Manual Coronary Endarterectomy with Saphenous Bypass: Experience with 263 Patients

Manual Coronary Endarterectomy with Saphenous Bypass: Experience with 263 Patients Eugene Wallsh, M.D., Andrew J. Franzone, M.D., Roy H. Clauss, M.D., Ciro Armellini, M.D., Felicien Steichen, M.D., and Simon H. Stertzer, M.D. I

ABSTRACT From January, 1972, until August, 1980, 271 manual coronary endarterectomies with bypass were performed in 263 patients. All patients underwent additional cardiac procedures simultaneously. The group contained 254 distal right and 17 left endarterectomies (including 8 double endarterectomies).

Clinical follow-up was 100°/~, operative mortality was 2.3% (6 out of 2631, and the rate of perioperative infarction was 4.9% (13 out of 263). Cineangiography was performed on 72 patients between 1 and 60 months after operation (mean, 15.4 months). Patency was 85% (61 out of 72).

Endarterectomy in a dominant right coronary artery could be planned electively. Left coronary endarterectomy was performed only when diffuse disease prevented standard bypass.

Coronary endarterectomy may be used to extend operability with excellent clinical results, low perioperative mortality, and high late patency. Care- ful attention to technical aspects of core removal and myocardial protection are necessary for consistent results.

Manual coronary endarterectomy can be used to supplement standard bypass graft technique in coronary arteries with diffuse atherosclerosis. This report documents the cumulative experience with this technique at Lenox Hill Hos- pital.

Materials and Methods From January, 1972, until August, 1980, 271 manual coronary endarterectomies with saphenous coronary- bypass were performed in

From the Departments of Surgery and Medicine, Lenox Hill Hospital, New York, NY. We thank Mr. Carl Manela for his technical assistance in the preparation of this manuscript. Presented at the Seventeenth Annual Meeting of The Soci- ety of Thoracic Surgeons, Jan 26-28,1981, Los Angeles, CA. Address reprint requests to Dr. Wallsh, 130 E 77th St, New York, NY 10021.

263 patients (238 men and 25 women). The age range was 35 to 74 years (mean, 58 years). There were 254 distal right and 17 left anterior descending coronary endarterectomies. Eight double endarterectomies were included. All patients simultaneously underwent additional cardiac procedures. Distal right coronary endarterectomies were performed on angiographically dominant right coronary arteries with severe obstructive disease at the crux of the vessel. The disease process frequently ex- tended into the distal branches of the right coronary artery.

Techniques and results of coronary endarterectomy with saphenous bypass have been described by several authors [l-91. Our own technique for manual endarterectomy with bypass has been modified since its original description [lo]. When the right coronary artery was completely obstructed proximally, the distal endarterectomy was performed on a nor- mothermic, beating heart. Cardiopulmonary bypass was carried out using arterial inflow to the ascending aorta, with a single cannula draining the right atrium. Ventricular venting was not used. Left atrial pressure was moni- tored continuously. The aVF lead was displayed on the electrocardiogram during the procedure. The acute margin of the heart was retracted ex- posing the crux of the right coronary vessel. A 1 cm incision was made about 1 cm from the bifurcation of the right coronary artery into its posterior descending coronary and atrioventricular groove branches. The incision was deepened to the atheromatous core. The outer linings of the coronary artery were teased from the core. Any circular muscle fibers ad- herent to the retained outer layers were scru- pulously removed to ensure a smooth lining. Interrupted sutures were placed circumferen- tially through the developed outer layers. Epicardium was included in each suture for maximum hemostasis.

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452 The Annals of Thoracic Surgery Vol 32 No 5 November 1981

The atheromatous core was mobilized proximally first. The superficial coronary layers were progressively separated from the core by a combination of steady traction on the core and countertraction on the outer coats using a blunt instrument. After approximately 2 cm of core had been mobilized proximally, the specimen was transected. The remaining proximal atheromatous material was permitted to retract. The distal specimen was then mobilized to the bifurcation of the posterior descending coronary and atrioventricular groove branches (Fig 1). The beating action of the heart against the steady traction on the core helped in separating the layers as distal dissection progressed. Each limb was removed separately. Excessive traction could easily result in fracture of the specimen. Retained distal fragments or highly obstructive skip lesions could result in incomplete endarterectomy, and could obstruct graft runoff and result in dissection with formation of a hematoma ad the endarterectomy site. Ex- amination of the extracted specimen usually confirmed complete removal of the core. The appearance of fine, translucent distal ends in&- cated core separation at a site of normal intima (Fig 2). However, if fracture of the endarterectomy specimen occurred or if atheromatous material could be palpated in the distal branches, an incision was made over the plaque. Then the residual material was mobilized and extracted from the branch vessel.

