Patients undergoing cardiac surgery with asymptomatic unilateral carotid stenoses have a low risk of peri-operative stroke

The role of carotid artery stenosis in predicting stroke after coronary artery bypass grafting in a Chinese cohort study

Current guidelines give priority to surgical treatment of carotid artery stenosis (CAS) before coronary artery bypass grafting (CABG), especially in symptomatic patients. Carotid artery stenting is an alternative treatment for narrowing of the carotid arteries. This study sought to demonstrate the role of severe CAS in predicting stroke after CABG and assess the efficacy of carotid artery stenting in preventing postoperative stroke in a Chinese cohort. From 2015 to 2021, 1799 consecutive patients undergoing isolated CABG surgery were retrospectively recruited in a Chinese cohort. The predictive value of severe CAS in postoperative stroke and carotid stenting in preventing postoperative stroke was statistically analyzed. The incidence of postoperative stroke was 1.67%. The incidence of CAS with stenosis ≥ 50% and ≥ 70% was 19.2% and 6.9%. After propensity matching, the incidence of stroke was 8.0% in the severe CAS group and 0% in the non-severe CAS group. We successfully established an optimal predictive nomogram for predicting severe CAS in patients undergoing CABG. Carotid artery stenting was found ineffective in preventing postoperative stroke. The present study provides the incidence of CAS and postoperative stroke in a Chinese cohort, identifies severe CAS as an independent risk factor for postoperative stroke after CABG, constructs a nomogram predicting the incidence of severe CAS, and evaluates the effectiveness of carotid artery stenting in preventing postoperative stroke after CABG.

Same-Day Carotid Artery Stenting and Coronary Artery Bypass Surgery

BACKGROUND

The optimal treatment strategy for patients with severe carotid artery disease undergoing coronary artery bypass grafting is still problematic. The important question is whether it is necessary to treat significant carotid disease in patients who have undergone coronary artery bypass grafting. This study analyzed short- and midterm results after same-day carotid artery stenting and coronary artery bypass grafting.

METHODS

From 2013 to 2020, a total of 69 patients were enrolled in the study. Same-day carotid artery stenting and coronary artery bypass grafting were performed in all patients. The study's primary end points were the evaluation rate of stroke, myocardial infarction, and death within short- and midterm periods after the procedures.

RESULTS

The 30-day mortality was 0%. The occurrences of perioperative adverse events, namely stroke, myocardial infarction, and transient ischemic attack, were 1 (1.4%), 1 (1.4%), and 4 (5.8%), respectively. Mean (IQR) follow-up time was 28 (IQR, 17-43) months. Six (8.8%) patients died during this period. Fatal stroke was registered in 2 cases, and 1 patient experienced a disabling stroke with a fatal outcome. The other 3 patients died because of chronic renal disease, a traffic accident, and for an unknown reason, respectively. Midterm survival in the group was 91.2%.

CONCLUSION

The study showed that same-day carotid artery stenting and coronary artery bypass grafting for concomitant carotid and coronary disease treatment could be a promising and feasible therapeutic strategy.

Effective treatment of severe stenosis of the carotid and coronary arteries: a case study

It is considered acceptable to conservatively manage coronary artery bypass grafting patients with carotid artery disease without the need for preoperative corrective carotid revascularization. However, in the present case, rapidly progressive stroke symptoms with penumbra suggested in the arterial spin labeling, carotid artery stenting was performed successfully.

Relationship Between the Degree of Carotid Stenosis and the Risk of Stroke in Patients Undergoing Cardiac Surgery

BACKGROUND

The impact of carotid stenosis (CS) in patients undergoing cardiac surgery remains controversial. The aim of this study was to evaluate the association between carotid stenosis and stroke and/or transient ischemic attack (TIA) in patients undergoing cardiac surgery on cardiopulmonary bypass.

METHODS

This is a retrospective cohort study including patients undergoing cardiac surgery on cardiopulmonary bypass between January 2006 and March 2018 at the Quebec Heart and Lung Institute. Data of patients' preoperative demographic characteristics, operative and postoperative variables were taken from a computerized database and patients' charts. Univariate and multivariate analyses were performed.

