Identification of patients at risk for periprocedural neurological deficits associated with carotid angioplasty and stenting

Vasoconstriction and hyperperfusion syndrome after carotid artery stenting

Background

Common complications of carotid artery stenting (CAS) are cerebral ischemia and hyperperfusion syndrome. To date, only a few cases of late-onset cerebral vasoconstriction occurring several hours after CAS have been reported. However, there are no reports of developed vasoconstriction and hyperperfusion syndrome.

Case presentation

A 79-year-old man developed vasoconstriction 1 day after carotid artery stenting. Vasoconstriction improved immediately with glucocorticoid. However, a week later, the patient developed hyperperfusion syndrome.

Conclusions

Postoperative vasoconstriction and hyperperfusion syndrome is an unrecognized complication and surgeons should be aware of it.

Periprocedural Variability of Platelet Functions in Carotid Artery Stenting: An Analysis Using VerifyNow

Objective

The assessment of platelet functions is necessary to prevent both thromboembolic and hemorrhagic complications under dual antiplatelet therapy (DAPT). Using the VerifyNow (Accumetrics, Inc., San Diego, CA, USA) assay, this study aimed to reveal time-dependent changes in platelet functions after carotid artery stenting (CAS).

Methods

We enrolled retrospectively 43 patients who underwent CAS under DAPT. Aspirin reaction unit (ARU) and P2Y12 reaction unit (PRU) values were determined on the day before and on days 1, 3, and 7 after the procedure. Multiple comparison tests (MCTs) were performed among ARU and PRU measurement points, and the proportions of hypo- and hyper-responses were compared.

Results

The median ARU values were 408 (interquartile range: 392-497) before CAS and 418 (405-470) on day 1, 405 (393.0-460.5) on day 3, and 402 (388.5-477.5) on day 7 (not significant in MCTs). The percentages of hypo-responses were 16.3%, 7.0%, 2.3%, and 7.0%, respectively (p = 0.11). The significantly different median PRU values were 173 (116.5-209.5), 233 (166.5-273.5), 139 (70.5-205.5), and 51 (9.0-79.5), respectively. The median PRU was before the procedure within the therapeutic range but exceeded the upper cutoff on day 1 and was below the lower cutoff on day 7. The percentages of hypo-responses were 14.0%, 51.2%, 18.6%, and 11.6%, respectively (p <0.001) and the percentages of hyper-responses were 9.3%, 2.3%, 23.3%, and 62.8%, respectively (p <0.001).

Conclusion

In the periprocedural CAS period, ARU values were stable, but PRU values showed time-dependent changes. PRU values were above the therapeutic range the day after CAS but decreased below this range on day 7.

Transient Cerebral Vasospasm After Carotid Artery Stenting: A Case Report and Literature Review

BACKGROUND

Cerebral embolism after carotid artery stenting (CAS) is a well-known complication, but cerebral ischemia owing to cerebral vasospasm after CAS is rare and has seldom been reported. We describe a patient with transient ischemic complications owing to reversible cerebral vasospasm of the middle cerebral artery after CAS.

CASE DESCRIPTION

A 74-year-old man presented with right hemiparesis caused by acutely scattered brain infarction in the left cerebral hemisphere. Magnetic resonance angiography showed severe stenosis of the left cervical internal carotid artery origin. CAS under a distal filter protection was performed without any intraprocedural complications, but 12 hours later, the patient had aphasia and Gerstmann syndrome. Urgent magnetic resonance imaging revealed no evidence of an intracranial hemorrhage or new cerebral infarction. However, magnetic resonance angiography showed diffuse vasospasm of the left middle cerebral artery. His symptoms and imaging findings improved gradually with conservative treatment. The patient was discharged without new neurologic deficit or recurrent attack 3 weeks after CAS.

CONCLUSIONS

In a patient with delayed neurologic symptoms after CAS, the possibility of cerebral vasospasm should be kept in mind to select appropriate treatment.

Postoperative ischemic events in patients undergoing carotid artery stenting using algorithmic selection for embolic protection

PURPOSE

Carotid artery stenting (CAS) is a valuable alternative to carotid endarterectomy, especially in high-risk patients. However, the reported incidences of perioperative stroke and death remain higher than for carotid endarterectomy, even when using embolic protection devices (EPDs) during CAS. Our purpose was to evaluate 30-day major adverse events after CAS when selecting the most appropriate EPD.

METHODS

We reviewed the clinical outcomes of 61 patients with 64 lesions who underwent CAS with EPDs. Patients who underwent CAS associated with thrombectomy and who had a preoperative modified Rankin scale score >3 were excluded from the analysis. The EPD was selected based on symptoms, carotid wall magnetic resonance imaging and lesion length, and we analyzed combined 30-day complication rates (transient ischemic attack, minor stroke, major stroke or death).

RESULTS

Forty-nine patients were men and 12 were women. The median age was 72 years (range: 59-89 years) and 44 lesions were asymptomatic. A filter-type EPD was selected in 23 procedures, distal-balloon protection in 14 procedures and proximal-occlusive protection in 27 procedures. Two patients (3.1%) experienced a transient ischemic attack and one patient (1.6%) had a minor stroke within 30 days of the procedure. No patients experienced procedure-related morbidities (modified Rankin score >2) or death.

CONCLUSIONS

The perioperative stoke rate was low when we selected a proximal-occlusive-type EPD in high-risk patients with vulnerable carotid artery disease. Our algorithm for EPD selection was an effective tool in the perioperative management of carotid artery stenosis.

