Carotid angioplasty and stenting, success relies on appropriate patient selection

Article Outline

• Abstract
• Methods
  • Investigators
  • Patients
    • CAS
    • CEA
  • Procedures
    • CAS
    • CEA
  • Follow-up
  • Perioperative endpoints
  • Statistical analysis
• Results
  • Demographics
  • Preoperative characteristics
  • Perioperative endpoints
    • CAS
    • CEA
• Discussion
• Conclusion
• Author contributions
• References
• Copyright

Objective

Carotid angioplasty and stenting (CAS) is a percutaneous alternative to carotid endarterectomy (CEA) for treating patients with carotid artery stenosis. This study sought to evaluate whether patients at increased perioperative risk for CEA may be treated with CAS while maintaining equivalent outcomes.

Methods

This study was a nonblinded, retrospective analysis of data obtained from September 2002 to present in the CAS group and from January 1997 to present in the CEA group. Two hundred thirty-one CAS and 647 CEA procedures were performed. Patients were selected for CAS based on criteria that placed them at increased risk for standard CEA surgery. Except for percentage women treated, baseline demographics did not differ between patients treated with CAS and CEA: mean age (72.0 years [range 46-94] vs 70.5 years [range 42-92], P = NS), mean follow-up (12.8 ± 11.8 months vs 8.7 ± 10.0 months, P = NS) and percentage women treated (41.4% vs 32.3%, P = .03). Cerebral protection devices were used in 228/231 patients treated with CAS, and each patient underwent an NIH Stroke Scale assessment 24 hours postoperatively and at 30 days follow-up by an independent observer.

Results

Preoperative neurologic symptoms did not differ between patients treated with CAS and CEA: amaurosis fugax (6.06% vs 6.96%, P = NS), transient ischemic attacks (13.4% vs 13.9%, P = NS), strokes (19.9% vs 14.1%, P = NS) and total symptoms (27.7% vs 30.5%, P = NS). Due to the selection of patient groups based on predefined clinical characteristics, factors associated with an increased risk of complications from standard CEA surgery were generally more prevalent in patients treated with CAS: neck irradiation (6.06% vs 1.24%, P < .001), neck dissection for cancer therapy (7.8% vs 1.5%, P < .001), prior ipsilateral CEA (15.2% vs 3.4%, P ≤ .001), contralateral carotid artery occlusion (12.1% vs 1.1%, P < .001), modified Goldman Cardiac Risk II-moderate risk (26.0% vs 11.3%, P < .001) and modified Goldman Cardiac Risk III-high risk (16.4% vs 2.1%, P < .001) in patients treated with CAS and CEA, respectively. Perioperative outcomes did not differ between patients treated with CAS and CEA: myocardial infarction (MI) (1.7% vs 2.6%, P = NS), stroke without residual symptoms (1.3% vs 1.2%, P = NS), stroke with residual symptoms (0.4% vs 0.8%, P = NS), mortality (0.4% vs 0.6%, P = NS), and total MI/stroke/mortality rate (3.9% vs 5.3%, P = NS).

Conclusions

The data in this study demonstrate that high-risk patients undergoing CAS had comparable outcomes to low-risk patients undergoing CEA. This study supports the use of CAS as a reasonable alternative for patients at increased perioperative risk for CEA.

The treatment of extracranial carotid artery occlusive disease is intended to decrease the risk of stroke. Prospective randomized controlled trials have provided level I evidence to support the use of carotid endarterectomy (CEA) as standard therapy for achieving durable freedom from stroke in symptomatic and asymptomatic patients.¹, ², ³, ⁴, ⁵ However, these trials excluded patients that exhibited risk factors associated with increased complication rates for patients undergoing CEA. These risk factors included clinically significant cardiopulmonary disease, contralateral carotid artery occlusion, recurrent carotid artery stenosis, previous neck external radiation therapy (XRT), previous neck surgery, and age greater than 80 years old. In response to the lack of data in patients exhibiting these risk factors, observational reports were conducted that preliminarily demonstrated the safety of CEA in these high-risk patient cohorts.⁶, ⁷, ⁸, ⁹, ¹⁰, ¹¹, ¹², ¹³, ¹⁴, ¹⁵ Nevertheless, multi-institutional and Medicare analyses have demonstrated increased complication rates in these high-risk patients when they are treated with CEA.¹⁶, ¹⁷, ¹⁸

