Early carotid endarterectomy after non-disabling ischaemic stroke: adequate therapeutical option in selected patients

Systematic Review of the Operative Risks of Carotid Endarterectomy for Recently Symptomatic Stenosis in Relation to the Timing of Surgery

Background and Purpose— Reliable data on the risk of carotid endarterectomy (CEA) in relation to timing of surgery are necessary to plan CEA most effectively, to adjust risks for case-mix, and to understand the mechanisms of operative stroke.

Methods— We performed a systematic review of all studies published from 1980 to 2008 inclusive that reported the risk of stroke and death due to CEA in relation to the time between presenting symptom and surgery. Pooled estimates of risk by the time since the last event were obtained by Mantel–Haenszel meta-analysis.

Results— Of 494 published operative series, only 47 stratified risk by timing of surgery. The pooled absolute risks of stroke and death after urgent CEA were high in patients with stroke-in-evolution (20.2%, 95% CI 12.0 to 28.4) and in patients with crescendo TIA (11.4%, 6.1 to 16.7), with no trends toward reduced risks in more recent studies. However, there was no significant difference between early and later CEA in neurologically stable patients with recent TIA or nondisabling stroke (<1 week versus ≥1 week, OR=1.2, 0.9 to 1.7, P =0.17; <2 weeks versus ≥2 weeks, OR=1.2, 0.9 to 1.6, P =0.13).

Conclusions— Emergency endarterectomy for stroke-in-evolution has a high operative risk, but the risk may be somewhat lower in patients with crescendo TIA. Surgery in the first week in neurologically stable patients with TIA or minor stroke is not associated with a substantially higher operative risk than delayed surgery. More data are required on the risk and benefit of more urgent surgery for TIA and minor stroke and for early versus delayed surgery in patients with major nondisabling stroke.

Guidelines for the Early Management of Adults With Ischemic Stroke

Purpose— Our goal is to provide an overview of the current evidence about components of the evaluation and treatment of adults with acute ischemic stroke. The intended audience is physicians and other emergency healthcare providers who treat patients within the first 48 hours after stroke. In addition, information for healthcare policy makers is included.

Methods— Members of the panel were appointed by the American Heart Association Stroke Council’s Scientific Statement Oversight Committee and represented different areas of expertise. The panel reviewed the relevant literature with an emphasis on reports published since 2003 and used the American Heart Association Stroke Council’s Levels of Evidence grading algorithm to rate the evidence and to make recommendations. After approval of the statement by the panel, it underwent peer review and approval by the American Heart Association Science Advisory and Coordinating Committee. It is intended that this guideline be fully updated in 3 years.

Results— Management of patients with acute ischemic stroke remains multifaceted and includes several aspects of care that have not been tested in clinical trials. This statement includes recommendations for management from the first contact by emergency medical services personnel through initial admission to the hospital. Intravenous administration of recombinant tissue plasminogen activator remains the most beneficial proven intervention for emergency treatment of stroke. Several interventions, including intra-arterial administration of thrombolytic agents and mechanical interventions, show promise. Because many of the recommendations are based on limited data, additional research on treatment of acute ischemic stroke is needed.

Guidelines for the early management of adults with ischemic stroke: a guideline from the American Heart Association/American Stroke Association Stroke Council, Clinical Cardiology Council, Cardiovascular Radiology and Intervention Council, and the Atherosclerotic Peripheral Vascular Disease and Quality of Care Outcomes in Research Interdisciplinary Working Groups: the American Academy of Neurology affirms the value of this guideline as an educational tool for neurologists

PURPOSE

Our goal is to provide an overview of the current evidence about components of the evaluation and treatment of adults with acute ischemic stroke. The intended audience is physicians and other emergency healthcare providers who treat patients within the first 48 hours after stroke. In addition, information for healthcare policy makers is included.