Predictors of Perioperative Stroke/Death after Carotid Artery Stenting: A Review Article

Carotid artery stenting (CAS) has been recommended as an alternative treatment to carotid endarterectomy for patients with significant carotid stenosis. Only a few studies have analyzed clinical/anatomical and technical variables that affect perioperative outcomes of CAS. Following a comprehensive Medline search, it was reported that clinical factors, including age of >80 years, chronic renal failure, diabetes mellitus, symptomatic indications, and procedures performed within 2 weeks of transient ischemic attack symptoms, are associated with high perioperative stroke and death rates. They also highlighted that angiographic variables, e.g., ulcerated and calcified plaques, left carotid intervention, >90% stenosis, >10-mm target lesion length, ostial involvement, type III aortic arch, and >60°-angulated internal carotid and common carotid arteries, are predictors of increased stroke rates. Technical factors associated with increased perioperative risk of stroke include percutaneous transluminal angioplasty (PTA) without embolic protection devices, PTA before stent placement, and the use of multiple stents. This review describes the most widely quoted data in defining various predictors of perioperative stroke and death after CAS. (This is a review article based on the invited lecture of the 45th Annual Meeting of Japanese Society for Vascular Surgery.)

Transcranial Doppler Monitoring in Angioplasty and Stenting of the Carotid Bifurcation

Purpose:

To assess the impact of cerebral embolism and hemodynamic changes during the successive stages of carotid angioplasty and stenting (CAS) using transcranial Doppler (TCD) monitoring of the middle cerebral artery (MCA).

Methods:

In 297 patients (206 men; mean age 69.9±8.0 years), the association of various TCD emboli and velocity variables with procedure-related death and cerebral events (amaurosis fugax, transient ischemic attacks, and stroke) was evaluated. Baseline patient characteristics (age, sex, preoperative cerebral symptoms, and prior carotid endarterectomy) and their associations with procedure-related cerebral events were also assessed. A distinction was made between adverse events that occurred during CAS and those that happened within 7 days.

Results:

Of the 36 procedure-related retinal and cerebral events, 28 (78%) were encountered intraprocedurally; an additional 6 (2%) events occurred within 7 days after the procedure. Two (0.7%) patients died. At 1 week, the combined minor and major stroke and death rate was 3.7%. Adverse outcome was associated with >4 showers of microemboli at postdilation (odds ratio [OR] 3.2, 95% CI 1.3 to 7.8, p = 0.03), particulate macroemboli (OR 9.1, 95% CI 5.1 to 16.1, p<.001), massive air embolism from ruptured balloons (OR 11.3, 95% CI 7.6 to 16.6, p<0.001), and angioplasty-induced asystole with significant hypotension plus MCA blood flow reduction (OR 3.3, 95% CI 1.4 to 8.3, p = 0.03). Of the patient characteristics, male gender (OR 10.5, 95% CI 1.4 to 75.8, p = 0.02) and preoperative cerebral ischemia (OR 3.3, 95% CI 1.6 to 6.6, p = 0.003) were also related to outcome.

Conclusions:

In CAS, TCD monitoring provides insight into the pathogenesis of procedure-related cerebral events. Microemboli during poststent dilation, particulate macroembolism, massive air embolism, and angioplasty-induced asystole are associated with adverse outcome, as are male gender and prior cerebral ischemia.

Prognostic Factors for Neurologic Outcome in Patients with Carotid Artery Stenting

BACKGROUND

Carotid artery stenting (CAS) is a valid treatment for patients with carotid artery stenosis. The long-term outcome and prognostic factors in Asian population after CAS are not clear. This study aimed to identify the prognostic factors among Asian patients who have undergone CAS.

METHODS

We retrospectively analyzed 246 patients with CAS. Annual carotid duplex ultrasound was used to identify restenosis. Peri-procedural complications, restenosis, neurologic outcomes, and mortality were recorded. Cox regression analyses were used to identify prognostic factors.

RESULTS

The mean follow-up time was 49.2 months. Procedural success was achieved in 237 patients (98.3%), and protection devices were used in 208 patients (84.5%). Within 30 days of CAS, 13 (4.3% per procedure) peri-procedural complications occurred. During the follow-up period, 24 (9.7%) patients developed restenosis, and 37 (15.0%) developed ischemic strokes. In a multiple logistic regression analysis, head and neck radiotherapy [hazard ratio (HR) = 9.9, 95% confidence interval (CI), 3.38-29.1, p < .001], stent diameter (HR = 0.72, 95% CI, 0.58-0.89, p = .003), and predilatation (HR = 3.08 95% CI, 1.21-7.81, p = .018) were independent predictors for restenosis. In Cox regression analysis, hypercholesterolemia (HR = 0.25, 95% CI, 0.07-0.94, p = .04), head and neck radiotherapy (HR = 6.2, 95% CI, 1.8-21.3, p = .004), and restenosis (HR = 3.6, 95% CI, 1.1-11.18, p = .04) were predictors for recurrent ipsilateral ischemic stroke.

CONCLUSIONS

CAS provides reliable long-term results in Asian patients with carotid stenosis. Restenosis is associated with an increased rate of recurrent stroke and should be monitored carefully following CAS.

KEY WORDS

Carotid artery disease • Prognosis • Cerebrovascular disease.

Clinical Presentation, Imaging, and Management of Complications due to Neurointerventional Procedures

Neurointervention is a rapidly evolving and complex field practiced by clinicians with backgrounds ranging from neurosurgery to radiology, neurology, cardiology, and vascular surgery. New devices, techniques, and clinical applications create exciting opportunities for impacting patient care, but also carry the potential for new iatrogenic injuries. Every step of every neurointerventional procedure carries risk, and a thorough appreciation of potential complications is fundamental to maximizing safety. This article presents the most frequent and dangerous iatrogenic injuries, their presentation, identification, prevention, and management.

Incidence and timing of hypotension after transcervical carotid artery stenting: correlation with postoperative complications

OBJECTIVES

To assess the incidence and timing of hypotension after carotid artery stenting (CAS) and its correlation with postoperative complications.

