HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Sara J. Shumway Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Djalilian, A. R. Articles by Shumway, S. J. Search for Related Content PubMed PubMed Citation Articles by Djalilian, A. R. Articles by Shumway, S. J.

Ann Thorac Surg 1995;60:1749-1754
© 1995 The Society of Thoracic Surgeons

---

Original Articles: Cardiovascular

Adjunctive Coronary Endarterectomy: Improved Safety in Modern Cardiac Surgery

Division of Cardiovascular and Thoracic Surgery, University of Minnesota, Minneapolis, Minnesota

Accepted for publication August 5, 1995.

	Abstract

Top Footnotes Abstract Introduction Material and Methods Results Comment References

 
Background. Advances in cardiac surgery have led to an improved safety record for coronary endarterectomy.

Methods. We retrospectively reviewed the cases of 64 patients who underwent adjunctive coronary endarterectomy between August 1988 and February 1992. There were 44 men, and the mean age was 65 years. Forty-one patients (64%) had sustained a previous infarction. Overall, endarterectomy was performed on 76 vessels, and the right coronary system was involved in 46 (61%).

Results. The postoperative infarction rate was 5%. Incomplete occlusion (<90% stenosis) of the endarterectomized vessel significantly increased the risk of infarction (p < 0.05). There were two early deaths (3%). The mean follow-up was 46 months. Clinically, 91% of the survivors were angina free, and 80% had no symptoms of heart failure at the time of follow-up. Left ventricular function had improved in 36% of those restudied (5/14). A total of 17 recatheterizations were done at a mean interval of 19 months after operation. The endarterectomy graft patency rate was 80% (16/20) compared with 78% (28/36) for conventional grafts (p = not significant). The actuarial survival rates were 89% and 71% at 1 year and 5 years, respectively. A history of previous infarction was significantly associated with higher long-term mortality (p < 0.02).

Conclusions. Overall, these results demonstrate that in modern cardiac surgery, coronary endarterectomy is safer than previously thought and can be used effectively to achieve complete revascularization in selected patients.

	Introduction

Top Footnotes Abstract Introduction Material and Methods Results Comment References

 
Although coronary endarterectomy (CorEA) began as a treatment of atherosclerotic heart disease before coronary artery bypass grafting (CABG) became the gold standard, it continues to be a necessary adjunct to CABG in select patients [1]. After initial studies [2] demonstrated a significant associated risk of postoperative infarctions, adjunctive endarterectomies have been performed sparingly by most surgeons. However, advances in cardiac surgery, along with better patient selection, have led to the improved safety and efficacy of this procedure [3–6]. This has prompted some to call for a resurgence of CorEA especially in the current patient population that has more complex coronary pathology [6]. Here we reported our recent experience with this procedure to examine its safety and efficacy in modern cardiac surgery.

	Material and Methods

Top Footnotes Abstract Introduction Material and Methods Results Comment References

 
Patient Population
Between August 1988 and February 1992, 64 patients underwent CorEA in conjunction with CABG by one of us (S.J.S.) at the University of Minnesota. This constitutes 10% of all patients who had CABG during this period. There were 44 men and 20 women with an average age of 65 years (range, 35 to 83 years). The indications for operation were unstable angina in 72% and postinfarction ischemia or cardiac failure in 28% of the patients. The mean number of diseased vessels per patient was 2.8. The mean ejection fraction was 0.47 (range, 0.22 to 0.74). Forty-one patients (64%) had sustained a previous myocardial infarction (MI) (Table 1).

The electrocardiographic criteria for defining postoperative MI included new Q waves, persistent intraventricular conduction defects, or loss of R wave progression across the chest leads. Creatine kinase levels were not routinely determined in every patient, but an MB fraction greater than 10% was considered highly suggestive of an infarction.

Postoperatively, all patients were given aspirin (325 mg/d) indefinitely. Anticoagulation with heparin sodium was started 6 hours postoperatively in all patients with a left-sided endarterectomy. These patients were switched to warfarin sodium after 3 to 4 days and continued to maintain an international normalized ratio between 1.5 and 2.