Fig I. Distal right coronary endarterectomy technique. The proximal core has been severed, and the distal specimen is being progressively extracted. Sutures are in place.

Fig 2 . Intact endarterectomy specimen demonstrating thin, tapering branch ends, which usually indicate cow- plete core extraction.

453 Wallsh et al: Manual Coronary Endarterectomy

The secondary arteriotomy was closed with fine interrupted sutures placed at the edges of the now widened arterial channel. A temporary Silastic shunt was used in the artery as a stent around which the sutures were placed [l l l . This shunt technique facilitated suture placement in the coronary vessel with the heart beating.

Retained plaque or skip lesions were removed prior to completion of the proximal bypass. This sequence usually avoided hematoma formation. Should hematoma occur, it might extend along the distal coronary branches and make secondary core extraction extremely awkward.

Following endarterectomy, a reversed segment of saphenous vein was sutured to the endarterectomy site with the previously placed interrupted sutures. The proximal aorta- saphenous vein anastomosis was constructed with a continuous suture within a partially occluding vascular clamp on an appropriate portion of the ascending aorta.

If S-T segment changes occurred in lead aVF during extraction of the atheromatous core, moderate systemic hypothermia was begun. In several instances of persistent electrocardiographic changes following core extraction, despite intravenous administration of nitroglyc- erin and moderate systemic cooling, arterial blood was perfused into the endarterectomized channel using a soft T-shaped plastic cannula. The S-T segment changes were rapidly reversed.

When the right coronary artery was not completely obstructed, retraction of the edge of the heart for adequate exposure might occlude the intrinsic blood flow in the right coronary artery. Interruption of this flow in a dominant right coronary artery has resulted in profound electrocardiographic changes and rapid infarction. When there was incomplete coronary occlusion, the cardiopulmonary bypass technique was al- tered to include the use of hypothermic cardioplegia. The endarterectomy technique was essentially the same.

Endarterectomy of the left anterior descending coronary vessel was rarely a planned procedure. In diffusely diseased vessels, all attempts were directed at bypassing to an angiographically patent portion of the vessel. However, two

situations necessitated endarterectomy. The first arose upon spontaneous separation of an atheromatous intima when wall integrity could not be reconstructed by appropriate suturing. The second involved a short area of total coronary obstruction interposed between two angiographically patent segments. Endarterec- tomy of this short segment permitted runoff into a wide vascular bed with a single graft. Cardioplegia technique was usually employed during the performance of endarterectomy of the anterior descending coronary artery. A longer-than-normal arteriotomy was performed to facilitate manipulation of the atheromatous core. The appropriate plane for dissection was usually identified easily. Gentle traction on the core with countertraction on the outer layers with a blunt instrument served to deliver the core both proximally and distally. Spontaneous fracture of a short specimen at an appropriate site usually occurred. However, multiple arteriotomies along the anterior descending coronary artery have been necessary to ensure adequate core removal. Following delivery of the core, the vein bypass was constructed to the arteriotomy site by means of continuous suture technique. Antiplatelet drugs or anticoagulants were not used routinely in this series of patients.

Results Clinical follow-up of the 263 patients was 100% either by office interview or letter to the patient or attending physician. Follow-up ranged from 5 to 96 months (mean, 54 months). The operative mortality was 2.3% (6 out of 263). Low cardiac output and myocardial infarction ac- counted for the deaths. Immediate graft failure with hematoma was evident in 1 patient. Perioperative myocardial infarction as indi- cated by new electrocardiographic Q waves or positive isoenzyme changes occurred in 4.9% (13 out of 263). Nine of these intraoperative infarctions occurred in the first 29 patients operated on in this series. During this period, elective electrical fibrillation was used during operation. The occurrence of a small Q wave in lead aVF during the procedure was not consis- tently associated d i th technical failure of the graft. Four of the patients who had new Q


waves were restudied and found to have patent grafts. In 2 of 11 patients in whom hematomas developed at the site of saphenous bypass endarterectomy, electrocardiographic changes developed consistent with myocardial damage. With modification of the endarterectomy technique as described, the incidence of local hematoma and regional electrocardiographic changes has markedly decreased. Hematomas have not occurred in the group of 17 patients undergoing endarterectomy of the anterior descending coronary artery.

Late presumed coronary deaths occurred in 1.9% (5 out of 263). Two late noncoronary deaths also occurred: one from sepsis and the other from hepatitis.

