Increased Risk Associated With Combined Carotid Endarterectomy and Coronary Artery Bypass Graft Surgery: A Propensity-Matched Comparison With Isolated Coronary Artery Bypass Graft Surgery

Effect of untreated carotid artery stenosis at the time of isolated coronary artery bypass grafting

Background

Severe carotid artery stenosis (sCAS) is frequently discovered at the time of evaluation for coronary arterial revascularization. However, there has been controversy regarding the optimal management of sCAS. This study evaluated the potential effects of untreated sCAS at time of coronary artery bypass grafting (CABG) in contemporary practice.

Methods

This was a retrospective study from a multihospital healthcare system including patients undergoing isolated CABG between 2011 and 2018. Patients were stratified by the presence of sCAS (≥80% stenosis) in at least 1 carotid artery. Perioperative and 5-year stroke were compared, and multivariable analysis was used to identify risk-adjusted predictors of stroke and mortality.

Results

A total of 5475 patients were included, 459 (8.4%) with sCAS and 5016 (91.6%) without sCAS. Patients with sCAS experienced more frequent perioperative stroke (4.4% vs 1.2%; P < .001), with most attributable to ischemic or embolic etiologies. The median duration of follow-up was 4.6 years (interquartile range, 3.0-6.5 years). One-year and 5-year survival were both lower in patients with sCAS (P < .001). In multivariable analysis, sCAS was associated with increased risk-adjusted hazard for both mortality (hazard ratio [HR], 1.28; 95% confidence interval [CI], 1.02-1.60; P = .030) and stroke (HR, 1.76; 95% CI, 1.20-2.59; P = .004). The strongest risk-adjusted predictor for stroke was a previous history of stroke (HR, 2.51; 95% CI, 1.77-3.55; P < .001).

Conclusions

This contemporary analysis of CABG procedures reveals that concurrent sCAS continues to confer a significant stroke risk, especially in those with history of previous stroke. Although whether sCAS lesions are responsible for most strokes is unclear, they likely serve as a surrogate for other stroke risk factors.

Prevalence of carotid artery stenosis in neurologically asymptomatic patients undergoing coronary artery bypass grafting for coronary artery disease: Role of anesthesiologist in preoperative assessment and intraoperative management

Objective(s):

This study aimed to determine the prevalence of carotid artery stenosis (CAS) due to atherosclerosis in neurologically asymptomatic patients undergoing coronary artery bypass grafting (CABG) for coronary artery disease (CAD). It contemplated a greater role for the cardiac anesthesiologist in the perioperative management of such patients with either previously undiagnosed carotid artery disease or towards re-assessment of severity of CAS.

Design:

Prospective, observational clinical study.

Setting:

Operation room of a cardiac surgery centre of a tertiary teaching hospital.

Participants:

A hundred adult patients with New York Heart Association (NYHA) classification I to III presenting electively for CABG.

Interventions:

All patients included in this study were subjected to ultrasonic examination by means of acarotid doppler scan to access for presence of CAS just prior to induction of general anesthesia.

Measurements and Main Results:

Based on parameters measured using carotid doppler, the presence of CAS was defined using standard criteria. The prevalence of CAS was found to be as high as 38% amongst the patients included in our study. The risk factors for CAS were identified to be advanced age, history of smoking, diabetes mellitus, dyslipidaemia and presence of a carotid bruit.

Conclusion:

This study points towards the relatively wide prevalence of carotid artery disease in neurologically asymptomatic patients undergoing CABG for CAD in the elective setting. It highlights the need to routinely incorporate carotid ultrasonography in the armamentarium of the cardiac anesthesiologist as standard of care for all patients presenting for CABG.

Management of extracranial carotid artery disease

Stroke is the third leading cause of death in developed nations. Up to 88% of strokes are ischemic in nature. Extracranial carotid artery atherosclerotic disease is the third leading cause of ischemic stroke in the general population and the second most common nontraumatic cause among adults younger than 45 years. This article provides comprehensive, evidence-based recommendations for the management of extracranial atherosclerotic disease, including imaging for screening and diagnosis, medical management, and interventional management.

