Simultaneous carotid endarterectomy and coronary artery bypass surgery in Canada

What’s new in stroke prevention and treatment

This review summarizes the latest results and developments in stroke prevention and acute treatment studies published in 2004 and 2005. In contrast to primary prevention in men, aspirin did not significantly reduce the risk of myocardial infarction or death from cardiovascular causes in women over 45 years of age. Patients with symptomatic intracranial stenosis do not benefit from secondary prevention with oral anticoagulation. Magnetic resonance-based acute stroke studies with recombinant tissue plasminogen activator (rtPA) or with desmoteplase, a new thrombolytic agent, showed similar safety and potential benefit beyond the 3-h time window, as with the established inclusion criteria of rtPA. The surgical trial in intracerebral hemorrhage (STICH) failed to demonstrate any benefit for early operative evacuation of hematoma. The authors aim to provide a wide overview of stroke prevention and acute treatment studies published in 2004 and 2005. Relevant journals were hand-searched to compile a broad, but not comprehensive, summary of innovative and clinically relevant findings. A short critical evaluation at the end of selected reviews should encourage the reader to further reading of studies of interest.

Influence of carotid injury in post-myocardial revascularization surgery and its late evolution

BACKGROUND

Approximately 30% of perioperative CVA of myocardial revascularization surgery (MRS) are a result of carotid injuries, without reduction of risk confirmed by perioperative intervention.

OBJECTIVES

Evaluate the impact of carotid disease and perioperative intervention in patients subjected to MRS.

METHODS

Observational, retrospective study, evaluating 1169 patients aged > 69 years undergoing MRS from January, 2006 and December, 2010, monitored, on average, for 49 months. All patients were subjected to ultrasonography of carotids before MRS. It was defined as carotid disease when lesion > 50%. The primary outcome was composed of CVA incidence, transitory ischemic accident (TIA) and death due CVA.

RESULTS

Prevalence of carotid disease was of 19.9% of patients. The incidence of primary outcome between unhealthy and healthy patients was of 6.5% and 3.7%, respectively (p = 0.0018). In the first 30 days, there were 18.2% of events. Were related to carotid disease: renal dysfunction (OR 2.03, IC95% 1.34-3.07; p < 0.01), peripheral arterial disease (OR 1.80, IC95% 1.22-2.65; p < 0.01) and previous myocardial infarction (OR 0.47, IC95% 0.35-0.65; p < 0.01). Regarding the primary outcome, were associated the previous TIA (OR 5.66, IC95% 1.67-6.35; p < 0.01) and renal dysfunction (OR 3.28, IC95% 1.67-6.45; p < 0.01). In patients with lesion >70%, perioperative carotid intervention demonstrated an incidence of 16% in primary outcome compared to 4.3% in conservatory treatment (p = 0.056) with no difference between percutaneous and surgical approaches (p = 0.516).

CONCLUSION

Carotid disease increases the risk of CVA, TIA or death due to CVA in MRS. However, the carotid intervention was not related to reduction of primary outcome.

Patients With Severe Asymptomatic Carotid Artery Stenosis Do Not Have a Higher Risk of Stroke and Mortality After Coronary Artery Bypass Surgery

Background and Purpose—

Stroke development is a major concern in patients undergoing coronary artery bypass grafting (CABG). Whether asymptomatic severe carotid artery stenosis (CAS) contributes to the development of stroke and mortality in such patients remains uncertain.

Methods—

A retrospective analysis of 878 consecutive patients with documented carotid duplex ultrasound who underwent isolated CABG in our institution from January 2003 to December 2009 was performed. Patients with severe CAS (n=117) were compared with those without severe CAS (n=761) to assess the rates of stroke and mortality during hospitalization for CABG. The 30-day mortality rate was also assessed.

Results—

Patients with severe CAS were older and had a higher prevalence of peripheral arterial disease and heart failure. Patients with severe CAS had similar rates of in-hospital stroke (3.4% versus 3.6%; P =1.0) and mortality (3.4% versus 4.2%; P =1.0) compared with patients without severe CAS. The 30-day rate of mortality was also similar between the 2 cohorts (3.4% versus 2.9%; P =0.51).

Conclusions—

Severe CAS alone is not a risk factor for stroke or mortality in patients undergoing CABG. The decision to perform carotid imaging and subsequent revascularization in association with CABG must be individualized and based on clinical judgment.

Current outcomes of simultaneous carotid endarterectomy and coronary artery bypass graft surgery in North America

OBJECTIVE

Management of patients with concomitant carotid and coronary artery disease has been controversial. Divergent strategies have been employed, including simultaneous carotid endarterectomy and coronary bypass (SCC) versus various staged procedures. Although no strict comparison group is available, this study defines current outcomes of SCC, compared qualitatively to two reference categories.

METHODS

Utilizing the STS database from 2003 to 2007, patients who had SCC were compared with patients with cerebrovascular disease who had coronary bypass (CABG) with prior carotid endarterectomy (CEA), and those with carotid Doppler stenosis >75% and no carotid intervention. Logistic regression analysis adjusted for differences in baseline characteristics and operative mortality (OM), and a composite of neurological complications (NC) was assessed.

