Coronary artery bypass grafting (CABG) is one of the

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1 Carotid and Aortic Screening for Coronary Artery Bypass Grafting Ikuo Fukuda, MD, PhD, Seigo Gomi, MD, Ko Watanabe, MD, and Jun Seita, MD Department of Cardiovascular Surgery, Tsukuba Medical Center Hospital, Ibaraki, Japan Background. To identify risk factors for preexisting carotid and aortic disease in coronary artery bypass grafting (CABG), preoperative parameters were analyzed. Methods. Three-hundred eight consecutive patients undergoing elective isolated CABG were investigated through preoperative duplex scanning of the carotid artery, computed tomography of the chest, and intraoperative ultrasonography of the ascending aorta. Results. Prevalence of carotid stenosis and ascending aortic atherosclerosis was 14.3% (44 of 308) and 30.2% (93 of 308), respectively. Multivariate analysis indicated that significant independent risk factors for carotid stenosis were atherosclerosis of the ascending aorta (p 0.028, odds ratio [OR] 2.16), peripheral vascular disease (p 0.008, OR 4.08), and history of stroke (p , OR 3.73). Significant independent risk factors for ascending aortic atherosclerosis were peripheral vascular disease (p 0.029, OR 3.05), age older than 60 years (p 0.009, OR 2.94), and carotid stenosis (p 0.018, OR 2.27). Modifications on the operative procedure for aortic atherosclerosis were carried out in 49 patients. Overall hospital mortality and morbidity for stroke were 0.97% and 0.65%, respectively. Conclusions. Prevalence of carotid and aortic disease was not low among candidates for CABG. Carotid and aortic screening may help to modify the operative strategy to reduce morbidity of stroke. (Ann Thorac Surg 2000;70:2034 9) 2000 by The Society of Thoracic Surgeons Coronary artery bypass grafting (CABG) is one of the most common operations in the field of cardiovascular surgery today. Despite the increasing number of high-risk patients among CABG candidates, a decrease in mortality in CABG has been observed in recent years, with the exception of patients with acute coronary syndrome. However, morbidity of stroke after CABG remains relatively high due to advanced age and diffuse atherosclerotic disease in candidates for CABG. The incidence of cerebral infarction after CABG is 0.9% to 6.7% as described in recent reports [1 4]. Advanced age [1, 4, 5], peripheral vascular disease [5, 6], prior history of cerebral ischemia [1, 4, 5], and atherosclerosis of the ascending aorta [7] have been identified as risk factors for cerebral infarction after CABG. Because the mechanism responsible for stroke may be different for each risk factor, preoperative surgical strategy accounting for individual mechanisms and risk factors appears to be very important. Therefore, predicting risk factors for stroke based on the preoperative parameters before CABG is necessary for cardiovascular surgeons. The aim of this study was to identify high-risk patients for carotid and aortic atherosclerosis based upon preoperative screenings. Accepted for publication May 24, Address reprint requests to Dr Fukuda, Department of Cardiovascular Surgery, Tsukuba Medical Center Hospital, Amakubo, Tsukuba, Ibaraki, , Japan; fukuda@tmch.or.jp. Patients and Methods Prospective investigation and data collection were performed on 308 consecutive patients undergoing elective isolated CABG between January 1990 and July 1998 at Tsukuba Medical Center Hospital. All patients who underwent scheduled CABG during this time frame were involved regardless of age and symptoms of brain ischemia. One hundred and forty-eight patients requiring urgent CABG during the same period were excluded from this study. Prior to surgery, carotid screening for stenosis of the internal carotid artery and aortic screening for calcification of the ascending aorta was performed on all patients. Intraoperative direct ultrasonographic evaluation of the ascending aorta was also completed as intraoperative screening of ascending aortic atherosclerosis. Carotid Screening B-mode and duplex ultrasonography of the bilateral carotid arteries were performed for carotid screening by the same radiologist before CABG. Criteria in establishing moderate or severe carotid stenosis on the duplex scanning were as follows [3]: (1) increased peak flow velocity of the internal carotid artery greater than 120 cm/sec; (2) decreased peak flow velocity slower than 25 cm/sec; (3) no detection of blood flow signal in the internal carotid artery, which was filled with echogenic material. In the 69 patients who were suspected of having moderate or severe carotid stenosis on the duplex scanning based upon these criteria, cerebral angiography was performed before CABG to evaluate the significance of internal carotid artery stenosis and intracranial vascular lesions. Among these patients, 44 patients who 2000 by The Society of Thoracic Surgeons /00/$20.00 Published by Elsevier Science Inc PII S (00)

