James IV Article

The evolution of extracranial carotid artery surgery as seen by one surgeon over the past 40 years

J.E. Connolly
Department of Surgery, University of California, Irvine Medical Centre, 101 City Drive So. Orange CA. 92868-3298, USA

Correspondence to: J.E. Connolly, Department of Surgery, University of California, Irvine Medical Centre, 101 City Drive So. Orange CA. 92868-3298, USA Email: jeconnol@uci.edu 

Introduction Clinical trials Technical considerations Operative procedure Specific problems

Discussion Historical anecdotes Summary References

Keywords: Carotid, endarterectomy, eversion endarterectomy, external carotid endarterectomy, neck block 
Surg J R Coll Surg Edinb Irel., 1 October 2003, 249-258

Carotid endarterectomy is one of the most common vascular and neurosurgical operations. Controversies regarding its indications and safety have required several decades before general resolution, while its methodology is still debated. The first operations are described with particular emphasis on the epic successful procedure in 1954 by Eastcott and Rob. Early procedures were on patients with frank strokes with poor results. The development of carotid endarterectomy was slow because neurologists were unsure of its effectiveness and safety as the mortality and stroke results recorded by untrained surgeons were unacceptable. It was not until some 35 years after its introduction that randomised controlled trials, both in North America and Europe, defined its indications and demonstrated its benefits for both symptomatic and asymptomatic carotid stenosis. Clamping of the carotid vessels, required during endarterectomy, may result in various degrees of cerebral ischaemia. Methods to determine which patients need shunting are compared. The author has employed local neck block anesthesia since 1972, which is the only method that provides constant neurological assessment for selective shunting during carotid cross clamping. Evidence is presented showing that local anaesthesia also reduces complications of general anaesthesia, especially myocardial infarction. The technique of neck block, conventional endarterectomy and two varieties of eversion endarterectomy for carotid disease are described. Each of these techniques of endarterectomy is advantageous in certain circumstances, suggesting that vascular surgeons should ideally be proficient in each. Likewise, the management of early stroke after operation, stenotic or occluded external carotid the presence of retinal Hollenhorst plaques, and the totally occluded internal carotid, is presented. Finally, observations on some famous figures who suffered from cerebrovascular complications secondary to carotid disease and what effect it may have had on world history is discussed

 King James IV Lecture given at the Annual Congress of the Association of Surgeons of Great Britain and Ireland, Manchester on May 7, 2003

INTRODUCTION
Carotid endarterectomy is one of the most common vascular and neurosurgical operations. However, controversies regarding its indications and safety have required several decades before general resolution, while its methodology is still debated. Carotid, (karotide or karos) means to stupefy or plunge into deep sleep. In 1903, Chiari showed that by occluding the carotid in the neck manually, you could temporarily cause hemiplegia, aphasia or loss of consciousness.¹ It was not until 1927, when Moniz first introduced cerebral arteriography, that it was possible to obtain an accurate diagnosis of carotid disease.² It is interesting that Moniz received the Nobel Prize in 1949 for lobotomy, a procedure not nearly as significant, if at all, compared with arteriography.

The first successful surgical attempt to reverse transient cerebral ischaemia appears to have been performed by Loucks and associates at the Union Medical College in Peking, China in 1936.³ The patient was a Russian male suffering from intermittent transient right hemiplegia and aphasia. At exploration of the left neck, 10cc of thorium dioxide was injected into the left common carotid artery proximal to its bifurcation. A roentgenogram showed that none of the contrast entered the internal carotid artery. Accordingly, a small segment of the internal carotid was excised between ligatures. The patient was said to have improved after this procedure. The operation was called an arterectomy after Leriche and was designed to cure what was thought to be spasm of the internal carotid rather than arterial occlusive disease. The apparent effectiveness of the operation may well have been to remove a source of cerebral emboli. Although their publication appeared in the Archives of Surgery in 1938, it apparently did not stimulate any interest in direct carotid surgery while blockage or excision of the cervical sympathetic chain was practiced for cerebrovascular symptoms.