Statistical Methods
Kaplan-Meier survival analysis was used to calculate actuarial survival rates. A log-rank test was used to compare the survival rates of the different subgroups. Categoric data were compared using Pearson's ² or Fisher's exact test. A p value of less than 0.05 was considered significant.

	Results

Top Footnotes Abstract Introduction Material and Methods Results Comment References

 
Early
Postoperative MIs occurred in 3 patients (5%), one of which was fatal. The fatal MI occurred on the first postoperative day in a 69-year-old woman who had undergone endarterectomy of the right coronary artery (RCA). Postmortem examination revealed a 3-cm dissection in the left internal mammary artery, which was grafted to the left anterior descending coronary artery (LAD), and a large posterior infarct. A 60% to 70% stenosis was noted in the distal RCA beyond the endarterectomy site, but no thrombi or intimal flaps were seen. The other nonfatal infarctions were detected either by electrocardiograms or by enzymes. One was a lateral MI in a patient who had undergone endarterectomy of the LAD and the obtuse marginal artery, and the other was a mild anterior MI in a patient who had had endarterectomy of the LAD. Univariate analysis revealed that incomplete occlusion (<90% stenosis) of the endarterectomized vessel was associated with more postoperative infarctions (p < 0.05).

The only other early death occurred 43 days after operation in a patient with an RCA endarterectomy and aortic valve replacement who could not be weaned from the ventilator and subsequently had development of respiratory failure and cardiac failure. Thus, the overall postoperative mortality rate was 3%. Altogether, 28 patients had one or more postoperative complications (Table 3). The mean hospital stay was 13 days.

View larger version (11K): [in this window] [in a new window]   Fig 1. . Actuarial survival after adjunctive coronary endarterectomy. The 1-year and 5-year survival rates were 89% and 71%, respectively.

The 17 repeat catheterizations were performed at an average interval of 19 months after operation (range, 1 to 54 months). The indications were angina in 76% and preoperative evaluation for a noncardiac operation in 24%. The endarterectomized vessels restudied included 15 RCAs and 5 LADs. The overall patency rate of grafts to endarterectomized vessels (endarterectomy graft) was 80%. The patency rate was 83% for grafts examined within the first postoperative year (average interval, 6 months) and 75% for those restudied more than 1 year after operation (average time, 37 months). All five of the LAD endarterectomy grafts were found to be patent. The patency rate for conventional grafts was 78%, which did not differ significantly from that of the endarterectomy grafts (Table 5).

View larger version (12K): [in this window] [in a new window]   Fig 2. . Cumulative survival after coronary endarterectomy for patients with previous myocardial infarction (light line) and for patients without history of infarction (heavy line). The difference is significant (p < 0.013).

Revascularization involved using the left internal mammary artery to bypass the LAD after endarterectomy of the LAD and the second diagonal, and three venous grafts to bypass the ramus intermedius, obtuse marginal, RCA, and right posterior descending artery after endarterectomy of the obtuse marginal, RCA, and right posterior descending coronary arteries. All five endarterectomies were performed because each arteriotomy had revealed plaques occluding the lumen with no site available for distal bypass grafting. Total cross-clamp time was 1 hour 48 minutes, and bypass time was 2 hours 45 minutes.

Postoperatively, the patient was anticoagulated and subsequently discharged home on the eleventh day without complications. At follow-up 5 years after operation, the patient was asymptomatic with good exercise tolerance and no evidence of heart failure. He had had no further infarctions.

