myocardial ischemia that not only can limit lifestyle but also be life-threatening. A careful history and physical examination with the identification of risk factors such as peripheral vascular disease and arm blood pressure differential >20 mm Hg can identify patents at high risk for developing this syndrome. Identifying these patients before coronary artery bypass grafting can prevent this important problem by altering the therapeutic approach to coronary revascularization. When patients present after coronary artery bypass grafting with coronary-subclavian steal, therapeutic options of percutaneous transluminal angioplasty and stent placement to the subclavian artery, carotid-subclavian bypass, and axillary-axillary bypass all have high success rates with excellent long-term patency rates. The choice for the type of revascularization needs to be individualized based on the lesion morphology and clinical comorbidities. Three patients who presented with signs and symptoms of myocardial ischemia due to coronary subclavian steal are presented. All 3 patients had incapacitating symptoms, and all 3 were treated successfully with different revascularization techniques due to other medical conditions or comorbidities.

Distal Embolization During Percutaneous Subclavian Artery Intervention

Distal embolization due to atherothrombotic debris during subclavian artery interventions is extremely rare and can usually be managed conservatively. Herein, we describe a case of acute hand ischemia due to massive distal embolization during balloon angioplasty and stenting of a left subclavian artery chronic total occlusion. This limb-threatening complication was effectively treated with rescue surgical thrombectomy.

Adjuvant spinal cord stimulation improves wound healing of peripheral tissue loss due to steal syndrome of the hand: clinical challenge treating a difficult case

Hand ischaemia due to arterial steal syndrome is an infrequent, but potentially serious complication of arteriovenous fistula (AVF) for haemodialysis. We present a case of hand ischaemia caused by steal syndrome in a 69-year-old haemodialysis patient, 10 months after a brachiobasilic fistula creation. The patient underwent multiple operations without resolution of hand pain and tissue loss. The implantation of an adjuvant cervical spinal cord stimulator allowed the patient to obtain complete hand pain relief and wound healing. Probably, the diffuse microangiopathy typical of haemodialysis patients could be responsible for the persistence of ischaemic signs and symptoms after a surgical revascularisation. The effect of sympathetic blockade and the subsequent improvement of the arterial blood flow and tissue oxygenation because of spinal cord stimulation (SCS) can be useful to achieve complete ischaemic pain relief in order to enhance wound healing and to limit the tissue loss. In conclusion, the association of cervical spinal cord stimulation and surgical revascularisation could represent a valid option to treat a critical upper limb ischaemia following steal syndrome due to AVF.

Long-term results of primary stenting for subclavian artery disease

OBJECTIVES

To evaluate initial and long-term results of endovascular therapy (EVT) for symptomatic subclavian artery (SCA) disease.

BACKGROUND

EVT for SCA disease has a similar success rate as open surgery, but the long-term patency of EVT alone is uncertain.

METHODS

We retrospectively studied 59 consecutive patients (42 males and 17 females) with 60 lesions. Mean patient age was 68 ± 10 years. Clinical symptoms were vertebrobasilar insufficiency in 21 patients (35.0%), arm claudication in 20 patients (33.3%), angina pectoris in 12 patients (20%), severe arm ischemia in 3 patients (5.0%), vascular access insufficiency in 3 patients (5.0%), and leg ischemia in 1 patient (1.7%). A total of 57 stents were implanted. All patients were followed up at 1, 3, 6, and 12 months after the procedure and annually thereafter.

RESULTS

The technical success rate was 93.3%. All patients for whom technical success was obtained received stents. There were four technical failures, all of which were owing to the failure of crossing the wire in occluded lesions. There were no procedure-related deaths. There were two stroke events (3.4%) and one embolic event (1.7%). Primary patency rates were 94.9, 90.8, and 85.8% at 1, 3, and 5 years, respectively.

CONCLUSIONS

EVT for SCA disease is an effective treatment with regard to initial success rate, clinical efficacy, and long-term primary patency. This minimally invasive procedure is appropriate as the treatment of first choice for proximal subclavian arterial obstructive disease.