Carotid angioplasty and stenting (CAS) is a percutaneous procedure for treating patients with carotid stenosis, and it has emerged as a potential alternative therapy for patients that are at increased risk for CEA.¹⁹, ²⁰ Advantages include the avoidance of general anesthesia, lack of a neck incision, and lessening risk for cranial nerve injury and wound complications.²¹

For patients treated with CAS, increased procedural risk appears to result from patient age greater than 80 years old, adverse lesion characteristics including stenosis of greater than 85%, calcification throughout the lesion, and increased lesion length, and adverse access vessel characteristics including aortic arch calcification, innominate or common carotid artery stenosis, and common carotid and internal carotid artery tortuosity.²², ²³, ²⁴ This study sought to evaluate whether patients at increased perioperative risk for CEA may be treated with CAS while maintaining equivalent outcomes.

Back to Article Outline

Methods 

Data for this study were derived from a joint institution, prospectively maintained database from November 2002 to present in the CAS group and from January 1997 to present in the CEA group. This study was a nonblinded, retrospective analysis, and patients were selected for CAS based on criteria that placed them at increased risk for standard CEA surgery. The internal review board and ethics committee approved the study protocol.

Investigators 

Data from all vascular surgeons at the participating institutions were included. All of the surgeons had performed greater than 25 CEAs; and of the investigators performing CAS, all had performed greater than 25 interventions with at least one half as primary operator.

Patients 

Two hundred thirty-one CAS procedures were performed on 215 patients. Patients were selected preferentially for CAS based on a history of neck XRT, neck dissection for cancer therapy, recurrent carotid artery stenosis, contralateral carotid artery occlusion, and a history of severe cardiopulmonary disease as evidenced by elevated modified Goldman Cardiac Risk Scores (Table I, Table II). Percentage stenosis was determined by North American Symptomatic Carotid Endarterectomy Trial (NASCET) angiographic criteria;¹ 59% of CAS procedures were performed either as part of a clinical trial or a postmarket registry.

Table I. Preoperative characteristics

Characteristic	CAS N = 231	CEA N = 647	P value
	Percentage
Preoperative symptoms
Urgent operations	6.6	3.6	.11
Total symptoms	27.7	30.5	.06
Amaurosis fugax	6.1	7.0	.75
Transient ischemic attack	13.4	13.9	.94
Stroke	19.9	14.1	.09
Preoperative cardiac history
NYHA Angina III	34.8	7.0	<.001
NYHA Angina IV	3.4	0.7	.02
Edema	20.9	5.2	<.001
Aortic stenosis	5.4	0.5	<.001
Arrhythmia	49.0	8.7	<.001
Premature ventricular contractions	26.5	0.5	<.001
CABG	23.4	9.6	<.001
Preoperative noncardiac history
Hypertension	87.6	76.5	<.001
Hyperlipidemia	67.1	53.2	<.001
Peripheral vascular disease	22.5	31.0	.02
Neck XRT	6.1	1.2	<.001
Neck dissection for cancer	7.8	1.5	<.001
Recurrent stenosis	15.2	3.4	<.001
Contralateral occlusion	12.1	1.1	<.001

CABG, Coronary artery bypass graft; CAS, carotid angioplasty and stenting; CEA, carotid endarterectomy; COPD, chronic obstructive pulmonary disease; NYHA Angina III, New York Heart Association Angina Class III: Marked limitation of ordinary physical activity. Walking one to two blocks on the level and climbing more than one flight in normal conditions; NYHA Angina IV, New York Heart Association Class IV: Inability to carry on any physical activity without discomfort - anginal syndrome may be present at rest; neck XRT, neck external radiation treatment.