	Comment

Top Footnotes Abstract Introduction Material and Methods Results Comment References

 
Postoperative infarctions after CorEA are the main reason for the increased morbidity and mortality. Infarctions can result from residual obstruction, intimal flaps, thrombosis, or atheroemboli. The reported postoperative MI rates vary widely from 5% to 25% with mortality rates in the range of 0% to 15% [3, 7–10]. The differences among these studies partly reflect their wide range of patient populations as well as the different criteria used for diagnosing postoperative infarctions. However, it also reflects the time frame of these studies with respect to the advances in cardiac surgery. In particular, there appears to be a trend toward lower infarction and mortality rates in the more recent studies [3–5]. Our observed 5% postoperative MI rate and 3% mortality rate are both consistent with these recent experiences. As expected, we had a higher incidence of infarctions in patients with a left-sided endarterectomy. This increased risk stems from the likelihood of blocking off small branches by a ``snowplow'' effect, thus making the RCA more anatomically favorable [2]. More important was the fact that in all 3 patients who sustained a postoperative infarction, the endarterectomized vessel was not completely occluded preoperatively. This further emphasized the importance of reserving endarterectomy for totally occluded vessels to minimize the risk of postoperative infarction.

Clinically, 91% of our survivors were angina free, and 80% had no evidence of heart failure at an average interval of 3 years after operation. Numerous reports have documented similar results, indicating that patients appear to benefit symptomatically from the more complete revascularization afforded by an endarterectomy [3, 4]. Objective tests revealed that left ventricular function had improved in 36% and declined in 36% of the patients who were restudied. This suggests a beneficial role for endarterectomy if one keeps in mind that most of these patients were symptomatic at the time of their study. Minale and associates [11] demonstrated in their patients that after an endarterectomy, local wall motion improved in 35% to 45% of previously hypokinetic or akinetic areas and declined in 24% of normally contracting areas. Thus, to maximize the benefit of an endarterectomy, it should be limited to myocardial areas with already impaired contractility.

Our angiographic results are consistent with the previously published rates for long-term graft patency after endarterectomy, which range from 38% to 100% [4, 12, 13]. The discrepancy among these studies reflects the wide variations in the patient populations and the differences in intervals and indications for postoperative catheterization. Most of our patients who were restudied had recurrent anginal symptoms. Nonetheless, our series did not demonstrate any significant difference in graft failure between endarterectomized and nonendarterectomized vessels. This was true in both the early and late results, which demonstrated a 75% endarterectomy graft patency rate at 3 years compared with 80% in conventional grafts. Although some studies have found long-term patency rates to be lower in endarterectomy grafts, other reports have not consistently shown this to be true [4, 9, 14]. The best predictor of long-term graft patency appears to be graft flow at the time of operation [9]. This underlines the importance of adequate endarterectomy and elimination of competitive flow during operation. On the other hand, with standard use of antithrombotic therapy after CABG, the long-term patency rate of all bypass grafts has improved significantly [15]. In addition to aspirin, we also routinely anticoagulate patients with a left-sided endarterectomy. We believe that this further reduces the risk of thrombosis in these high-risk vessels.

Our 5-year survival rate of 71% is low compared with the rates in other studies, which typically range from 80% to 90% [3, 4]. However, this reflects the high number of noncardiac deaths in our patients, with malignancy being the most common cause. A significant increase in long-term mortality was observed in patients with a history of previous MI. This indicates the more advanced nature of the disease process in these patients and thus, their less favorable long-term outcome. Because our data were limited in size and complicated by the noncardiac deaths, we could not demonstrate that other factors such as advanced age or impaired ventricular function adversely affected long-term survival; others, [3, 4], however, have shown these to be significant factors. The outcome of our patient with the quintuple CorEA illustrates that despite the increased risk, multiple-vessel endarterectomies can be done safely with good long-term results.

Overall, our results reinforce those in recent reports [3–6] indicating that in the modern era of open heart surgery, adjunctive CorEA carries a much lower risk. Although improved surgical technique and better patient selection have contributed, it is mainly the improvements in CABG safety that account for this change. Superior myocardial protection, use of antithrombotic therapy, standard grafting with the internal mammary artery, and the availability of ventricular assist devices have all led to a better postoperative outcome [16]. At the same time, there has been a dramatic change in the patient population referred for CABG. An increasing number of patients are elderly, female, or diabetic and are seen at more advanced stages with diffuse distal coronary disease. In these situations, adequate revascularization is often not possible by standard CABG alone. By making ungraftable vessels suitable for bypass, an adjunctive CorEA allows the patient to achieve the long-term clinical benefits of conventional bypass grafting, namely, symptomatic relief and prolonged survival. Although, for ethical reasons, no controlled randomized studies have been done to prove this, the numerous retrospective studies in the literature provide overwhelming evidence of this long-term beneficial effect [3, 4, 7].