BACKGROUND

CAS-associated postoperative hypotension has been linked to surgical morbidity and mortality, especially to stroke and cardiac complications.

METHODS

Ninety-seven consecutive patients undergoing transcervical CAS were monitored for at least 12 hr after operation. Hypotension was defined as systolic blood pressure < 90 mm Hg. Patients were divided into three groups: normal blood pressure and early (≤6 hr) and late (>6 hr) hypotension. Complications were recorded.

RESULTS

Hypotension occurred in 34% of the patients (early hypotension in 63% of them). Hypotension was recorded in 21.6% of patients during surgery and in 21.6%, 15.5%, and 1.0% at 6, 12, and 24 hr postoperatively. Bradycardia occurred in 26.8% during operation and in 25.8%, 13.4%, and 10.3% at 6, 12, and 24 hr after surgery. Intraoperative bradycardia (P = 0.01) and hypotension (P = 0.02) were predictors of postoperative hypotension. The overall rate of complications was 5% without differences between the study groups. The mean length of stay was 3, 3.6, and 2.8 days in the normotensive, early hypotension, and late hypotension groups, respectively.

CONCLUSIONS

Most postoperative hypotension episodes occurred within the first 6 hr, and more than one-third between the 6 and 12 hr post-procedure. All patients with late hypotension were asymptomatic. There was no difference in complications between the study groups. In patients undergoing ambulatory CAS, hemodynamic monitoring in the postoperative period is particularly important during the first 12 hr.

MRI lesions after invasive therapy of carotid artery stenosis: a risk-modeling analysis

BACKGROUND

Diffusion-weighted imaging (DWI) abnormalities can frequently be detected after carotid endarterectomy (CEA) and carotid angioplasty with stent placement (CAS) of the carotid arteries. We looked for possible predictors for the development of DWI lesions during the intervention.

METHODS

We investigated 41 patients who underwent CAS without protection devices and 93 patients who underwent CEA. DWI studies were performed 1 day before and after the intervention.

RESULTS

Ischemic complications consisted of two strokes (2.2%) in the CEA group and one stroke (2.4%) in the CAS group. DWI lesions were detected in 28.0% of all patients after intervention. Using a multivariate regression analysis, diabetes mellitus (DM), hyperlipidemia, symptomatic stenosis, age and CAS were found to be significant predictors for the occurrence of DWI lesions.

CONCLUSIONS

DWI is an objective and highly sensitive method for monitoring interventions of the carotid arteries. Our results point to an increased risk of patients with diabetes and hyperlipidemia to develop DWI lesions during invasive therapy of the ICA.

Assessing the impact of distal protection filter design characteristics on 30-day outcomes of carotid artery stenting procedures

OBJECTIVE

This study aims to review retrospectively the records of patients treated with carotid artery stenting (CAS) to investigate the potential correlations between clinical variables, distal protection filter (DPF) type and characteristics, and 30-day peri-/postprocedural outcomes.

METHODS

This is a multicenter, single-arm, nonrandomized retrospective study of patients who underwent filter-protected CAS in the Pittsburgh, Pennsylvania, region between July 2000 and May 2011. Analysis of peri-/postprocedural complications included myocardial infarction, transient ischemic attacks (TIA), stroke, death, and a composition of all adverse events (AEs). Filter characteristics for Accunet (Abbott Vascular, Santa Clara, Calif; n = 429 [58.8%]), Angioguard (Cordis Endovascular, Miami Lakes, Fla; n = 114 [15.6%]), FilterWire (Boston Scientific, Natick, Mass; n = 113 [15.5%]), Spider (ev3 Endovascular, Plymouth, Minn; n = 45 [6.2%]), and Emboshield (Abbott Vascular; n = 24 [3.3%]) were previously determined in vitro and were used to find correlations with CAS procedural outcomes. Both univariate and multivariate analyses were performed, as well as goodness-of-fit tests to find multivariate correlations with procedural outcomes.

RESULTS

In total, 731 CAS procedures using six different DPFs were analyzed. Peri-/postprocedural AEs included 19 TIAs (2.6%), 38 strokes (5.2%), one myocardial infarction (0.1%), 19 deaths (3.6%), and a total of 61 patients with complications (8.3%). Univariate analysis for filter design characteristics showed that the composite of AE was negatively associated with both vascular resistance (P = .01) and eccentricity (P = .02) and was positively associated with porosity (P = .0007), number of pores (P = .005), and pore density (P = .001). Multivariate analysis and the goodness-of-fit test revealed that patients with a history of congestive heart failure, stroke, and TIA (each with odds ratio >1) led to a good-fit model P value of .72 for peri-/postprocedural AEs. Multivariate analysis was inconclusive for all filter design characteristics.

CONCLUSIONS

The following filter design characteristics are independently significant for minimizing peri-/postprocedural AEs: higher vascular resistance, concentric in shape, greater capture efficiency, lower porosity, lower number of pores, and lower pore density. Lower porosity and smaller wall apposition were also found to be independently significant for minimization of peri-/postprocedural TIAs. This information can be used when considering the desirable design characteristics of future DPFs.).

Predictors and Timing of Neurological Complications Following Intracranial Angioplasty and/or Stent Placement

BACKGROUND:

Transient or permanent neurological complications can occur in the periprocedural period following intracranial angioplasty and/or stent placement. Which patients are at risk and the time period for maximum vulnerability among those who undergo intracranial angioplasty and/or stent placement have not been formally studied.

OBJECTIVE:

To assess the predictors and timing of neurological complications following intracranial angioplasty and/or stent placement in the periprocedural period in a consecutive series of patients.

