Carotid Ultrasound Assessment Prior to Coronary Artery Bypass Grafting - An Irish Cardiac Surgery Center's Experience

BACKGROUND

Carotid stenosis is a risk factor for cerebrovascular accident (CVA) following coronary artery bypass grafting (CABG). Guidelines recommend selective preoperative screening with Doppler ultrasound (US) but nonselective application is commonplace. Recent data has questioned the efficacy of perioperative carotid intervention, challenging the value of this practice. We thus aimed to analyze the utility of carotid US assessment prior to CABG in our institution.

METHODS

This was a retrospective review of all patients over 18 that underwent a nonemergency CABG in a single Irish cardiac surgery center from January 2019 to December 2022.

RESULTS

1161 subjects were included. 1084/1161 (93.36%) underwent US assessment. 41/1084 (3.8%) had ≥70% stenosis and 189/1084 (17.5%) had ≥50% stenosis. 32/1084 (2.95%) underwent confirmatory imaging and 7/1084 (0.64%) underwent carotid intervention. Postoperative CVA occurred in 18/1161 (1.55%) and ≥70% (P = 0.024) and ≥50%(P < 0.001) carotid stenosis were associated with same. Chronic kidney disease (odds ratio [OR] = 1.66,P = 0.01), decreasing hemoglobin (OR = 1.13,P = 0.019), increasing age (OR = 1.03,P = 0.011) and being a current (OR = 3.21,P < 0.001) or ex-smoker (OR = 1.82,P = 0.004) were risk factors for ≥50% carotid stenosis on logistic regression. Multivessel coronary artery disease (CAD) was not associated with carotid stenosis (P = 0.563). Of those that underwent carotid intervention, 0/7 (0%) suffered a CVA, but this protective effect failed to reach statistical significance for those with ≥70% (P = 1) or ≥50% (P = 1) carotid stenosis.

CONCLUSIONS

Carotid US screening altered the management of only a small proportion of CABG patients despite near universal application, challenging the effectiveness of this practice. Multivessel CAD was not associated with carotid stenosis despite European guidelines listing it as screening criteria. Predictive models must be developed using identified risk factors to enable targeted preoperative screening.

One-day, sequential carotid artery stenting followed by cardiac surgery in patients with severe carotid and cardiac disease

Optimal management of patients with internal carotid artery (ICA) stenosis concurrent with severe cardiac disease remains undefined. The aim of this study is to evaluate the safety and feasibility of the one-day, sequential approach by carotid artery stenting (CAS) immediately followed by cardiac surgery. The study included 70 consecutive patients with symptomatic > 50% or ⩾ 80% asymptomatic ICA stenosis coexisting with severe coronary/valve disease, who underwent one-day, sequential CAS + cardiac surgery. The majority of patients (85.7%) had CSS class III or IV angina and 10% had non-ST elevation myocardial infarction. The EuroSCORE II risk was 2.4% (IQR 1.69-3.19%). All CAS procedures were performed according to the 'tailored' algorithm with a substantial use of proximal neuroprotection devices of 44.3%. Closed-cell (75.7%) and mesh-covered (18.6%) stents were implanted in most cases. The majority of patients underwent isolated coronary artery bypass grafting (88.6%) or isolated valve replacement (7.1%). No major adverse cardiac and cerebrovascular events (MACCE) occurred at the CAS stage. There were three (4.3%) perioperative MACCE: one myocardial infarction and two deaths. All MACCE were related to cardiac surgery and were due to the high surgical risk profile of the patients. Up to 30 days, no further MACCE were observed. No perioperative or 30-day neurological complications occurred. In this patient series, one-day, sequential CAS and cardiac surgery was relatively safe and did not result in neurological complications. Thus, a strategy of preoperative CAS could be considered for patients with severe or symptomatic ICA stenosis who require urgent cardiac surgery.

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.

Coronary artery bypass grafting for left main disease and the risk of stroke: Incidence, aetiology and prevention

This review explores the association between left main disease and the increased risk of perioperative stroke following coronary artery bypass grafting, specifically addressing the potential underlying mechanisms and its potential prevention. In particular, this correlation appears stronger for patients with left main disease when compared to patients with isolated triple vessel disease. Even though evidence on this topic is limited and of modest quality, there appears to be a significant association between ascending aorta atherosclerosis and coronary artery disease. Furthermore, there seems to be a relationship between the severity and extent of carotid artery stenosis and coronary artery disease. Carotid artery disease is itself associated with atherosclerosis of the ascending aorta, a well-recognised risk factor for postoperative atheroembolic stroke. The association between left main disease, ascending aorta atherosclerosis and carotid artery stenosis may reflect an increased systemic atherosclerotic burden and hence explain, at least partially, the higher risk of perioperative cerebrovascular events. Potential pre-, intra- and post-operative strategies for stroke prevention are discussed.

Screening for Peripheral Arterial Disease and Carotid Artery Disease in Patients With Abdominal Aortic Aneurysm

Screening for concomitant atherosclerotic disease is important in cardiovascular risk reduction. This study assessed the prevalence of carotid artery disease (CAD) and peripheral arterial disease (PAD) in patients with known abdominal aortic aneurysms (AAAs). All patients with AAA attending the vascular laboratory between the January 1, 2007, and December 31, 2009, were eligible for a carotid ultrasound and measurement of ankle brachial indices. A total of 389 (305 males) patients were identified on the AAA surveillance program with a mean (±standard deviation) age of 76 (±8) years. The mean age of the males was 75.4 (±7.8) years, and the mean age of the females was 77 (±11) years. A total of 332 patients were assessed for CAD, and 101 (30.4%) of those were found to have significant disease. A total of 289 patients were assessed for PAD of which 131 (45.3%) were found to have PAD at rest, and 289 patients were assessed for both and 59 (20.4%) patients had significant CAD + PAD. Patients with AAAs are at high risk of other atherosclerotic disorders, and, therefore, they should receive intensive medical optimization.