Postoperative catheterization for cineangiography was performed on 27% (72 out of 263) of patients between 1 and 60 months (mean, 15.4 months) after operation. This group consisted of 1 anterior descending and 71 right coronary artery endarterectomies. The overall patency was 85% (61 out of 72). The graft to the anterior descending coronary artery was closed.

Comment Endarterectomy with saphenous bypass is a useful adjunct in the treatment of diffuse coronary artery disease. Technically inoperable vessels or vessels with limited operability by angiographic appearance can be salvaged by this technique. Late patency may be enhanced by anastomosis to an atherosclerosis-free, grossly smooth vessel when compared with bypasses constructed in heavily diseased segments. More complete revascularization is possible with endarterectomy by wider distribution of the graft flow.

Elective coronary endarterectomy and saphenous coronary graft can usually be planned in the right coronary artery when an angiographically dominant vessel is completely obstructed proximally and shows retrograde filling of the distal branches through collateral circulation. Endarterectomy of the left anterior descending coronary artery is nonelective. The results are less predictable than in the right coronary artery. However, in some situations its use is unavoidable. Endarterectomies of diagonal and marginal branches were initially

evaluated and discontinued because of incon- sistent core extraction.

The segmental wall motion of the inferior surface of the left ventricle demonstrated by contrast ventriculography is not an absolute determinant of the feasibility or the success of distal right coronary endarterectomy with bypass. This finding is in contrast to another report [7]. Despite fibrosis in the inferior wall, restoration of blood flow in the distal branches of the right coronary artery may represent the source of major collaterals to the remaining circulation in patients with diffuse coronary artery disease.

Complete core removal is essential for success of the endarterectomy. Confirmation of complete extraction by examination of the distal branches of the atheromatous specimen can be deceiving. In the right coronary artery, palpa- tion of the distal vessels is especially important in disclosing either retained specimens or skip areas of plaque. Removal of these distal ob- structions is essential for consistent success of the procedure.

In a dominant, small right coronary artery, less than 2 to 3 mm in diameter, pliable walls of the core may not separate easily. Attempting extraction can leave a thin, porous wall result- ing in diffuse hematoma formation at the anastomosis and along the coronary branches. This can cause immediate failure of the endarterectomy and bypass graft, with regional infarction. In this series, hematoma formation occurred in 11 of 263 patients (4.2%) with severe diffuse atherosclerosis.

Local dissection of an atherosclerotic plaque at the site of saphenous coronary bypass in vessels in which endarterectomy has not been performed has been demonstrated to be one of the causes of graft failure [12]. Endarterectomy with bypass to vessels with heavily atherosclerotic walls seems to be a reasonable surgical alternative to simple bypass.

The incidence of perioperative infarction of 4.9% (13 out of 263) primarily reflects the nine instances that occurred within the first 29 patients undergoing operation in this series [lo]. Elective ventricular fibrillation was used with these patients. Subsequently, this technique has been discarded.


The operative mortality of 2.3% in these patients with severe diffuse coronary artery disease, as well as the late patency rate of 85% (61 out of 72) in the follow-up period, indicate an expanding role for coronary endarterectomy in the operative treatment of extensive coronary disease. Myocardial protection and careful attention to the technical aspects of core removal are essential.

Improvement in the operative status of the atherosclerotic vessel wall as well as the possi- bility of vein grafting to angiographically inoperable vessels has been a consistent observa- tion in manual coronary endarterectomy with bypass.

References 1.

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Robinson G , Kaplitt MJ, Philips P, Pate1 8: Com- plete surgical correction of the totally occluded and diffusely diseased right coronary artery. J Thorac Cardiovasc Surg 60:504, 1970 Absolon KB, Lewis EH, Bashour F: Simultaneous peripheral coronary endarterectomy and bypass graft in coronary artery obstruction. Surg Gyne- col Obstet 132:1083, 1971 Urschel HC Jr, Razzuk MA: Reconstruction of the left anterior descending coronary artery: proximal vein bypass and distal gas endarterectomy. JAMA 16:141, 1971 Urschel HC Jr, Razzuk MA, Wood RE, Paulson DL: Distal COz coronary artery endarterectomy and proximal vein bypass graft. Ann Thorac Surg 14:10, 1972 Dumanian AV, Giragos HG, Hadidian HA, et al: Endarterectomy of the branches of the left coronary artery in combination with an aorta-to- coronary artery reversed saphenous vein graft. Ann Thorac Surg 14:609, 1972 Groves LK, Loop FD, Silver GM: Endarterectomy as a supplement to coronary artery-saphenous vein bypass surgery. J Thorac Cardiovasc Surg 64:514, 1972 Cheanvechai C, Groves LK, Reyes EA, et al: Manual coronary endarterectomy: clinical experience in 315 patients. J Thorac Cardiovasc Surg 70:524, 1975 - Hochberg MS, Merrill WH, Michaelis LL, McIn- tosh CL: Results of combined coronary endarterectomy and coronary bypass for diffuse coronary artery disease. J Thorac Cardiovasc Surg 75:38, 1978 Morton BC, Beanlands DS, Chambers RS, et al: Fate of the graft and native vessel following endarterectomy of the left anterior descending coronary artery. Can J Surg 22:142, 1979 Wallsh E, Weinstein G, Franzone AJ, Stertzer