2 Ann Thorac Surg FUKUDA ET AL 2000;70: CAROTID AND AORTIC SCREENING 2035 were diagnosed as having stenosis of the internal carotid artery (ICA) greater than 50% (group A) were compared with 264 patients who had no or mild ICA stenosis (group B). There were no complications relevant to cerebral angiography. During the same time period, only 1 patient among those who were referred for CABG was rejected for CABG because of an evolving cerebral infarction due to multiple intracranial arterial stenosis and bilateral internal carotid stenosis. Aortic Screening Plain computed tomography (CT) of the chest was performed before surgery to identify the degree of ascending aortic calcification. The ascending aorta was scanned a slice every 1.5 cm and evaluated by a radiologist. Findings of aortic calcification were classified by the following criteria: grade 0, no calcification on the entire ascending aorta (212 patients); grade 1, scattered calcification smaller than one fourth of ascending aortic circumference (57 patients); grade 2, plate-like calcification larger than one fourth of the ascending aortic circumference and identified on consecutive slices (29 patients); grade 3, so-called porcelain aorta of which the calcification involved the whole circumference and whole length of the ascending aorta (10 patients). Intraoperative direct ultrasonography of the ascending aorta was also performed to evaluate the severity of ascending aortic atherosclerosis before institution of extracorporeal circulation. The atherosclerotic aorta was finally diagnosed based upon intraoperative palpation of the ascending aorta and ultrasonography. The ascending aortic disease was classified by the most prominent feature of the lesion as follows: palpable echogenic plaque of the ascending aorta greater than one fourth of its circumference (n 49), intimal irregularity reflecting atheromatous ulcer of the ascending aorta (n 13), or aortic wall thickening greater than 3.0 mm (n 31). Ninety-three patients who had aortic calcification of grade 2 or 3, or those who had an atherosclerotic aorta, including 9 patients for grade 0 and 45 patients for grade 1 were classified as group C in order to compare with 215 patients whose ascending aortic atherosclerosis was minimal or mild (group D). Definitions of Preoperative Variables Demographic and medical history variables considered to be relevant to the internal carotid artery stenosis (ICA stenosis) and the ascending aortic atherosclerosis (AA atherosclerosis) were collected (Table 1). Hypercholesterolemia was defined as blood cholesterol levels greater than 250 mg/dl at the time of surgical consultation. Obesity was defined as body mass index greater than 33. Significance of coronary lesion was expressed whether or not they had three-vessel disease or left main trunk lesion, or both. The number of anastomoses was also evaluated. Peripheral vascular disease (PVD) was defined as occlusion or stenosis of iliac or femoral arteries diagnosed upon physical findings, angiography, and history of previous peripheral vascular surgery. Angiography of Table 1. Demographic Data of Patients Frequency or Range Mean or Percentage of Patients Age years years 60 years % 70 years % Male gender % Number of grafts 1 5/patient /patient LMT or TVD % Hypertension % Diabetes % Hypercholesterolemia % Previous stroke % Smoker % PVD % Abdominal 5 1.6% aneurysm Obesity % LMT left main trunk lesion; TVD triple-vessel coronary heart disease; PVD peripheral vascular disease. iliac arteries was performed by a cardiologist during coronary angiography when peripheral vascular disease was suspected to coexist. Statistical Analysis All statistical analyses were completed using the SPSS statistical package for Macintosh version 6.0 (SPSS Inc, Chicago, IL). Two separate multivariate analyses were performed to investigate the risk factors for carotid stenosis or ascending aortic atherosclerosis. A univariate analysis was done that analyzed the possible relationships among AA atherosclerosis, ICA stenosis, and the variables collected. Contingency table analyses for categorical data and the Mann-Whitney U test for continuous variables were used. Any variable that achieved a p value of 0.1 or less in the univariate analysis was entered for analysis by multivariate logistic regression with stepwise addition of variables. Results Risk Factors for Carotid and Aortic Disease Demographic data for the analysis of