Meta-Analysis of Abdominal Aortic Aneurysm in Patients With Coronary Artery Disease

The high coronary artery disease (CAD) prevalence in patients with abdominal aortic aneurysm (AAA) is well known. However, the inverse relation has been little explored. We present, based on a systematic review and meta-analysis of the published evidence, a critical appraisal of the issue of AAA prevalence and also AAA predictive risk factors in patients with CAD, comparing it with AAA prevalence in subjects without CAD. A total of 22 studies involving 13,388 patients with CAD met the inclusion criteria. Overall, AAA prevalence in patients with CAD was 8.4% (95% confidence interval [CI] 6.9 to 10.3), significantly higher than in subjects without CAD (odds ratio [OR] 2.42, 95% CI 2.08 to 2.81). Pooled analysis revealed that smoking, arterial hypertension, and concomitant carotid artery stenosis were significantly associated with AAA in patients with CAD (OR 1.72, 95% CI 1.14 to 2.61; OR 1.57, 95% CI 1.06 to 2.35; OR 2.14, 95% CI 1.20 to 3.79, respectively). In patients with CAD, AAA prevalence tended to be higher with concomitant peripheral artery disease (OR 2.66, 95% CI 0.82 to 8.61, p = 0.08). In conclusion, AAA prevalence was significantly higher in patients with CAD versus subjects without CAD.

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.

Evaluation of the clinical utility of a carotid bruit

BACKGROUND

Uncertainty exists over whether listening for carotid bruits as part of the clinical examination is informative in terms of predicting the presence or severity of carotid stenosis.

AIM

We sought to undertake a comprehensive meta-analysis and meta-regression of all studies to date that have assessed the relationship between a carotid bruit and severity of degree of stenosis.

METHODS

Electronic databases were used to identify all published studies in humans evaluating the association between bruit and stenosis published until and including October 2011. Pooled sensitivity, specificity and diagnostic odds ratio (DOR) were calculated for each stenosis group. Summary receiver operating characteristic (SROC) curve analysis was performed in studies assessing clinically relevant (i.e. >70%) stenosis. Meta-regression was performed in all studies, using random effects.

RESULTS

We identified 26 studies evaluating the association between carotid bruit and stenosis, in 15 117 arteries. For clinically relevant stenosis (i.e. >70%), we found pooled sensitivity 0.53 [95% confidence interval (CI): 0.5-0.55], specificity 0.83 (95% CI: 0.82-0.84) and DOR 4.32 (95% CI: 2.78-6.66). SROC curve analysis gave an area under the curve of 0.73. Meta-regression analysis showed a (non-significant) (P = 0.067) inverse relationship between carotid bruit and stenosis.

CONCLUSION

The carotid bruit is of moderate value for detecting clinically relevant carotid stenosis. It gives high specificity but low sensitivity. The likelihood of a carotid bruit does not increase at increasing degrees of stenosis.

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.

Extracranial Carotid Stenosis and Peripheral Arterial Disease in Thai Patients With Coronary Artery Disease

We assessed the prevalence of carotid stenosis (CS) and peripheral arterial disease (PAD) in patients with coronary artery disease (CAD) to determine the relationship between these conditions in a Thai population. All patients with coronary angiography during June 2008 and August 2009 were studied. Carotid duplex and ankle-brachial index (ABI) were performed. One hundred and seventy-seven patients were studied (95 men, mean age of 65). Carotid stenosis and PAD were diagnosed in 16 patients (9%) and 68 patients (38.4%), respectively. The presence of carotid bruit and older age were independent predictors of CS and PAD, respectively. There was no correlation between the presence of CS/PAD and the extent of coronary artery lesions. Although CS was uncommon in patients with CAD, the patients with cervical bruit should be screened for CS. Prevalence of PAD was high, confirming the presence of diffuse atherosclerosis in many patients with CAD.

Clinical impact of computerised tomographic angiography performed for preoperative evaluation before coronary artery bypass grafting

OBJECTIVE

In our institution, computerised tomographic (CT) angiography has been performed as a near-routine test before coronary artery bypass grafting (CABG) to evaluate the aorta and its branches. We aimed to determine its impact on operative procedure and perioperative management.

METHODS

From January 2006 through December 2008, neck-to-leg systemic arteries were evaluated by 64-slice multidetector CT scan in 284 patients before CABG. For them, medical records and cardiac surgery database were retrospectively reviewed to investigate the incidence of pathologic lesions of the aorta and its major branches, other incidental lesions and procedure- or management-related decision affected by CT angiography.

RESULTS

In 36 patients (12.7%), cannulation and clamping of the ascending aorta were thought too dangerous because of severe atherosclerotic change. The use of cardiopulmonary bypass was inevitable in 10 of them, and postoperative mortality rate was significantly higher (3/10, 30%) than in the remaining patients (2/274, 0.7%). Conduit selection or grafting strategy was changed due to severe left subclavian artery stenosis or leg vein varicosity in 18 patients (6.3%). For the following problems, surgical interventions were performed in 34 patients (12.0%) concomitantly or during the same admission with CABG; > or = 90% stenosis in carotid (5.6%), iliofemoral (11.6%) or renal (4.6%) arteries, aortic aneurysm (14.4%, six of them met surgical indication) and incidental malignant neoplasm (2.8%). Counting all of the above, preoperative CT angiography affected risk assessment, CABG procedure itself, perioperative management or follow-up plan in 142 patients (50%).

CONCLUSIONS

Because preoperative CT angiography considerably affected management in one half of patients, we recommend its use as a routine test before CABG, unless contraindicated.