SH: The use of distal right coronary endarterectomy and saphenous coronary bypass to decrease total grafts and extend operability in patients with coronary artery disease. In Norman JC (ed): Coronary Artery Medicine and Surgery: Con- cepts and Controversies. New York, Appleton- Century-Crofts, 1975, chap 68

11. Franzone AJ, Wallsh E, Stertzer SH, et al: Re- duced incidence of intraoperative myocardial infarction during coronary bypass surgery with use of intracoronary shunt technique. Am J Car- diol 39:1017, 1977

12. Griffith LSC, Bulkley BH, Hutchins GM, Brawley RK: Occlusive changes at the coronary artery- bypass graft anastomosis: morphologic study of 95 grafts. J Thorac Cardiovasc Surg 73:668, 1977

Discussion DR. HAROLD c. URSCHEL, JR. (Dallas, TX): I congratulate Dr. Wallsh on his presentation. These good results with the mechanical endarterectomy are limited to the right coronary artery primarily. Although a few of his patients were restudied in five years, the average was 15 months. I think we still have to consider this short-term follow-up, but the close to 90% patency is certainly in line with other series that have been presented, including ours. I do not believe that it is better to do an endarterectomy on a beating heart, and prefer a quiet, still heart on which to perform the endarterectomy and the subsequent vein graft.

Historically, endarterectomy was used to attack coronary artery disease before the vein graft, and most of the early procedures were just endarterectomies alone with closure of the arteriotomy. Because we had a very high occlusion rate in the late 1960s, we changed our technique by closing the arteriotomy with a high-flow vein graft and combining the mechanical endarterectomy with administration of car- bon dioxide so we could get a more complete distal endarterectomy, particularly in the left anterior descending coronary artery.

We now have done about 223 endarterectomies, the majority in the left anterior descending coronary artery, and the early patency has been around 90%. We do not know what the late patency will be. How- ever, in general, when occlusion occurs in the endarterectomized vessel on restudy, there is usually much better collateral filling into this area than before the operation. This knowledge plus the fact that these vessels would not be revascularized with- out endarterectomy probably make endarterectomy worth doing in certain instances. It may be the only way to help improve ventricular function in patients with severe diabetes or abnormal blood lipids,

The authors’ poor early results show improvement with experience. Catastrophe occurs, however, when we open a diseased vessel, separate the intima, and


do an incomplete endarterectomy. Therefore, regardless of our philosophy of elective endarterectomy, whether we do it frequently or infrequently, I think we should all be proficient with this technique and be able to perform a complete, expeditious endarterectomy if we damage a vessel we intended to graft initially.

DR. PABLO PEDRAZA (Milwaukee, WI): I congratulate Dr. Wallsh on his presentation of an excellent paper. We have performed coronary endarterectomy with increasing frequency over the past ten years. My associate, Dr. Johnson, and I have done single and multiple endarterectomies in about 30% of patients operated on in the last few years. Coronary endarterectomy is our treatment of choice for severe, ad- vanced coronary disease. In most cases, it is the only practical method of revascularizing the septum.

In the past, we have demonstrated normal flow re- sponse of endarterectomized vessels with xenon washout studies. I will review our short-term patency. From March, 1978, through July, 1980, 507 of 984 (52%) patients underwent recatheterization before discharge; 167 of 507 (33%) had at least one coronary endarterectomy. Overall patency of grafts to endarterectomized arteries was 217 of 242 (89.7%) compared with 429 of 476 (90.1%) for conventional saphenous vein grafts in the same patients. Patency was essentially the same regardless of which major coronary system was endarterectomized.

For myocardial protection we rely on intermittent ischemic arrest at 30 to 34°C systemic. Rates of perioperative infarction and mortality have been similar to those reported today. We believe that coronary endarterectomy is here to stay.