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.

Randomized comparison of synchronous CABG and carotid endarterectomy vs. isolated CABG in patients with asymptomatic carotid stenosis: the CABACS trial

RATIONALE

High-grade carotid artery stenosis is present in 6-8% of patients undergoing coronary artery bypass graft surgery. Many cardiovascular surgeons advocate staged or synchronous carotid endarterectomy to reduce the high perioperative and long-term risk of stroke associated with multivessel disease. However, no randomized trial has assessed whether a combined synchronous or staged carotid endarterectomy confers any benefit compared with isolated coronary artery bypass grafting in these patients.

AIMS

The objective of this study is to compare the safety and efficacy of isolated coronary artery bypass grafting vs. synchronous coronary artery bypass grafting and carotid endarterectomy in patients with asymptomatic high-grade carotid artery stenosis.

DESIGN

Coronary Artery Bypass graft surgery in patients with Asymptomatic Carotid Stenosis (CABACS) is a randomized, controlled, open, multicenter, group sequential trial with two parallel arms and outcome adjudication by blinded observers. Patients with asymptomatic high-grade carotid stenosis scheduled for elective coronary artery bypass grafting will be assigned to either isolated coronary artery bypass grafting or synchronous coronary artery bypass grafting and carotid endarterectomy by 1 : 1 block-stratified randomization with three different stratification factors (age, gender, modified Rankin scale).

STUDY

The trial started in December 2010 aiming at recruiting 1160 patients in 25 to 30 German cardiovascular centers. The composite primary efficacy end point is the number of strokes and deaths from any cause (whatever occurs first) within 30 days after operation. A 4·5% absolute difference (4% compared to 8·5%) in the 30-day rate of the above end points can be detected with >80% power.

OUTCOMES

The results of this trial are expected to provide a basis for defining an evidence-based standard and will have a wide impact on managing this disease.

Combined Carotid Endarterectomy and Coronary Artery Bypass Grafting Versus Coronary Artery Bypass Grafting Alone: A Retrospective Review of Outcomes at Our Institution

Background: It remains controversial whether patients with concomitant carotid and coronary disease should undergo operative repair separately or in combination. Methods: Patients with documented cerebrovascular disease undergoing coronary artery bypass grafting (CABG) alone were matched by propensity scoring with patients undergoing combined carotid endarterectomy (CEA)/CABG procedures and compared for the occurrence of stroke, myocardial infarction (MI), and mortality. Results: Of the 4943 patients undergoing CABG, 908 had known cerebrovascular disease. Among these, 134 underwent concomitant CEA, and these were propensity matched with 134 patients undergoing CABG only. No differences were observed in the perioperative risks of stroke (4% vs 3%, odds ratio [OR] 1.5, 95% confidence interval [CI] 0.4-5.5), MI (0.7% vs 0.7%, not significant [NS]), or combined cardiovascular events (6% vs 10%, OR 0.5, 95% CI [0.2-1.3]), although mortality (1% vs 8%, OR 0.2, 95% CI [0.04-0.8] was higher with CABG only. Discussion: Addition of CEA to CABG did not significantly alter the risk of perioperative stroke relative to propensity-matched patients undergoing CABG alone.

Biomarkers of asymptomatic carotid stenosis in patients undergoing coronary artery bypass grafting

BACKGROUND AND PURPOSE

Carotid artery stenosis is an important etiologic factor of stroke related to coronary artery bypass surgery. We evaluated clinical and laboratory factors to identify biomarkers for pre-existing carotid artery stenosis in patients undergoing coronary artery bypass surgery.

