Carotid angioplasty and stenting under protection: advantages and drawbacks.

Carotid stenosis is responsible for approximately 30% of strokes, and carotid endarterectomy is considered to be the gold-standard treatment. Carotid angioplasty and stenting (CAS) has been proposed as an alternative to surgery but the risk of neurological complications and brain embolism remains the major drawback to this procedure. Embolic protection devices (EPDs), which retain particles and debris generated during the procedure, have been proposed to reduce the frequency of neurological complications. Three types of EPD have been developed: distal occlusion balloon, distal filters and proximal protection devices. Preliminary clinical results indicate that the routine use of an EPD along with specifically designed flexible stents, increasing skills of the interventionist and appropriate drugs combine to reduce ischemic neurological complications and can achieve similar results to the best surgical series, particularly in high surgical risk patients. Recent prospective, multicenter controlled trials and registries evaluating CAS with EPD have demonstrated that the CAS results are, at least, not inferior to surgery for patients at high risk for surgery (Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy study) and in symptomatic patients (Stent Supported Percutaneous Angioplasty of the Carotid Artery versus Endarterectomy study). However, all protection devices are not equivalent and have some drawbacks. Advantages and disadvantages of each EPD will be analyzed in this review, allowing a good choice of the EPD depending on the patient and the lesion. Nevertheless, there is now a consensus among specialists to perform all CAS with EPD. EPDs have become an integral part of CAS and the routine use of EPDs seems beneficial, leading to a 60% reduction of brain embolisms.

Treatment of renal artery aneurysm with the multilayer stent.

PURPOSE: To describe a new type of stent consisting of a 3-dimensional (3D) braided tube made of 2 interconnected layers without any covering to treat a renal artery aneurysm. CASE REPORT: A 78-year-old hypertensive man with multiple comorbidities was incidentally found to have a large (28- x 30 mm) saccular aneurysm in the main right renal artery involving the inferior renal artery. Via a percutaneous femoral approach, a 6- x 30-mm Multilayer stent was deployed easily in front of the aneurysm neck covering the inferior renal artery. Blood flow inside the sac was immediately and significantly reduced. All the renal artery branches remained patent. Blood pressure returned to normal after the procedure. At 6 months, angiography showed complete shrinkage of the aneurysm wall; all the inferior renal artery branches remained patent. CONCLUSION: The 3D multilayer fluid modulating stent concept appears to be a viable alternative for renal aneurysm exclusion. A larger study is underway to evaluate this new stent in other peripheral aneurysms.

Renal angioplasty and stenting: long-term results and the potential role of protection devices.

Renal angioplasty and stenting have become the first treatments to be proposed to patients presenting with renal artery stenosis. The immediate technical success rate is high, with a low complication rate and good long-term patency. In most reports, renal stenting has been proven to improve blood pressure. However, despite good immediate- and long-term results, postprocedural deterioration of renal function is a concern, and may occur after renal artery angioplasty and stenting in 20 to 40% of patients, which limits the immediate benefits of this technique. Of the causes of this deterioration in renal function, atheroembolism seems to play an important role. Contrary to earlier beliefs that atheroembolization is not an issue during percutaneous catheter interventions, there is now mounting evidence that distal atherosclerotic debris commonly embolizes from lesions in many vascular territories during percutaneous interventions. Atheroembolism seems to be the root cause of many procedural complications wherever atherosclerotic lesions are treated. Distal embolization was first demonstrated in saphenous vein grafts and now, clinical data are proving that similar embolization and distal-organ complications also occur during catheter treatment in certain native coronary lesions, carotid stenting and renal artery stenting, demonstrating the role and efficacy of protection devices to reduce the incidence of end-organ complications. The same protection devices (protection balloon and filters) utilized for coronary or carotid procedures may be used to protect the kidney from atheroembolism. In this review, the authors discuss recently published data concerning the techniques and results of renal angioplasty and stenting procedures performed under protection, and evaluate the benefits of this technique on renal function and its role in the future. Indications for this technique need to be discussed.

Bilateral carotid angioplasty and stenting.