Table II. Modified Goldman Cardiac Risk Score

CAS, Carotid angioplasty and stenting; CEA, carotid endarterectomy.

Six hundred forty-seven CEA surgeries were performed on 575 patients. Patients selected for CEA preferentially lacked a history of neck XRT, neck dissection for cancer therapy, recurrent carotid artery stenosis, contralateral carotid artery occlusion, and had lower modified Goldman Cardiac Risk Scores (Table I, Table II). In addition, during the initial angiographic evaluation of the CAS procedure, anatomic and lesion criteria were evaluated to determine if the patient was at high risk for undergoing CAS. Two patients were selected for CEA and one patient for transcervical CAS due to unfavorable anatomic characteristics, including bovine arch anatomy and excessive internal carotid artery (ICA) tortuosity. Preoperative percentage carotid artery stenosis was measured routinely by duplex ultrasonography, magnetic resonance angiography (MRA) or both. In rare and equivocal cases amounting to 3.4% of patients treated with CEA, percentage stenosis was measured by conventional angiography using NASCET criteria.

Procedures 

Endovascular procedures were performed by vascular surgeons in an operating room angiography suite equipped with a fixed imaging system (Siemens AG, Munich, Germany). Local anesthetic without sedation and femoral access were used in all cases. A self-expanding stent was deployed in each CAS procedure, and emboli-protection devices were employed in all but three cases (Table III). Perioperative anticoagulation for patients treated with CAS is described in Table IV.

Table III. Self expanding stents and emboli protection devices

Table IV. Carotid angioplasty and stenting anticoagulation protocol

CAS, Carotid angioplasty and stenting.

Vascular surgeons performed the surgeries using standard technique.²⁵ Anesthetic and intraoperative parameters were as follows: general anesthesia 95.8%, cervical block 4.2%, shunt 19.7%, electroencephalogram 75%, and carotid artery patching 99.1%. Perioperative anticoagulation for patients undergoing CEA consisted of intraoperative heparinization with goal ACT of 250-350 and aspirin 81 mg daily.

Follow-up 

Each patient underwent an independent National Institutes of Health Stroke Scale (NIHSS) assessment postoperatively by a neurologist or a NIHSS certified provider. A neurologist confirmed each documented stroke. Postoperative follow-up visits were scheduled for 1, 3, 6, 9, and 12 months, as well as annually thereafter. Carotid duplex studies were performed at each follow-up visit. Follow-up time averaged 12.8 ± 11.8 months in patients treated with CAS and 8.7 ± 10.0 months in patients treated with CEA, P = NS.

Perioperative endpoints 

Primary endpoints included stroke, which was divided into deficits resolving within 72 hours and deficits with residual symptoms persisting beyond 72 hours; myocardial infarction (MI), which was diagnosed by cardiac enzyme elevation and electrocardiogram; mortality and the total combined MI, stroke and mortality rate. Secondary endpoints included cranial nerve injury, neck hematoma, wound infection, groin hematoma, groin pseudoaneurysm, and late restenosis. With the exception of late restenosis, primary and secondary endpoints were only included if they occurred within 30 days of the procedure.

Statistical analysis 

χ² with Yates' correction was performed for all discrete variables, and unpaired t tests were used for all normally distributed continuous variables using SPSS ver. 15.0 for Windows (Microsoft, Chicago, Ill). All values are represented as a mean ± standard deviation where applicable. P < .05 is considered statistically significant.

Back to Article Outline

Results 

Demographics 

A significant difference in mean age was not observed between patients treated with CAS and CEA (72.1 ± 9.9 years [range 46-94] vs 70.5 ± 9.1 years [range 42-92], P = NS). The percentage of women treated with CAS was greater than the percentage of women treated with CEA (41.4% vs 32.3%, P = .03). The percentage of right-sided procedures did not differ between patients treated with CAS and CEA (49.8% vs 46.2%, P = NS).