Endovascular Management of Aortic Arch Vessel Occlusion

A 56-year-old female presented with pain in her bilateral upper extremities. Angiogram demonstrated occlusion of her left subclavian and innominate arteries (IAs). The patient’s left subclavian occlusion was successfully treated with percutaneous mechanical thrombectomy, angioplasty, and stenting. One month later, endovascular revascularization of the IA was performed. Initially the lesion could not be directly transversed from neither an antegrade nor a retrograde approach. Wires were passed from the brachial and femoral arteries into the right common carotid artery where the femoral wire was snared and brought out through the right brachial access. Over this through-and-through wire access, angioplasty and stenting of the IA was performed with an excellent angiographic result. In follow-up, the patient remained free of upper extremity symptoms. Occlusive lesions of the aortic arch vessels can be successfully managed with antegrade and retrograde endovascular techniques.

Subclavian artery stenosis: a review for the vascular medicine practitioner

Peripheral artery disease assessment typically focuses on the evaluation of lower extremity symptoms and physical findings. Few practitioners consider the importance of upper extremity arterial disease; which, besides causing hand and arm symptoms, can be associated with significant neurologic and cardiac sequelae. A review of the existing literature through PubMed using the search term 'subclavian stenosis' was performed. The latest original articles, including clinical studies, case reports and limited reviews of this topic were adapted. A comprehensive article review focusing on the diagnostic and treatment approach for subclavian stenosis was prepared. In conclusion, vascular medicine practitioners including cardiologists and vascular surgeons caring for patients with arterial disease should routinely assess for subclavian stenosis. There are excellent screening tools and effective medical therapies which can be instituted if diagnosed early. When the need for revascularization arises, percutaneous modalities are favored given their proven long-term efficacy, decreased morbidity and mortality, and cost-effectiveness.

Endovascular treatment of peripheral vascular disease

Peripheral arterial disease (PAD) affects about 27 million people in North America and Europe, accounting for up to 413,000 hospitalizations per year with 88,000 hospitalizations involving the lower extremities and 28,000 involving embolectomy or thrombectomy of lower limb arteries. Many patients are asymptomatic and, among symptomatic patients, atypical symptoms are more common than classic claudication. Peripheral arterial disease also correlates strongly with risk of major cardiovascular events, and patients with PAD have a high prevalence of coexistent coronary and cerebrovascular disease. Because the prevalence of PAD increases progressively with age, PAD is a growing clinical problem due to the increasingly aged population in the United States and other developed countries. Until recently, vascular surgical procedures were the only alternative to medical therapy in such patients. Today, endovascular practice, percutaneous transluminal angioplasty with or without stenting, is used far more frequently for all types of lower extremity occlusive lesions, reflecting the continuing advances in imaging techniques, angioplasty equipment, and endovascular expertise. The role of endovascular intervention in the treatment of limb-threatening ischemia is also expanding, and its promise of limb salvage and symptom relief with reduced morbidity and mortality makes percutaneous transluminal angioplasty/stenting an attractive alternative to surgery and, as most endovascular interventions are performed on an outpatient basis, hospital costs are cut considerably. In this monograph we discuss current endovascular intervention for treatment of occlusive PAD, aneurysmal arterial disease, and venous occlusive disease.

Ischemic steal syndrome following arm arteriovenous fistula for hemodialysis

Abstract

Arteriovenous fistulae in the arm are commonly used for hemodialysis in end-stage renal disease. Although physiological steal with reverse flow in the artery distal to the fistula is common, hand ischemia or infarction are rare. The ischemic steal syndrome (hand or forearm ischemia) is usually a result of arterial disease proximal or distal to the fistula and/or poor collateral supply to the hand. The diagnosis is primarily clinical; however, markedly reduced digital pressures and pulse volume recordings support the diagnosis. Management requires imaging for focal stenoses or disease in arteries proximal and distal to the fistula from the aorta to the hand. We present a case caused by subclavian artery occlusion that was initially missed due to focusing investigation only on the fistula. We describe the percutaneous treatments and surgical revisions that attempt to restore flow to the hand without compromising the fistula.

