Gustav Eles

Endovascular Stents for Carotid Artery Occlusive Disease

Purpose: To study the feasibility and safety of endovascular stenting of cervical carotid artery stenosis. Methods: Between April 1994 and May 1997, 108 consecutive patients (58 men; mean age 70.1 years) with ≥ 70% carotid stenosis were treated with percutaneous stent implantation under a protocol that featured independent neurological review. Forty-four percent were asymptomatic. Over half the lesions (59%) were in the internal carotid artery; the mean stenosis was 86%. Palmaz stents were implanted without cerebral protection following preliminary balloon dilation; two Wallstents were used in long lesions. Results: Carotid stents were successfully placed in 108 of 114 (95%) lesions. Of the 6 technical failures, 5 were access related and 1 was due to seizures during balloon dilation. Two major (1.8%) and 2 minor (1.8%) strokes occurred (3.7% stroke rate for 108 patients; 3.5% in 114 procedures), all in symptomatic patients, one of whom died. There were 5 (4.4%) transient ischemic attacks and 2 (1.8%) brief seizure episodes during dilation. One patient died of a cardiac event on day 20. The all stroke or death rate was 5.3% based on 114 arteries at risk (5.6% in 108 patients). In the mean 6-month follow-up (range 1 to 36) of 97 eligible patients, 3 (3.1%) died from unrelated causes. There was 1 restenosis (1.0%) from a stent compression, which was successfully redilated. There were no neurological sequelae, cranial palsies, or cases of stent or vessel thrombosis in follow-up. Conclusions: The use of stents in the treatment of cervical carotid occlusive disease appears feasible, effective in the short term, and without excessive risk of periprocedural stroke.

Carotid Artery Stent Placement—Ready for Prime Time?

FEW medical debates have been more controversial than that between carotid stent placement and carotid endarterectomy (CEA). This is understandable considering that CEA, after the published report of the North American Symptomatic Carotid Endarterectomy Trial (NASCET) trial (1), represented the gold standard for managing carotid artery occlusive disease (1,2). The NASCET trial (1) was initiated in 1988 and completed in 1991. Patients with symptomatic internal carotid artery stenosis greater than 70% were randomized to receive either CEA or medical management. The periprocedural stroke and death rate in the trial was 5.6%. A cumulative 2-year stroke rate of 9% in patients who underwent CEA, versus 26% in patients who underwent medical management, was noted. Surgeons who participated in the trial were carefully given credentials based on a perioperative stroke and death rate lower than 6% in their most recent 50 consecutive patients who had undergone CEA. What is less understood in the NASCET trial is the 7.6% incidence of cranial nerve palsy and the significant neck hematoma rate of 5.5% (1). In contrast to the high-risk carotid artery stent placement registries and the high-risk randomized clinical Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy (SAPPHIRE) trial, NASCET and the Asymptomatic Carotid Atherosclerosis Study (ACAS) trial were trials involving patients at low risk, without significant comorbidity (3,4). Patients with contralateral occlusion comprised the only high-risk subset within the NASCET trial and, in those patients, a perioperative stroke and death rate of 14% was described (1). In the European Carotid Surgical Trial, a perioperative stroke and death rate of 7.1% and a cranial nerve palsy rate of 6.4% were described (5). Chaturvedi et al (6), in a multicenter study, reported an 11% stroke and death rate after CEA, which was believed to represent an accurate account of “real world” endarterectomy results. During this same period, single institutional centers began reporting their data after carotid stent placement in patients in high-risk subsets (7–11). Most of these patients would not have been eligible for enrollment in either the NASCET or ACAS studies. In our experience, only 9% of 540 patients who underwent stent placement would have been eligible for enrollment in either of the NASCET or the ACAS studies (8). However, the Food and Drug Administration declared that carotid stent placement represented a high-risk procedure that would require institutional review board approval and a Food and Drug Administration–approved Investigational Device Exemption before proceeding. It was not until Medicare approved reimbursement for carotid stent placement performed at an approved trial site that carotid stent placement became an acceptable alternative to CEA in a selected high-risk subset of patients.

Carotid artery revascularisation in high-surgical-risk patients with the NexStent and the FilterWire EX/EZ: 3-year results from the CABERNET trial

Aims: To investigate long-term outcomes achieved in high-surgical-risk patients and other clinically-relevant subgroups after carotid stenting with the NexStent and Filterwire EX/EZ devices. Methods and results: CABERNET, a prospective, multicentre, single-arm trial, enrolled 454 patients with extracranial internal carotid artery stenosis (symptomatic ≥50%, n=110; asymptomatic >60%, n=344). Early outcomes at one year have been reported. The 3-year Kaplan-Meier estimated event rates were: 7.2%, all stroke; 2.8%, major stroke; 4.8%, ipsilateral stroke; 17.7%, all death; 7.1%, myocardial infarction; 4.4%, target vessel revascularisation. Asymptomatic patients had significantly fewer major strokes than symptomatic patients (1.9% vs. 5.7%, P=0.03) and patients <80 years had significantly fewer ipsilateral strokes than those ≥80 years (3.2% vs. 10.7%, P=0.002). Stroke outcomes did not differ significantly between patients with anatomical risk factors compared with those with comorbid medical risk factors. Conclusions: Long-term outcomes achieved in high-surgical-risk patients with the NexStent and Filterwire EX/EZ devices are favourable. Outcomes may be better in asymptomatic patients or those younger than 80 years of age. These data will be helpful in estimating short-term risks of carotid stenting and balancing these risks against the long-term benefit of stroke prevention.

Balloon Aortic Valvuloplasty for Aortic Stenosis Using a Novel Percutaneous Dilation Catheter and Power Injector

Calcific aortic stenosis is the most common valvular heart disease in the Western world. Although definitive treatment is valve replacement, many patients are not replacement candidates due to high surgical risk from older age and comorbid illness or lack of desire for a surgical or replacement procedure. Percutaneous balloon aortic valvuloplasty (BAV) is an option for palliative treatment in nonsurgical patients, although this procedure is complicated during the immediate postprocedure period by bleeding requiring transfusion for about 1 in 5 patients and subsequent restenosis. This report describes BAV using a smaller profile balloon designed to withstand higher pressures, rapidly inflated with a power injector. Twenty consecutive high-risk patients with severe aortic stenosis were treated. In all cases, New York Heart Association (NYHA) class improved from IV before BAV to I or II at 30 days follow-up. Six-month posttreatment follow-up data were available for 19 of 20 patients: 15 patients were either NYHA class I or II, 1 patient was class III, and 3 deaths occurred unrelated to aortic stenosis. One patient was lost to follow-up. Average systolic gradient peak-to-peak pressure decreased by 40.0% (range 18.0-70.0%) and mean gradient decreased by 30.0% (range 13.7-70.8%). Aortic valve area increased from 0.59 ± 0.16 cm(2) to 0.92 ± 0.23 cm(2), representing a mean increase of 30.0% (range 7.8%-58.2%). There were no significant bleeding complications. The only procedural complication was a single case of pericardial tamponade. There were no other complications during the first 24 hours post-BAV. These data support that the reported BAV technique may offer an effective alternative for patients with severe aortic stenosis who are not surgical candidates or prefer to avoid aortic valve replacement.