Management Strategy for Simultaneous Carotid Endarterectomy and Coronary Revascularization

Management Strategy for Simultaneous Carotid Endarterectomy and Coronary Revascularization Gregory D. Trachiotis, MD, and Albert J. Pfister, MD Washington Heart, Section for Thoracic and Cardiovascular Surgery, The Washington Hospital Center, Washington, DC Background. The occurrence of significant carotid artery disease in patients requiring coronary artery bypass grafting (CABG) results in a dilemma regarding the best surgical management. Our philosophy has been to perform simultaneous carotid endarterectomy and CABG. We reviewed the efficacy of this therapy in patients treated at a large community-based hospital. Methods. During a 6-year period, from 1990 to 1996, 88 patients underwent simultaneous carotid endarterectomy and CABG. All patients underwent preoperative fourvessel arch arteriography and standard coronary angiography. The principal indications for combined procedures were the need for CABG and (1) symptomatic carotid artery disease; (2) internal carotid artery stenosis of 80% or more, with or without contralateral disease; or (3) an ulcerated, unstable internal carotid artery lesion, regardless of degree of stenosis. The average patient age was 68 years, and there was a 3:1 male-to-female predominance. All procedures were performed with the patients under general anesthesia. The carotid endarterectomy was performed first, and an intraluminal shunt was used in all patients. Results. The average degree of stenosis on the operated side was 86.2%. An average of 3.6 coronary bypasses per patient were performed. Morbidity included four strokes (4.5%). There were no perioperative myocardial infarctions. There were three hospital deaths (3.4%). The combined permanent stroke and mortality rate was 6.8%. Univariate predictors of stroke were an elevated serum creatinine level, a pulmonary complication, and left main coronary artery disease. Univariate predictors of hospital death were stroke, an elevated serum creatinine level, peripheral vascular disease, and left main coronary artery disease. Multivariate predictors of a prolonged hospitalization were stroke, an elevated serum creatinine level, and a pulmonary complication. Eighty-five patients (96.6%) were discharged and alive at 30 days. Conclusions. In the context of the indications we used to select patients for simultaneous carotid endarterectomy and CABG, the combined permanent stroke and mortality rate was less than 7%. Our management strategy identified patients that were at increased surgical risk as a result of advanced carotid and coronary artery disease. In our practice, simultaneous carotid endarterectomy and CABG is the preferred surgical approach for these high-risk patients and results in a low in-hospital morbidity and mortality using a single anesthetic and hospitalization. (Ann Thorac Surg 1997;64:1013 8) 1997 by The Society of Thoracic Surgeons The presence of significant carotid artery disease in patients requiring coronary artery bypass grafting (CABG) poses a dilemma regarding the best surgical management to undertake in this high-risk population. Carotid endarterectomy (CEA) done in patients with severe uncorrected coronary artery disease has been associated with perioperative myocardial infarction rates as high as 17% and operative mortality rates of up to 20%, with myocardial infarctions accounting for as many as 60% of these deaths [1, 2]. There is a 14% risk of perioperative stroke in patients with severe carotid artery disease who undergo CABG, and the stroke rate remains 4% per year for the first 4 years after coronary revascularization [2 4]. Several centers have reported satisfactory results in patients with coexisting carotid and coronary disease who undergo simultaneous CEA and CABG [3 16] or a staged CEA and CABG [4, 17, 18] or in whom Presented at the Poster Session of the Thirty-third Annual Meeting of The Society of Thoracic Surgeons, San Diego, CA, Feb 3 5, 1997. Address reprint requests to Dr Pfister, Washington Heart, 1706 New Hampshire Ave NW, Washington, DC 20009. hypothermic circulatory arrest is used [19]. Nonetheless, in multiple previous reviews, higher incidences of myocardial infarction, stroke, and death have been noted in those patients with advanced age, unstable angina, or multivessel coronary artery disease with or without left main coronary artery disease, a carotid stenosis of 80% or more, a prior stroke or transient ischemic attack, and a nonelective