Prevalence and treatment of proximal left subclavian artery stenosis in patients referred for coronary artery bypass surgery

The left internal mammary artery (LIMA) is currently used in most coronary artery bypass graft (CABG) surgeries due to excellent long-term patency. Left subclavian artery stenosis (SAS) proximal to the LIMA origin can cause a steal syndrome leading to myocardial ischemia or LIMA failure. We retrospectively evaluated the records of 608 consecutive patients referred for CABG at our institution between October 1, 2004 and October 1, 2006 and identified 226 patients (37%) who underwent left subclavian angiography immediately after diagnostic coronary angiography. Significant left SAS was found in 6 of those 226 patients (2.7%). Subclavian angiography did not result in any complications. All left SAS lesions were successfully stented, followed by CABG surgery (using the LIMA artery) after 22+/-7 days. Left subclavian angiography in patients referred for coronary artery bypass surgery has low risk and may identify a small proportion of patients with significant proximal left SAS. Stenting of proximal left SAS can be accomplished before CABG with low risk and excellent short-term outcomes.

Endovascular treatment of vertebral artery-origin and innominate/subclavian disease: indications and technique

Approximately 20% to 40% of patients who have cerebral vascular disease have a vertebral artery-origin stenosis. Atherosclerotic lesions of vertebral arety origin are a potential cause of posterior circulation ischemia, which can be disabling or deadly. Endovascular treatment of vertebral artery-origin and innominate/subclavian artery stenosis has changed in the last 15 years. Surgery usually is successful technically; however, it is also associated with high rates of procedural and periprocedural complications. New techniques and technologies that can be used in the treatment of such lesions are being developed. In this article, the authors discuss the indications, technical aspects, and long-term results of angioplasty and stenting of these vessels.

Doppler ultrasonography in suspected subclavian artery obstruction and in patient monitoring after subclavian stenting

PURPOSE

Subclavian or innominate artery (SIA) stenosis affects up to 5% of patients referred to coronary bypass grafting; it is symptomatic in less than half of these. This study aimed to assess the Doppler ultrasonography (DU) findings in SIA obstruction and patients' follow-up after percutaneous angioplasty (PTA).

METHODS

The study enrolled 118 patients (68 men, 50 women), aged 61.3 +/- 8.7 years, with suspected SIA obstruction, in whom peak systolic velocity (PSV) in the SIA and subclavian steal grade were assessed on DU and verified by quantitative angiography (QA). Serial follow-up DU was performed in patients treated with PTA.

RESULTS

Grade I-III of subclavian steal from the vertebral artery (VA) was found in 89.8% of patients. In the remaining 10.2% only a PSV increase in the SIA was observed. QA confirmed the presence of SIA obstruction in all patients (stenosis grade: 80.9 +/- 17.3%). In patients with one-sided SIA obstruction, the ultrasonographic steal grade correlated with the QA stenosis grade (p < 0.001, r = 0.648). Lack of subclavian steal was noted in the case of distal subclavian stenosis, VA obstruction, VA originating from the aortic arch, and bilateral SIA obstruction. Successful PTA was performed in 77 of 83 patients referred to that procedure. PSV was reduced from 4.4 +/- 1.2 (2.2-6.5) m/sec to 1.34 +/- 0.51 (0.5-2.5) m/sec and flow in the VA was normalized. During the mean follow-up time of 24.7 +/- 15.6 months, there was a gradual increase in the in-stent PSV as well as gradual VA flow alterations, resulting in symptom recurrence. More than a twofold PSV increase, compared with the post-PTA values, was an indicator of restenosis in 11 of 12 patients.

CONCLUSIONS

Careful DU evaluation enables the recognition of SIA obstruction in all patients. Ninety percent of them have subclavian steal correlating with the stenosis grade. Restenosis can be reliably detected with DU based on in-stent PSV and VA flow alterations.