It wasn’t until 1951 that the neurologist Fischer noted on arteriography that the carotid vessels distal to the disease at the bifurcation were normal, thus, suggesting that local endarterectomy could be effective.⁴ He stated “It is even conceivable that some day vascular surgery will find a way to bypass the occluded portion of the artery during the period of ominous fleeting symptoms. Anastomosis of the external carotid artery or one of its branches with the internal carotid artery above the area of narrowing should be feasible”.⁵ Dos Santos in 1946 in Lisbon performed the first thromboendarterectomy of a femoral artery to restore flow to the leg, introducing a technique that subsequently was to be applied to the carotid vessels.⁶

The first successful reconstruction of a stenotic internal carotid artery was performed in 1951 by Carrera et al (1955).⁷ After reading Fischer’s article, they cut out the area of stenotic disease in the proximal internal carotid artery and then anastomosed the transected proximal external carotid end-to-end to the distal internal carotid artery in a male patient with stroke, but they did not report this operation until 1955. Strully et al (1953) attempted to remove the clot from a thrombosed internal carotid artery but could not obtain retrograde flow.⁸ They proceeded to ligate the vessel to avoid embolisation. DeBakey reported in 1975 that he had performed a carotid endarterectomy by the current conventional technique in 1953. ⁹ Eastcott et al (1954), at St. Mary’s Hospital in London, performed an operation on a 66-year-old woman who had suffered intermittent right hemiplegia and monocular blindness.¹⁰ An arteriogram was obtained which showed an internal carotid stenosis. He then recommended surgical correction under general body hypothermia of 28°C (Figure 1). It consisted of resection of the disease at the carotid bifurcation followed by end-to-end anastomosis of the common carotid to the distal internal carotid. Because it was the first published reconstruction for carotid stenosis in a patient with transient ischaemic attacks, it gave the greatest impetus to the development of carotid surgery. In 1956, Cooley et al described a patient whose head was cooled and had an external bypass to provide adequate circulation to the brain during cross clamping of the carotid artery for a successful localised thrombo-endarterectomy. Figure 2 is a picture of Cooley’s procedure showing the shunt with a needle on either end, and a transverse incision, which did not provide much exposure for the procedure. At that time, ultrasound did not exist and, besides listening for a carotid bruit, a gloved finger was placed in the posterior pharynx in an attempt to palpate the internal carotid artery.¹¹

The early operations for carotid stenosis (Figure 3), subsequently, were performed on patients with profound stroke and carried a high operative mortality.¹² The first carotid endarterectomy I performed was in 1962 in a patient with an acute stroke who survived the surgery but later died.

Figure 1: Operating room scene during the first reported arterial reconstruction. Back to camera is the surgeon, H.H.G. Eastcott. Observing surgeon on the right is Professor Charles Rob

Figure 2: External shunt around a stenotic internal carotid artery; note the small for the endarterectomy

Figure 3: Diagram of early operations for carotid stenosis

Wiley et al (1964) reported five patients who underwent carotid endarterectomy with acute stroke who all succumbed after surgery.¹³ Subsequently, it was found that if the operation was delayed for at least 14 days, the mortality in stroke patients fell appreciably.

Rob and Wheeler (1957) reported the results of the first 27 carotid procedures performed at St. Mary’s Hospital after the epic successful patient in 1954.14,15 Eleven had stenoses and 16 had occlusions. All were operated on under general body hypothermia, 12 by thromboendarterectomy and 15 with local resection and end-toend anastomosis. They concluded that endarterectomy was indicated in symptomatic patients with stenosis, while complete occlusions should be operated on only under exceptional circumstances.

Carotid arteriograms, initially, were performed by direct percutaneous neck puncture of the common carotid artery under general anesthesia.¹⁶ Later, Seldinger (1953), described a retrograde technique that simplified and made arteriography of the carotids much safer.¹⁷ Subsequently, duplex ultrasound has been shown to be an excellent non-invasive method of diagnosing carotid disease, although, not quite as definitive as arteriography.^18,19 Magnetic resonance and spiral angiography techniques also provide other methods to visualise carotid disease.