DR. FRED E. VERMEULEN (Utrecht, The Netherlands): I also compliment the authors for their fine study and especially for their excellent results. Some years ago we did an analysis of 240 patients with 264 endarterectomies. The data that came out of that study were somewhat at variance with those shown today.

Our rate of infarction after operation was higher, being 11% if we include hospital mortality or 8% if we consider only the survivors, and it appeared to be related to the preoperative status of the vessels. In 116 occluded vessels, eight infarctions occurred (7%), half of them not related to the area of the endarterectomy. However, for the endarterectomies done on 137 stenotic vessels, the infarction rate was much higher-15°/o-with 16 of the 20 infarctions related to the area of the endarterectomy. Could the low postoperative infarction rate in the authors' series be related to the fact that they mainly performed endarterectomies in totally occluded vessels?

Regarding the patency rate, we noted that there was no relationship in our series with the preoperative status of the vessel. That means that endarterec-

tomies were followed by a 25% graft occlusion rate both in those that were done for occluded vessels and in those for stenotic vessels. However, in contradic- tion to what the authors showed, we noticed an in- creased occlusion rate from 19% overall to 35% if the endarterectomy was done in an area where there was already an infarction. So we disagree with the authors on this paint, as they did not detect any influ- ence of the local status of the ventricle on the graft patency.

We studied 105 patients by postoperative angiography, and compared the patency in grafts leading to endarterectomized vessels versus grafts leading to nonendarterectcimized vessels in the same patients (acting as their own control) and analyzed the quality of the runoff. We subdivided them into three groups: early controls (18 endarterectomies and 25 controls), an intermediate group after a mean of 7 months (64 endarterectomies and 49 controls), and a long-term group with a rnean of 21 months (62 endarterectomies and 75 controls). We found that the overall patency rate, even after almost two years, is still ac- ceptable: 74% after endarterectomy versus 81% in the control grafts. However, it was striking to us that at any time, about half of the patent grafts to endarterectomized vessels did show a clearly residual or recurrent stenosis that, in our definition, was in ex- cess of 50% of the lumen. I wonder if the authors analyzed the quality of the runoff in their postoperative angiography series.

DR. GEORGE E. REED (Valhalla, NY): Dr. Wallsh very kindly asked me to review his manuscript, and I was delighted to have this preview. This beautifully presented paper is a landmark, which I think should lay to rest any question about the appropriateness of right coronary endarterectomy or the effectiveness of manual endarterectomy. The 85% patency rate found in a group of patients who were restudied primarily because of chest complaints shows that this procedure can be the equal of the conventional bypass operation.

When one considers that the group who had repeat angiography was at a higher risk initially for graft closure and additionally that all had chest complaints, it suggests that the results are probably even more laudatory than we realize.

I was, however, disappointed to find that only 1 of the 17 left coronary endarterectomies was restudied and that this graft was closed. It is upon these left- sided procedures that I would like to elaborate.

During the past year, encouraged by having seen several late studies on patients who had right coronary endarterectomy and comforted by the safety af- forded by cardioplegia, and then confronted by an inoperable left anterior descending coronary artery in a very young man, we began doing left-sided endarterectomies at the Westchester Medical Center. A


total of 175 endarterectomies were performed in the last year in 132 patients. Of these, 63 were of the left anterior descending coronary or circumflex coronary artery. Our early clinical results corroborate the safety of this procedure as described by Dr. Wallsh. The only death in this group resulted from myocardial infarction, which occurred during repeat coronary angiography two weeks after operation in a patient in whom all vessels were patent.

This is not a new operation. It has been well described, with minor variations, by many authors during the past ten years. What makes it more at- tractive now is the safety and precision that cardioplegia provides. The salient features should be re- emphasized. It is imperative that the distal vessel be meticulously cleared of the disease and that we realize that multiple, long arteriotomies are frequently necessary.

DR. WALLSH: I thank the discussants and am gratified to see the renewed interest in a very useful technique. I will attempt to answer some of the ques- tions brought up by Dr. Vermeulen, but have to base my answer partially on the fact that I did not hear any description of the surgical technique. I cannot explain why the rates of postoperative infarction and patency were different from our results.

However, I will comment on the angiographic appearance. Among the 72 patients studied, 8 were followed with multiple recatheterizations, not included as separate studies within the group. Some endarterectomies that we restudied were irregular in appearance, but during the period of restudy, they stayed open. I cannot explain this. Perhaps it is related to nonatherosclerotic narrowing that may not change with time.

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Manual Coronary Endarterectomy with Saphenous Bypass: Experience with 263 Patients