Preoperative characteristics 

Due to the selection of patient groups based on predefined clinical characteristics, factors associated with an increased risk of complications from standard CEA surgery were generally more prevalent in patients treated with CAS. Significant differences in preoperative symptomatology were not present between patients treated with CAS and CEA: amaurosis fugax (6.1% vs 7.0%, P = NS), transient ischemic attacks (13.4% vs 13.9%, P = NS), preoperative strokes (19.9% vs 14.1%, P = NS) and total neurological symptoms (27.7% vs 30.5%, P = NS). Additionally, a significant difference was not noted for patients who underwent urgent CAS or CEA for crescendo symptoms (CAS 6.6% vs CEA 3.6%, P = NS) (Table I).

The following represent risk factors for surgery that were more prevalent in patients treated with CAS compared with CEA: hypertension (87.6% vs 76.5%, P < .001), hyperlipidemia (67.1% vs 53.2%, P < .001), neck XRT (6.1% vs 1.2%, P < .001), neck dissection for cancer therapy (7.8% vs 1.5%, P < .001), and prior ipsilateral CEA (15.2% vs 3.4%, P < .001). A history of peripheral vascular disease (PVD), however, was more prevalent in patients treated with CEA (CAS 22.5% vs CEA 31.0%, P = .02) (Table I).

With respect to preoperative lesion characteristics, patients treated with CAS presented more frequently with a contralateral occlusion (12.1% vs 1.1%, P < .001), and patients treated with CEA presented more frequently with bilateral carotid artery stenosis greater than 50% (31.3% vs 59.7%, P < .001). Preoperative percentage stenosis did not differ between patients treated with CAS and CEA (88.1 ± 11.2 vs 79.3 ± 15.2, P = NS). Specific to those patients treated with CAS, 17.7% had bovine variant aortic arch anatomy.

Preoperative cardiac history revealed the greatest disparity between patients treated with CAS and CEA: NYHA class III angina (34.8% vs 7.0%, P < .001), NYHA class IV angina (3.4% vs 0.7%, P = .02), history of edema (20.9% vs 5.2%, P < .001), aortic stenosis (5.4% vs 0.5%, P < .001), history of any arrhythmia (49.0% vs 8.7%, P < .001), history of premature ventricular contractions (PVCs) (26.5% vs 0.5%, P <.001), and history of coronary artery bypass grafting (CABG) (23.4% vs 9.6%, P < .001) (Table I). This reflected directly in the composite modified Goldman Cardiac Risk Scores, which predict the risk for perioperative complications from surgery (ie, cardiac death, intraoperative or postoperative MI, pulmonary edema and nonfatal ventricular tachycardia) (Table II).²⁶ Patients treated with CAS were more frequently in the moderate and high-risk categories compared to patients treated with CEA: Goldman II-moderate risk (26.0% vs 11.3%, P < .001) and Goldman III-high risk (16.4% vs 2.1%, P < .001).

Perioperative endpoints 

Successful completion of CAS occurred in 98.7% of cases. Three patients failed to undergo CAS due to unfavorable anatomic characteristics, including bovine arch anatomy and excessive ICA tortuosity. Two of the patients subsequently underwent CEA, and one patient underwent transcervical CAS. Vascular access site complications for patients treated with CAS included seven (3.0%) groin hematomas that resolved spontaneously and two (0.9%) common femoral artery pseudoaneurysms that were treated with thrombin injection. Late restenosis of the treated carotid artery requiring reintervention occurred in one (0.4%) patient.

Surgical site complications in patients treated with CEA included one (0.2%) wound infection that resolved with superficial drainage of the cervical incision, four (0.6%) cranial nerve palsies that resolved within 6 months of surgery, and ten (1.5%) neck hematomas, two (0.3%) of which required operative evacuation. Late restenosis requiring reintervention occurred in 10 (1.5%) patients.

