Endovascular treatment of severe symptomatic stenosis of the internal carotid artery: early and late outcome

Carotid Stenting for Radiation-Induced Extracranial Carotid Artery Occlusive Disease: Efficacy and Midterm Outcomes

Purpose:

To investigate the immediate and midterm results of carotid stenting for severe radiation-induced extracranial carotid artery disease.

Methods:

Between April 1998 and May 2002, 16 patients (15 men; mean age 64±8 years, range 48–72) presented with 18 severe radiation-induced carotid stenoses in the internal carotid artery (n=3), common carotid artery (n=7), and both vessels (n=8). Thirteen (76%) patients were symptomatic; the mean degree of carotid stenosis was 85%±10% (range 70%–95%). An independent neurological specialist assessed perioperative neurological complications before and after treatment. The patients were followed prospectively for at least 12 months by clinical examination and serial duplex ultrasound scanning. Restenosis was defined as a diameter reduction >50%.

Results:

Of 18 stent procedures attempted (2 staged), 1 was abandoned owing to failure to pass the guidewire across a tight lesion (94% technical success by intent to treat). In the 17 successfully completed procedures, 17 Wallstents and 4 SMART stents were deployed with satisfactory anatomical results. One postoperative stroke occurred as a result of thromboembolism to the ipsilateral middle cerebral artery and led to hospital death (5.9% combined stroke and death rate). One transient ischemic attack occurred (11.6% neurological event rate). With a median 30-month follow-up (range 5–55), 3 (17.6%) recurrent stenoses (>50%) were detected on duplex scan; 1 repeat angioplasty was performed. No new neurological event has been detected.

Conclusions:

Carotid stenting may be performed in patients with irradiation-induced carotid stenosis with acceptable risks and midterm durability.

Usefulness of Early Stenting for Symptomatic Extracranial Carotid Stenosis

BACKGROUND

While carotid angioplasty and stenting (CAS) have become an established procedure, outcomes of early CAS for symptomatic extracranial carotid stenosis (SECS) remain poorly understood. The present study aimed at determining the effectiveness of early CAS in SECS.

METHODS

Herein, 224 SECS patients underwent elective CAS between January 2008 and June 2015. The study population was stratified based on the time from symptom onset to the procedure (early CAS group: within 14 days; delayed CAS group: later than 14 days). Subgroup analysis (chi-square test, Mantel-Haenszel chi-square test, and analysis of covariance) evaluated the demographics, incidence of periprocedural thromboembolic complications, cerebral hyperperfusion syndrome (CHS), intracranial bleeding, and treatment outcomes on the modified Rankin Scale (mRS).

RESULTS

Symptomatic thromboembolic complications and CHS were noted in 2.68% and 0.89% of patients, respectively. The initial National Institutes of Health Stroke Scale (NIHSS) score was significantly higher in patients who underwent early CAS than in those who underwent delayed CAS (2.50 ± 3.97 vs. 0.97 ± 2.08, P = 0.001). After adjusting for age, duration of preprocedural dual antiplatelet therapy, initial NIHSS score, and preprocedural NIHSS score, the groups did not differ significantly regarding the incidence of symptomatic thromboembolic complications (P = 0.195), incidence of CHS (P = 0.950), incidence of intracranial bleeding (P = 0.970), 30-day mRS score (P = 0.124), and mRS score at final follow-up (P = 0.132).

CONCLUSIONS

For SECS patients who cannot undergo early carotid endarterectomy, early CAS is effective and safe if selectively indicated considering disease severity. Early and delayed CAS provide comparable mRS scores, incidence of symptomatic thromboembolic complications, CHS, and intracranial bleeding.

Poul Erik Andersen's radiological work on Osteochondrodysplasias and interventional radiology

Poul Erik Andersen is a Professor and Interventional Radiologist at the University of Southern Denmark, Odense and Odense University Hospital, Denmark. His innovative and expertise is primarily in vascular interventions where he has introduced and developed many procedures at Odense University Hospital. His significant experience and extensive scientific work has led to many posts in the Danish Society of Interventional Radiology, the European Society of Radiology and the Cardiovascular and Interventional Radiological Society of Europe, where he is a fellow and has passed the European Board of Interventional Radiology - The European qualification in Interventional Radiology.