METHODS

Members of the panel were appointed by the American Heart Association Stroke Council's Scientific Statement Oversight Committee and represented different areas of expertise. The panel reviewed the relevant literature with an emphasis on reports published since 2003 and used the American Heart Association Stroke Council's Levels of Evidence grading algorithm to rate the evidence and to make recommendations. After approval of the statement by the panel, it underwent peer review and approval by the American Heart Association Science Advisory and Coordinating Committee. It is intended that this guideline be fully updated in 3 years.

RESULTS

Management of patients with acute ischemic stroke remains multifaceted and includes several aspects of care that have not been tested in clinical trials. This statement includes recommendations for management from the first contact by emergency medical services personnel through initial admission to the hospital. Intravenous administration of recombinant tissue plasminogen activator remains the most beneficial proven intervention for emergency treatment of stroke. Several interventions, including intra-arterial administration of thrombolytic agents and mechanical interventions, show promise. Because many of the recommendations are based on limited data, additional research on treatment of acute ischemic stroke is needed.

What sense lies in antisense inhibition of inducible nitric oxide synthase expression?

The impact of nitric oxide (NO) synthesized after activation by proinflammatory cytokines and/or bacterial products by an inducible NO synthase (iNOS) is still contradictory. Expression of iNOS in inflammatory reactions is often found predominantly in cells of epithelial origin, and in these cases NO may serve as a protective agent limiting pathogen spreading, downregulating local inflammatory reactions by inducing production of Th2-like responses in a classical feedback circle, or limiting tissue damage during stress conditions. However, an abundant amount of data on chronic human disorders with predominant proinflammatory Th1-like reactions points to a destructive role of iNOS activity calling for a specific inhibition. Various methods to inhibit iNOS have been established to elucidate a protective versus a destructive role of NO during various stresses. In this review, we focus on antisense (AS)-mediated gene knock-down as a relatively new method to inhibit NO production and summarize the techniques applied and their successes. At least in theory, it provides a specific, rapid, and potentially high-throughput method for inhibiting gene expression and function. We here discuss the opportunities of iNOS-directed AS-ODN, and extensively deal with limitations and experimental problems.

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.

Early Carotid Surgery in Acute Stroke: A Multicentre Randomised Pilot Study

BACKGROUND

Standard practice has been to delay carotid endarterectomy (CEA) for 2 months following acute stroke to avoid a perceived risk of cerebral haemorrhage. We investigated whether early CEA reduces early recurrent stroke and improves outcome in partial anterior circulation infarction (PACI).

METHODS

Patients with PACI and a Barthel score of >18 before stroke underwent carotid duplex and CT imaging within 7 days of stroke. Forty consenting patients fit for surgery with greater than 70% ipsilateral carotid stenosis were randomised, 19 to 'early' (within 24 h) and 21 to 'delayed' surgery (at 8 weeks). Modified Rankin and Barthel scores were recorded at 1 week, 2 months, 6 and 12 months.

RESULTS

Rankin scores improved more rapidly following 'early' surgery to a score of 1 (0-4) at 2 and 6 months compared with 2.5 and 2 (1-4), respectively, for delayed surgery (p < 0.05). Barthel scores were also significantly improved following 'early' CEA at 7 days but both groups reached a median score of 20 by 2 months. Four 'delayed' and 3 'early' patients suffered extension or recurrence of neurological deficits with 1 death in each group.

CONCLUSIONS

Early CEA within 7 days of ischaemic stroke improved functional outcome with earlier hospital discharge. A large multicentre study is needed to exclude the possibility that 'early' CEA increases the risk of cerebral haemorrhage or death.

Systematic review of the risks of carotid endarterectomy in relation to the clinical indication for and timing of surgery

BACKGROUND AND PURPOSE

Reliable data on the risk of carotid endarterectomy (CEA) in relation to clinical indication and timing of surgery are necessary to target CEA more effectively, to inform patients, to adjust risks for case mix, and to understand the mechanisms of operative stroke.

METHODS

We performed a systematic review of all studies published from 1980 to 2000 inclusive that reported the risk of stroke and death resulting from CEA. Pooled estimates of risk by type of presenting ischemic event and time since the last event were obtained by Mantel-Haenszel meta-analysis.