METHODS

Between June 2006 and September 2008, 811 patients aged ≥50 years underwent preoperative carotid artery duplex scanning as part of a preoperative assessment for nonemergency cardiac procedures. Of these, 54 patients with previous stroke or transient ischemic attack were excluded. The association between various biomarkers and carotid artery stenosis was analyzed by multiple logistic regression analysis. The receiver operating characteristic curves were generated and analyzed to compare diagnostic performance and optimum diagnostic cutoff levels of biomarkers.

RESULTS

A total of 757 patients was included in the study. The prevalence of asymptomatic carotid stenosis of ≥50% and ≥70% was 26.4% and 8.6%, respectively. In multivariate analysis, plasma levels of apolipoprotein B (apoB):apoA-I, lipoprotein(a), and homocysteine were independently associated with carotid stenosis of ≥50%: the OR (95% CI) for apoB/apoA-I, lipoprotein(a), and homocysteine in the highest versus lowest quartile was 2.07 (1.18 to 3.66), 2.17 (1.16 to 4.05), and 2.13 (1.20 to 3.79), respectively. Receiver operating characteristic curve analysis indicated area under the curve values of 0.708 (apoB:apoA-I), 0.678 (lipoprotein[a]), and 0.689 (homocysteine). The sensitivity, specificity, positive and negative predictive values (%) for diagnosis of carotid stenosis ≥50% were 80.0, 50.4, 38.0, and 86.9 for apoB:apoA-I; 47.0, 78.9, 46.1, and 79.5 for lipoprotein(a); and 69.3, 62.1, 41.2, and 84.1 for homocysteine, respectively.

CONCLUSIONS

Our findings indicated that plasma levels of apoB/apoA-I, lipoprotein(a), and homocysteine can predict asymptomatic carotid stenosis in patients undergoing coronary artery bypass surgery.

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.

Treatment strategy for combined carotid artery stenosis and coronary artery disease: staged or simultaneous surgical procedure?

Patients with combined carotid and coronary arterial diseases pose a high risk of cerebrovascular events, and the treatment of choice with either a simultaneous or a staged surgical procedure remains controversial. The literature of combined carotid and coronary arterial diseases of a recent decade in English was retrieved. Totally 41,901 patients undergoing simultaneous or staged carotid and coronary procedures from 53 reports were included. As a result, carotid endarterectomy plus coronary artery bypass remained the most commonly used procedure for the intervention of combined carotid artery stenosis and coronary artery disease, and was associated with higher incidences of perioperative transient ischemic attack, stroke and hospital mortality, but with less perioperative myocardial infarction comparing with the staged procedures. Patients with a simultaneous carotid endarterectomy and coronary artery bypass were generally related more to an advanced atherosclerotic coronary artery disease, so that a pure comparison between the two strategies was not always possible. To compare the efficacy of different surgical methods for combined carotid and coronary arterial diseases is of pronounced importance. The new hybrid approach consisting of the simultaneous carotid artery stenting and subsequent on-pump coronary artery bypass can be a safe approach, with the aim to reduce the surgical trauma as compared to surgical procedures, and to reduce the risk of myocardial infarction in the interval period required for the staged operations. Thus, for patients with combined carotid artery stenosis and coronary artery disease, the simultaneous surgical procedure, rather than the staged procedure, is recommended.

Routine use of nasogastric tubes does not reduce postoperative nausea and vomiting

Routine use of a nasogastric (NG) tube has been suggested to prevent postoperative nausea and vomiting (PONV) despite conflicting data. Accordingly, we tested the hypothesis that routine use of a NG tube does not reduce PONV. Our work is based on data from a large trial of 4055 patients initially designed to quantify the effectiveness of combinations of antiemetic treatments for the prevention of PONV. This analysis uses propensity scores for case matching to ensure group comparability on baseline factors. Intraoperative NG tube use patients and perioperative NG tube use patients were respectively matched to nonuse patients on all available potential confounders. Matched-pairs were identified using propensity scores for 1032 patients with or without intraoperative NG tube use and 176 patients with or without perioperative NG tube use. The incidences of PONV in the intraoperative group were 44.4% vs 41.5% (P = 0.35) with and without tube use, respectively, and 27.8% vs 31.3% (P = 0.61) in the perioperative group. Our results provide evidence that routine use of a NG tube does not reduce the incidence of PONV.