Statistically significant differences were not observed in the primary endpoints between patients treated with CAS and CEA: MI (1.7% vs 2.6%, P =NS), total stroke (1.7% vs 2.0%, P = NS), stroke without residual symptoms after 72 hours (1.3% vs 1.2%, P = NS), stroke with residual symptoms after 72 hours (0.4% vs 0.8%, P = NS), mortality (0.4% vs 0.6%, P = NS) and total MI/stroke/morality (3.9% vs 5.3%, P = NS) (Table V).

Table V. Primary endpoints

Perioperative events	CAS N = 231	CEA N = 647	P value
	Percentage
Total MI	1.7	2.6	.26
Total stroke	1.7	2.0	.79
No residual symptoms	1.3	1.2	.94
Residual symptoms	0.4	0.8	.94
Mortality	0.4	0.6	.74
Total MI/stroke/mortality	3.9	5.3	.37

CAS, Carotid angioplasty and stenting; CEA, carotid endarterectomy; MI, myocardial infarction.

Back to Article Outline

Discussion 

Randomized controlled trials have established CEA as the standard therapy for extracranial carotid artery occlusive disease in conventional-risk patients.¹, ², ³, ⁴, ⁵ The original trials excluded patients with anatomic and physiologic factors that were associated with increased complication rates from surgery. Patients with the following anatomic factors were preferentially excluded from the cited trials: contralateral carotid artery occlusion, recurrent stenosis, neck XRT, neck dissection, and lesions distal to C2. Similarly, patients with the following physiologic factors were preferentially excluded: age greater than 80 years old and severe cardiopulmonary disease as measured by the modified Goldman Cardiac Risk Score.

CAS has emerged as a percutaneous alternative to treat extracranial carotid artery stenosis in patients at increased risk for standard CEA surgery. Advantages to CAS include the avoidance of general anesthesia, the elimination of a neck incision and a potential reduction in periprocedural hemodynamic fluctuation. Disadvantages to CAS include the risk of stroke, sparse data on long-term durability, and access site complications.²¹

Patients with factors determined to increase the perioperative risk of standard CEA surgery such as prior neck XRT, re-operation, and an elevated modified Goldman Cardiac Risk Score can be treated successfully with CAS while achieving complication rates equivalent to CEA. Such factors may have a more limited role in influencing periprocedural risk in patients treated with CAS. This was partially demonstrated in the Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy (SAPPHIRE) trial, which compared CAS with cerebral protection to endarterectomy in patients with moderate-to-severe stenosis and associated cardiopulmonary comorbidities. The SAPPHIRE trial demonstrated improved periprocedural outcomes for patients treated using CAS with cerebral protection compared with standard CEA surgery in high surgical risk patients with respect to the outcomes of MI, stroke and mortality.²⁰

Successful use of CAS is predicated on avoiding specific procedural risk factors including age greater than 80 years old, aortic arch calcification, aortic arch elongation or distortion, innominate or common carotid artery stenosis, and common carotid or internal carotid artery tortuosity. In patients treated with CAS, the incidence of high-risk anatomy and of combined MI, stroke and death are increased in octogenarians compared with patients less than 80 years old.²², ²³, ²⁴ The presence of unfavorable anatomic and lesion characteristics may contribute to poor outcomes with CAS, likely due to the increased technical difficulty of the procedure. For example, tortuosity and stenosis of access vessels may complicate sheath positioning, and the increased catheter manipulation and repeated endothelial injury may increase the risk for stroke. Tortuosity of the internal carotid artery may increase the difficulty of positioning the emboli protection device, preventing complete vessel wall apposition and decreasing the efficacy of the device at capturing embolic particles. Lesions evaluated by B-mode ultrasound and determined to have echolucent plaque with a gray-scale median score of less than 25 have been reported to be more friable and prone to dislodgement of emboli.²⁷ Increased lesion length has also been associated with an increased risk for stroke in patients treated with CAS.²⁸, ²⁹