Diagnosis and Management of Subclavian Artery Stenosis Prior to Coronary Artery Bypass Grafting in the Current Era

There are several approaches to managing subclavian artery stenosis (SAS) prior to coronary artery bypass grafting (CABG) with an intended internal thoracic artery (ITA) graft to the left anterior descending (LAD) artery. We herein review the incidence of and various diagnostic modalities for detecting SAS. Published relevant clinical studies from the interventional cardiovascular and cardiac surgical literature are summarized. Particular emphasis is placed on the efficacy of various approaches to the patient diagnosed with SAS prior to CABG. Stenting the subclavian artery prior to bypass surgery and using an in situ ITA is compared to using the ITA as a "free" graft. The incidence of restenosis after subclavian artery angioplasty or stenting is not trivial and has been reported to occur at a rate of 6% to 21%; however, the average rate of restenosis with stenting appears to be in the mid-teens. Subacute subclavian stent thrombosis or occlusion is exceptionally rare, suggesting that a percutaneous approach to SAS is reasonable prior to CABG. For patients requiring emergent revascularization, placement of a free ITA graft to the LAD appears to be a safe and durable treatment as patency rates are comparable to that of an in situ LITA to the LAD. In summary, although no randomized clinical trials address the optimal management of SAS prior to CABG, both percutaneous and surgical options appear to be safe and reasonably durable.

Vertebral artery embolic protection via ipsilateral brachial approach during left subclavian artery angioplasty and stenting--a case report

The purpose of this report is to explore angioplasty and stenting with cerebral embolic protection as a salvage procedure for a compromised carotid-subclavian bypass in the presence of antegrade vertebral artery flow. A 76-year-old woman with a carotid-subclavian bypass presented with graft infection. Failure of medical therapy to treat the infection prompted surgical removal of the graft. The native subclavian artery was still patent, but a severe complex proximal stenosis was present with antegrade flow into the left vertebral artery. Angioplasty and stenting of the subclavian artery was performed with cerebral protection achieved by positioning a FilterWire EX in the left vertebral artery via the left brachial artery approach. Deployment of a filter device in the vertebral artery via the brachial or radial approach can provide embolic protection without interfering with the subclavian artery stenting. The successful treatment of the subclavian artery enabled the complete removal of the infected graft without need for major vascular reconstruction.

Endovascular Treatment of Peripheral Vascular Disease

An estimated 10 million people in the U.S. have symptomatic peripheral arterial disease (PAD); 20 to 30 million have asymptomatic PAD. The prevalence of intermittent claudication increases with age, affecting >5% of patients over 70. The incidence of claudication doubles or triples in patients with diabetes. As people grow older, symptoms from peripheral vascular disease increasingly limit daily activity. Until recently, vascular surgical procedures were the only alternative to medical therapy in such patients. Today, advances in minimally invasive percutaneous interventions have made endovascular procedures the primary modality for revascularization in most patients. Compared with open surgical procedures, endovascular interventions offer comparable or superior long-term rates of success with very low rates for morbidity and mortality. Furthermore, most of these interventions are performed on an outpatient basis, reducing hospital stays considerably. In this monograph we discuss current endovascular interventions for treating occlusive PAD, aneurysmal arterial disease, and increasingly common venous occlusive diseases.

Endovascular Treatment of Supra-Aortic Extracranial Stenoses in Patients with Vertebrobasilar Insufficiency Symptoms

PURPOSE

Stenoses and thromboses of vessels feeding the vertebrobasilar territory can evoke serious disturbances including ischemic stroke. We present our experience of endovascular interventions for patients with signs of vertebrobasilar insufficiency (VBI) resulted from subclavian, vertebral and brachiocephalic arterial stenoses.

METHODS

Twenty-one patients (10 men) aged from 35 to 84 years (mean 64.3 years) with symptoms compatible with VBI underwent balloon angioplasty and stenting of subclavian (SA), innominate (IA) and vertebral (VA) arteries. Procedures were done by radiologists experienced in systematic stenting of the lesions. VBI was manifested by persistent signs in 15 patients, and by transitory ischemic attacks in the posterior circulatory territory in 4 (19%). Two patients (10%) experienced ischemic strokes (in the vertebrobasilar circulation in both cases). In 3 patients (14%) VBI was accompanied by upper limb vascular insufficiency symptoms. All cases were resistant to medical treatment. A neurologist assessed complaints, initial VBI signs and their alteration after intervention in all patients. Outcomes were measured with the 5-point scale suggested by Malek et al.: (1) excellent result (asymptomatic, no neurologic deficits and no symptoms of vertebrobasilar ischemia); (2) good (no neurologic deficits, at most one transient episode of vertebrobasilar ischemia over a period of 3 months after treatment); (3) fair (minimal neurologic deficit and at most one transient episode per month of vertebrobasilar ischemia); (4) poor (no improvement compared with neurologic status before treatment and/or persistent symptoms of vertebrobasilar ischemia); (5) death (regardless of cause). Endovascular treatment was performed for SA stenosis in 15 patients, for SA occlusion in 2, for IA stenosis in 2, and for VA stenosis in 2. There were 15 cases of atherosclerosis, 2 of aortoarteritis, 4 of proximal SA kinking. SA and IA stenoses ranged from 60% to 100% (mean 74.5%), VA stenoses were 90% in both cases.