operation regardless of the operative strategy [3 7, 17 20]. In addition, between 3% and 12% of patients who present with symptoms related to coronary artery disease have been reported to have significant internal carotid artery (ICA) stenosis (more than 70% diameter narrowing), and this is a recognizable source of morbidity and mortality in this high-risk population [4, 6, 21, 22]. Currently there is no multicenter, prospective trial comparing the different operative approaches, and we now rely on the patient selection criteria used at and the results from individual institutions with experience using a particular treatment strategy. Our cardiovascular surgery practice is at a large tertiary-care referral center and consists of patients from the greater metropolitan Washington, DC, area and the 1997 by The Society of Thoracic Surgeons 0003-4975/97/$17.00 Published by Elsevier Science Inc PII S0003-4975(97)00795-0

1014 TRACHIOTIS AND PFISTER Ann Thorac Surg SIMULTANEOUS CEA AND CABG 1997;64:1013 8 surrounding four states. Most of the patients referred have symptomatic coronary artery disease that requires nonelective operative management and often have coexisting multisystem atherosclerotic disease that requires prompt evaluation. It has been our philosophy to manage patients with coexisting significant carotid artery disease who require coronary revascularization using simultaneous CEA and CABG. We report the early results from our use of simultaneous CEA and CABG between 1990 and 1996 at the Washington Hospital Center. The study premise was that the early outcomes in our patients with carotid artery disease requiring CABG identified to be at risk for adverse neurologic and cardiac events who undergo simultaneous CEA and CABG support our management strategy. Material and Methods All patients having concomitant CEA and CABG were identified from a computerized registry of 12,047 adult cardiac procedures performed at the Washington Hospital Center between April 1990 and April 1996. The records of 88 consecutive patients were retrospectively reviewed for demographic information, clinical and angiographic data, operative characteristics, and results. Nearly all patients in this study were referred to the hospital because of cardiac symptoms. Their carotid artery disease was diagnosed incidentally or on the basis of previous medical records. Noninvasive carotid artery testing was performed in all patients with a history of neurologic symptoms, a previous stroke, a previous CEA, an audible carotid bruit, previously positive oculoplethysmography findings, or evidence of multisystem vascular disease. All patients were identified as having moderate (50% to 80%) to severe (80% to 99%) stenosis or a 100% occlusion of either or both carotid arteries by noninvasive carotid testing and underwent subsequent four-vessel aortic arch angiography. A diameter reduction of more than 70% of the ICA relative to the normal distal ICA shown by angiography was considered to represent severe stenosis. The absolute indications for simultaneous procedures were the need for CABG and (1) symptomatic carotid artery disease (defined as either a transient ischemic attack or a stroke occurring 4 or more weeks before CABG); (2) ICA stenosis of 80% or more, with or without contralateral disease; or (3) an ulcerated, unstable ICA lesion, regardless of the degree of stenosis. Our selection criteria were not absolute, however, but also took into consideration the findings from careful patient examination and clinical judgment. For example, a patient may have had an asymptomatic, unilateral ICA stenosis of more than 70% but was considered a candidate for a combined procedure if there was an associated ulcerative plaque or contralateral disease identified by the noninvasive carotid imaging study or by carotid arteriography, or if there were numerous preoperative clinical factors that were deemed potential risks for an adverse postoperative neurologic event. All patients underwent CABG and one CEA performed concomitantly under general anesthesia. The CEAs were performed by the vascular surgeon in our group before cardiopulmonary bypass (CPB) and myocardial revascularization. An intraluminal carotid shunt was used in all patients. After completion of the CEA, the neck incision was left open until heparin reversal after CPB. During CEA, saphenous vein conduits were prepared, though sternotomy was routinely done after CEA. After CEA, standard CABG was performed with CPB in 84 patients (95.5%) and