RESULTS

A total of 20,241 patients were included in the study. Among those who had received preoperative carotid ultrasound, 516 (2.6% of the total population) had unilateral or bilateral CS ≥50%. Categorized levels of carotid stenosis severity were identified as independent risk factors for post-operative stroke and/or transient ischemic attack occurrence. There was an almost three-fold increased risk of post-operative neurologic events in 80-99% CS vs. less severe 50-79% CS [OR 2.91; IC95% (1.30-6.54)] suggesting that the degree of severity of CS is potentially a strong independent predictor of post-operative neurologic events.

CONCLUSIONS

CS is an independent risk factor of post-operative stroke and/or TIA. This study suggests for the first time that the risk of stroke increases with the degree of severity of CS, with the greatest risk being for CS between 80-99%. The strength of this relationship and potential causality effect should be further explored in a prospective study focusing on this most at risk population.

Contemporary Management of Patients with Concomitant Coronary and Carotid Artery Disease

The ideal management of concomitant carotid and coronary artery occlusive disease remains elusive. Although researchers have advocated the potential benefits of varying treatment strategies based on either concomitant or staged surgical treatment, there is no consensus in treatment guidelines among national or international clinical societies. Clinical studies show that coronary artery bypass grafting (CABG) with either staged or synchronous carotid endarterectomy (CEA) is associated with a high procedural stroke or death rate. Recent clinical studies have found carotid artery stenting (CAS) prior to CABG can lead to superior treatment outcomes in asymptomatic patients who are deemed high risk of CEA. With emerging data suggesting favorable outcome of CAS compared to CEA in patients with critical coronary artery disease, physicians must consider these diverging therapeutic options when treating patients with concurrent carotid and coronary disease. This review examines the available clinical data on therapeutic strategies in patients with concomitant carotid and coronary artery disease. A treatment paradigm for considering CAS or CEA as well as CABG and percutaneous coronary intervention is discussed.

Carotid endarterectomy for critical stenosis prior to cardiac surgery: Should it be done? A retrospective cohort study

INTRODUCTION

Stroke remains a major cause of morbidity and mortality after cardiac surgery affecting 2% of patients. Extra-cranial carotid artery disease has been implicated in the aetiology of post cardiac surgery stroke. The aim of the study was to evaluate and compare the morbidity and mortality in patients undergoing cardiac surgery with or without staged carotid endarterectomy (CEA) in a tertiary referral centre.

METHODS

A 5 year retrospective study was performed. The primary endpoints were defined as peri-operative stroke and myocardial infarction (MI) with secondary outcome defined as death within 30 days of surgery.

RESULTS

In total 5924 cardiac procedures and 29 staged CEA's were performed. The rate of stroke and MI was significantly higher in patients undergoing staged CEA pre-cardiac surgery compared to patients undergoing cardiac surgery with confirmed or presumed normal carotid arteries (10.34% vs 1.43%; P = .008 and 13.79% vs 0.38%; P < .0001, respectively). There was no significant difference in the stroke and MI rate in those patients undergoing cardiac surgery with confirmed or presumed normal carotid arteries compared to those with significant carotid disease undergoing cardiac surgery with no prior carotid intervention (1.43% vs 3.16%; P > .05 and 0.38% vs 1.05%; P > .05, respectively).

CONCLUSIONS

Carotid disease is associated with an increased risk of stroke post cardiac surgery. Staged carotid intervention cannot be justified based on these results. Increased risk of stroke post cardiac surgery in patients with significant carotid disease needs to be accepted, as the risk of stroke and MI during carotid intervention pre cardiac surgery is significantly higher.