Differential effects of carotid artery stenting versus carotid endarterectomy on external carotid artery patency

PURPOSE

To determine the effect of stent coverage of the external carotid artery (ECA) after carotid artery stenting (CAS) compared to eversion endarterectomy of the ECA after carotid endarterectomy (CEA).

METHODS

The records of 101 CAS and 165 CEA procedures performed over 2 years were reviewed. Duplex velocities and history and physical examinations were taken prior to the procedure, at 1 month, and at 6-month intervals subsequently. CAS was performed by extending the stent across the internal carotid artery (ICA) lesion into the common carotid artery (CCA) thereby covering the ECA. CEA was performed with eversion endarterectomy of the ECA.

RESULTS

The mean peak systolic velocities (PSV) in the ICA pre-CAS and pre-CEA were 361 and 352 cm/s, respectively. In terms of CAS, there was a significant increase in ECA velocities versus baseline at 12 (p = 0.009), 18 (p = 0.00001), and 24 (p = 0.005) months. In the CEA group, there was a significant decrease in ECA velocities versus baseline at 1 (p = 0.01) and 6 (p = 0.004) months. There were 2 occluded ECAs in follow-up in the CAS group and none in the CEA group. No significant differences were noted when comparing preprocedural ICA or ECA velocities. However, at the 1-, 6-, and 12-month intervals, the ECA velocities in the CAS group were significantly higher than in the CEA group (p = 0.03, p = 0.001, and p = 0.0004, respectively). There were no neurological symptoms in any patients during the study period.

CONCLUSION

Although progressive stenosis of the ECA is noted during CAS, the ECA usually does not occlude. Furthermore, there are no associated neurological symptoms. Thus, apprehension for progressive ECA occlusion should not be a contraindication to CAS. In addition, concern for ECA coverage should not deter stent extension from the ICA to the CCA during CAS.

A clinical survey of vascular stents

As a result of the many different potential locations to be treated, it is still difficult to evaluate the indications for efficacy and safety of non-coronary percutaneous transluminal angioplasty (PTA) and stenting versus surgical methods, such as endarterectomy or bypass grafts. This paper reviews pertinent data published in the last 5-10 years and gives an overview of the main peripheral minimally invasive vascular interventional fields.

Early Carotid Artery Stenting and Angioplasty in Patients with Acute Ischemic Stroke

OBJECTIVE:

To determine the safety of early percutaneous endovascular carotid angioplasty and stenting (CAS) after an ischemic stroke.

METHODS:

The neurointerventional database was reviewed for patients who underwent CAS after an acute ischemic stroke in two university hospitals. Clinical and radiological data were reviewed. Outcomes were worsening stroke, new stroke, or stroke-related death up to 30 days after the procedure. Procedure-related complications were also documented.

RESULTS:

A total of 38 patients with 39 procedures were identified. The mean age was 67 ± 15 years; 31 of 38 patients were Caucasian and 24 were female. Hypertension was found in 21 patients, peripheral vascular disease in 12, diabetes in 13, and coronary artery disease in 18. The median initial National Institutes of Health Stroke Scale score was 8. The carotid artery showed severe to high-grade stenosis in 28 patients, dissection was present in 6, and the rest had an acute occlusion treated with thrombolysis followed by CAS. The mean time from stroke onset to CAS was 55 ± 34 hours. The mean degree of stenosis at baseline was 86 ± 11%. In 37 procedures, complete recanalization was achieved, defined as less than 10% residual narrowing; in 2 procedures, the residual stenosis was mild (10–20%). Neurological deterioration occurred after three procedures (7.7%), with minor nondisabling stroke in two and death from intracranial hemorrhage in one.

CONCLUSION:

If deemed necessary and in certain circumstances, early CAS seems to be safe after acute ischemic stroke if infarction volume is small and neurological deficit is mild.

Angioplasty and stenting for high-grade internal carotid artery stenosis: safety study in 39 selected patients

BACKGROUND

Carotid angioplasty and stenting (CAS) is sometimes used as an alternative to surgery, despite the lack of evidence for its safety and efficacy.

METHOD

Over a 33-month period, 39 consecutive patients with a stenosis >/=70% underwent CAS (4 in a randomized trial and 35 because of contra-indications for surgery).