CLINICAL TRIALS
The development of carotid endarterectomy was slow as many untrained surgeons carried out the procedure. Easton and Sherman (1977) reported the results of carotid endarterectomy in two small community hospitals in Illinois, where the mortality rate was 6.6% and the peri-operative stroke rate 14.5%, for a total complications rate of 21.1%.²⁰ Such statistics did not support the general use of carotid endarterectomy and solidified the belief that many neurologists held about the danger of the procedure. It wasn’t until some years later that randomised controlled trials were carried out. The North American Symptomatic Carotid Endarterectomy Trial (NASCT) was a major prospective, randomised study of symptomatic carotid disease and the effect of carotid endarterectomy on it.²¹ Results of the study reported in 1991 clearly demonstrated the benefit of carotid endarterectomy in patients with recent hemispheric and retinal transient ischaemic attacks or nondisabling strokes and high grade (70-99%) ipsilateral carotid stenosis. It also showed that the two and a half year stroke rate after carotid endarterectomy was 9% versus 26% for patients treated medically. The European Carotid Study Trial (ECST) showed that surgery was highly beneficial for 70-90% stenosis and moderately beneficial for 50-69% stenosis, but was of little benefit with near occlusion.^22,23 The stroke rate was 2.8% for surgical patients, excluding a peri-operative morbidity and mortality rate of 7.5% versus 16.8% for those treated medically. The risks of surgery, however, were significantly outweighed by the later benefits. The risk of ipsilateral ischaemic stroke was an extra 2.8% for surgery patients versus 16.8% for controls - a six fold reduction by life-table analysis.

The Asymptomatic Carotid Atherosclerosis Study (ACAS) concluded that patients with asymptomatic carotid artery stenosis of 60% or greater in diameter and whose general health made them good candidates for elective surgery will have a reduced five year risk of ipsilateral stroke if carotid endarterectomy is performed with less than 3% peri-operative morbidity-mortality.²⁴

The Veterans Affairs Cooperative Symptomatic Carotid Endarterectomy Study (VAST), using a 50% stenosis rate as the cutoff, reported a carotid endarterectomy stroke rate of 7.7% after endarterectomy vs 19.4% with medical treatment.²⁵ At 70% stenosis, the stroke rate was 7.9%, as compared with 25%, in patients that were treated medically.

It is now generally accepted that 35-40% of medically treated patients with transient ischaemic attacks (TIAs) eventually have strokes. Eight to 10% progress to frank strokes if observed for five years, for an annual rate of 1.7% per year. Another goal of carotid endarterectomy is relief of symptoms. Thompson et al (1970) followed a group of patients for 13 years and found that 77% continued to be asymptomatic while 17% improved after operation.²⁶

Indications for carotid endarterectomy in patients with less than 50% stenosis and ulceration are still under investigation.

TECHNICAL CONSIDERATIONS
Clamping of the carotid vessels is necessary during endarterectomy, which may result in various degrees of cerebral ischaemia. Thus, most surgeons continue to believe that carotid shunting is necessary. The fact that some surgeons who do not use shunts, have reported low stroke-mortality rates of a few percent would indicate that the incidence of irreversible brain damage is very low with carotid clamping even when an awake patient becomes unconscious during clamping. Baker et al (1984), however, documented that complications, in the absence of a shunt, were increased if both a contralateral internal carotid occlusion and a stump pressure below 50 mm Hg were present.²⁷ The authors reported that this subset of patients had a 14% stroke rate. However, operating on awake patients, we have not found that the presence of a contralateral internal carotid occlusion alone routinely results in neurological change on carotid clamping. Neurological change or unconsciousness occurs in less than 10% of awake patients during cross clamping, and less than 3% of these patients suffer irreversible brain damage without shunts. Since we do not know who these few patients at risk are, most surgeons opt to either shunt all patients under general anesthesia or only selectively, if they can identify the patients at risk. The objection to routine shunting is twofold. First, the shunt may impede a thorough endarterectomy and, secondly, the shunt has its own set of possible complications which include: risks of embolisation of air, clot or atheroma, dissection, malposition, distal coiling, and inadequate flow due to manufacturing deficits.³⁰

Thus, selective shunting is the procedure of choice currently employed by most vascular and neurosurgeons, using electroencephalography, stump pressure or awake neurological testing under a neck block, to identify which patient needs shunting.