without CPB in 4 (4.5%). In those patients who had CPB, myocardial protection was achieved using antegrade (aortic root) and retrograde (coronary sinus), hyperkalemic, cold blood cardioplegia. In all patients the mean systemic arterial pressure was maintained between 70 and 80 mm Hg. The proximal anastomoses in patients who had CPB were performed primarily using a single aortic cross-clamp technique. A perioperative myocardial infarction was defined as the occurrence of new Q waves, persistent ST segment changes correlated with an elevated myocardial fraction of creatinine kinase, or a new left bundle-branch block. Strokes were reported as being reversible or permanent, and the deficit was reported as occurring ipsilateral or contralateral to the CEA. An urgent operation was defined as an operative procedure performed in a patient with progressive or nonmedically manageable symptoms that necessitated his or her hospitalization or considered too unstable to permit the patient s discharge from the hospital before an operative intervention. An emergency operation was defined as a procedure performed on a patient because of cardiovascular instability or one that replaced another scheduled operation. Follow-up clinical information about survival and subsequent coronary or neurologic events was obtained for the period of the hospitalization and up to 30 days postoperatively. Information on long-term survival or events was unavailable and not recorded in the data base. Univariate and multivariate predictors of hospital death, postoperative stroke, and prolonged postoperative stay (defined as 20 days or more) were determined using two-tailed Fisher s exact test, t test, Pearson correlation, and stepwise regression. A p value of less than 0.05 was statistically significant. Factors tested as predictors of the various postoperative events are listed in Appendix 1. Results The distribution of important demographic and clinical characteristics in the patients is shown in Table 1. More than 90% of the patients had symptoms related to coronary artery disease, and there was a significant history of known carotid disease in more than 55%. The risk factors for atherosclerotic disease in the patients included age exceeding 70 years (45.5%), smoking history (76.1%), hypertension (69.3%), diabetes (36.4%), and peripheral vascular disease (23.9%). The salient angiographic features in the patient population are listed in Table 2. Triple-vessel or left main coronary artery disease, or both, were present in more than 85% of patients. Sixty-three (71.5%) patients had

Ann Thorac Surg TRACHIOTIS AND PFISTER 1997;64:1013 8 SIMULTANEOUS CEA AND CABG 1015 Table 1. Demographic and Clinical Characteristics Characteristic No. of Patients a Table 3. Operative Characteristics Characteristic Patients a Age Mean standard deviation (y) 68.4 8.2 Range (y) 49 87 70 y 45.5% Sex Male 63 (71.6) Female 25 (28.4) Smoking history 67 (76.1) Hypertension 61 (69.3) Diabetes 32 (36.4) Peripheral vascular disease 21 (23.9) Creatinine (mg/dl) Mean standard deviation 1.29 0.44 Range 0.9 2.7 Cardiac history Unstable angina 61 (69.3) Prior myocardial infarction 45 (51.1) Exertional angina 19 (21.6) Prior coronary artery bypass grafting 10 (11.4) Congestive heart failure 10 (11.4) Asymptomatic 8 (9.1) Neurologic history Asymptomatic bruit 47 (53.4) Transient ischemic attacks 23 (26.1) Prior stroke 19 (21.6) Prior carotid endarterectomy 10 (11.4) some degree of left ventricular dysfunction, although only 2 had an ejection fraction of less than 0.25. All patients had significant unilateral carotid artery stenosis on the operated side, and contralateral disease was identified in 29 (33%). Of these 29 patients, nearly half had a total occlusion on the nonoperated side. Moreover, the average degree of stenosis on the contralateral side Table 2. Angiographic Data Finding No. of Patients a Coronary artery disease Triple vessel 54 (61.4) Left main coronary artery 22 (25) Left ventricular function (ejection fraction) Normal ( 0.50) 25 (28.4) Mildly depressed ( 0.39 0.50) 42 (47.8) Moderately depressed (0.25 0.39) 19 (21.6) Severely depressed ( 0.25) 2 (2.2) Carotid artery disease Unilateral 88 (100) % stenosis on operated side 86.2 (range, 70 99) Contralateral 29 (32.9) % stenosis on nonoperated side 81.6 (range, 30 100) Total occlusion 14 (48.2) Operative priority Elective 28 (31.8) Urgent 57 (64.8) Emergent 3 (3.4) Coronary artery bypass grafting Number of grafts Mean standard deviation 3.6 1.1 Range 1 7 Internal