METHODS:

We reviewed medical records and angiograms of consecutive patients treated with intracranial angioplasty and/or stent placement in 3 academic institutions. We evaluated the effect of demographic, clinical, intraprocedural, and angiographic risk factors on subsequent development of periprocedural neurological complications. Periprocedural neurological complications were defined as new or worsening transient or permanent neurological complications that occurred during or within 1 month of the procedure. We also recorded the timing and nature of neurological complications in the periprocedural period.

RESULTS:

A total of 92 patients were included in the study (mean age ± standard deviation: 59 ± 14 years; 59 were men). The overall rate of in-hospital neurological complications was 9.8% (9 of 92 patients). Eight out of 9 neurological complications occurred either during the procedure or within 6 hours thereafter. Presence of diabetes mellitus (P = .003) and use of balloon-expandable stent (P = .09) were associated with periprocedural neurological complications. The degree of pre- and post-procedure stenosis, morphological appearance, and length of lesion were unrelated to periprocedural complications.

CONCLUSION:

Patients with diabetes mellitus and those treated with balloon expandable stents are at high risk for periprocedural neurological complications. The first 6 hours following intracranial angioplasty and stent placement represent the period of highest risk.

MRI plaque imaging reveals high-risk carotid plaques especially in diabetic patients irrespective of the degree of stenosis

Background

Plaque imaging based on magnetic resonance imaging (MRI) represents a new modality for risk assessment in atherosclerosis. It allows classification of carotid plaques in high-risk and low-risk lesion types (I-VIII). Type 2 diabetes mellitus (DM 2) represents a known risk factor for atherosclerosis, but its specific influence on plaque vulnerability is not fully understood. This study investigates whether MRI-plaque imaging can reveal differences in carotid plaque features of diabetic patients compared to nondiabetics.

Methods

191 patients with moderate to high-grade carotid artery stenosis were enrolled after written informed consent was obtained. Each patient underwent MRI-plaque imaging using a 1.5-T scanner with phased-array carotid coils. The carotid plaques were classified as lesion types I-VIII according to the MRI-modified AHA criteria. For 36 patients histology data was available.

Results

Eleven patients were excluded because of insufficient MR-image quality. DM 2 was diagnosed in 51 patients (28.3%). Concordance between histology and MRI-classification was 91.7% (33/36) and showed a Cohen's kappa value of 0.81 with a 95% CI of 0.98-1.15. MRI-defined high-risk lesion types were overrepresented in diabetic patients (n = 29; 56.8%). Multiple logistic regression analysis revealed association between DM 2 and MRI-defined high-risk lesion types (OR 2.59; 95% CI [1.15-5.81]), independent of the degree of stenosis.

Conclusion

DM 2 seems to represent a predictor for the development of vulnerable carotid plaques irrespective of the degree of stenosis and other risk factors. MRI-plaque imaging represents a new tool for risk stratification of diabetic patients.

See Commentary: http://www.biomedcentral.com/1741-7015/8/78/abstract

[Anesthesia in interventional neuroradiology]

Interventional neuroradiology procedures have become increasingly complex, requiring planning and coordination. Key roles are played by the anesthesiologist and the radiologist, as well as by technicians and nurses. This review aims to analyze the anesthesiologist's part in managing these procedures, from the start of the intervention through the immediate postoperative period. First concerns are to assure patient safety during transfer, maintain the airway, keep the patient immobile and hemodynamically stable, and manage anticoagulant and antiplatelet treatments. Rapid awakening must also be assured so that the patient's neurologic status can be assessed in situ. The anesthesiologist should treat any neurologic complications that develop and that might lead to emergency situations during the procedures.

Indications for carotid artery surgery and stent: the role of carotid ultrasound

Carotid artery disease is the most frequently identified cause of ischemic stroke and is mostly due to atherosclerotic disease. Landmark trials have demonstrated that surgical intervention in cases of high-grade carotid stenosis can reduce the risk of subsequent stroke. Endovascular approaches continue to be evaluated in ongoing trials. Careful patient selection is critical if the potential benefits of carotid revascularization are to be realized. Ultrasound is a safe, accurate, readily available method to evaluate carotid artery disease. The degree of stenosis is the parameter most frequently used to make decisions about therapeutic approaches. Plaque characteristics may also be useful for identifying high-risk patients. Microembolic signals detected by transcranial Doppler ultrasound can identify cerebral embolization before or after carotid intervention. This review discusses the current clinical role of carotid ultrasound in the selection of patients for the two most frequently used carotid interventions: carotid endarterectomy or carotid angioplasty and stenting.

Timing of stenting of symptomatic carotid stenosis is predictive of 30-day outcome

For patients with symptomatic carotid stenosis, benefit from carotid artery stenting (CAS) highly depends on the 30-day stroke and death rates. Identification of predictors of unfavourable outcome would help guide the patient selection. We analysed the influence of clinical and angiographic factors on the 30-day outcomes of 77 consecutive patients who underwent CAS for > or = 60% symptomatic carotid stenosis within 180 days of transient ischaemic attack or moderate stroke (modified Rankin Scale score < or = 3). The 30-day composite end-point for stroke (7.8%) and death of any cause (1.3%) was 9.1%. Patients with complicated CAS were older than patients with uncomplicated CAS (mean age 75.1 +/- 8.2 vs. 65.9 +/- 9.5 years, P = 0.015) and underwent stenting significantly earlier after the qualifying event: median delay 1.5 weeks (range: 0.2-3.0) vs. 3.2 weeks (range: 0.5-26), P = 0.004. In multivariate logistic regression analyses, age [odds ratio (OR) = 1.148; 95% confidence interval (CI): 1.011-1.304 and P = 0.033] and delay of treatment < 2 weeks (OR = 22.399; 95% CI: 2.245-223.445 and P = 0.008) remained the only variables significantly associated with 30-day outcome. CAS carries a considerable risk in old patients and when performed early (< 2 weeks) after the qualifying event. Future reports should address the timing of CAS.