The current study compared patients treated with CAS to patients treated with standard CEA surgery. Patients considered to be at increased risk for CEA based on a history of neck XRT, neck dissection for cancer therapy, recurrent carotid artery stenosis, contralateral carotid artery occlusion, and who had severe cardiopulmonary disease as evidenced by elevated modified Goldman Cardiac Risk Scores, were preferentially treated with CAS. Age greater than 80 years old was not used as a selection criterion that prohibited treatment with CAS. However, during the CAS procedure anatomic and lesion criteria were evaluated to determine the potential to increase the risk of the procedure. Utilizing this strategy there was a 98.7% procedural success rate for CAS, with two patients subsequently undergoing CEA and one patient subsequently undergoing transcervical CAS. Overall, surgical site, vascular access site, and perioperative morbidity and mortality occurred with low frequencies and did not differ significantly between patients treated with CAS and CEA. Bleeding complications occurred with similar frequencies in patients treated with CAS or CEA. No cranial nerve injuries were reported in patients treated with CAS, therefore they occurred with significantly greater frequency in patients treated with CEA, despite the low frequency of 0.6%. Additionally, patients treated with CAS or CEA did not exhibit significant differences in the primary endpoints of MI, stroke, mortality, and total combined MI, stroke, and mortality rates.

This study has the limitation that it was a retrospective analysis. As a result, the patients were not prospectively randomized to treatment groups, and they were subject to selection bias. In particular, patients treated with CAS were selected based on predefined clinical criteria that placed them at increased risk for CEA. Nevertheless, PVD was still more prevalent in patients treated with CEA. In patients treated with CEA, the short average follow-up was discordant with the duration of the study and therefore should be enhanced. Additionally, the study period for patients treated with CEA was longer compared with patients treated with CAS, generating a larger patient cohort and potentially confounding the data. Over the course of the study the treatment of CEA remained relatively constant in terms of technique and anesthesia, and the surgeons remained the same. Therefore, the authors believe that additional value was gained by the inclusion of “earlier patients” in the CEA patient cohort. In patients treated with CAS, the variation in stents and cerebral protection devices used introduced additional bias and diminished the power of the statistical analysis.

To conclude, the low incidence of events in the current study and the previously demonstrated utility of CAS and CEA lend support to the strategy of treating patients at increased risk for standard CEA surgery with CAS. Ultimately, long-term freedom from stroke and stroke-related death is the true gauge of success, and further study is still needed.

Back to Article Outline

Conclusion 

The data in this study demonstrate that high-risk patients treated with CAS achieve comparable outcomes to low-risk patients treated with CEA. Examples of perioperative factors that increase the risk for standard CEA surgery include contralateral carotid artery occlusion, recurrent stenosis, neck XRT, neck surgery, and an elevated modified Goldman Cardiac Risk Score. Similarly, successful use of CAS is predicated on avoiding perioperative complications, particularly stroke. Procedural risk factors specific to CAS including age greater than 80 years old, aortic arch calcification, access vessel tortuosity, and stenosis as well as ICA tortuosity may increase the technical difficulty of CAS and therefore may increase periprocedural risk. Limiting the impact of unfavorable anatomic features appears to be important to the successful use of CAS. This study supports the use of CAS as a reasonable alternative for patients at increased perioperative risk for CEA.