mammary artery 32 (36.4) Cross-clamp time (min) Mean standard deviation 44.5 17.3 Range 18 104 Cardiopulmonary bypass (min) Mean standard deviation 72.3 23.7 Range 34 140 Carotid endarterectomy: unilateral 88 (100) (81.6%) was comparable with that on the operated side (86.2%). The operative characteristics in the study group are listed in Table 3. Nonelective operations accounted for 68% of all procedures. Thirty-two (36.4%) patients received an internal mammary artery graft. All patients had a unilateral CEA. The incidences of in-hospital and 30-day postoperative events are listed in Table 4. Of the three deaths, two were due to a postoperative stroke and one was related to multisystem organ failure and subsequent ventricular arrhythmia. Of the four postoperative strokes, all were ipsilateral to the CEA, although 2 patients also had a contralateral occlusion. One stroke was reversible, and three (3.4%) were permanent. Two of the 4 patients with a stroke died. All four strokes occurred after the first postoperative day (range, 3 to 16 days), and a pulmonary complication (defined as a need for the reinstitution of or for prolonged mechanical ventilation necessitated by underlying pulmonary pathology) preceded the stroke in 3 of the patients. There were no perioperative myocardial infarctions. There were no complications or deaths in the 4 patients who had a simultaneous CEA and CABG without CPB. The combination of permanent stroke and death occurred in 6.8% of our patient population. The operative results from simultaneous CEA and CABG published during more than 10 years in series containing more than 75 patients are compared with the results in our patients in Table 5. The significant predictors of postoperative stroke, prolonged postoperative stay, and hospital death are listed in Table 6. Because there were so few postoperative strokes and deaths, only the length of postoperative stay could be used for multivariate analysis. The presence of renal insufficiency (serum creatinine, 2 mg/dl) was found to have a unique adverse impact in terms of the occurrence of a postoperative stroke, prolonged hospital stay, and death. The development of a postoperative

1016 TRACHIOTIS AND PFISTER Ann Thorac Surg SIMULTANEOUS CEA AND CABG 1997;64:1013 8 Table 4. In-Hospital and 30-Day Postoperative Events and Complications Characteristic Patients a Death 3 (3.4) Hospital/30-day 3/0 (stroke 2; arrhythmia/multisystem organ failure 1) Myocardial infarction 0 Pulmonary complications 8 (9.1) Transient ischemic attacks 1 (1.1) Stroke 4 (4.5) Postoperative (3 16 days) 4 (4.5) Ipsilateral 4 (4.5) Reversible 1 (1.1) Permanent 3 (3.4) Fatal 2 (2.3) Combined total stroke and death 7 (7.9) Intensive care unit stay Mean standard deviation 3.7 5.8 (days) Range (days) 1 23 7 days 89 Hospital stay (days) Mean standard deviation 15.7 18.7 Range 5 107 Median 9 Discharged 85 (96.6) pulmonary complication had a deleterious impact in terms of the occurrence of a postoperative stroke and prolonged hospital stay. There was a clear association between a postoperative stroke and a prolonged hospital stay and death. The presence of left main coronary artery disease was a predictor of both postoperative stroke and Table 6. Univariate and Multivariate Predictors of Hospital Events Event Predictor p Value Hospital death Postoperative stroke 0.009 Elevated creatinine ( 2 mg/dl) 0.002 Peripheral vascular disease 0.007 Left main coronary artery disease 0.013 Postoperative Elevated creatinine 0.002 stroke Pulmonary complication 0.008 Left main coronary artery disease 0.045 Postoperative stay Postoperative stroke 0.04 ( 20 days) Elevated creatinine 0.07 Pulmonary complication 0.001 a Postoperative stay ( 10 days) Internal mammary artery use 0.019 a a Multivariate predictor. death. Although the use of an internal mammary artery graft with or without saphenous vein grafting was a predictor of a shorter hospitalization, it had no impact on morbidity or mortality. Comment The combined stroke and mortality rate was less than 8% in our patients selected for simultaneous CEA and CABG on the basis of our criteria. The recent reports by Daily [16], Akins [5], and Rizzo [7] and their associates, as well as those of others [6, 8 16], have also demonstrated the safety and efficacy of simultaneous CEA and CABG. However, equivalent results have been obtained by others using a staged CEA and CABG [4, 17, 18] or even hypothermic circulatory arrest [19], although the degree of patient risks factors varied among reports. We do not argue that there are no other acceptable surgical options Table 5. More Than 10-Year Experience With Simultaneous Carotid Endarterectomy and Coronary Artery Bypass Grafting Reported in Series With More Than 75 Patients Series Patients Mean Age (y) Myocardial Infarction Permanent Stroke Deaths Total Permanent Stroke and Death Jones et al, 1984 [17] 132 62 1 (0.8) 2 (1.6) 4 (3.0) 6 (4.6) Reul et al, 1986 [12] 143...... 