Impact of Diabetes, Patient Age, and Gender on the 30-Day Incidence of Stroke and Death in Patients Undergoing Carotid Artery Stenting with Embolus Protection: A Post-Hoc Subanalysis of a Prospective Multicenter Registry

PURPOSE

To assess the impact of diabetes, patient age, and gender on major periprocedural (30-day) complications (major and minor strokes, all-cause deaths) following carotid artery stenting (CAS).

METHODS

An exploratory analysis was performed of 695 patients (516 men; mean age 69.9+/-8.4 years) enrolled consecutively between September 1999 and September 2002 in a multicenter Italian/German registry of routine CAS using cerebral protection devices. There were 535 nondiabetic patients and 160 diabetic patients in the analysis.

RESULTS

Logistic regression analysis revealed that diabetes and age, but not gender, impacted the cumulative 30-day incidence of any stroke and death (OR 2.1, 95% CI 1.0 to 4.8, p = 0.068 and OR 1.06, 95% CI 1.01 to 1.12, p = 0.031, respectively), as well as the 30-day incidence of major strokes and deaths (OR 5.9, 95% CI 1.6 to 21.8, p = 0.007 and OR 1.13, 95% CI 1.02 to 1.25, p = 0.018, respectively). According to receiver-operating characteristic analysis, age had no discriminatory power to predict complications in nondiabetic patients, but an age of 75 years was identified as the optimal cut point to predict complications in diabetic patients. Compared with nondiabetic patients, diabetics > or =75 years had a 4.3 greater risk of experiencing any stroke or death (95% CI 1.3 to 12.3, p = 0.016) and a 12.0 greater risk of a major stroke or death (95% CI 2.1 to 66.5, p = 0.005). Diabetics <75 years had no increase in risk over that of nondiabetic patients.

CONCLUSION

Diabetic patients > or =75 years carry a significantly increased risk for strokes or death after protected CAS. The findings should be taken into consideration when treating elderly diabetic patients.

Carotid intervention 3: the evidence for cerebral protection

Carotid stenting is a safe alternative option to conventional carotid endarterectomy in the treatment of carotid artery stenosis in patients considered poor candidates for surgery or who choose not to have open surgery. During the stenting procedure, however, distal embolization may occur with neurological sequelae. To reduce the incidence of this, several cerebral-protection devices (CPDs) have been developed. Different types of CPDs are now commercially available: distal occlusion balloons, distal filters, and proximal protection devices with or without reversal of flow. But complications can occur with their use and are usually associated with an inability to cross the lesion, failure to capture the emboli, vasospasm, and vessel wall injury. Because protection devices are currently the focus of interest by manufacturers and physicians, several trials are going on worldwide to analyze the characteristics of each of them and to evaluate their efficacy in reducing the rate of distal embolization.

Outcome of carotid endarterectomy and stent insertion based on grading of carotid endarterectomy risk: a 7-year prospective study

Object

The authors of this study prospectively compared periprocedural neurological morbidity and the appearance of lesions on diffusion-weighted (DW) magnetic resonance (MR) imaging in patients who had undergone carotid endarterectomy (CEA) or carotid artery stent placement (CASP) with distal balloon protection, based on a CEA risk grading scale.

Methods

Patients undergoing CEA (139 patients) and CASP (92 patients) were classified into Grades I to IV, based on the presence of angiographic (Grade II), medical (Grade III), and neurological (Grade IV) risks. Although not randomized, the CEA and CASP groups were well matched in terms of the graded risk factors except for a greater proportion of neurologically unstable patients in the CEA group (11 compared with 3%, p = 0.037). There were greater proportions of asymptomatic (64 compared with 34%, p = 0.006) and North American Symptomatic Carotid Endarterectomy Trial–ineligible patients (29 compared with 14%, p < 0.0001) in the CASP group. The overall rates of neurological morbidity with ischemic origin and the appearance of lesions on DW MR imaging after CEA were 2.2 and 9.3%, and those after CASP were 7.6 and 35.9% (nondisabling stroke only), respectively. The only disabling stroke was caused by an intracerebral hemorrhage attributable to hyperperfusion in one case (0.7%) of CEA. There were no deaths. There was no significant association between neurological morbidity and the risk grade in patients who had undergone CEA, although the incidence of lesions on DW imaging was significantly greater in the Grade IV risk group compared with that in the other risk groups combined (42.1 compared with 4.2%, p < 0.0001). After CASP, a higher incidence of neurological morbidity and lesions on DW imaging was noted for the Grade II and III risk groups combined as compared with that in the Grade I risk group, regardless of a symptomatic or an asymptomatic presentation (neurological morbidity: 10.5 compared with 3.1%, respectively, p = 0.41; and DW imaging lesions: 47.4 compared with 19.4%, p = 0.01). The incidence of lesions on DW imaging after CEA was significantly lower than that after CASP except for the Grade IV risk groups.

Conclusions

Despite a higher incidence of DW imaging–demonstrated lesions in the Grade IV risk group, there was no significant association between the risk group and neurological morbidity rates after CEA. The presence of vascular and medical risk profiles conferred higher rates of neurological morbidity and an increased incidence of lesions on DW imaging after CASP. Considering that no serious nonneurological complications were noted, CEA and CASP appear to be complementary methods of revascularization for carotid artery stenosis with various risk profiles.

Statin Therapy at Carotid Angioplasty and Stent Placement: Effect on Procedure-related Stroke, Myocardial Infarction, and Death

PURPOSE

To retrospectively determine if preprocedural statin treatment is associated with a reduction of cardiovascular events after carotid angioplasty and stent placement (CAS) in patients with symptomatic carotid stenosis.