RESULTS

Of 745,769 patients who underwent isolated CABG with/without CEA, 108,212 (14%) had cerebrovascular disease. Of this group, 5,732 (5%) underwent SCC. The SCC group had more males and lower preoperative risk factors. After statistical adjustment for all baseline differences, SCC had clinically and statistically higher OM and NC compared with any of the reference groups, with 20-40% higher event risk.

CONCLUSIONS

Although no quantitative control group exists for comparison, SCC as recently performed in North America has a high risk compared with any of the reference groups. Suboptimal results associated with the SCC strategy suggest a need for quality improvement and research on the optimal management of patients with simultaneous carotid and coronary disease.

Asymptomatic carotid artery stenosis

Severe asymptomatic carotid stenosis is associated with a stroke risk of approximately 2% per annum. Aggressive management of risk factors is recommended, including cessation of smoking, and treatment of hypertension, diabetes, and hypercholesterolemia. Patients should be treated with antiplatelet agents. Carotid endarterectomy (CEA) in patients with greater than or equal to 60% stenosis reduces the risk of stroke by approximately 1% per annum overall. The benefit is greatest for men and younger patients. There may be no benefit for women or for older patients. Carotid angioplasty and stenting is not recommended as an alternative to CEA until there is clinical trial evidence of efficacy in asymptomatic stenosis, except in some patients with technical contraindications to CEA. There is no evidence that patients with asymptomatic severe carotid stenosis should undergo carotid revascularization prior to other surgical procedures, including coronary bypass surgery.

Surgery Insight: carotid endarterectomy--which patients to treat and when?

Over the past 15 years, we have witnessed a resurgence of surgery for prevention of ischemic stroke. Landmark trials including the North American Symptomatic Carotid Endarterectomy Trial and the European Carotid Surgery Trial have explored the role of carotid endarterectomy in this context, comparing the procedure with best medical treatment in patients with high-grade stenosis of the internal carotid artery and transient ischemic attack or minor nondisabling stroke in the same territory. Here, we discuss the lessons learnt from these trials, and review the Asymptomatic Carotid Atherosclerosis Study and the Asymptomatic Carotid Surgery Trial, which attempted to resolve the rather vexing issue of surgical treatment for patients with asymptomatic internal carotid artery stenosis. We also review the best medical treatment for patients undergoing carotid endarterectomy in the perioperative period, and examine the risk of ischemic stroke after CABG surgery, both when this procedure is performed alongside endarterectomy and when CABG surgery and endarterectomy are performed as a two-staged procedure.

Risk Estimates of Stroke After Coronary Artery Bypass Graft and Carotid Endarterectomy

Neurologic complications of cardiovascular surgeries are well documented in the literature. Neurologic deficits may be mild and reversible or may be associated with permanent neurologic deficit. The incidence and severity of such complications vary according to the type of surgical procedure and usually correlate with patients' preoperative general medical condition, duration of surgeries, and intraoperative complications.

Symptomatic and asymptomatic carotid stenosis: just when we thought we had all the answers

The management of symptomatic and asymptomatic carotid stenosis has been a hotly debated topic for decades. The publication of four randomized controlled trials of carotid endarterectomy has clarified many of the issues. Patients with symptomatic carotid stenosis >70% benefit most with an absolute risk reduction of 17% over 2 years with numbers needed to treat of 3-6, whereas in patients with asymptomatic carotid stenosis >60%, the absolute risk reduction is 1% per annum (numbers needed to treat = 14-17). There is doubt about the benefit in women >70 years of age with asymptomatic stenosis. Carotid angioplasty and stenting is in its infancy and may one day supplant carotid endarterectomy as the treatment of choice; however, currently indications for this procedure include participation in randomized controlled trials, surgically inaccessible stenosis, in patients with combined symptomatic carotid and symptomatic coronary artery disease or in patients with severe co-morbidities that preclude formal carotid endarterectomy.

Neurologic complications of cardiac surgery: Current concepts and recent advances

Neurologic complications following cardiac surgery result in increased morbidity and mortality. The incidence of stroke is 2% to 4%, but is substantially higher in patients with a prior history of stroke. The success of off-pump techniques in altering this risk is controversial. The efficacy and safety of simultaneous carotid endarterectomy and coronary artery bypass surgery are still debated. Mechanical clot retrievers may offer new opportunity to treat postoperative large, middle cerebral artery strokes. The risk of cognitive deficits is debatable but may be due to factors other than the use of bypass and may not differ from similar deficits after noncardiac surgery. Short-term cognitive deficits usually resolve by 1 to 3 months. Long-term risks are not clearly established. Novel approaches may decrease the incidence of neurocognitive dysfunction. Postoperative seizures may result from global or focal cerebral ischemia due to hypoperfusion, particulate or air emboli, or metabolic causes. Newer anticonvulsant drugs may offer additional management opportunities.