Electroencephalography: This is reliable with only an occasional false-negative but more commonly a significant number of false positives.^31-33 In addition, there are potential instrumentation problems, the need for a technician for interpretation in the operating room and added costs.

Stump pressure: proximal clamped internal carotid is probably the most commonly employed technique to gauge the need for a shunt. There has been great controversy, however, regarding the level of stump pressure that signifies safe collateral cerebral flow to allow carotid artery cross-clamping without the need for shunting. Originally, Moore and Hall (1969) advocated 25mg Hg while Hays et al (1972) later put the safe level at 50mg Hg.^34,35 We evaluated these pressure levels by comparing them with awake neurological examination while cross-clamping the carotids under regional neck block in 125 consecutive patients undergoing carotid endarterectomy.³⁶ There were no deaths and three temporary neurological deficits in this series.³⁷ In group I, cross-clamping in 101 cases produced no neurological changes with stump pressure of between 20-90mg Hg. Group II consisted of 24 patients who lost consciousness on clamping with stump pressures ranging from 15-85mm Hg. We shunted the group that lost consciousness on cross clamping. This study demonstrated that some patients did not tolerate cross-clamping, even with stump pressures of 50mg Hg, while others with pressures below 50mg Hg did not show any evidence of cerebral ischaemia and would have unnecessarily been shunted by relying on stump pressure measurements. Our conclusion was that stump pressure is an unreliable absolute guide for selective shunting during carotid endarterectomy. Judging from the results of this study and that of others, if stump pressure is chosen as a guide to shunting, a level of 50mg Hg or higher is advisable.³⁵

Awake local neck block: Once we realised that stump pressure was an unreliable guide to shunting under general anesthesia, and because we believed in the value of selective shunting, in 1972 we adopted the awake operation under local neck block.^38-42 We employed this as the only method that provides reliable information about which few patients require selective shunting during carotid cross clamping. It should be remembered that in the presence of neurological change with carotid cross-clamping, immediately or during operation, there is no need for hurried shunt insertion. If there were no other collaterals to the brain other than the clamped carotids, which is not the case, one still has up to eight minutes before irreversible brain damage occurs.⁴³ One reason why the non-shunters have reported small incidences of stroke may be because they have performed their operations very rapidly with shorter cross-clamping times. Also, we soon became aware of the cardiac advantage of avoiding general anaesthesia for carotid endarterectomy. Others also have noted that operation under local neck block not only allows accurate intra-operative evaluation of neurologic status but also is accompanied by less peri-operative haemodynamic instability than during general anaesthesia, with resultant fewer major cardiac events.^44-47 Operation under local anaesthesia has been particularly applicable to high risk patients which include those with ejection fractions below 30%, poor respiratory function, contralateral carotid occlusion or high cervical lesions. Operative deaths from carotid endarterectomy are primarily due to cardiac rather than neurologic causes. Love and Hollyoak (2000) compared a large series of carotid endarterectomies performed under general versus local anaesthesia and found that the stroke rate and death in the local group was zero, compared with a 4.5% rate of stroke/ death in the cases performed under general anaesthesia.⁴⁸ Their conclusion was that local anaesthesia significantly reduces operative complications, especially myocardial infarction.