the ICA stenosis are presented in Table 2. Through univariate analysis, significant risk factors for ICA stenosis greater than 50% in CABG candidates were AA atherosclerosis (22 of 44 in group A versus 71 of 264 in group B, p 0.002), PVD (8 of 44 versus 11 of 264, p ), history of stroke (17 of 44 versus 35 of 264, p ), and diabetes (25 of 44 versus 102 of 264, p 0.023). In the multivariate analysis, significant independent risk factors for ICA stenosis were AA atherosclerosis ( p 0.028, odds ratio [OR] 2.16), PVD ( p 0.008, OR 4.08) and history of stroke ( p , OR 3.73). In the multivariate logistic regression model, a probability of prevalence of ICA stenosis in patients who had these three factors was This value was about 10 times greater than that for patients without

3 2036 FUKUDA ET AL Ann Thorac Surg CAROTID AND AORTIC SCREENING 2000;70: Table 2. Risk Factors for Carotid Stenosis Greater Than 50% Parameter Group A (Incidence) Group B (Incidence) Univariate p Multivariate p Odds Ratio [95% CI] Age NS 60 years 34 (77%) 182 (69%) years 17 (39%) 85 (32%) 0.40 Male gender 35 (80%) 193 (73%) 0.37 Obesity 2 (5%) 20 (8%) 0.46 Hypertension 26 (59%) 123 (47%) Diabetes 25 (57%) 102 (39%) Hypercholesterolemia 5 (11%) 52 (20%) 0.74 Smoker 24 (55%) 137 (52%) 0.74 LMT or TVD 35 (80%) 187 (71%) 0.23 Number of anastomoses NS PVD 8 (18%) 11 (4%) [1.45, 11.53] Abdominal aneurysm 2 (5%) 3 (1%) AA lesion 22 (50%) 71 (27%) [1.10, 4.30] Previous stroke 17 (39%) 35 (13%) [1.80, 7.75] Group A (n 44): patients who had carotid stenosis greater than 50%. Group B (n 264): patients who had no or mild carotid stenosis. AA lesion atherosclerosis of the ascending aorta; CI confidence interval; NS not significant; LMT left main trunk lesion; PVD peripheral vascular disease; TVD three-vessel disease. the above factors (Fig 1). Prevalence of carotid occlusion in each age group of every ten years is shown in Table 3. The prevalence of significant ICA stenosis among patients in their 40s was 18.2%. Demographic data for the analysis of AA atherosclerosis are presented in Table 4. By multivariate analysis, significant risk factors for AA atherosclerosis were age older than 60 years (78 of 93 versus 78 of 215, p ), PVD (11 of 93 versus 8 of 215, p ), ICA stenosis (22 of 93 versus 22 of 215, p 0.002), history of stroke (22 of 93 versus 30 of 215, p 0.036) and abdominal aneurysm (4 of 93 versus 1 of 215, p 0.015). Significant independent risk factors for AA atherosclerosis were PVD (p 0.029, OR 3.05), age older than sixty years (p 0.009, OR 2.94) and ICA stenosis (p 0.018, OR 2.27). Carotid Screening and Surgical Modifications Among 44 patients in group A, 7 patients had symptoms of recent brain ischemia including stroke or transient ischemic attack within the previous 6 months. On the other hand, 5 patients in group B had symptoms of recent brain ischemia. In group A, preoperative cerebral angiography demonstrated that 22 patients had carotid stenosis greater than 80%, and 22 patients had carotid stenosis of 50% to 79%. Five of 9 patients who had bilateral carotid stenosis and 2 of 13 patients who had unilateral carotid stenosis greater than 80% had symptoms of recent brain ischemia. Among 22 patients who had carotid stenosis greater than 80%, 5 patients had complete occlusion of a unilateral internal carotid artery and 2 patients had asymptomatic carotid stenosis of 80% to 89%. On the other hand, 15 patients had hemodynamically significant or symptomatic ICA stenosis, which implicated symptomatic ICA stenosis greater than 80% (n 1), ICA stenosis greater than 90% with or without symptoms of brain ischemia (n 5), and bilateral ICA stenosis greater than 80% (n 9). In addition, preoperative cerebral angiography in these 15 patients revealed isolated ICA stenosis or occlusion in 10 patients and combined ICA and intracranial arterial stenosis in 5 patients. In the former subgroup, concomitant carotid endarterectomy (CEA) and CABG with the aid of extracorporeal circulation was performed in 7, precedent CEA followed by CABG in 1, and isolated CABG followed by CEA in 2 patients. These patients recovered without any signs of perioperative stroke. Table 3. Prevalence of Carotid Stenosis Among Age Groups Age Group (n) Years ICA Stenosis 50% (Incidence [95% CI]) ICA Stenosis 80% (Incidence [95% CI]) Fig 1. Logistic regression model for probability of carotid stenosis greater than 50% for each risk factor. AA lesion atherosclerosis of the ascending aorta; PVD peripheral vascular disease (6) (22) 4 (18% [5, 40]) 4 (18% [5,40]) (64) 6 (9% [2, 13]) 3 (5% [0, 24]) (115) 17 (15% [8, 19]) 10 (9% [4, 11]) 70 (101) 17 (17% [10, 20]) 8 (8% 3, 11]) ICA internal carotid artery; CI confidence interval.