MATERIALS AND METHODS

A study resulting in a prospective database was approved by the institutional ethics review board; written informed consent was obtained. The approval and informed consent included future retrospective analysis. Consecutive patients (n = 180) from the prospective database underwent CAS for high-grade symptomatic carotid disease. The frequency of cardiovascular complications (composite of stroke, myocardial infarction, and death within 30 days after CAS) between 127 patients without preprocedural statin treatment and that of 53 patients with preprocedural statin treatment at CAS were compared with chi2 and multivariate logistic regression analysis.

RESULTS

The overall 30-day myocardial infarction rate was two of 180 (1%) patients, the minor stroke rate was 16 of 180 (9%) patients, the major stroke rate was one of 180 (0.5%) patients, and the death rate was two of 180 (1%) patients. The incidence of cardiovascular events (composite of stroke, myocardial infarction, and death within 30 days after CAS) was significantly different between patients with preprocedural treatment (4%) and those without preprocedural statin treatment (15%) (P < .05). These higher complication rates among patients without preprocedural statin treatment were not mediated by adjustment for age, sex, other baseline characteristics, degree of carotid stenosis, use of cerebral protection devices, or the year in which CAS was performed.

CONCLUSION

Preprocedural statin therapy appears to reduce the incidence of stroke, myocardial infarction, and death within 30 days after CAS. Future prospective randomized trials are warranted to further assess this potential protective effect of statin drugs during carotid interventions.

Rapid measurement of S-100B serum protein levels by Elecsys S100 immunoassay in patients undergoing carotid artery stenting or endarterectomy

OBJECTIVES

This study was designed to apply the rapid Elecsys S100 immunoassay for real-time measurement of S100 protein serum levels indicating acute brain damage in patients undergoing carotid artery stenting (CAS) or endarterectomy (CEA).

DESIGN AND METHODS

Data of 14 CAS patients were compared to those of 43 CEA and 14 control patients undergoing coronary angiography (CA). S100 serum levels were measured by the full-automatic Elecsys S100 immunoassay and compared to those obtained by the well-established LIA-mat S100 system.

RESULTS

In contrast to CAS and CA patients, median S100 serum levels of CEA patients significantly increased to 0.24 ng/mL before declamping, but subsequently returned to baseline. Three CEA patients with neurological deficits showed sustained elevated S100 levels 6 h after extubation. Absolute S100 values were not significantly different between the two methods. Bland-Altman plot analyses displayed a good agreement, mostly indicating slightly smaller values applying the Elecsys S100 system.

CONCLUSIONS

The Elecsys S100 system appears to be suitable for rapid real-time detection of neurological deficits in patients undergoing CAS and CEA. Persistent elevations of Elecsys S100 levels during CEA were associated with prolonged neurological disorders, whereas transient increases seem to represent impaired blood-brain barrier integrity without neurological deficits.

Incidence and risk factors for medical complications after carotid artery stenting

OBJECTIVE

Carotid angioplasty and stenting (CAS) is being evaluated as an alternative to carotid endarterectomy for the treatment of carotid artery stenosis; however, to date little is known about the incidence of medical complications after CAS. The goal of this study was to determine the frequency of, and to identify potential clinical risk factors for, the development of medical complications after CAS.

METHODS

Medical complications that occurred < or = 30 days after CAS in 327 consecutive patients (241 men, 86 women; mean age, 69 +/- 9 years; range, 45 to 90 years) treated for symptomatic (n = 182, 56%) or asymptomatic (n = 145, 44%) carotid artery stenosis were recorded. The effect of clinical characteristics on the subsequent development of medical complications was analyzed by logistic regression.

RESULTS

Fifty-one patients (15%) had 62 medical complications: 3 (0.9%) myocardial infarctions, 3 (0.9%) cardiac arrhythmias, 4 (1.2%) episodes of angina pectoris, 3 (0.9%) episodes of symptomatic hypertension, 16 (4.9%) episodes of symptomatic hypotension, 10 (3.1%) chest infections, 9 (2.7%) had periods of confusion, 5 (1.5%) had urinary retention, and 9 (2.7%) urinary tract infections. One chest infection was fatal and 16 complications prolonged the intensive care unit monitoring period > 24 hours. Advanced age (odds ratio [OR], 1.1; 95% confidence interval [CI], 1.05 to 1.14) and a symptomatic carotid stenosis (OR, 2.1; 95% CI, 1.07 to 4.1) independently predicted the occurrence of medical complications.

CONCLUSION

Although life-threatening or fatal non-neurologic events were uncommon in this series, the overall incidence of medical complications after CAS might be higher than currently anticipated. Older and symptomatic patients are at the highest risk, and these subgroups should be monitored closely.

Diagnosis and prevention of atherosclerotic cerebral infarction

Atherosclerotic disease accounts for approximately 25% of ischemic strokes. Atherosclerotic stroke is caused mainly by embolic events from the carotid artery bifurcation or the aortic arch, although intracranial thrombosis can occur, more often in African Americans, Asians, and diabetes patients. Primary prevention of stroke is critical for patients with risk factors for atherosclerosis, including hypertension, diabetes, smoking and hypercholesterolemia. Stroke can be prevented in patients with established atherosclerotic disease by identification and management of patients with carotid artery stenosis by non-invasive testing. Particular attention must be paid to patients with transient symptoms of brain ischemia.

Carotid Angioplasty with or without Stent Placement versus Carotid Endarterectomy for Treatment of Carotid Stenosis: A Meta-analysis

OBJECTIVE:

Carotid angioplasty with or without stent placement (CAS) has been proposed as an alternative method to carotid endarterectomy (CEA) for treatment of carotid stenosis. Small randomized trials have evaluated the comparative efficacy of both methods; however, definitive evidence is lacking.