Stroke associated with coronary artery bypass grafting

While coronary artery bypass grafting (CABG) has been playing a significant role in the revascularization for ischemic heart disease, neurological complications associated with CABG have been a primary concern. Stroke, although the incidence is low, is one of the most devastating complication of CABG. Many studies have identified the risk factors for stroke with CABG, such as prior stroke, carotid artery stenosis, aortic atherosclerosis, atrial fibrillation and cardiopulmonary bypass. Various rational approaches focusing on individual risk factor have been proposed for the stroke. Prophylactic carotid revascularization is an important strategy, and the diagnosis of carotid stenosis has to be established correctly. Prevention of emboli from aortic plaque is also an essential issue. Intraoperative monitoring with transesophageal or epiaortic ultrasound is useful to identify mobile atheromatous plaques and to select appropriate aortic manipulations. Maintenance of cerebral blood flow and blood pressure during cardiopulmonary bypass might be critical issues. Besides, there are conflicting two opinions regarding off-pump CABG; one supports an efficiency for the prevention of stroke while the other advocates no effect. This discrepancy might be explained by the difference of the risk of stroke in the population of the individual study and by the variation of the percentage of aortic clamping or aortic anastomosis in each study. Pharmaceutical therapies such as statin, preventive medication for atrial fibrillation, or antiplatelet are promising methods. Although it is hard to decrease the incidence of the stroke with any single countermeasure, sustained effort should be continued to overcome the stroke associated with CABG.

Cerebral lesions in patients undergoing coronary artery bypass grafting in relation to asymptomatic carotid and vertebral artery stenosis

OBJECTIVES

Carotid artery stenosis (CAS) and vertebral artery stenosis (VAS) are associated with cerebral infarction after coronary artery bypass graft surgery (CABG). It remains unclear whether this association is causal. We investigated the associations between neurologically asymptomatic CAS and VAS and the occurrence of subclinical cerebral lesions after CABG verified by magnetic resonance imaging.

METHODS

CABG patients were included and CAS and VAS were identified by magnetic resonance angiography. Cerebral magnetic resonance imaging was performed to identify new post-operative subclinical cerebral lesions. The associations between CAS/VAS post-operative cerebral lesions were investigated.

RESULTS

Forty-six patients were included in the study. 13% had significant CAS and 11% had significant VAS. Thirty-five percent had new cerebral infarction postoperatively. We found a significant association between the presence of cerebral vessel stenosis and acute cerebral infarction (67% vs. 27%, p = 0.047). However none of the patients with stenosis had isolated cerebral lesions in the ipsilateral vascular territory.

CONCLUSION

Asymptomatic CAS and VAS is common in CABG patients and is associated with an increased risk of postoperative cerebral infarction. Our study suggests that asymptomatic CAS and VAS primarily are risk markers rather than causal factors for cerebral infarction after CABG.

Does preoperative carotid stenosis screening reduce perioperative stroke in patients undergoing coronary artery bypass grafting?

A number of institutions routinely perform carotid artery ultrasound screening before coronary artery bypass grafting (CABG) to identify carotid artery disease requiring revascularization before or during CABG, with the expectation of reducing perioperative neurologic events. The assumptions are that carotid disease is causally related to perioperative stroke and that prophylactic carotid revascularization decreases the risk of post-CABG neurologic events. Although carotid artery stenosis is a known risk factor for perioperative stroke in patients undergoing CABG, it might be a surrogate marker for diffuse atherosclerotic disease rather than a direct etiologic factor. Moreover, the benefit of prophylactic carotid revascularization in patients with asymptomatic unilateral carotid disease is uncertain. Therefore, we have reviewed the literature for evidence that preoperative carotid artery screening, by identifying patients with significant carotid artery stenosis and altering their management, reduces perioperative neurologic events in those undergoing CABG.

Simultaneous coronary artery bypass grafting and carotid endarterectomy can be performed with low mortality rates

Introduction

There is controversy over the best approach for patients with concomitant carotid and coronary artery disease. In this study, we report on our experience with simultaneous carotid endarterectomy (CEA) and coronary artery bypass graft (CABG) surgery in our clinic in the light of data in the literature.

Methods

Between January 1996 and January 2009, a total of 110 patients (86 males, 24 females; mean age 65.11 ± 7.81 years; range 44–85 years), who were admitted to the cardiovascular surgery clinic at our hospital, were retrospectively analysed. All patients underwent simultaneous CEA and CABG. Demographic characteristics of the patients and a history of previous myocardial infarction (MI), hypertension, diabetes mellitus, hyperlipidaemia, peripheral arterial disease and smoking were recorded.