4 Ann Thorac Surg FUKUDA ET AL 2000;70: CAROTID AND AORTIC SCREENING 2037 Table 4. Risk Factors for Ascending Aortic Atherosclerosis Parameter Group C (Incidence) Group D (Incidence) Univariate p Multivariate p Odds Ratio [95% CI] Age years 78 (84%) 138 (64%) [1.56, 5.57] 70 years 42 (45%) 60 (28%) Female gender 70 (75%) 158 (73%) 0.74 Obesity 5 (5%) 17 (8%) 0.42 Hypertension 51 (55%) 98 (46%) Diabetes 39 (42%) 88 (41%) 0.87 Hypercholesterolemia 15 (16%) 42 (20%) 0.48 Smoking 19 (20%) 112 (52%) 0.92 LMT/TVD 74 (80%) 148 (69%) Number of anastomoses NS PVD 11 (12%) 8 (4%) [1.23, 8.32] Abdominal aneurysm 4 (4%) 1 (0%) ICA stenosis 22 (24%) 22 (10%) [1.15, 4.9] Previous stroke 22 (24%) 30 (14%) ICA internal carotid artery stenosis; LMT left main trunk lesion; PVD peripheral vascular disease; TVD three-vessel disease; CI confidence interval; NS not significant. Among 5 patients with critical ICA stenosis and intracranial arterial stenosis, 1 patient who underwent concomitant CEA and CABG developed a stroke after surgery. Two patients who underwent isolated CABG with the aid of extracorporeal circulation maintaining a perfusion pressure higher than 80 mm Hg and 2 patients who underwent off-pump double CABG recovered without any neurologic sequelae. Aortic Screening and Surgical Modification The relationship between plain chest CT and intraoperative ultrasonography is shown in Table 5. Among 212 patients who were diagnosed as having grade 0 calcification, 203 patients (95.8%) had normal ultrasonic findings of the ascending aorta. On the other hand, among 57 patients who were diagnosed as having grade 1 calcification, 12 patients (21.0%) had normal ultrasonic findings. All patients who had grade 2 or 3 calcification of the Table 5. Comparison Between Plain Chest Computed Tomography and Intraoperative Ultrasonography Normal Ultrasonographic Findings Plaque Irregular Plaque Thickening Grade Grade Grade Grade Findings were classified upon most prominent feature of the lesion. Grade 0: no calcification on the ascending aorta. Grade 1: scattered calcification smaller than one fourth of ascending aortic circumference. Grade 2: plate-like calcification larger than one fourth of ascending aortic circumference. Grade 3: porcelain aorta of which calcification involved the whole circumference and whole length of the ascending aorta. Plaque on ultrasonography: palpable echogenic plaque of the ascending aorta greater than one fourth of its circumference. Intimal irregularity: mobile, frail atheroma in the ascending aorta. Aortic wall thickening: thickening of the ascending aorta greater than 3.0 mm. ascending aorta exhibited abnormal ultrasonic findings of the ascending aorta. In group C, among 93 patients, 44 patients had routine cannulation, 29 had a change in arterial cannulation site, 15 underwent the no-touch technique, and 5 had offpump surgery. Safe arterial access and clamping sites were definitively confirmed by intraoperative direct ultrasonography of the ascending aorta. The alternative arterial access site was the mid portion of the ascending aorta in 21, the femoral artery in 5, and the axillary artery in 3 patients. In the aortic no-touch group, arterial access was selected in either the axillary artery (n 7), the femoral artery (n 7), or aortic arch (n 1). Intraoperative ultrasonography was the ultimate factor for making the final decision in regard to surgical strategy. Mortality and Morbidity There were 3 hospital deaths (hospital mortality of 0.97%). Causes of death were arrhythmia in 1 (day 4), rupture of abdominal aneurysm in 1 (day 35), and pneumonia in 1 (day 77). There were 2 perioperative strokes (morbidity of 0.65%). One patient in group A who underwent concomitant CABG and CEA suffered a stroke owing to intraoperative low brain perfusion. This patient had a tandem lesion in the cervical and intracranial portion of the left internal carotid artery. Although a temporary shunt was employed during CEA, ischemia-reperfusion injury of the brain might have been induced by pressure drop during surgery. Because scant blood supply from the contralateral carotid artery to the distal region of the affected artery was demonstrated in preoperative cerebral angiography, a two-stage strategy should have been adopted in this patient. The other patient in group B had a small lacunar infarction in the basal ganglia on day 2. Since the cerebral angiography performed after the onset of stroke revealed an intact internal carotid artery and multiple intracranial arterial stenoses, a drop in blood pressure during the postoperative period seemed to have been responsible. The former pa-