RESULTS

In 5 patients (13%; 95% CI: 3-23), a major complication occurred (3 disabling ischaemic strokes, 1 myocardial infarction, 1 acute interstitial nephropathy). In 7 patients (18%; 95% CI: 6-30), a minor complication occurred (5 transient ischaemic attacks, 1 transient confusional state, 1 non-disabling ischaemic stroke).

CONCLUSION

CAS cannot be considered as a routine procedure and should be restricted to high-risk patients unfit for surgery.

Surgical removal of self-expanding stents from the carotid artery: does the type of stent make a difference?

PURPOSE

To evaluate the degree of difficulty in surgically removing 2 different stent models placed in the canine carotid artery.

METHODS

In 5 dogs, each carotid artery was stented with a braided Elgiloy self-expanding stent (BESES) on one side and a surface-spanning micro stent (SSMS) on the other. After 4 weeks, an arteriogram was obtained, and the stents were removed via direct surgical exposure. The minimum lengths of the skin incisions and arteriotomies, the ease of stent removal, and the presence of a distal intimal flap were recorded.

RESULTS

Stent deployment and removal were successful in each animal, but there was a substantial difference in the ease of removal. The BESES could be removed in a strand-by-strand fashion via a more proximal, smaller arteriotomy compared to the SSMS (8.8+/-1.3 versus 37.2+/-4.7 mm, p<0.01). Furthermore, a smaller skin incision (3.85+/-0.9 versus 9.75+/-0.5 cm, p<0.01) was required for the BESES. There was no distal flap formation following BESES removal, whereas SSMS removal produced a large distal flap in each artery (p<0.01).

CONCLUSIONS

Although rare, restenosis after stenting occurs, and surgical repair may become necessary in some patients. Each stent has inherent advantages and disadvantages, but the braided Elgiloy self-expanding stent lends itself to easier surgical removal, which may have important clinical implications, especially when used in the carotid artery.

Carotid redo surgery: both safe and durable

AIM

To examine the outcomes and complications of surgery for recurrent carotid stenosis.

METHODS

From 1974 to 2000, 1922 carotid endarterectomies were performed in our unit. A retrospective cohort analysis of these records identified 24 patients (1.2%) who underwent surgery for recurrent stenosis.

RESULTS

There were 13 men and 11 women in the group. Median follow up was 7.2 years (interquartile range 4.4-12.4 years). The indication for redo surgery was either symptomatic severe (80-99%) or moderate (50-79%) restenosis, or severe asymptomatic (80-99%) restenosis. Repair was performed by patch angioplasty (88%), endarterectomy alone (8%) or interposition grafting (4%). Within the 30 day perioperative period there were no deaths, no strokes (major or minor), or significant cardiac morbidity. One patient (4%) developed a permanent spinal accessory nerve deficit. Another patient (4%) required further re-intervention for recurrent disease.

CONCLUSIONS

Very low surgical morbidity and mortality was achieved in our unit by implementing a policy of selective re-intervention for carotid restenosis. Redo carotid endarterectomy can therefore be recommended as having no greater morbidity than primary carotid endarterectomy. Carotid angioplasty and stenting are not recommended as a routine alternative treatment.

Carotid Endarterectomy Using Regional Anesthesia: A Benchmark for Stenting

Regional block (RB) anesthesia for carotid surgery offers the advantage of continuously monitoring the awake patient's neurologic status during carotid cross-clamping. We retrospectively studied our experience with RB for carotid endarterectomy (CEA) procedures performed during the period January 1, 1995 through December 31, 2001. A total of 388 consecutive CEA procedures were performed; RB was used in 314 and general anesthesia (GA) in 74. Three patients required conversion from RB to GA. GA was used only in patients who could not tolerate a block or needed combined coronary artery bypass grafting (CABG) and carotid surgery. New ipsilateral stroke did not occur in RB patients; one patient extended a previous stroke. Three in-hospital deaths occurred; these were all cardiac-related. In GA patients undergoing CEA without CABG (CEA only, n = 58), one stroke and no deaths occurred. The combined stroke and mortality rate for all CEA-only patients was 1.3 per cent (five of 372). RB allows 90 per cent of procedures to be performed without shunting, thus facilitating endarterectomy and patch angioplasty. CEA performed under RB is similar to carotid stenting because both procedures allow monitoring of the awake patient's neurologic status. The very low procedural complication rate in this study warrants the consideration of carotid surgery under regional block as a benchmark for future carotid angioplasty and stenting studies.