Bilateral carotid stenosis is generally treated by staged stenting procedure and rarely simultaneously due to concerns about hemodynamic impairment from stimulation of the carotid sinus baroreflex (severe bradycardia, hypotension) and the risk of cerebral hyperperfusion syndrome. Most of the accounts of bilateral carotid stenting are of small series. The aim of this study was to evaluate the feasibility and safety of simultaneous bilateral carotid angioplasty and stenting (CAS) in comparison with staged procedure. We retrospectively analyzed the procedural outcome and complications of bilateral CAS done between February 1995 and June 2004 in a consecutive series of 57 high-risk patients. Mean age was 64 +/- 9 years (male, 43; female 14). One hundred fifteen arteries were treated (one patient had bilateral internal carotid artery stenosis associated to an ostial common carotid artery stenosis). Thirty-nine patients were symptomatic (70%). Thirty-six patients had severe coronary artery disease. Seventeen patients underwent a simultaneous bilateral CAS (group 1), 40 in a staged manner (group 2). Among these 40 patients 10 were treated with a time interval of 24 hr, while the 30 other ones were treated with a time interval of 2 days to 2 months. A neuroprotection device was used in the last 42 patients. There was technical success in all patients and transient bradycardia and/or hypotension in 25 patients (44%). There was no prolonged bradycardia or hypotension. At 30 days, we observed in group 1 (simultaneous bilateral CAS) no transient ischemic attack (TIA), no minor stroke, one (5.8%) major stroke (hyperperfusion syndrome with brain hemorrhage leading to death in a patient under IIb/IIIa inhibitors), one myocardial infarction leading to death, and two (11.7%) death/stroke/myocardial infarction; in group 2 (staged procedure), two (5%) TIAs, no minor stroke, no major stroke, and one (2.5%) hyperperfusion syndrome with rapid recovery. Among the 10 patients treated with a time interval of 24 hr, we observed one TIA. Among carefully selected patients, bilateral CAS is feasible simultaneously or the day after, with a safety and complication rate comparable to that of large published series of CAS or endarterectomies in high-risk patients. Nevertheless, careful monitoring of the patient, blood pressure, and heart rate is mandatory to avoid complications related to hyperperfusion syndrome. Routine use of neuroprotection device and meticulous technique should improve the outcomes of bilateral CAS.

Renal angioplasty and stenting under protection: the way for the future?

The purpose of this study was to evaluate the feasibility and safety of renal artery angioplasty and stenting utilizing a distal protection device to reduce the risk of intraprocedural artery embolism and avoid deterioration of the renal function. Fifty-six hypertensive patients (32 men; mean age, 66 +/- 11.8 years; range, 22-87) with atherosclerotic renal artery stenosis (8 bilateral) underwent angioplasty and stenting with distal protection in 65 renal arteries (58 ostial lesions). Five patients had a solitary kidney, 18 a renal insufficiency. The lesion was crossed either with a GuardWire temporary occlusion balloon (n = 38), which was inflated to provide parenchyma protection or with a filter (EPI Filter; n = 26), or with Angioguard (n = 1), which allows a continuous flow. Generated debris was aspirated and analyzed. Blood pressure and serum creatinine levels were followed. Immediate technical success was 100%. All lesions except one were stented, either directly (43 ostial lesions) or after predilatation (22 ostial lesions). Visible debris were aspirated with the PercuSurge in all patients or removed with filters in 80% of the patients. Mean particle number and diameter were 98.1 +/- 60.0 per procedure (range, 13-208) and 201.0 +/- 76.0 microm (range, 38-6,206), respectively. Mean renal artery occlusion time was 6.55 +/- 2.46 min (range, 2.29-13.21) with the PercuSurge device. Mean time in situ (filters) was 4.25 +/- 1.12 min. Mean follow-up was 22.6 +/- 17.6 months (range, 1-47). Systolic and diastolic blood pressure declined from 169.0 +/- 15.2 and 104.0 +/- 13.0 mm Hg, respectively, to 149.7 +/- 12.4 and 92.7 +/- 6.7 mm Hg after the procedure. The mean creatinine level remains constant during the follow-up. At 6-month follow-up (45 patients), renal function did not deteriorate in any patient, whereas 8 patients with baseline renal insufficiency improved after the procedure. At 3 years (19 patients), renal function deteriorated only in 1 patient with renal insufficiency and in 1 patient treated for bilateral renal stenosis, one side without protection. These preliminary results suggest the feasibility and safety of distal protection during renal interventions to protect against atheroembolism and to avoid renal function deterioration. This technique's beneficial effects should be evaluated by randomized studies.