4 (2.8) 6 (4.2) 10 (7.0) Dunn, 1986 [13] 130 60... 5 (3.8) 6 (4.6) 11 (8.4) Hertzer et al, 1989 [4] 170 65... 9 (5.3) 9 (5.3) 18 (10.6) Minami et al, 1989 [14] 116 69 2 (1.7) 2 (1.7) 2 (1.7) 4 (3.4) Vermeulen et al, 1992 [15] 230 63 4 (1.8) 7 (3.0) 8 (3.5) 15 (6.5) Rizzo et al, 1992 [7] 127 65 6 (4.7) 7 (5.5) 7 (5.5) 14 (11.0) Akins et al, 1995 [5] 200 67 5 (2.5) 6 (3.0) 7 (3.5) 13 (6.5) Mackey et al, 1996 [6] 100 68 6 (6.0) 9 (9.0) 8 (8.0) 17 (17.0) Daily et al, 1996 [16] 100 68 1 (1.0) 0 (0.0) 4 (4.0) 4 (4.0) Total 1,448 65 25 (2.5) 48 (3.3) 64 (4.2) 112 (7.7) Present report 88 68 0 3 (3.4) 3 (3.4) 6 (6.8)

Ann Thorac Surg TRACHIOTIS AND PFISTER 1997;64:1013 8 SIMULTANEOUS CEA AND CABG 1017 for managing patients with severe coexisting carotid and coronary artery disease. Yet, without a large, multicenter, prospective study comparing different operative strategies in patients selected using similar criteria, each institution must adopt a consistent management scheme that produces outcomes comparable to those described in other published reports. The incidence of postoperative ipsilateral permanent neurologic sequelae (3.4%) and the incidence of death (3.4%) in this report compare favorably with those in the literature for patients with severe coexisting carotid and coronary artery disease managed using a combined procedure (see Table 5) or any other operative strategy [3 19]. Although there have been a few reports of a slightly higher incidence of stroke, myocardial infarction, and death in patients undergoing a combined CEA and CABG than in those undergoing only a CEA [7, 16, 18] or CABG [7, 9, 16, 17, 22], there were marked differences in the severity of the arterial pathology and in the risk factors that could account for this. It has been well established by Hertzer [1 4] and others [5 7, 22 25] that patients with significant coexistent carotid and coronary artery disease represent a higher-risk population than those with isolated carotid or coronary atherosclerosis. In particular, D Agostino [25] and Berens [23] and their colleagues identified predictors of a significant carotid stenosis (80% or greater) in patients evaluated for coronary artery surgery to be a preoperative age of more than 70 years, diabetes, left main coronary artery disease, peripheral vascular disease, female sex, prior vascular operation, prior stroke or transient ischemic attack, and smoking. Recently Schwartz [21], Salisidis [22], Berens [23], and Mickelborough [24] and their colleagues demonstrated that preoperative risk factors for a postoperative neurologic event in patients undergoing cardiopulmonary bypass are a carotid stenosis of 80% or more, carotid occlusion, prior stroke or transient ischemic attack, peripheral vascular disease, postinfarction angina, and prolonged cardiopulmonary bypass times. There is also compelling data demonstrating an increased incidence of stroke in patients undergoing CABG alone who have an asymptomatic carotid stenosis of 80% or more, or who have a carotid occlusion with or without contralateral carotid disease [21, 22, 24]. Many of these described clinical risk factors and angiographic characteristics were present in high percentages of our patient population, and this lends support to our belief that the criteria we have used to select patients for a combined CEA and CABG have been very useful in identifying those at risk for an adverse neurologic outcome. We must also emphasize that, in the patients in those studies identifying risk factors for a postoperative stroke and in those series of patients who underwent combined CEA and CABG, a postoperative stroke was demonstrated contralateral to the CEA in 20% to 60% and was attributed to multifactorial causes (eg, aortic debris) in up to two thirds of patients who suffered postoperative neurologic events [7, 19, 23, 24]. The four strokes in our study were ipsilateral to the CEA and likely resulted from extracranial disease, especially since 2 of these patients had a contralateral carotid occlusion. In a select subgroup of patients who had a contralateral