Back to Article Outline

Author contributions 

Back to Article Outline

References 

1. Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis (North American Symptomatic Carotid Endarterectomy Trial Collaborators). N Engl J Med. 1991;325:445–453
   • View In Article
   • MEDLINE
   • CrossRef
2. MRC European Carotid Surgery Trial: interim results for symptomatic patients with severe (70%-99%) or with mild (0%-29%) carotid stenosis (European Carotid Surgery Trialists' Collaborative Group). Lancet. 1991;337:1235–1243
   • View In Article
   • Abstract
   • CrossRef
3. Endarterectomy for asymptomatic carotid artery stenosis (Executive Committee for the Asymptomatic Carotid Atherosclerosis Study). JAMA. 1995;273:1421–1428
   • View In Article
   • MEDLINE
4. Hobson RW, Weiss DG, Fields WS, Goldstone J, Moore WS, Towne JB, et al. Efficacy of carotid endarterectomy for asymptomatic carotid stenosis (The Veterans Affairs Cooperative Study Group). N Engl J Med. 1993;328:221–227
   • View In Article
   • MEDLINE
   • CrossRef
5. Mayberg MR, Wilson SE, Yatsu F, Weiss DG, Messina L, Hershey LA, et al. Carotid endarterectomy and prevention of cerebral ischemia in symptomatic carotid stenosis (Veterans Affairs Cooperative Studies Program 309 Trialist Group). JAMA. 1991;266:3289–3294
   • View In Article
   • MEDLINE
6. Ballotta E, Da Giau G, Saladini M, Abbruzzese E. Carotid endarterectomy in symptomatic and asymptomatic patients aged 75 years or more: perioperative mortality and stroke risk rates. Ann Vasc Surg. 1999;13:158–163
   • View In Article
   • Abstract
   • Full-Text PDF (492 KB)
   • CrossRef
7. Maxwell JG, Taylor AJ, Maxwell BG, Brinker CC, Covington DL, Tinsley E. Carotid endarterectomy in the community hospital in patients age 80 and older. Ann Surg. 2000;231:781–788
   • View In Article
   • MEDLINE
   • CrossRef
8. Mozes G, Sullivan TM, Torres-Russotto DR, Bower TC, Hoskin TL, Sampaio SM, et al. Carotid endarterectomy in SAPPHIRE-eligible high-risk patients: implications for selecting patients for carotid angioplasty and stenting. J Vasc Surg. 2004;39:958–965discussion 965-6
   • View In Article
   • Abstract
   • Full Text
   • Full-Text PDF (103 KB)
   • CrossRef
9. O'Hara PJ, Hertzer NR, Mascha EJ, Beven EG, Krajewski LP, Sullivan TM. Carotid endarterectomy in octogenarians: early results and late outcome. J Vasc Surg. 1998;27:860–869discussion 870-1
   • View In Article
   • Abstract
   • Full Text
   • Full-Text PDF (141 KB)
   • CrossRef
10. Perler BA, Dardik A, Burleyson GP, Gordon TA, Williams GM. Influence of age and hospital volume on the results of carotid endarterectomy: a statewide analysis of 9918 cases. J Vasc Surg. 1998;27:25–31discussion 31-3
    • View In Article
    • Abstract
    • Full Text
    • Full-Text PDF (83 KB)
    • CrossRef
11. Rockman CB, Jacobowitz GR, Adelman MA, Lamparello PJ, Gagne PJ, Landis R, et al. The benefits of carotid endarterectomy in the octogenarian: a challenge to the results of carotid angioplasty and stenting. Ann Vasc Surg. 2003;17:9–14
    • View In Article
    • Abstract
    • Full Text
    • Full-Text PDF (502 KB)
    • CrossRef
12. Schneider JR, Droste JS, Schindler N, Golan JF. Carotid endarterectomy in octogenarians: comparison with patient characteristics and outcomes in younger patients. J Vasc Surg. 2000;31:927–935
    • View In Article
    • Abstract
    • Full Text
    • Full-Text PDF (63 KB)
    • CrossRef
13. Thomas PC, Grigg M. Carotid artery surgery in the octogenarian. Aust N Z J Surg. 1996;66:231–234
    • View In Article
    • MEDLINE
14. Treiman RL, Wagner WH, Foran RF, Cossman DV, Levin PM, Cohen JL, et al. Carotid endarterectomy in the elderly. Ann Vasc Surg. 1992;6:321–324
    • View In Article