OPERATIVE PROCEDURE

Neck Block
Ideally, before arriving in the operating room, the patient is premedicated with 1-2mg of Versed and 1-2cc of fentanyl citrate. This results in a relaxed but awake patient. Originally, we used 1% lidocaine injected as we proceeded with the operation. Now an anaesthesiologist performs a superficial and deep cervical block, blocking the second, third and fourth cervical nerves at the transverse processes with 6 to 7cc of Carbocaine^® and 10cc of Marcaine^® for the superficial block. With a successful block, only additional infiltration of the carotid sheath and the carotid sinus area is made by the surgeon. A very important step of the awake technique is positioning a Mayo stand over the patient’s head so that no drapes touch the patient’s head or face (Figure 4). It is mandatory to select an anaesthesiologist who is interested in the technique and also monitors the patient carefully during surgery, employing an agent such as Fentanyl to keep the patient comfortable but awake so that the neurological status can be continuously monitored. Should a block be inadequate, local lidocaine is injected as needed by the surgeon. With an experienced team it is unusual that general anesthesia is required.

Conventional Endarterectomy³⁸
We start with a limited incision along the upper anterior sternocleidomastoid muscle until the carotid bifurcation is located, which is usually high in the neck. Once it is located, additional exposure cephalad or distal can be made; thus a long neck incision should never be necessary. While dissecting and circling the carotid vessels, care must be taken not to manipulate the area of disease in order to avoid embolisation. Before clamping of vessels, heparin is administered by the anaesthesiologist. During cross clamping of the common carotid, the tip of the clamp should not include the vagus nerve lest a recurrent nerve injury be caused. Any neurological change in the patient usually is noted within a minute of cross clamping. However, these changes may rarely develop during the operation. Whenever either occurs, a shunt is placed, but only after the distal portion of the endarterectomy has first been performed. There is no need to hurry the shunt placement as irreversible neurological damage does not occur until eight or more minutes of occlusion, even with contralateral carotid occlusion. Patching is an option, most importantly in females and with small carotid vessels. Either the proximal saphenous vein or various prosthetic materials have been shown to be equally effective patch material. Saphenous veins obtained from the ankle can rupture on occasions and, therefore, should be avoided as a patch. Neck infections with prosthetic material are rare because of the high vascularity of the area. There are a few long-term prospective reports on the results of managing asymptomatic recurrent stenosis expectantly.^49-52

Some investigators report that the majority of recurrent lesions will remain asymptomatic for years as most are not severely stenotic and are smooth, homogeneous and unlikely to undergo necrosis or ulceration. Ultrasound at endarterectomy completion can be helpful to document any major abnormalities. Bilateral operations should be staged at least three weeks apart.⁵³

Eversion Endarterectomy
This technique was first described by DeBakey in 1958 and subsequently popularised by Etheridge in 1970.^54,55 A variation was introduced by Kasprzak and Raithel in 1989, which has gradually become more popular in recent years.^56-59 Both methods employ transverse incisions which avoid carotid narrowing on closure and, thus, the need for carotid patching. The same mortality and morbidity is seen with either standard endarterectomy or the two eversion techniques, but there is definitely a lower restenosis rate with the eversion technique. Also, the operative time is less with both eversion techniques. Etheredge’s original operation was performed with a transverse incision just proximal to the carotid bifurcation, followed by everting the periadventitial tissue of both of the internal and external carotids, exposing and removing their disease cores (Figure 5). Likewise, the adventitial tissue of the common carotid is everted, allowing its diseased core to be transected. Finally, the periadventitial tissue of both ends are returned to their normal positions and re-anastomosed.

In the second eversion variation, the internal carotid artery is obliquely transected at its common carotid base, following which its adventitial tissue is everted proximally to beyond the end point of the disease, and the diseased portion is discarded (Figure 6). One also must be certain that the proximal transected common carotid and the external carotid are adequately endarterectomised before the internal carotid adventitial tissue is sewn back to its original position on the common carotid. To thoroughly endarterectomise the common carotid, it is sometimes necessary to make a longitudinal incision in it and use the elongated internal carotid adventitial tissue as a patch over it. Eversion endarterectomy is particularly advantageous for a redundant internal carotid as it can be readily shortened by the technique. This second variation allows removal of high lying internal carotid disease, whereas Etheridge’s original technique, although simpler, is suitable only for disease localised to the carotid bulb and proximal internal carotid. The decision of which technique to employ can be made at neck exploration. Although possible, neither eversion procedures are easy to shunt. Once carotid clamping has been tested for the need for a shunt, one can then determine whether to employ a conventional endarterectomy incision or one of the eversion techniques.