METHODS:

A search was made for randomized clinical trials comparing CAS and CEA for treatment of carotid stenosis. A literature search of MEDLINE, PubMed, and Cochrane databases was supplemented by a review of bibliographies of relevant articles and personal files. A meta-analysis was performed using a random effects model because significant heterogeneity was observed. Outcomes compared included 1-month composite rates of stroke or death, all strokes, disabling strokes, myocardial infarction, cranial nerve injury, and major bleeding and 1-year rates of both minor and major ipsilateral strokes.

RESULTS:

We analyzed five randomized trials totaling 1154 patients (577 randomized to CEA and 577 randomized to CAS). The composite end point of 1-month stroke or death rate was not different between patients treated with CAS compared with those treated with CEA (relative risk [RR], 1.3; 95% confidence interval [CI], 0.6–2.8; P = 0.5). The 1-month stroke rate (831 patients analyzed: RR, 1.3; 95% CI, 0.4–3.6; P = 0.7) and disabling stroke rate (831 patients analyzed: RR, 0.9; 95% CI, 0.2–3.5; P = 0.9) was similar for CAS and CEA. The 1-month rates of myocardial infarction (814 patients analyzed: RR, 0.3; 95% CI, 0.1–0.9) and cranial nerve injury (918 patients analyzed: RR, 0.05; 95% CI, 0.01–0.3) were significantly lower for CAS. No significant differences were observed in 1-year rates of ipsilateral stroke (814 patients analyzed: RR, 0.8; 95% CI, 0.5–1.2; P = 0.2).

CONCLUSION:

The 30-day stroke and death rates associated with CAS and CEA were not significantly different. Lower rates of myocardial infarction and cranial nerve injury were observed with CAS compared with CEA.

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.

Comparison of angioplasty and stenting with cerebral protection versus endarterectomy for treatment of internal carotid artery stenosis in elderly patients

PURPOSE

Carotid angioplasty and stenting (CAS) is being evaluated as an alternative to carotid endarterectomy (CEA) for treatment of severe carotid artery stenosis. Because CAS does not require general anesthesia and is less traumatic, it might be especially advantageous in older patients, but data comparing these 2 treatment methods in older patients are scarce.

METHODS

The periprocedural complication rates in 53 patients aged 75 years or older who had undergone protected CAS between June 2001 and April 2004 were compared with those in a group of 110 patients aged 75 years or older who had undergone CEA between January 1997 and December 2001, before widespread introduction of CAS procedures at our institution. All patients were evaluated by a neurologist both before and after surgery. According to the criteria set forth by the large trials the occurrence of minor, major, or fatal stroke, and myocardial infarction within 30 days was determined.

RESULTS

The demographic characteristics and indications for an intervention were similar in both treatment groups. Thirty patients (57%) in the CAS group had symptomatic carotid stenosis, compared with 69 patients (63%) in the CEA group. In neither group was there any fatal stroke or myocardial infarction. The 30-day stroke rate was significantly higher in the CAS group (4 minor, 2 major strokes; 11.3%) than in the CEA group (no minor, 2 major strokes; 1.8%; P < .05). Although the 30-day major stroke rate between CAS and CEA groups was comparable (3.8% vs 1.8%; P = 0.6), this effect was mainly attributable to a significantly higher rate of minor stroke in the CAS group (7.5% vs 0%; P < .05).

CONCLUSION

Despite the use of cerebral protection devices the neurologic complication rate in patients aged 75 years and older associated with CAS was significantly higher than with CEA performed by highly skilled surgeons at our academic institution. Although this finding is mainly based on a significantly higher rate of minor stroke in the CAS group, the common practice of preferentially submitting older patients to CAS is questionable, and should be abandoned until the results of further randomized trials are available.

Carotid artery surgery vs. stent: A cardiovascular perspective

Stroke is a major health catastrophe that is responsible for the third most common cause of death and the leading cause of disability. Carotid artery stenosis is an important cause of brain infarctions and the risk of stroke is directly related to the severity of carotid artery stenosis and to the presence of symptoms. Familiarity with different methods of measuring degrees of carotid artery stenosis is a key in understanding the role of revascularization of this disorder. Carotid endarterectomy (CEA), surgical removal of the carotid atherosclerotic plaque, is intended to prevent stroke in patients with carotid artery stenosis and currently the most commonly performed vascular procedure in the United States. Several randomized clinical trials had demonstrated the benefits of CEA in selected groups of patients with symptomatic and asymptomatic carotid artery stenosis. However, CEA can cause stroke, the very thing it intended to prevent, and is associated with significant perioperative complications such as those related to general anesthesia, cardiac or nerve injury. Moreover, several anatomical and medical conditions may limit candidates for CEA. Carotid artery stenting (CS) is an evolving and less invasive technique for carotid artery revascularization. Recent studies demonstrated that CS with embolic protection devices has become an alternative to CEA for high-surgical-risk patients and the procedure of choice for stenoses inaccessible by surgery. The role of CS in low risk patients awaits the completion of several ongoing studies.