RESULTS

Of 383 published studies, only 103 stratified risk by indication. Although the operative risk for symptomatic stenosis overall was higher than for asymptomatic stenosis (odds ratio [OR], 1.62; 95% confidence interval [CI], 1.45 to 1.81; P<0.00001; 59 studies), risk in patients with ocular events only tended to be lower than for asymptomatic stenosis (OR, 0.75, 95% CI, 0.50 to 1.14; 15 studies). Operative risk was the same for stroke and cerebral transient ischemic attack (OR, 1.16; 95% CI, 0.99 to 1.35; P=0.08; 23 studies) but higher for cerebral transient ischemic attack than for ocular events only (OR, 2.31; 95% CI, 1.72 to 3.12; P<0.00001; 19 studies) and for CEA for restenosis than primary surgery (OR, 1.95; 95% CI, 1.21 to 3.16; P=0.018; 6 studies). Urgent CEA for evolving symptoms had a much higher risk (19.2%, 95% CI, 10.7 to 27.8) than CEA for stable symptoms (OR, 3.9; 95% CI, 2.7 to 5.7; P<0.001; 13 studies), but there was no difference between early (<3 to 6 weeks) and late (>3 to 6 weeks) CEA for stroke in stable patients (OR, 1.13; 95% CI, 0.79 to 1.62; P=0.62; 11 studies). All observations were highly consistent across studies.

CONCLUSIONS

Risk of stroke and death resulting from CEA is highly dependent on the clinical indication. Audits of risk should be stratified accordingly, and patients should be informed of the risk that relates to their presenting event.

Overview of the principal results and secondary analyses from the European and North American randomised trials of endarterectomy for symptomatic carotid stenosis

OBJECTIVES

Review of the primary results and secondary analyses from the European Carotid Surgery Trial (ECST) and the North American Symptomatic Carotid Endarterectomy Trial (NASCET).

DESIGN

Review of 48 ECST and NASCET papers.

RESULTS

The simple assumption that all patients with a symptomatic stenosis >70% benefit from CEA is untenable. Approximately 70-75% will not have a stroke if treated medically. The ECST and NASCET have identified subgroups that should have expedited investigation and surgery (male sex, age >75 years, 90-99% stenosis, irregular plaque, hemispheric symptoms, recurrent events for >6 months, contralateral occlusion, multiple co-morbidity). Accordingly development of local protocols for patient selection/exclusion should involve surgeons and physicians and take account of the local operative risk. The ECST and NASCET have also shown that the ubiquitous "string sign" is not associated with a high risk of stroke, and emergency CEA is unnecessary.

CONCLUSIONS

Surgeons must quote their own results and be aware that a high operative risk reduces long-term benefit. Accordingly, in those centres with a higher operative death/stroke rate, some "lower risk" patients should probably be considered for best medical therapy alone. It is hoped that pooling of the ECST and NASCET databases will enable more definitive guidelines to be developed regarding who benefits most from CEA.

Early versus delayed carotid endarterectomy after a nondisabling ischemic stroke: a prospective randomized study

BACKGROUND

Although many retrospective and a few prospective studies have analyzed the outcome of early and delayed carotid endarterectomy (CEA) after a recent minor or nondisabling stroke (ie, a minimal and stabilized focal neurologic deficit of acute onset persisting for more than 24 hours and not leading to a handicap or to a significant impairment of daily living activities), the optimal timing of surgery remains uncertain. The purpose of this study was to prospectively compare the perioperative death and stroke rates of CEA performed within 30 days (early group) or more than 30 days (delayed group) after a nondisabling ischemic stroke in patients with carotid bifurcation disease.

METHODS

During a 4-year period, of 86 patients experiencing a minor stroke, 45 were randomized to undergo early CEA and 41 to undergo delayed CEA. All patients underwent preoperative cerebral computed tomography, duplex ultrasonographic scanning and angiography of the supra-aortic trunks. All CEAs were carotid eversion endarterectomies and were performed by the same surgeon, using deep general anesthesia, with continuous electroencephalographic monitoring for the selective shunting. The perioperative death and stroke rates were compared between the 2 groups.