occlusion and renal insufficiency and had undergone a prior CABG or who had diffuse ascending aortic disease but a single diseased coronary artery, a simultaneous CEA and CABG without cardiopulmonary bypass was performed without sequelae in 4. This particular operative approach perhaps addresses the other confounding multiple risk factors that may have an adverse impact on the neurologic outcome. Finally, in accordance with reports by Hertzer and associates [1 3], the fact that no patient in our series sustained a perioperative myocardial infarction despite the diffuse nature of the coronary artery disease, the high incidence of left main coronary artery disease, the presence of left ventricular dysfunction in more than 25% of patients, and the need for urgent coronary revascularization support our use of early, rather than staged, CABG in patients who present with coexisting carotid artery disease and symptomatic coronary artery disease. We have therefore not only identified potential risk factors for adverse neurologic outcomes in patients requiring coronary revascularization but also identified a patient population at risk for adverse cardiac events that has benefited from intraoperative management strategies that address both the carotid artery disease and the coronary artery disease. Although we were unable to demonstrate long-term protection from an ipsilateral stroke, myocardial infarction, or death in our patient population because of the wide geographical referral pattern and inability to record follow-up data, Hertzer [3], Akins [5], and Rizzo [7] and their associates, who performed combined CEA and CABG in patient populations similar to ours, as have reported the following long-term actuarial event-free and survival rates: survival at 5 years, more than 70%; freedom from ipsilateral stroke at 5 or 10 years more than 91%; and 10-year freedom from myocardial infarction, 81%. Daily and associates [16] have also reported the potential cost benefit to be gained from performing simultaneous CEA and CABG by comparing the costs of a combined procedure with the combined costs for isolated procedures. These results are likely to differ among institutions, and because simultaneous CEA and CABG represents less than 0.7% of adult cardiac procedures in our practice, it is unlikely that there is a dramatic cost benefit to either the patient or hospital. The cost to the patient is more likely to be influenced by the occurrence of a postoperative complication and a prolonged hospital stay. We were able to demonstrate low incidences of in-hospital stroke, myocardial infarctions, and death, with a median intensive care unit stay of 1 day, a median hospital stay of 9 days, and a 30-day survival of 96.6%. In summary, simultaneous CEA and CABG is the preferred surgical approach for a patient with severe combined carotid and coronary artery disease at the Washington Hospital Center. In our practice, patients selected for simultaneous CEA and CABG have identifiable risk factors for adverse neurologic or cardiac outcomes. The simultaneous performance of CEA and

1018 TRACHIOTIS AND PFISTER Ann Thorac Surg SIMULTANEOUS CEA AND CABG 1997;64:1013 8 CABG in patients with severe coexisting carotid artery disease who require coronary revascularization has proved to be a safe and efficacious operative strategy in these high-risk patients. It also potentially eliminates the cost of a subsequent hospitalization required for a second operation or for a stroke resulting from uncorrected carotid artery disease. References 1. Hertzer NR, Lees CD. Fatal myocardial infarction following carotid endarterectomy. Ann Surg 1981;194:212 8. 2. Lees CD, Hertzer NR. Postoperative stroke and late neurologic complications after carotid endarterectomy. Arch Surg 1981;116:1561 8. 3. Hertzer NR, Loop FD, Taylor PC, Beven EG. Combined myocardial revascularization and carotid endarterectomy. J Thorac Cardiovasc Surg 1983;85:577 89. 4. Hertzer NR, Loop FD, Beven EG, O Hara PJ, Krajewski LP. Surgical staging for simultaneous coronary and carotid disease: a study including prospective randomization. J Vasc Surg 1989;9:455 63. 5. Akins CA, Moncure AC, Daggett WM, et al. Safety and efficacy of concomitant carotid and coronary artery operations. Ann Thorac Surg 1995;60:311 8. 6. Mackey WC, Khabbaz K, Bojar R, O Donnell TF. Simultaneous carotid endarterectomy and coronary artery bypass: perioperative risk and long-term survival. J Vasc Surg 1996; 24:58 64. 