RESULTS

Initial technical success was achieved in 96% of cases. There were no postprocedural complications or deaths. During 6-36 months (mean 21.3 months) of follow-up all patients showed improvement in VBI symptoms or upper limb ischemia. Within 36 months after the procedure outcomes were estimated as excellent and good in 13 patients (76%) and poor in 2 (12%), the last being attributed to atherosclerosis progression in other vascular areas. Restenosis in the stented area has developed in 1 patient (6%).

CONCLUSIONS

Balloon angioplasty and stenting of extracranial vertebrobasilar arterial stenoses appeared to be effective in endovascular treatment of medically resistant VBI. Further investigations are required to clarify the role of subclavian artery kinking in VBI development and indications for various methods of its correction.

Determinants of immediate and long-term results of subclavian and innominate artery angioplasty

BACKGROUND

Percutaneous angioplasty (PTA) is widely used in the treatment of subclavian/innominate artery obstruction, but factors of long-term PTA outcome are poorly understood. Our aim was to evaluate the efficiency of PTA on symptom resolution and identify determinants of long-term outcome.

METHODS AND RESULTS

Seventy-six lesions were treated in 75 patients (58.7% men) aged 60 +/- 8.5 years. PTA was successful in 70 (93.3%) patients, including 58/58 (100%) stenotic lesions and 13/18 (72.2%) occlusions. The mean stenosis grade (QCA) was reduced from 78.9% +/- 16.6% to 13.5% +/- 10.7% (P < 0.01). A great majority of lesions (87.1%) were stented. In 5 (7.1%) high-risk lesions a proximal or distal neuroprotection system was used. There were no strokes or embolic events. Minor complications occurred in 7 (9.3%) cases. Fifty-seven (89%) of 64 symptomatic patients had complete symptom resolution. The mean follow-up was 24.4 +/- 15.5 months (up to 66 months). Ten restenoses (15.6%), including 9 (13.8%) in-stent restenoses and 1 (16.7%) restenosis after balloon angioplasty, were diagnosed in 64 patients and followed up for at least 6 months. Nine symptomatic restenoses were successfully treated with repeated angioplasty. Cox multivariable analysis revealed the following independent predictors of restenosis: implantation of more than one stent (P = 0.005), low stent diameter (P = 0.088), and postprocedural systolic blood pressure difference between upper extremities (P = 0.044).

CONCLUSIONS

PTA is a safe and effective method for the treatment of the subclavian/innominate artery obstruction and leads to symptom resolution in majority of patients. Restenosis is not frequent and it can be effectively treated with repeat angioplasty. Low stent diameter, implantation of two stents, and upper limb systolic blood pressure difference are independent predictors of restenosis.

Duplex Ultrasonography of Vertebral and Subclavian Arteries

Duplex ultrasonography of the vertebral artery is an integral part of extracranial cerebrovascular screening and provides noninvasive diagnostic clues for subclavian or vertebral artery stenosis. This review describes technique for the ultrasound examination of the vertebral and subclavian arteries. Duplex images from various patients are used to illustrate a spectrum of hemodynamic changes that occur in the vertebral artery Doppler signal caused by subclavian artery stenosis and subclavian-vertebral steal.