Results

One patient (0.9%) with major stroke died due to ventricular fibrillation. Peri-operative neurological complications were observed in seven patients (6%). Complications were persistent in two patients. Four patients (3%) had postoperative major stroke, whereas three patients (2%) had transient hemiparesis. No peri-operative myocardial infarction was observed.

Conclusion

Simultaneous CEA and CABG can be performed with low rates of mortality and morbidity.

Should patients with asymptomatic significant carotid stenosis undergo simultaneous carotid and cardiac surgery?

A best evidence topic in cardiovascular surgery was written according to a structured protocol. The question addressed was whether patients with severe asymptomatic carotid and coronary artery diseases should undergo simultaneous carotid endarterectomy (CEA) and coronary artery bypass grafting (CABG). A total of 624 papers were found using the reported search, of which 20 represent the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study results of these papers are tabulated. Previous cohort studies showed mixed results, while advocating for the necessity of a randomized controlled trial (RCT). A recent RCT showed that patients undergoing prophylactic or simultaneous CEA + CABG had lower rates of stroke (0%) compared with delayed CEA 1-3 months after CABG (7.7%), without significant perioperative mortality difference. This study included patients with unilateral severe (>70%) asymptomatic carotid stenosis requiring CABG. An earlier partly randomized trial also showed better outcomes for patients undergoing simultaneous procedures (P = 0.045). Interestingly, systematic reviews previously failed to show compelling evidence supporting prophylactic CEA. This could be partly due to the fact that these reviews collectively analyse different cohort qualities. Neurological studies have, however, shown reduced cognitive and phonetic quality and function in patients with unilateral and bilateral asymptomatic carotid artery stenosis. Twenty-one RCTs comparing lone carotid artery stenting (CAS) and CEA informed the American Heart Association guidelines, which declared CAS comparable with CEA for symptomatic and asymptomatic carotid stenosis (CS). However, the risk of death/stroke for CAS alone is double that for CEA alone in the acute phase following onset of symptoms, while CEA alone is associated with a doubled risk of myocardial infarction. There is, however, no significant difference for combined 30-day risk of death/stroke/myocardial infarction. Outcomes of hybrid or simultaneous CAS/CABG procedures show comparable results, albeit from rather small cohorts. While current evidence leans towards simultaneous CEA/CABG, the emergence of hybrid operating theatres in various institutions may allow larger cohorts with subsequent significant data on simultaneous CAS/CABG. A randomized controlled trial comparing both approaches would be crucial in informing future updates of existing guidelines.

Silent coronary artery disease in Japanese patients undergoing carotid artery stenting

BACKGROUND

The aim of this retrospective study was to determine the prevalence of silent coronary artery disease (CAD) and the risk factors associated with concomitant CAD in Japanese patients undergoing carotid artery stenting (CAS).

METHODS

The records of 112 consecutive patients (99 men and 13 women; mean age 70 ± 8 years) who underwent elective CAS at our institution for extracranial carotid artery stenosis between January 2006 and January 2011 were reviewed retrospectively. During this period, preoperative CAD screening by coronary angiography was performed in all patients. Patients were diagnosed with CAD when ≥ 1 coronary arteries had stenosis ≥ 75% and were classified into 2 groups: (1) a group with CAD that was based on preoperative coronary angiography or a history of percutaneous coronary intervention (PCI) and/or coronary artery bypass grafting (CABG), and (2) a group without CAD that had no angiographically documented stenosis ≥ 75%.

RESULTS

Sixteen (14.3%) patients had CAD that had already been treated by PCI and/or CABG. Silent CAD was detected in 39 (34.8%) of 112 patients. Taken together, 55 (49.1%) patients had clinically significant CAD. The patients with CAD were more likely to have diabetes mellitus (DM; P = .001), dyslipidemia (P = .013), and bilateral carotid disease (P = .033). Multivariate analysis revealed that DM (odds ratio 3.07; 95% confidence interval 1.25-7.53) and bilateral carotid stenosis (odds ratio 2.72; 95% confidence interval 1.10-6.75) were independent variables associated with concomitant CAD.