7. Rizzo RJ, Whittemore AD, Couper GS, et al. Combined carotid and coronary revascularization: the preferred approach to the severe vasculopath. Ann Thorac Surg 1992;54: 1099 109. 8. Pome G, Passini L, Colucci V, et al. Combined surgical approach to coexistent carotid and coronary artery disease. J Cardiovasc Surg 1991;32:787 93. 9. Perler BA, Burdick JF, Williams GM. The safety of carotid endarterectomy at the time of coronary artery bypass surgery: analysis of results of a high-risk patient population. J Vasc Surg 1985;2:558 63. 10. Vassilidze TV, Cernaianu AC, Gaprindashvili T, Gallucci JG, Cilley JH, DelRossi AJ. Simultaneous coronary artery bypass and carotid endarterectomy. Tex Heart Inst J 1994;21:119 24. 11. Babu SC, Shah PM, Singh BM, Semel L, Clauss RH, Reed GE. Coexisting carotid stenosis in patients undergoing cardiac surgery: indications and guidelines for simultaneous operations. Am J Surg 1985;150:207 11. 12. Reul GJ, Cooley DA, Duncan JM, et al. The effect of coronary artery bypass on the outcome of peripheral vascular operations in 1093 patients. J Vasc Surg 1986;3:788 98. 13. Dunn EJ. Concomitant cerebral and myocardial revascularization. Surg Clin North Am 1986;66:385 95. 14. Minami K, Gawaz M, Ohlmeier H, Vyska K, Korfer R. Management of concomitant occlusive disease for coronary and carotid arteries using cardiopulmonary bypass for both procedures. J Cardiovasc Surg 1989;30:723 8. 15. Vermeulen FEE, Hamerlijnk RPHM, Defauw JJAM, Ernst SMPG. Synchronous operation for ischemic cardiac and cerebrovascular disease: early and long-term follow-up. Ann Thorac Surg 1992;53:381 90. 16. Daily PO, Freeman RK, Dembitsky WP, et al. Cost reduction by combined carotid endarterectomy and coronary artery bypass grafting. J Thorac Cardiovasc Surg 1996;111:1185 93. 17. Jones EL, Craver JM, Michalik RA, et al. Combined carotid and coronary operations: when are they necessary? J Thorac Cardiovasc Surg 1984;87:7 16. 18. Coyle KA, Gray BC, Smith RB, et al. Morbidity and mortality associated with carotid endarterectomy: effect of adjunctive coronary revascularization. Ann Vasc Surg 1995;9:21 7. 19. Kouchoukos NT, Daily BB, Wareing TH, Murphy SF. Hypothermic circulatory arrest for cerebral protection during combined carotid and cardiac surgery in patients with bilateral carotid artery disease. Ann Surg 1994;219:699 706. 20. Tuman KJ, McCarthy RJ, Najafi H, Ivankovich AD. Differential effects of advanced age on neurologic and cardiac risks of coronary artery operations. J Thorac Cardiovasc Surg 1992; 104:1510 7. 21. Schwartz LB, Bridgman AH, Kieffer RW, et al. Asymptomatic carotid artery stenosis and stroke in patients undergoing cardiopulmonary bypass. J Vasc Surg 1995;21:146 53. 22. Salisidis GC, Latter DA, Steinmetz OK, Blair JF, Graham AM. Carotid artery duplex scanning in preoperative assessment for coronary artery revascularization: the association between peripheral vascular disease, carotid artery stenosis, and stroke. J Vasc Surg 1995;21:154 62. 23. Berens ES, Kouchoukos NT, Murphy SF, Wareing TH. Preoperative carotid artery screening in elderly patients undergoing cardiac surgery. J Vasc Surg 1992;15:313 23. 24. Mickelborough LL, Walker PM, Takagi Y, Ohashi M, Ivanov J, Tamariz M. Risk factor for stroke in patients undergoing coronary artery bypass grafting. J Thorac Cardiovasc Surg 1996;112:1250 9. 25. D Agostino RS, Svensson LG, Neumann DJ, Balkhy HH, Williamson WA, Shahian DM. Screening carotid ultrasonography and risk factors for stroke in coronary artery surgery patients. Ann Thorac Surg 1996;62:1714 23. Appendix 1. Factors Tested as Univariate and Multivariate Predictors of Events Factor Hospital Mortality Postoperative Stroke Postoperative Stay Sex 1.000 1.000 0.872 Left ventricular function 1.000 0.640 0.119 Angina class 1.000 0.294 0.955 Hypertension 0.595 0.309 0.244 Prior coronary artery bypass grafting 0.298 0.398 0.352 Prior myocardial infarction 1.000 0.288 0.292 Prior carotid endarterectomy 1.000 0.284 0.905 Prior stroke 0.088 0.157 0.371 Transient ischemic attack 1.000 1.000 0.694 Smoking 1.000 0.566 0.122 Operating room priority 1.000 0.565 0.122 Internal mammary artery graft 1.000 1.000 0.045/0.050 a Pulmonary 0.228 0.008 0.001/0.001 a Diabetes 0.291 0.614 0.407 Peripheral vascular disease 0.007 0.181 0.966 Left main coronary artery disease 0.013 0.045 0.547 Carotid artery disease 0.551 1.000 0.054/0.064 a Stroke 0.009 Not tested 0.042 Creatinine level 0.002 0.002 0.07 Age 0.355 0.642 0.101 Cross-clamp time 0.874 0.760 0.468 Pump time 0.711 0.663 0.709 a Multivariate predictor.