Carotid artery stenting: technical considerations

Abstract

Background and purpose: Carotid endarterectomy (CEA) is one of the most frequently performed operations in the United States. To offer patients a less invasive means to achieve the same goal, carotid artery stenting (CAS) is investigated as an alternative treatment to CEA.

Methods: Three hundred ninety patients underwent CAS, with 451 vessels treated. CAS was performed using a coaxial system with a 7F 90-cm sheath for predilation, stent placement, and stent dilation. Pretreatment antiplatelet therapy was administered. We currently practice same-day admissions and 23-hour discharges.

Results: The technical success rate was 98%. The 30-day mortality/morbidity rates were as follows: death, 1.7% (two [0.5%] neurologic and five [1.2%] systemic] major strokes, 0.9% (two of four were related to the intervention); minor strokes, 5.5%. Among 25 patients who suffered minor strokes, 14 achieved complete recovery. On an annual basis, the incidence of minor stroke declined from 6.8% (1994-1995), to 5.8% (1995-1996), 5.3% (1996-1997), and then 4% (1997-1998), with no major strokes or neurologic deaths occurring during the 1997 to 1998 period.

Conclusion: CAS is an effective treatment for carotid stenosis. With proper selection of patients and meticulous technique, complication rates compare favorably with those of CEA.

fig 1.

Angiograms from the case of an 80-year-old male patient with bilateral internal carotid artery stenosis. A, Angiogram shows 80% stenoses in the left internal carotid artery (ICA) (curved arrow). A 7F sheath (7F) was inserted into the left common carotid artery (LCCA). Distal, independent stenosis on the internal carotid artery (thick black arrow) can be seen. ECA, external carotid artery. B, Angiogram shows status after predilation (curved arrow) of the internal carotid artery with a 4-mm balloon over a 0.018-inch guidewire (white arrows). Spasm on the distal internal carotid artery can be seen. C, Angiogram obtained after the CAS control study. A 10 × 20 Wallstent was used, dilated with a 5 × 20 Symmetry balloon. Minimal residual spasm can be seen. Independent distal stenosis persists (wide black arrow).

fig 2.

Angiograms from the case of an 87-year-old female patient with occlusion of the right internal carotid artery and 65% symptomatic, ulcerated stenosis on the left common and internal carotid arteries. A, Angiogram of the innominate artery (IA) shows a 90-degree take-off of the left common carotid artery (LCCA), with more distal tortuosity. B, Anteroposterior projection angiogram of the left common carotid artery (LCCA) (5F catheter in the ostium). Sixty-five percent ulcerated stenosis (curved arrow) on the internal carotid artery (ICA) and on the common carotid artery (open arrow) can be seen. ECA, external carotid artery. C, Lateral projection. D, Anteroposterior projection angiogram of the left common carotid artery (LCCA), obtained through a 7F sheath placed in the distal left common carotid artery. By upward displacement of the bifurcation, kink (angled arrow) developed in the proximal internal carotid artery. 7F, distal tip of the 7F sheath; ECA, external carotid artery; open arrow, stenosis in the distal left common carotid artery; curved arrow, ulcerated stenosis in the internal carotid artery. E, Lateral projection. F, Anteroposterior projection angiogram of the left common carotid artery (LCCA), obtained after CAS was performed. A 10 × 20 Wallstent was used, dilated with a 5.5 × 20 Symmetry balloon. The 7F sheath is removed; the 5F catheter is in the ostium of the left common carotid artery. Open curved arrow, previous location of the ulcerated stenosis on the internal carotid artery. G, Lateral projection.