CONCLUSIONS

Perioperative CAD screening revealed that silent CAD was frequently diagnosed in Japanese patients scheduled for CAS, particularly in those with DM and/or bilateral carotid stenosis.

Advances in the management of carotid artery disease: focus on recent evidence and guidelines

Recent landmark randomized trials and society guidelines have significantly revised the management of carotid artery disease. Duplex ultrasonography is the recommended initial diagnostic test for the assessment of extracranial carotid artery stenosis. Carotid artery imaging is reasonable in select patients scheduled for coronary artery bypass graft (CABG) surgery. Carotid revascularization can be achieved safely and effectively with carotid endarterectomy or carotid artery stenting. Because each procedure has a different risk/benefit profile, the optimal approach is to match the particular patient to the intervention that maximizes outcome benefit. Carotid revascularization is recommended in patients scheduled for CABG surgery when the carotid artery stenosis is symptomatic and/or bilateral. Further trials are required to guide the management of asymptomatic unilateral carotid artery stenosis in patients undergoing CABG surgery. Aggressive medical therapy remains the gold standard for intracranial carotid artery disease because landmark trials have shown no outcome improvement with vascular bypass or percutaneous angioplasty and stenting. A large recent trial showed that local anesthesia, as compared with general anesthesia, for carotid endarterectomy has no major clinical outcome advantage. Although carotid artery stenting is associated with a reduced risk of myocardial ischemia, it still has important risks of stroke and hemodynamic instability that significantly affect clinical outcome. The timing and choice of carotid revascularization technique ultimately depends on multiple clinical factors.

Importance of strict patient selection criteria for combined carotid endarterectomy and coronary artery bypass grafting

BACKGROUND

Management of patients with severe concomitant carotid and coronary disease remains controversial. We report our experience of combined carotid endarterectomy (CEA) and coronary artery bypass surgery (CABG) over a fifteen year period using strict patient selection criteria.

METHODS

From 1st January 1995 to December 31st 2009 165 patients underwent combined CABG/CEA procedures at the Mater Hospital. Mean age was 68.2 years (range 43-88) and 127 (77%) were male. Fifty-three (32%) had symptomatic carotid disease. Indications for combined procedures were the presence of symptomatic >70% or asymptomatic >80% internal carotid artery stenosis in a patient requiring urgent CABG because of either unstable angina, recent MI, severe triple vessel disease or severe Left Anterior Descending or Left Main Stem stenosis.

RESULTS

Thirty-day stroke and death rate was 3%. All neurological events were in the hemisphere contralateral to the carotid surgery and symptoms had completely resolved prior to discharge from hospital. One patient required evacuation of a cervical haematoma and there were two transient XII nerve palsies.

CONCLUSION

Combined CEA/CABG can be performed safely with acceptable morbidity and mortality in patients selected in accordance with strict criteria in a centre with a large experience of both cardiac and carotid surgery.

Interaction of cerebrovascular disease and contralateral carotid occlusion in prediction of shunt insertion during carotid endarterectomy

INTRODUCTION

To assess the possible role and the interaction of cerebrovascular disease and vascular stenosis on the necessity of shunt insertion during carotid endarterectomy (CEA).

MATERIAL AND METHODS

Eighty consecutive patients undergoing CEA under regional anaesthesia were prospectively enrolled. Patients were divided into two groups depending on whether they were shunted or not. The measured end-points were co-morbidities degree of contralateral and carotid stenosis and other intra- and postoperative outstanding parameters. ANOVA, Student's t and χ(2) tests were used (p<0.05). Variables differing significantly between groups and potential confounders were used in backward stepwise logistic regression to estimate the relative risk (RR, 95% CI) of shunt. In addition Wald's test (p<0.05) with and without adjustments for potential confounders was used with various different multivariate analysis models.

RESULTS

Contralateral stenosis and cerebral vascular accidents (CVA) were more frequently observed in shunted patients. The RR for patients with contralateral stenosis ≥ 50% was 1.3 (95% CI 1.0-1.5) and for patients with previous CVA was 1.2 (95% CI 1.0-1.4). For contralateral stenosis and CVA together the RR increased to 7.7 (95% CI 1.0-14.4). A model based on contralateral stenosis and CVA was found to be statistically significant (p=0.003) for shunt (RR=1.1, 95% CI 1.0-2.1). Relative excess risk due to interaction of both factors was 6.2.