5 2038 FUKUDA ET AL Ann Thorac Surg CAROTID AND AORTIC SCREENING 2000;70: tient was seriously disabled, but the latter patient recovered with partial disability. Comment Because atherosclerosis is a systemic disorder, patients with ischemic heart disease frequently have atherosclerosis of other organs. Coronary artery bypass grafting has become a popular surgical procedure for patients with severe coronary artery disease. Although it generally has positive results, CABG is sometimes associated with adverse neurologic outcomes including neuropsychic damage, transient ischemia, and stroke. Because perioperative stroke is as much disabling as lethal, it will reduce the benefits of surgical intervention and require longterm hospitalization with increased medical cost. However, the incidence of stroke after CABG has recently increased owing to extended surgical indications for high-risk or aged patients. Several parameters were detected as risk factors of stroke after coronary artery bypass grafting. Gardner and associates [8] reported that age, previous cerebrovascular disease, pump time, severe perioperative hypotension, and atherosclerosis of the ascending aorta were univariate predictors of stroke following CABG. Lynn and coworkers [9] suggested that diabetes, mural thrombi, and aortic calcification were predictors of postoperative permanent neurological deficits by multivariate analysis. The different conclusions drawn from these reports suggest that several mechanisms of stroke may be present in high-risk populations. In other words, the cause of stroke after CABG is multifactorial. Among these mechanisms, atheroembolism from the ascending aorta and cerebral hypoperfusion due to carotid occlusive disease seem to be major causes of postoperative stroke [1, 2, 7, 10]. Other mechanisms inducing stroke after CABG, such as detachment of ventricular mural thrombus, air embolism, and perioperative arrhythmia, can be prevented through careful intraoperative and postoperative management. However, prevention of atheroembolism and brain hypoperfusion during surgery depends upon preoperative and intraoperative surgical evaluation. Therefore, preoperative and intraoperative screening is important. On the other hand, because medical costs have increased markedly, it is necessary to be aware of excessive and unnecessary screening tests that increase medical cost and are time consuming. In this study, we investigated the prevalence and risk factors of carotid and aortic atherosclerosis in order to determine what type of screening would be most efficient. Berens and colleagues [11] screened the carotid arteries of 1087 patients undergoing heart surgery by duplex scanning. In their report, ICA stenosis greater than 50% and 80% was found in 17.0% and 5.9% of patients, respectively. In our study with duplex scanning and carotid angiography, the prevalence of carotid disease greater than 50% and 80% in CABG candidates in a Japanese population were 14.3% and 7.1%, respectively. Since we established the significance of carotid stenosis by cerebral angiography, evaluation of the degree of carotid stenosis was definite. Our results suggested that the prevalence of carotid artery disease in patients scheduled for CABG was almost identical when comparing Western and Oriental populations. The role of carotid stenosis in disturbed cerebral circulation has been controversial. Schwartz and associates [13] reported that in patients with significant, complete or bilateral carotid artery occlusion, morbidity by perioperative stroke was clearly elevated. Brener and associates [14] reported a 9.2% stroke incidence of transient ischemic attack and cerebrovascular accident in patients having coronary artery bypass grafting with 50% or greater carotid stenosis and a 20% stroke rate in patients with significant carotid stenosis contralateral to internal carotid occlusion. Based on these data, the authors insisted that preoperative carotid screening had a clinical impact on the prevention of postoperative stroke in CABG. This study identified the risk factors for carotid stenosis in CABG candidates as AA atherosclerosis, arteriosclerosis of the lower extremities, and history of stroke. In previously published data, advanced age was one of the risk factors for perioperative stroke [12, 15]. Faggiloli and coworkers [1] recommended preoperative carotid screening in patients older than 60 years of age because the prevalence of carotid artery disease was high in this group of patients. However, Salasidis and associates [6] reported that advanced age was not a risk factor for carotid