Despite the improved safety, the risks of CorEA should still be weighed against its potential benefits, especially for a left-sided vessel. We advocate limiting use of endarterectomy, whenever possible, to totally occluded vessels in patients in whom complete revascularization would otherwise be impossible.

Future research may further improve the results of adjunctive endarterectomy. Recently, Keogh and associates [17] reported their use of angioscopy to evaluate intravascular morphology after CorEA. Such technology could help perfect the surgical technique while providing a useful tool for those learning to perform endarterectomy. Some groups have examined the histopathology of endarterectomized coronary vessels [18]. They have demonstrated that restenosis in these vessels occurs mainly by a process of myointimal proliferation as opposed to recurrent atherosclerosis. Such hyperplastic responses are seen to various degrees after any type of injury to the vessel wall. For instance, the high restenosis rate observed after angioplasties is largely mediated by the same proliferative mechanism [19]. Many pharmacologic and molecular strategies have been tried to block this proliferation, but to date, none have been very successful clinically [19, 20]. Some researches have explored the use of irradiation and have demonstrated a reduced amount of intimal hyperplasia in animal models with irradiation after injury to the vessel wall [21]. Such techniques may potentially be applied successfully to further improve the long-term results of adjunctive CorEA.

Finally, although this study demonstrates the improved safety and beneficial value of CorEA in a relatively small group of patients, further large-scale outcome studies are indicated. As endovascular techniques such as angioplasty are used more frequently to treat early coronary lesions, surgical management of diffuse coronary disease will become an increasingly common and challenging problem, and therefore it becomes even more important to accurately determine the safety and efficacy of CorEA and to develop clear indications for its use.

	Footnotes

Top Footnotes Abstract Introduction Material and Methods Results Comment References

 
Address reprint requests to Dr Shumway, University of Minnesota, Box 207 UMHC, 420 Delaware St SE, Minneapolis, MN 55455.

	References

Top Footnotes Abstract Introduction Material and Methods Results Comment References

 