Endovascular treatment of the subclavian artery: Stent implantation with or without predilatation

The endovascular treatment of subclavian artery (SA) lesions is less invasive than open surgical repair, with a low rate of complications. We report our experience in 89 subclavian obstructive lesions (n = 86) treated with stenting: 76 (85.3%) stenoses and 13 (14.6%) total occlusions. The left side was most frequently involved (83.1%), localized at the prevertebral segment in 91%. Technical success was obtained in 83 (93.3%) cases, 100% in stenotic lesions and 53.8% in total occlusions. There were nine global complications (10.1%): five (5.6%) at site of puncture, two distal embolization (2.2%), and two (2.3%) major events. The long-term follow-up was 3.51 +/- 1.98 years, during which time 13 (16.8%) restenoses and 2 (2.6%) reocclusions were noted. Subgroup analysis of patients with stenting after predilatation versus direct stenting technique showed in-hospital complications only in the first group, with a restenosis rate of 28.5% vs. 4.7%, respectively (P = 0.003). We consider stenting for SA obstructive lesions the first therapeutic option.

Primary Stenting of Subclavian and Innominate Artery Occlusive Disease: A Single Center?s Experience

PURPOSE

To review immediate and midterm results of primary stenting for innominate and subclavian artery occlusive lesions.

METHODS

Retrospective data were collected from 48 consecutive symptomatic patients (27 men and 21 women, median age 64 years) having 49 subclavian and innominate artery lesions treated with stenting. Of the patients 52% had concomitant ischemic heart disease, and 30% had carotid and/or vertebral artery disease. Indication for treatment was vertebrobasilar insufficiency (VBI) in 16.6% of the patients; upper limb ischemia (ULI) in 31.3%; VBI and ULI in 12.5%; transient ischemic attack in 16.7%; angina in 12.5% before or after left internal mammary artery-to-coronary artery bypass grafting; and leg claudication in 10.4% before or after axillofemoral bypass grafting. Balloon-expandable stents were used in 44 lesions and self-expandable stents in 5 lesions. In total, 53 stents were placed in 48 patients.

RESULTS

Technical success was 96%, and clinical success 94%. We encountered four complications (two puncture site hematomas, one distal hand embolization and one transient cerebral ischemia). Two patients died within 30 days from other causes, and seven patients were lost to follow-up. Mean follow-up time was 16.7 months (range 0.3 to 68.2). Five patients had recurrent lesions treated by surgical (n = 2) or endovascular (n = 3) means. Cumulative primary patency rate was 91.7% and 77% at 12 and 24 months, respectively. Cumulative secondary patency rate was 96.5% and 91.7% at 12 and 24 months, respectively.

CONCLUSION

Stenting of subclavian and innominate artery lesions resulted in immediate resolution of patients' symptoms with durable midterm effect and few complications in a larger patient group with serious comorbid conditions.

Crush stenting of bifurcational left subclavian-vertebral artery stenosis

Left internal mammary artery (LIMA) has the best long-term patency in patients undergoing coronary artery bypass surgery. Stenosis of the proximal left subclavian artery (SA) may reduce flow to the LIMA, causing myocardial ischemia. We report a novel technique (crush stenting) for the treatment of a complex bifurcational left SA-vertebral artery (VA) stenosis in the presence of a patent LIMA bypass conduit. This technique limited plaque shifting, restored normal flow to all vessels, including the LIMA, and avoided devastating consequences of VA occlusion.