Figure 4 Top: The Mayo stand is positioned slightly over the patient’s face. The chin is taped to remind the patient not to turn the head; note nasal oxygen prongs. Bottom: Initial wound towels shown fastened to the Mayo stand with tape, thus, keeping the drapes off the face of the awake patient

Figure 5: Diagram of the Etheredge eversion endarterectomy. Common carotid divided just below bifurcation. The peri-adventitial tissue of both the external and internal carotids is everted until good feathering of the plaque and media fibres are ensured for their removal. A similar eversion of 2cm of the common carotid is also carried out and the disease excised. The reverted peri-adventitial tissue of the divided common carotid is then reanastomosed

Figure 6: Diagram of the Kasprzak-Raithel eversion endarterectomy. The internal carotid artery is cut obliquely at its common carotid base, after which the periadventitial tissue plane is located and is everted proximally until the plaque is feathered and removed. Next, the bulb and external carotid disease is removed from the open common carotid incision. The reverted internal carotid is anastomosed to the common carotid opening

SPECIFIC PROBLEMS

Management Of Early Stroke After Carotid Endarterectomy
The management of early neurological changes after carotid endarterectomy has been controversial. This problem presents when a patient is neurologically intact at the end of the operation and hours later develops neurological changes. We found that if time is spent trying to demonstrate the endarterectomy site, one will be unlikely to reverse the neurological changes. However, in those patients where we were able to take the patient back immediately to theatre and under local anaesthesia, open the carotid vessel, remove any clot and put in a temporary shunt within one hour of onset of the new neurological event, reversal of the changes were successful.^60-63

Figure 7: Collateral circulation between external and internal carotid arteries which is of particular importance when the internal carotid is occluded. Opening a stenotic external carotid can enhance cerebral blood flow

Figure 8: Common carotid-external carotid shunting leaving the internal carotid unobstructed for accurate endarterectomy 

Hollenhorst Plaques
Ophthalmologists, while performing routine fundoscopic examinations, may note atheromatous plaque material in retinal arteries, which may pass through the circulation or may lodge at bifurcations, causing permanent visual defects. If they are detected, sometimes by just massaging the eye, the atheromatous material may pass. These plaques, called Hollenhorst plaques, can alert the ophthalmologist to atheromatous disease of the proximal internal carotid artery, leading to investigations and indications for carotid endarterectomy. We have seen a number of patients with retinal emboli with minimal or no visual symptoms and without other neurological signs or symptoms.⁶⁴ The presence of these cholesterol retinal emboli has been an indication at our institution for an arteriogram followed by carotid endarterectomy if stenotic or ulcerating disease is found. Likewise, other fundoscopic abnormalities, including central and branch artery occlusion, ischaemic optic neuropathy, rubeosis iritis, neurovascular glaucoma, venous stasis, retinopathy and asymmetry of diabetic or hypertensive retinopathy are potentially valuable in identifying patients for further evaluation and treatment.⁶⁵

The Stenotic or Occluded External Carotid
Many surgeons do not pay adequate attention to endarterectomising the external carotid artery during carotid endarterectomy. However, if a symptomatic patient has an occluded internal carotid that cannot be opened, and there is significant narrowing or stenosis of the proximal external carotid, we have found that the cerebral circulation can be significantly increased by performing an external carotid endarterectomy.⁶⁶ Figure 7 is a diagram showing the various vessels connecting the external and the internal carotid arteries intracranially, particularly through the vessels of the eye. As much as 40% of the normal internal carotid blood flow can pass through the distal branches of the external carotid to the intracranial branches of the internal carotid. Another use of the external carotid is in carotid shunting. Rather than insert the distal end of the shunt into the internal carotid, it can be placed in the external carotid artery (Figure 8).⁶⁷ It can raise the stump pressure an average of 20%, which may increase a stump pressure to 50mm Hg and in turn, return consciousness to an awake patient who became unconscious on carotid clamping. The advantage of this shunt placement is that it does not interfere with the creation of the end point of the endarterectomy of the internal carotid artery.