CONCLUSIONS

The findings suggest that patients with contralateral stenosis ≥ 50% and previous CVA have a higher risk of requiring shunt use during CEA than patients with these risk factors separately.

Regional use of combined carotid endarterectomy/coronary artery bypass graft and the effect of patient risk

INTRODUCTION

Although carotid artery stenosis and coronary artery disease often coexist, many debate which patients are best served by combined concurrent revascularization (carotid endarterectomy [CEA]/coronary artery bypass graft [CABG]). We studied the use of CEA/CABG in New England and compared indications and outcomes, including stratification by risk, symptoms, and performing center.

METHODS

Using data from the Vascular Study Group of New England from 2003 to 2009, we studied all patients who underwent combined CEA/CABG across six centers in New England. Our main outcome measure was in-hospital stroke or death. We compared outcomes between all patients undergoing combined CEA/CABG to a baseline CEA risk group comprised of patients undergoing isolated CEA at non-CEA/CABG centers. Further, we compared in-hospital stroke and death rates between high and low neurologic risk patients, defining high neurologic risk patients as those who had at least one of the following clinical or anatomic features: (1) symptomatic carotid disease, (2) bilateral carotid stenosis >70%, (3) ipsilateral stenosis >70% and contralateral occlusion, or (4) ipsilateral or bilateral occlusion.

RESULTS

Overall, compared to patients undergoing isolated CEA at non-CEA/CABG centers (n = 1563), patients undergoing CEA/CABG (n = 109) were more likely to have diabetes (44% vs 29%; P = .001), creatinine >1.8 mg/dL (11% vs 5%; P = .007), and congestive heart failure (23% vs 10%; P < .001). Patients undergoing CEA/CABG were also more likely to take preoperative beta-blockers (94% vs 75%; P < .001) and less likely to take preoperative clopidogrel (7% vs 25%; P < .001). Patients undergoing CEA/CABG had higher rates of contralateral carotid occlusion (13% vs 5%; P = .001) and were more likely to undergo an urgent/emergent procedure (30% vs 15%; P < .001). The risk of complications was higher in CEA/CABG compared to isolated CEA, including increased risk of stroke (5.5% vs 1.2%; P < .001), death (5.5% vs 0.3%; P < .001), and return to the operating room for any reason (7.6% vs 1.2%; P < .001). Of 109 patients undergoing CEA/CABG, 61 (56%) were low neurologic risk and 48 (44%) were high neurologic risk but showed no demonstrable difference in stroke (4.9% vs 6.3%; P = .76), death, (4.9 vs 6.3%; P = .76), or return to the operating room (10.2% vs 4.3%; P = .25).

CONCLUSIONS

Although practice patterns in the use of CEA/CABG vary across our region, the risk of complications with CEA/CABG remains significantly higher than in isolated CEA. Future work to improve patient selection in CEA/CABG is needed to improve perioperative results with combined coronary and carotid revascularization.

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.

Is carotid artery disease responsible for perioperative strokes after coronary artery bypass surgery?

The coronary and extracranial carotid vascular beds are often simultaneously affected by significant atherosclerotic disease, and stroke is one of the potential major complications of coronary artery surgery. As a result, there is no shortage of reports in the vascular surgery literature describing simultaneous coronary and carotid artery revascularizations. Generally, these reports have found this combination of operations safe, but have stopped short of proving that it is necessary. Intuitively, simultaneous carotid endarterectomy and coronary artery bypass surgery could be justified if most perioperative strokes were the result of a significant carotid stenosis, either directly or indirectly. At first glance this appears to be a fairly straightforward issue; however, much of the evidence on both sides of the argument is circumstantial. One significant problem in analyzing outcome by choice of treatment in patients presenting with both coronary and carotid disease is the multiple potential causes of stroke in coronary bypass patients, which include hemorrhage and atheroemboli from aortic atheromas during clamping. But this controversial subject is now open to discussion, and our debaters have been given the challenge to clarify the evidence to justify their claims.