Clinical experience with the OptiMed sinus stent in the peripheral arteries.

PURPOSE: To retrospectively evaluate the performance of a new self-expanding nitinol stent in the treatment of lower limb arterial occlusive lesions. METHODS: The Sinus stent is a flexible, laser-cut device with good radiopacity and radial strength, allowing precise placement via a 7-F introducer, even in tortuous arteries. Over a 3.5-year period, 315 patients (254 men; mean age 64.9+/-10.8 years, range 39-93) had 403 lower limb lesions treated: 172 iliac (132 stenoses, 40 occlusions), 204 femoral (131 stenoses, 73 occlusions), and 27 popliteal (19 stenoses, 8 occlusions). The majority of patients (272, 86%) were in stage IIb of Fontaine's classification, 31 (10%) in stage III, and 12 (4%) in stage IV. Mean lesion lengths were iliac: 51.9+/-32.1 mm, femoral: 66.3+/-51.5 mm, and popliteal: 44.3+/-27.2 mm. Indications for stenting were 222 postdilation residual stenoses, 125 dissections, and 35 restenoses; 21 lesions were directly stented. RESULTS: Immediate technical success was 100%. Clinical success was 98%. The ankle-brachial index increased from 0.62+/-0.12 to 0.91+/-0.14. In 64 lesions, there were 3 early thromboses. Mean follow-up was 16.1+/-9.7 months (range to 40). There were 79 restenotic episodes: 14 iliac, 56 femoral, and 9 popliteal. Primary and secondary patencies for all lesions at 3 years were 72.5%+/-6.6% and 81.8%+/-5.9%, respectively. Stenoses demonstrated better patency than occlusions (primary: 78.0%+/-7.3% versus 60.2%+/-7.1%, p<0.001; secondary: 86.8%+/-6.1% versus 71.3%+/-6.7%, p<0.001). Men had better secondary patency at 3 years (83.7% versus 73.4%, p<0.05). For femoral lesions >8 cm, the results were acceptable for stenoses (66.7% primary and secondary patency at 3 years), but for lengthy occlusions, the restenosis rate was high (50.0% for occlusions versus 25.0% for stenoses, p<0.05). CONCLUSIONS: Angioplasty with the Sinus stent seems safe and effective in the treatment of peripheral arterial occlusive diseases, giving excellent results at the iliac and common femoral artery levels. Treatment results are better for stenoses than for occlusions. An occlusion length

Benefits of cerebral protection during carotid stenting with the PercuSurge GuardWire system: midterm results.

PURPOSE: To examine the possible beneficial effect of a new cerebral protection device based on balloon occlusion of the distal internal carotid artery (ICA) and debris aspiration for patients undergoing carotid artery stenting (CAS). METHODS: One hundred and eighty-four CAS procedures were attempted under cerebral protection using the PercuSurge GuardWire system in 167 patients (129 men; mean age 70.5 +/- 9.2 years, range 40-91)). The lesions were mainly atherosclerotic, and half (n = 93) were asymptomatic. Eighteen restenotic and 7 post-radiation stenoses were also treated. RESULTS: Technical success was 99.5%. All lesions were stented except 3 postangioplasty restenoses. Prophylactic occlusion during balloon dilation and stenting was well tolerated in 176 (95.7%) patients. Microscopic analysis of the aspirated blood showed different types of particles numbering between 7 and 145 per procedure with a mean diameter of 250 microm (56-2652 microm). The 30-day stroke and death rate was 2.7%: 3 periprocedural complications at <48 hours (1 major stroke and 2 transient ischemic attacks), 1 intracerebral hemorrhage at 3 days, and 1 death of cardiac failure at 3 weeks. CONCLUSIONS: This study yielded a favorably low rate of periprocedural embolic events comparable with standard CAS series. Protection devices may play an important role in future carotid interventions and expand the applicability of the procedure. Randomized studies (surgery versus CAS with and without cerebral protection) are awaited.