The Totally Occluded Internal Carotid
With acute and subacute internal carotid occlusion, arteriography and computerised tomography of the head should be performed. In the absence of haemorrhagic cerebral infarction and overt signs of major stroke, one-third of occluded arteries can be successfully opened.⁶⁷ In the two-thirds of patients that cannot be opened, consideration should be made to perform an external carotid endarterectomy if stenosis is present. This can provide additional cerebral circulation.

DISCUSSION
In many series throughout the world, including ours, the combined peri-operative mortality and morbidity of carotid endarterectomy have been reported to be as low as 2-3%, even in patients with neurological symptoms.^37,57,69 We do not yet know whether eversion endarterectomy will replace conventional carotid endarterectomy and patching. It would seem that both conventional endarterectomy and eversion endarterectomy should become part of every vascular surgeon’s expertise, allowing a choice depending upon the particular circumstances in each case. For instance, if an operation performed under a neck block shows that with carotid clamping there is no neurological change, indicating no need for a shunt, then a rapid eversion technique might be preferable, especially if a long internal carotid needs shortening. On the other hand, if a shunt is necessary, a conventional technique would be more appropriate. Non-invasive diagnostic tests are likely to replace the angiogram as they are becoming more accurate, already replacing angiography when the clinical findings fit those of the duplex results. In our practice, patients with non-hemispheric symptoms or those accompanied by subclavian steal or equivocal duplex studies are submitted to arteriography.

Following careful assessment during the past 40 years, the vascular surgery community has shown that cardiac endarterectomy is a safe, durable and effective treatment for symptomatic and asymptomatic carotid stenosis. It is the author’s experience that for those who believe in shunting during carotid endarterectomy, the awake neurological assessment is the only absolute guide to both identify the need for, and minimise the use of, a shunt. Likewise, perhaps an even greater advantage of the awake technique is its value in eliminating haemodynamic instability and, in turn, lowering cardiac morbidity and mortality.

HISTORICAL ANECDOTES
It is interesting to note observations on some of the famous individuals that died of cerebrovascular disease.^70,71 Is it possible that Marshall von Hindenburg, in a demented condition from carotid artery disease, allowed Hitler to form a cabinet in 1933. If von Hindenburg hadn’t been suffering from carotid disease, Hitler may not have been in a position to form his cabinet. Lenin had TIAs and subsequently suffered a right hemiplegia and died of a stroke in 1924. President Franklin Roosevelt in 1943 had multiple TIAs followed by a stroke and death in 1945. Of course his physicians did not yet know about extra-cranial carotid disease or endarterectomy at that time. Nixon had a massive stroke in 1994 and died of the stroke. Had he ever been examined for carotid artery disease? Mayor Daley of Chicago had TIA attacks, which led to arteriography showing significant carotid disease. Javid performed a carotid endarterectomy successfully on him in 1974 and he lived for many years thereafter. The carotid surgery pioneer Rob suffered TIAs, followed by arteriography and successful carotid endarterectomy at age 81, ultimately dying seven years later of a massive myocardial infarction, free of cerebral vascular symptoms!

SUMMARY
Many lessons have been learned about the indications and methodology of carotid endarterectomy over the 40 years since this author’s first operation. It is now clear that, in the hands of experienced surgeons, carotid endarterectomy is a simple, safe procedure that reduces the incidence of stroke and its sequelae.

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Copyright: 19 June 2003