1. Bailey CP, May A, Lewman WM. Survival after coronary endarterectomy in man. JAMA 1957;164:641–6.
2. Effler DB, Groves LK, Sones FM Jr, Shirley EK. Endarterectomy in the treatment of coronary artery disease. J Thorac Cardiovasc Surg 1964;47:98–102.[Medline]
3. Livesay JJ, Cooley DA, Hallman GL, et al. Early and late results of coronary endarterectomy. Analysis of 3,369 patients. J Thorac Cardiovasc Surg 1986;92:649–60.[Abstract]
4. Brenowitz JB, Kayser KL, Johnson WD. Results of coronary endarterectomy and reconstruction. J Thorac Cardiovasc Surg 1988;95:1–10.[Abstract]
5. Christakis GT, Rao V, Fremes SE, Chen E, Naylor CD, Goldman BS. Does coronary endarterectomy adversely affect results of bypass surgery? J Cardiac Surg 1993;8:72–8.[Medline]
6. Loop FD. Resurgence of coronary artery endarterectomy. J Am Coll Cardiol 1988;11:712–3.[Medline]
7. Wallsh E, Franzone AJ, Clauss RH, Armellini C, Steichen F, Stertzer SH. Manual coronary endarterectomy with saphenous bypass: experience with 263 patients. Ann Thorac Surg 1981;32:451–7.[Abstract]
8. Wallsh E, Franzone AJ, Weinstein G, et al. Distal right coronary endarterectomy with saphenous coronary bypass for diffuse coronary disease. NY State J Med 1976;76:1827–33.[Medline]
9. Hochberg MS, Merrill WH, Michaelis LL, McIntosh CL. Results of combined coronary endarterectomy and coronary bypass for diffuse coronary disease. J Thorac Cardiovasc Surg 1978;75:38–44.[Medline]
10. Parsonnet V, Gilbert L, Gielchinsky I, Bhaktan EK. Endarterectomy of the left anterior descending and main-stem coronary arteries. A technique for reconstruction of inoperable arteries. Surgery 1976;80:662–73.[Medline]
11. Minale C, Nikol S, Zander M, Uebis R, Effert S, Messmer BJ. Controversial aspects of coronary endarterectomy. Ann Thorac Surg 1989;48:235–41.[Abstract]
12. Leatherman LL, Rochelle DG, Dawson JT, Terneny O, Hallman GL, Cooley DA. Coronary arteriography after coronary artery bypass (CAB) surgery. Circulation 1972;45,46(Suppl 2):181.
13. Kuijpers PJ, Lacquet LK, Skotnicki SH, et al. Distal gasendarterectomy and venous bypass in coronary artery surgery. J Cardiovasc Surg (Torino) 1974;15:158–62.[Medline]
14. Goldstein J, Cooper E, Saltups A, Boxall J. Angiographic assessment of graft patency after coronary endarterectomy. J Thorac Cardiovasc Surg 1991;102:539–45.[Abstract]
15. Chesebro JH. Effect of dipyridamole and aspirin on late vein-graft patency after coronary bypass operations. N Engl J Med 1984;310:209–14.[Abstract]
16. Edwards FH, Clark RE, Schwartz M. Coronary artery bypass grafting: The Society of Thoracic Surgeons National Database experience. Ann Thorac Surg 1994;57:12–9.[Abstract]
17. Keogh BE, Bidstrup BP, Taylor KM, Sapsford RN. Angioscopic evaluation of intravascular morphology after coronary endarterectomy. Ann Thorac Surg 1991;52:766–72.[Abstract]
18. Walley VM, Byard RW, Keon WJ. A study of the sequential morphologic changes after manual endarterectomy. J Thorac Cardiovasc Surg 1991;102:890–4.[Abstract]
19. Ip JH, Fuster V, Israel D, Badimon L, Badimon J, Chesebro JH. The role of platelets, thrombin, and hyperplasia in restenosis after coronary angioplasty. J Am Coll Cardiol 1991;16:77B–88B.
20. Epstein SE, Spier E, Unger EF, Guzman RJ, Finkel T. The basis of molecular strategies for treating coronary restenosis after angioplasty. J Am Coll Cardiol 1994;23:1278–88.[Abstract]
21. Shimotakahara S, Mayberg MR. Gamma irradiation inhibits neointimal hyperplasia in rats after arterial injury. Stroke 1994;25:424–8.[Abstract]

This article has been cited by other articles:

				B. Yilmazkaya, R. Circi, U. P. Circi, S. Gurkahraman, M. A. Yukselen, O. Z. Yondem, and O. Tasdemir Surgical Approaches in Left Anterior Descending Artery In-Stent Stenosis Ann. Thorac. Surg., May 1, 2008; 85(5): 1586 - 1590. [Abstract] [Full Text] [PDF]

				E. Gongora and T. M. Sundt III Myocardial Revascularization with Cardiopulmonary Bypass Card. Surg. Adult, January 1, 2008; 3(2008): 599 - 632. [Full Text]

				T. N. Ogus, M. Basaran, O. Selimoglu, T. Yildirim, H. Ogus, H. Ozcan, and M. H. Us Long-Term Results of the Left Anterior Descending Coronary Artery Reconstruction With Left Internal Thoracic Artery Ann. Thorac. Surg., February 1, 2007; 83(2): 496 - 501. [Abstract] [Full Text] [PDF]

				F. Nurozler, T. Kutlu, G. Kucuk, and C. Okten Off-Pump Coronary Endarterectomy in High-Risk Patients Asian Cardiovasc Thorac Ann, June 1, 2006; 14(3): 227 - 230. [Abstract] [Full Text] [PDF]