Subclavian artery stenting: factors influencing long-term outcome

This study provides extended follow-up of a nonrandomized series of symptomatic patients who underwent subclavian stent-supported angioplasty (SSA) with emphasis on preprocedure factors that may have influenced outcome. The endpoints of mortality and restenosis were analyzed using backward stepwise logistic regression with the following clinical variables: coronary artery disease, hypertension, hyperlipidemia, smoking, diabetes mellitus, chronic obstructive pulmonary disease, chronic renal insufficiency/failure, and hypothyroidism. Restenosis is reported based on prospective serial noninvasive studies and/or angiography. Mortality was evaluated by retrospective database review and inquiry to the State Department of Health and Human Services' statistical registry in patients who were lost to follow-up. Over a 9-year period (mean follow-up, 36.1 +/- 30.4 months; maximum observation, 109.5 months), 101 stents were placed in 91 consecutive patients (37 male, 54 female). The mean age at intervention was 62.03 +/- 9.3. The procedure was technically successful in 89 patients 97% (mean pre- and postoperative stenosis and pressure gradients were 90.2% +/- 9.4% vs. 3.7% +/- 6.6%, P < 0.001, and 59.9 +/- 35.2 vs. 0 mm Hg, P < 0.001, respectively), with 13 minor complications and no immediate major complications. One patient died of unrelated causes within 30 days. Per Kaplan-Meier method, for years 1 through 5, the rates of overall patency were 96%, 91%, 86%, 77%, and 72%; likewise, overall patient survival was 93%, 88%, 8%4, 81%, and 76%. No clear predictors for restenosis were discovered, although a trend toward higher recurrence was noted in women (18.5% in female vs. and 8.6% in male; P > 0.05), but the same were less likely to die during follow-up (P > 0.001). Also, the presence of hypothyroidism (P = 0.004) and increasing age (P = 0.068) were positively correlated with all-cause mortality. This study suggests that SSA is predictable, safe, and durable. The diagnosis of symptomatic subclavian disease is of prognostic importance, with age and male gender representing important predictors of all-cause long-term mortality. The strong association of increased mortality with hypothyroidism is difficult to discard and raises the question of a yet to be described thyroid steal phenomena.

Extracranial revascularization therapy: Angioplasty and stenting

Beginning with simple balloon angioplasty, minimally invasive revascularization techniques have progressed to the use of metallic stents for improved immediate and long-term results. Stent-supported angioplasty now offers a therapeutic option for those individuals ineligible for surgical revascularization of stenotic atherosclerotic lesions and who have failed maximal medical therapy. However, the clinical equivalence, or possibly even superiority, of angioplasty of the extracranial carotid and vertebral arteries in atheromatous occlusive disease over surgical revascularization has yet to be determined in ongoing randomized controlled trials. Additionally, endovascular techniques offer treatment for a variety of nonatherosclerotic disease affecting the extracranial arteries, such as inflammatory, radiation-induced, and postsurgical strictures; acute intimal dissection; traumatic and spontaneous arteriovenous fistulas; and aneurysms or pseudoaneurysms. For certain disease entities at high risk for surgical complications, endovascular procedures have gained preference as the therapeutic modality of choice, yet lacking controlled trials providing evidence for noninferiority against surgical approach. Continued innovation and refinement of endovascular technology and techniques will further improve technical success, reduce procedure-related morbidity, and broaden the endovascular therapeutic spectrum for extracranial and intracranial cerebrovascular disease.

The significance of subclavian artery injection prior to surgical myocardial revascularization

Successful arterial revascularization using the internal thoracic artery is dependent on unobstructed inflow through the subclavian artery. Systematic physical examination should discover subclavian stenosis; however, simple routine injection into the orifice of the subclavian artery during the diagnostic catheterization may avoid a catastrophic outcome.

Upper extremity arterial disease

Upper extremity arterial disease is much less common than lower extremity involvement and typically presents as arm claudication, Raynaud's syndrome, rest pain, ischemic ulcerations, or gangrene. The disease can reflect an underlying systemic disorder. In addition to clinical examination, diagnostic studies include noninvasive vascular studies, serologic, immunologic, and hematologic studies (when indicated), and selective arteriography. Atherosclerotic disease is the most common cause of large vessel obstruction, but it can also cause small vessel obstruction by atheromatous embolization or thromboembolism. Treatment varies from pharmacological therapy for vasospastic and vasculitic syndromes to operative approaches for endarterectomy or bypass of focal lesions. Angioplasty and stent techniques also can provide an effective treatment option.

Recent advances in peripheral angioplasty and stenting

Utilization of percutaneous interventions for arterial and venous occlusive lesions continue to increase. With the progression of the technology supporting these therapeutic measures, the results of these interventions may be expected to improve. In general, a comparison of techniques for revascularization demonstrates similar initial technical success rates for surgery and percutaneous transluminal angioplasty. Angioplasty is often associated with lower procedural morbidity and mortality rates. Conversely, surgery frequently provides greater long-term patency. Late failure of percutaneous therapies may often be treated successfully with reintervention, however. The continued accumulation of experience with PTA and stenting will ultimately define its role in the management of occlusive disease.