Use of a large angioplasty balloon for predilation is a risk factor for embolic complications in protected carotid stenting

Periprocedural neurological complications (PNCs) after carotid stenting were retrospectively analyzed to determine the risk factors with the use of various protective devices. Forty-three lesions in 40 patients were treated by carotid stenting with distal balloon protection for nearly all postdilation procedures and some predilation procedures. The following variables were statistically analyzed for association with PNCs: diameter of the angioplasty balloon used for predilation, use of a distal protection balloon during predilation, use of a protection balloon during postdilation, lesion-bifurcation distance, length of the lesion, age, clinical presentation of the lesion (symptomatic or asymptomatic), and hypercholesterolemia. PNCs occurred in five patients, four with minor deficits and one with major deficits. Univariate analysis showed large diameter of the predilation angioplasty balloon (p = 0.0026), use of a protection balloon during predilation (p = 0.0075), lesion length (p = 0.0003), and lesion-bifurcation distance (p = 0.0006) were significantly associated with PNCs. Multivariate analysis of these four variables showed that use of a large angioplasty balloon for predilation was the only independent predictor (p = 0.004, odds ratio 34.00) for the occurrence of PNCs. Use of a large angioplasty balloon for predilation carries the risk of periprocedural embolic complications. Therefore, even when a protection device is used, predilation should be performed with a small balloon.

Buffalo Metropolitan Area and Erie County Stroke Study: Rationale, Design, and Methods

OBJECTIVES

The primary objective of this study was to define the incidence, disability, and death associated with stroke in the Buffalo metropolitan area and Erie County. This area has the highest stroke rate in New York State and therefore represents an ideal site to develop a successful model for prevention and management of stroke.

DESIGN

A cross-sectional design to study all new and recurrent strokes that occurred in the calendar year 2000 in the geographical location of Buffalo metropolitan area and Erie County. PATIENTS AND DATA COLLECTED: A retrospective review of an estimated 5,000 patients with new stroke will be performed at regional hospitals and the coroner's office to determine the stroke subtypes, cerebrovascular risk factors, diagnostic investigations, treatment provided, and outcome. The total population residing in Buffalo in the year 2000 is available through the recent census. The study will also evaluate the quality of care provided for stroke patients including effectiveness of primary and secondary stroke prevention measures within this geographical region.

CONCLUSIONS

We believe that this information will assist in allocation of resources and implementation of steps to improve stroke prevention and treatment.

Thalamic hemorrhage following carotid angioplasty and stenting

Carotid angioplasty and stenting (CAS) has emerged as an alternative treatment of carotid stenosis for patients poorly suited for endarterectomy. Intracerebral hemorrhage following carotid revascularization is rare and thought to be related to hyperperfusion injury in most cases. Early experience suggests an increased incidence of hemorrhage following CAS as compared to endarterectomy. We describe a patient who suffered a thalamic hemorrhage following CAS. Because this hemorrhage occurred in a vascular territory unlikely to have been supplied by the treated artery, this case suggests that the mechanism of intracerebral hemorrhage following CAS may in some cases be different from the hyperperfusion hemorrhage classically described following endarterectomy.

Endovascular treatment of cerebrovascular diseases and intracranial neoplasms

Cerebrovascular diseases are an important cause of morbidity and mortality worldwide. Endovascular treatment has emerged as a minimally invasive approach to treat cerebrovascular diseases and possibly intracranial neoplasms. Practice patterns for selection of patients for endovascular treatment are continuously being modified on the basis of new information derived from clinical studies. In this review, I discuss the various endovascular treatments for diseases such as ischaemic stroke, carotid and intracranial stenosis, intracranial aneurysms, arteriovenous malformations, malignant gliomas, and meningiomas.

Safety of High-dose Intravenous Eptifibatide as an Adjunct to Internal Carotid Artery Angioplasty and Stent Placement: A Prospective Registry

OBJECTIVE

Eptifibatide, a competitive platelet glycoprotein IIb-IIIa receptor inhibitor with high selectivity for platelet glycoprotein IIb-IIIa receptors and a short half-life, has been shown to reduce the risk of ischemic events associated with coronary interventions, particularly when used in high doses. However, its role in conjunction with neurointerventional procedures needs to be determined. We report the results of an open-label prospective registry to evaluate the safety (in terms of avoiding hemorrhagic complications) and effectiveness (in terms of preventing ischemic complications such as stroke) of administering high-dose eptifibatide during internal carotid artery angioplasty and stent placement (CAS) for extracranial carotid artery stenosis.

METHODS

After femoral artery access was established and intravenous heparin (30 U/kg bolus) was administered, each patient was administered intravenous eptifibatide (two 180-μg/kg single-dose boluses before CAS, then a 2.0-μg/kg/min infusion for 20–24 hours thereafter). The primary end point was the 30-day composite occurrence of death, cerebral infarction, and unplanned or urgent endovascular or surgical intervention. The primary safety end point was bleeding, for which complications were classified according to the Thrombolysis in Myocardial Infarction scheme as major (hemoglobin decrease of more than 5 g/dl), minor (hemoglobin decrease of 3–5 g/dl), or insignificant. Platelet aggregation was measured in 13 consecutive patients with a rapid platelet-function analyzer.

RESULTS

Twenty-six patients (mean age, 68.1 ± 9.4 yr; 16 men) underwent treatment. The infusion and the CAS procedure were discontinued in one patient who developed angioneurotic edema after being administered intravenous heparin and the first bolus dose of eptifibatide. Among the 25 patients who underwent the procedure, no intracerebral hemorrhages and one minor ischemic stroke occurred during the 1-month follow-up period. The minor stroke was observed on postprocedure Day 7 in a patient for whom antiplatelet therapy was discontinued before a coronary artery bypass graft operation was performed. Another patient was discharged after an uncomplicated hospitalization but died as a result of urinary sepsis 12 days after CAS. One episode of major bleeding from the femoral insertion site required surgical repair and blood transfusions. Minor bleeding occurred in one patient. Platelet aggregation measurements obtained in 13 patients revealed a high degree (mean, 96%; range, 86–100%) of platelet inhibition after the administration of the second bolus dose of intravenous eptifibatide.

CONCLUSION

High-dose eptifibatide administered as an adjunct to CAS seems to be safe. Further studies are required to analyze its effectiveness and role in neurointerventional procedures.