Correlates of carotid stenosis in patients undergoing coronary artery bypass grafting – a case control study

Abstract

Carotid duplex ultrasonography (DUS) is routinely performed prior to coronary artery bypass graft surgery (CABG) on all patients > 65 years old because of the reported associated risk of finding concomitant carotid artery stenosis. Identifying risk factors that correlate with severe carotid stenosis may result in more cost-effective screening for patients with asymptomatic carotid artery disease prior to CABG. We performed a retrospective study to identify risk factors for significant carotid artery disease in patients scheduled to undergo CABG between March 2005 and March 2008 at the Massachusetts General Hospital. Patients with carotid stenosis ≥ 70% identified by DUS ( n = 50) were matched by age and sex to control patients who had < 50% stenosis ( n = 50). Data were analyzed using the chi-squared test or analysis of variance as appropriate. Logistic regression was used to examine multivariate correlates of carotid stenosis. A total of 643 patients were screened to arrive at the patient cohorts described below. This produced a prevalence of 7.7% for significant (> 70%) carotid disease. The patient cohorts were predominantly male with no significant difference in the incidence of diabetes, hypertension, extent of coronary artery disease (CAD) (i.e. left main coronary artery disease (LMCA) and one, two-, or three-vessel CAD) or lipid abnormalities in the two groups. Univariate analysis identified the presence of peripheral arterial disease (PAD, p = 0.001), a cervical bruit ( p < 0.0001), a prior neurological event ( p = 0.020), and the presence of an abdominal aortic aneurysm (AAA; p = 0.046) as significant predictors of ≥ 70% internal carotid artery stenosis. Logistic regression analysis revealed that the presence of a carotid bruit ( p = 0.0068) and PAD ( p = 0.0194) were associated with an increased risk of significant carotid artery disease. In conclusion, the presence of a carotid bruit or PAD predicts an increased likelihood of significant carotid artery disease in patients undergoing CABG. Unlike previous studies, LMCA or extent of CAD did not correlate with significant carotid artery disease. Using these predictive models, a prospective outcomes trial is required to validate these criteria.

Cerebral hemodynamics during coronary artery bypass graft surgery: the effect of carotid stenosis

Carotid stenosis is a frequent coexisting condition in patients undergoing coronary artery bypass graft (CABG) surgery. The impact of carotid stenosis on cerebral perfusion is not fully understood. The purpose of this study was to determine the impact of carotid stenosis on cerebral blood flow velocity in patients undergoing CABG. Seventy-three patients undergoing CABG were prospectively recruited and underwent preoperative Duplex carotid ultrasound to evaluate the degree of carotid stenosis. Intraoperatively, transcranial Doppler ultrasound was used to record the mean flow velocity (MFV) within the bilateral middle cerebral arteries. In addition, during the period of cardiopulmonary bypass, regulators of cerebral hemodynamics such as hematocrit, partial pressure of carbon dioxide and temperature were recorded. The ipsilateral middle cerebral artery mean flow velocity was compared in arteries with and without carotid stenosis using a repeated measures analysis. Seventy-three patients underwent intraoperative monitoring during CABG and 30% (n=22) had carotid stenosis. Overall, MFV rose throughout the duration of CABG including when the patient was on cardiopulmonary bypass. However, there was no significant MFV difference between those arteries with and without stenosis (F=1.2, p=.21). Further analysis during cardiopulmonary bypass, demonstrated that hemodilution and partial pressure of carbon dioxide may play a role in cerebral autoregulation during CABG. Carotid stenosis did not impact mean cerebral blood flow velocity during CABG. The cerebrovascular regulatory process appears to be largely intact during CABG.