Angioplasty and stenting for total symptomatic atherosclerotic occlusion of the subclavian or innominate arteries

Bypass grafting is considered the treatment of choice for occlusions of supraaortic vessels. Percutaneous transluminal angioplasty (PTA) is a well-established treatment for patients with subclavian stenosis, but its efficacy in total subclavian or innominate occlusions is so far not well established. Since 1995, we have carried out 9 PTA revascularizations in 9 patients with total symptomatic atherosclerotic occlusion of supraaortic vessels. The technical success rate was 100%, without any major (death or stroke) or minor complications. In the follow-up period (mean 37.4 months), 1 patient had a symptomatic left internal carotid artery occlusion and an asymptomatic occlusion of the treated subclavian artery. In expert hands, stenting-PTA should be considered as the primary therapeutic option.

Impaired flow in left internal mammary artery grafts due to subclavian artery stenosis

We report two cases of patients with left internal mammary artery (LIMA) grafts impaired by proximal stenosis of the subclavian artery. The functional impact of the subclavian lesions was investigated using flow-wire. The hemodynamic relevance of the lesions could be documented with the functional flow measurements in both instances. The relevance of preoperative evaluation of the subclavian artery is emphasized when it is planned to use the LIMA as coronary bypass. Moreover, the case reports indicate that percutaneous intervention of the subclavian artery is an effective treatment modality to restore adequate flow in the LIMA.

Transcatheter interventions for the treatment of peripheral atherosclerotic lesions: part I

Transcatheter endovascular procedures are increasingly used to treat symptomatic peripheral atherosclerosis. This two-part review identifies the existing evidence supportive of the application of transcatheter treatments for peripheral atherosclerotic lesions. The first part addresses the treatment of obstructive lesions that cause limb claudication and critical ischemia, renovascular hypertension and azotemia, and mesenteric ischemia. Studies were identified via a search of MEDLINE (January 1993 through April 1999) and reference lists of identified articles. When multicenter prospective randomized trials or other high-quality studies were unavailable, a preference was given to studies with at least 50 patients per treated group and a minimum mean follow-up duration of 6 months. Data presented in tables are proportionally weighted averages from included studies. For each application, the authors assessed the quality of evidence (QOE; efficacy, safety, and, where available, cost-effectiveness) and made recommendations with appropriate caveats. There is higher QOE supporting the more established treatments such as lower limb percutaneous transluminal angioplasty (PTA) with stent placement and thrombolysis. Treatments such as renal artery PTA and stent placement and mesenteric and brachiocephalic PTA are in wide use, but high QOE supporting general application is lacking. Blanket recommendations based on established efficacy and cost-effectiveness cannot be made. However, the use of transcatheter therapies can be supported in specific circumstances based on an expected reduction in procedure-related morbidity and/or mortality rates. It is hoped that the identification of deficiencies in the literature will inform and inspire critically needed research in this area.

Subclavian artery stenting: Immediate and mid term clinical follow-up results

BACKGROUND: Intravascular stents are increasingly being used to treat subclavian artery obstructive disease. This study aimed to assess the immediate and mid-term clinical outcome of subclavian artery stenting. METHODS AND RESULTS: Total occlusion of the subclavian artery was seen in 7 (28%) out of the 25 consecutive patients treated for subclavican artery stenosis. Mean lesion length was 14 +/- 4.3 mm. The mean preprocedure diameter stenosis was reduced from 83.2 +/- 14.9% to 9.6 +/- 5.4% postprocedure. Procedural success was achieved in all patients. Clinical follow-up was obtained in all patients. The initial success was maintained at follow-up (mean = 12 +/- 4 months) in 24 (96%) patients. Recurrence of symptoms occurred in 1 (4%) patient who had an angiographically documented restenosis four months after the procedure. It was successfully redilated. CONCLUSION: Stenting for subclavian artery obstructive disease is safe, technically feasible and has favorable clinical outcomes. It may be considered as the therapy of choice for subclavian artery obstructive disease.