Asymptomatic carotid disease and cardiac surgery consensus

The Carotid Disease and Cardiac Surgery Consensus Meeting was convened as a multidisciplinary gathering to consider the management of patients undergoing cardiac surgery who are found to have asymptomatic carotid artery disease. There are no randomized trials concerning whether carotid interventions are of value in this situation and the natural history is unclear. Bilateral carotid artery disease (≥70% stenosis) should be regarded clinically relevant when considering hemodynamic and short-term surgical stroke risk. However, this may be because the presence of significant carotid disease is also a marker for aortic arch and intracerebral disease. A natural history study is urgently needed to determine the incidence, predictive factors, and natural history of asymptomatic carotid disease in patients undergoing contemporary cardiac surgical interventions to inform the design of any future randomized trial.

Update on surgical management for asymptomatic carotid stenosis

The management of asymptomatic carotid stenosis has been a topic of considerable debate. In this article, we aim to critically review the recent literature as it pertains to surgical management of asymptomatic carotid stenosis. We will explore the most recent trials looking at advancements in best medical therapy, as well as trials that compare traditional carotid endarterectomy to carotid stenting. In addition, we will review the current literature on surgical technique and perioperative risk management. Overall, our current recommendation is for surgical management of asymptomatic carotid disease for stenoses ≥ 80% in patients who are of reasonable perioperative risk.

Synchronous cardiac and carotid revascularisation: the devil is in the detail

BACKGROUND

Studies reporting outcomes following staged/synchronous carotid revascularisation prior to cardiac surgery have generally concluded that procedural strokes are reduced. However, virtually none have commented specifically on the risk of stroke in patients with bilateral carotid disease who then undergo their cardiac procedure in the presence of an unoperated, contralateral stenosis. If carotid disease really was an important cause of peri-operative stroke, these patients should incur a much higher risk of stroke following their cardiac procedure.

METHODS

Retrospective audit of prospectively acquired data in 132 consecutive patients undergoing synchronous carotid endarterectomy and cardiac surgery.

RESULTS

Overall 30-day rates of mortality, ipsilateral stroke and any stroke were 5.3%, 1.5% and 3% respectively. The 30-day rate of death/stroke was 6.8%. In 51 patients with a prior history of stroke/TIA, the 30-day rate of death/stroke was 5.9%, compared with 7.4% in neurologically asymptomatic patients. The majority (57%) had significant bilateral disease and underwent their combined procedure in the presence of a significant, non-operated (asymptomatic) contralateral stenosis (50-99% = 75, 60-99% = 54, 70-99% = 32). Only one patient (90-99% stenosis) suffered a post-operative stroke in the hemisphere ipsilateral to the non-operated, contralateral stenosis.

CONCLUSIONS

Patients undergoing synchronous procedures incurred a low rate of procedural stroke, perhaps justifying this management approach. However, an alternative and more critical analysis suggested that the risk of procedural stroke in patients with significant (non-operated) contralateral asymptomatic carotid disease was extremely low. This challenges the assumption that asymptomatic carotid disease is an important cause of stroke during cardiac surgery.

Known knowns, known unknowns and unknown unknowns: a 2010 update on carotid artery disease

The management of carotid artery disease never ceases to attract controversy. The last 12 months has seen publication of a number of important studies which have informed debate and 2010 holds the prospect of much more. This update offers a personal review of a number of contemporary issues including; (i) guidelines for non-invasive imaging in rapid access clinics, (ii) whether improvements in best medical therapy have rendered many of the conclusions from ACAS and ACST obsolete, (iii) is carotid disease really just a marker for increased stroke risk following cardiac surgery (rather than being an important cause), (iv) what is the current status of endarterectomy and stenting in patients with symptomatic carotid disease and (v) why we must offer expedited interventions to TIA/minor stroke patients. The available evidence suggests that while most 'known knowns' will endure, quite a few may be returning to the category of 'known unknowns' once again. Who knows what 'unknown unknowns' await us in 2010 and beyond.