RESULTS

No perioperative deaths occurred in either group. No recurrent strokes occurred during the waiting period in the delayed group. The incidence of perioperative stroke was comparable in the 2 groups (1 of 45, 2% vs 1 of 41, 2%). The mean follow-up was 23 months (range, 6 to 50 months). Survival rates after 1, 2, and 3 years were similar in the 2 groups.

CONCLUSIONS

Early CEA after a nondisabling ischemic stroke can be performed safely with perioperative mortality and stroke rates comparable with those of delayed CEA. The timing of surgery does not seem to influence the benefit of the CEA.

Reconstructive surgery of the extracranial arteries

The first carotid endarterectomy (CEA) is usually accredited to Eastcott who reported in 1954 the successful incision of a diseased carotid bulb with end-to-end anastomosis of the internal carotid artery (ICA) to the common carotid artery (CCA). During the following years surgeons were quick to adopt and improve the intuitively attractive procedure. But by the early to mid 1980s several leading neurologists began to question the growing number of CEAs performed at that time. Six major CEA trials were then designed which are now completed or nearing completion. Most conclusive data are available from the North American Symptomatic Carotid Endarterectomy Trial (NASCET) for symptomatic carotid disease, and from the Asymptomatic Carotid Atherosclerosis Study (ACAS) for asymptomatic carotid disease. The key result of these studies is that CEA is beneficial to high grade symptomatic and asymptomatic carotid stenosis. While the benefit in symptomatic disease is clear, it may be negligible in asymptomatic patients suffering from other medical conditions, the most important being coronary artery disease. Since the conclusions from the different studies vary significantly, guidelines and recommendations with regard to CEA have been issued by a number of interest groups, so-called consensus conferences. The best known guidelines are published by the American Heart Association (AHA). However, the practice of interest groups to issue guidelines is currently being criticized, the main reason being that interest groups have different ideas and all claim the right to issue guidelines. At present we recommend CEA for symptomatic high-grade stenosis in patients without significant coincident disease. With regard to asymptomatic stenosis we suggest surgery to otherwise healthy patients if the stenosis is very narrow or progressive. Preoperative evaluation has changed over the years. Currently we recommend duplex sonography in combination with intra- and extracranial magnetic resonance angiography (MRA). Concurrent coronary artery disease is a major consideration in the perioperative management, and the use of a specific algorithm is recommended. Surgery is performed under general anaesthesia with intraoperative monitoring such as electroencephalography (EEG) and transcranial Doppler (TCD). A temporary intraluminal shunt is used selectively if after cross-clamping the flow velocity in the middle cerebral artery (MCA) falls to below 30 to 40% of baseline. For years we employed routine barbiturate neuroprotection during cross-clamping. At the present time we use barbiturate selectively, if the flow velocity in the MCA falls to below 30 to 40% of baseline and if the use of a temporary intraluminal shunt is not possible due to difficult anatomic conditions. The reason to abandon systematic barbiturate protection was to accelerate recovery from anaesthesia. Our patients are monitored overnight on the ICU or a surveillance unit. Routine hospitalization after surgery is 5 to 7 days with a control duplex sonography being performed prior to discharge. A number of details with regard to surgical technique and perioperative management are a matter of discussion. Our surgical routine is described here step by step. Such management resulted in 6 major complications among the 402 cases with 4 of cardiopulmonary and 2 of cerebrovascular origin. For the future we can expect the development of percutaneous transluminal techniques competing with standard carotid endarterectomy. At the present time several comparative studies are under way. Irrespective of the technical approach to treat carotid stenosis, several other issues have to be clarified before long. One of the major unresolved items is the timing of treatment after completed stroke. In this regard prospective trials need to be performed. Although numerically not as important as carotid stenosis, vertebral artery (VA) and subclavian artery (SA) stenoses are more and more accepted as indication for surgical