disease. Our results exhibited that the prevalence of significant carotid artery disease was not low even in younger patients in their 40s. In addition, advanced age was not a risk factor for carotid artery disease in our study. Therefore, we recommend carotid screening before CABG in all candidates regardless of age. Atheroembolism from the diseased ascending aorta has been recognized as a major problem, other than cerebral hypoperfusion, in CABG especially in elderly patients [10, 15]. Lynn and coworkers [9] reported that one of the significant risk factors for stroke was aortic calcification detected by intraoperative examination. As for the evaluation of the atherosclerotic ascending aorta, many authors described efficacy of aortic screening by plain CT of the chest or intraoperative ultrasonography [16 20]. The CT is sensitive in detecting fine calcification of the ascending aorta. Information regarding the significance of aortic calcification is beneficial in planning surgery as to the choice of graft material, arterial access, and myocardial protection [16]. Preoperative diagnosis of extensive aortic calcification, the so-called porcelain aorta, is also especially important when planning surgery. On the other hand, intraoperative ultrasonic imaging is sensitive in detecting fragile, atheromatous thickening of the aorta [18, 17]. In this study we obtained intraoperative information regarding risky atheroma of the ascending aorta, and these findings assisted surgeons in determining a safe site for aortic cannulation and clamping. In our investigation, advanced age was noted as a risk factor for AA atherosclerosis. Extensive calcification or significant atheromatous degeneration was rarely seen in patients under 60 years of age. Because we aggressively use arterial conduits in patients younger than 70 years of

6 Ann Thorac Surg FUKUDA ET AL 2000;70: CAROTID AND AORTIC SCREENING 2039 age, inflow of graft conduit may be assigned to in-situ arterial grafts when atherosclerotic change of the ascending aorta is significant. In elderly patients, we usually decide the choice of graft material and arterial access before surgery. If combined carotid and aortic disease is suggested to exist before surgery, we have adopted off-pump surgery recently. Although Wareing and colleagues [17] recommended aggressive surgical treatment of diseased ascending aorta based on intraoperative ultrasonic imaging, our strategy for diseased aorta was principally a no-touch method, employing induced ventricular fibrillation with or without deep hypothermic circulatory arrest or off-pump CABG [21]. We did not apply replacement of diseased ascending aorta with tube graft because extensive replacement of the aorta seemed to be necessary. As for arterial access in patients with diseased aorta, the femoral artery was the primary choice because of easy access. Because retrograde perfusion from the femoral artery may dislodge atheromatous debris from the iliofemoral region, preoperative evaluation of peripheral vascular disease is important. When retrograde perfusion seemed to be risky, we chose the axillary artery as an alternative arterial access [22]. Because of its small size, we anastomosed artificial graft to the axillary artery when it was of small size. However, recent improvements in arterial cannulas have made it easier to access this artery. Recently, we have employed a 17F or 19F Biomedicus cannula (Medtronic Inc, Minneapolis, MN) when patients were of small stature, because it had a thin wall and low resistance. In our study, carotid stenosis and AA atherosclerosis sometimes coexisted in CABG candidates. This reflects the fact that both are based upon systemic arteriosclerosis. In such conditions, it is important to maintain adequate perfusion pressure during the perioperative period in order to prevent hypoperfusion of the brain. Current progress in the technique and device made it easy for us to apply off-pump CABG in patients with diffuse atherosclerosis. The off-pump technique could avert both embolism from the ascending aorta and cerebral hypoperfusion due to hypotension. Although information by plain chest CT is limited, we believe preoperative evaluation of the ascending aorta is of great help in making operative strategies in elderly patients. In conclusion, preoperative carotid screening was efficient in CABG candidates. We recommend its use for all CABG candidates regardless of age. Preoperative aortic screening with CT provided us useful information related to the planning of surgery in elderly patients. 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