    • Abstract
    • Full-Text PDF (385 KB)
    • CrossRef
15. Van Damme H, Lacroix H, Desiron Q, Nevelsteen A, Limet R, Suy R. Carotid surgery in octogenarians: is it worthwhile?. Acta Chir Belg. 1996;96:71–77
    • View In Article
    • MEDLINE
16. Fisher ES, Malenka DJ, Solomon NA, Bubolz TA, Whaley FS, Wennberg JE. Risk of carotid endarterectomy in the elderly. Am J Public Health. 1989;79:1617–1620
    • View In Article
    • MEDLINE
    • CrossRef
17. Wennberg DE, Lucas FL, Birkmeyer JD, Bredenberg CE, Fisher ES. Variation in carotid endarterectomy mortality in the Medicare population: trial hospitals, volume, and patient characteristics. JAMA. 1998;279:1278–1281
    • View In Article
    • MEDLINE
    • CrossRef
18. Winslow CM, Solomon DH, Chassin MR, Kosecoff J, Merrick NJ, Brook RH. The appropriateness of carotid endarterectomy. N Engl J Med. 1988;318:721–727
    • View In Article
    • MEDLINE
    • CrossRef
19. Carotid Revascularization Using Endarterectomy or Stenting Systems (CaRESS) phase I clinical trial: 1-year results. J Vasc Surg. 2005;42:213–219
    • View In Article
    • Abstract
    • Full Text
    • Full-Text PDF (134 KB)
    • CrossRef
20. Yadav JS, Wholey MH, Kuntz RE, Fayad P, Katzen BT, Mishkel GJ, et al. Protected carotid-artery stenting versus endarterectomy in high-risk patients. N Engl J Med. 2004;351:1493–1501
    • View In Article
    • CrossRef
21. Henry M, Polydorou A, Klonaris C, Henry I, Polydorou AD, Hugel M. Carotid angioplasty and stenting under protection (State of the art). Minerva Cardioangiol. 2007;55:19–56
    • View In Article
    • MEDLINE
22. Hobson RW, Howard VJ, Roubin GS, Brott TG, Ferguson RD, Popma JJ. Carotid artery stenting is associated with increased complications in octogenarians: 30-day stroke and death rates in the CREST lead-in phase. J Vasc Surg. 2004;40:1106–1111
    • View In Article
    • Abstract
    • Full Text
    • Full-Text PDF (89 KB)
    • CrossRef
23. Lam RC, Lin SC, DeRubertis B, Hynecek R, Kent KC, Faries PL. The impact of increasing age on anatomic factors affecting carotid angioplasty and stenting. J Vasc Surg. 2007;45:875–880
    • View In Article
    • Abstract
    • Full Text
    • Full-Text PDF (692 KB)
    • CrossRef
24. Lin SC, Trocciola SM, Rhee J, Dayal R, Chaer R, Morrissey NJ. Analysis of anatomic factors and age in patients undergoing carotid angioplasty and stenting. Ann Vasc Surg. 2005;19:798–804
    • View In Article
    • Abstract
    • Full Text
    • Full-Text PDF (593 KB)
    • CrossRef
25. Dayal R, Kent KC. Carotid endarterectomy. In:  Cameron JL editors. Current surgical therapy. 8th ed.. Philadelphia, PA: Mosby; 2004;p. 45–49
    • View In Article
26. Gilbert K, Larocque BJ, Patrick LT. Prospective evaluation of cardiac risk indices for patients undergoing noncardiac surgery. Ann Intern Med. 2000;133:356–359
    • View In Article
    • MEDLINE
27. Biasi GM, Froio A, Diethrich EB, Deleo G, Galimberti S, Mingazzini P. Carotid plaque echolucency increases the risk of stroke in carotid stenting: the Imaging in Carotid Angioplasty and Risk of Stroke (ICAROS) study. Circulation. 2004;110:756–762
    • View In Article
    • CrossRef
28. Krapf H, Nagele T, Kastrup A, Bühring U, Grönewäller E, Skalej M, et al. Risk factors for periprocedural complications in carotid artery stenting without filter protection: a serial diffusion-weighted MRI study. J Neurol. 2006;253:364–371
    • View In Article
    • MEDLINE
    • CrossRef
29. Qureshi AI, Luft AR, Janardhan V, Suri MF, Sharma M, Lanzino G. Identification of patients at risk for periprocedural neurological deficits associated with carotid angioplasty and stenting. Stroke. 2000;31:376–382
    • View In Article
    • MEDLINE
    • CrossRef