				H. A. Vohra, R. Kanwar, T. Khan, and W. R. Dimitri Early and late outcome after off-pump coronary artery bypass graft surgery with coronary endarterectomy: a single-center 10-year experience. Ann. Thorac. Surg., May 1, 2006; 81(5): 1691 - 1696. [Abstract] [Full Text] [PDF]

				S. Sirivella, I. Gielchinsky, and V. Parsonnet Results of Coronary Artery Endarterectomy and Coronary Artery Bypass Grafting for Diffuse Coronary Artery Disease Ann. Thorac. Surg., November 1, 2005; 80(5): 1738 - 1744. [Abstract] [Full Text] [PDF]

				R. Tiruvoipati, M. Loubani, M. Lencioni, S. Ghosh, P. W. Jones, and R. L. Patel Coronary Endarterectomy: Impact on Morbidity and Mortality When Combined With Coronary Artery Bypass Surgery Ann. Thorac. Surg., June 1, 2005; 79(6): 1999 - 2003. [Abstract] [Full Text] [PDF]

				H. Nishi, S. Miyamoto, S. Takanashi, H. Minamimura, T. Ishikawa, Y. Kato, and Y. Shimizu Optimal Method of Coronary Endarterectomy for Diffusely Diseased Coronary Arteries Ann. Thorac. Surg., March 1, 2005; 79(3): 846 - 852. [Abstract] [Full Text] [PDF]

				J. G. Byrne, A. N. Karavas, T. Gudbjartson, M. Leacche, J. D. Rawn, G. S. Couper, R. J. Rizzo, L. H. Cohn, and S. F. Aranki Left anterior descending coronary endarterectomy: Early and late results in 196 consecutive patients Ann. Thorac. Surg., September 1, 2004; 78(3): 867 - 873. [Abstract] [Full Text] [PDF]

				G. Marinelli, B. Chiappini, M. Di Eusanio, R. Di Bartolomeo, I. Caldarera, C. Marrozzini, A. Marzocchi, and A. Pierangeli Bypass grafting with coronary endarterectomy: Immediate and long-term results J. Thorac. Cardiovasc. Surg., September 1, 2002; 124(3): 553 - 560. [Abstract] [Full Text] [PDF]

				U. Hake and H. Oelert Outcome of coronary endarterectomy Ann. Thorac. Surg., March 1, 2000; 69(3): 977 - 977. [Full Text] [PDF]

				O. M. Shapira, G. Akopian, A. Hussain, M. Adelstein, H. L. Lazar, G. S. Aldea, and R. J. Shemin Improved clinical outcomes in patients undergoing coronary artery bypass grafting with coronary endarterectomy Ann. Thorac. Surg., December 1, 1999; 68(6): 2273 - 2278. [Abstract] [Full Text] [PDF]

				V. M. Walley, J.-F. Marquis, and W. J. Keon Successful surgical endarterectomy of a stented coronary artery Ann. Thorac. Surg., December 1, 1999; 68(6): 2346 - 2349. [Abstract] [Full Text] [PDF]

				T. M. Sundt III, C. J. Camillo, E. N. Mendeloff, H. B. Barner, and W. A. Gay Jr Reappraisal of coronary endarterectomy for the treatment of diffuse coronary artery disease Ann. Thorac. Surg., October 1, 1999; 68(4): 1272 - 1277. [Abstract] [Full Text] [PDF]

				G. Asimakopoulos, K. M. Taylor, and C. P. Ratnatunga Outcome of coronary endarterectomy: a case-control study Ann. Thorac. Surg., April 1, 1999; 67(4): 989 - 993. [Abstract] [Full Text] [PDF]

This Article Abstract Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Sara J. Shumway Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Djalilian, A. R. Articles by Shumway, S. J. Search for Related Content PubMed PubMed Citation Articles by Djalilian, A. R. Articles by Shumway, S. J.