Myocardial infarction following carotid endarterectomy: a review of 683 operations.

In a series of 683 consecutive carotid endarterectomies, there were 16 postoperative myocardial infarctions which resulted in five deaths. Of 399 operations on patients with no previous history of heart disease, there were only two myocardial infarctions (0.5%). Two hundred and eighty-four operations were performed on patients with heart disease, and vasopressors were administered in 135 of these procedures. For these patients the risk of myocardial infarction increased from 2.0% to 8.1% with the use of vasopressors (P less than 0.001). The management of the patient with stable heart disease undergoing carotid endarterectomy is discussed.

Comparison of results of bilateral and unilateral carotid endarterectomy five years after surgery.

Consecutive patients who successfully underwent carotid endarterectomy (C) between 1970 and 1975 were followed during a 5-year period (mean follow-up 4.3 years). The patients were divided into three groups. Group I comprised 146 patients who had unilateral CE with a patent, nonstenotic contralateral carotid artery. Group II included 45 patients who underwent unilateral CE but whose contralateral internal carotid artery was found to be totally occluded. Group III consisted of 86 patients who underwent bilateral CE. There was no significant difference between the groups with respect to age, sex, neurologic status, or associated diseases, and all were maintained on antiplatelet medications for surgery. During the follow-up period a total of 22 of the 277 patients had a new hemispheric stroke; four others became comatose and died, presumably of stroke. Among the group I patients, 17 had new strokes, only six of which involved the hemisphere ipsilateral to the CE. Five later strokes occurred in group II, one ipsilateral to the CE. Four patients in group III had new strokes. The cumulative stroke rates at 5 years by the life-table method were 17.6% for group I, 16.4% for group II, and 5.6% for group III. The difference between group I and III was significant (P less than 0.05). The results suggest that patients undergoing unilateral CE should have close postoperative monitoring of the contralateral vessel.

Cervical vertebral angioplasty for brain stem ischemia.

Fifty-eight patients underwent unilateral vertebral arterial reconstructions over a 16-year period. Thirty-four underwent carotid operations as well. The first 18 patients underwent vertebral arterial reconstructions in conjunction with carotid endarterectomy as mandated in the Joint Study of Extracranial Arterial Occlusion as a Cause of Stoke. The next 40 underwent vertebral procedures for either brain stem symptoms alone, or for combined cerebral cortical and stem symptoms for specific indications after flow-obstructing carotid lesions had been corrected, but symptoms failed to subside. The surgical procedure consisted of subclavian-vertebral angioplasty except in one patient who underwent a subclavian distal-vertebral bypass graft to the level of the second cervical vertebral body. Syncopal episodes occurred as a major symptom in 16 and was controlled by either carotid and vertebral or vertebral artery operation alone except in four who also required cardiac pacemakers and one who needed correction of aortic stenosis. The long-term follow-up reveals that the stroke rate per average year for the first 14 years of follow-up was 1.2% per patient year with only five strokes having occurred in 410 patient years of follow-up and 70% of the patients having sustained no new neurologic episodes at the fourteenth year. Survival, however, was 45% at the fourteenth year with most deaths caused by myocardial infarction. The surgical procedure of vertebral angioplasty is indicated when bilateral vertebral arterial flow-obstructing lesions are found in patients with brain stem ischemia including drop attacks and syncopal episodes if flow-obstructing carotid lesions have been corrected and symptoms persist. The surgical procedure can be performed with a high degree of safety. The differential diagnosis of drop attacks and syncope in this age group should include, in addition to vertebrobasilar arterial insufficiency, transient cardiac arrhythmias, aortic stenosis, and convulsive disorders.

Rupture of the vein patch: a rare complication of carotid endarterectomy.

Vein patch closure after carotid endarterectomy has been used to reduce the incidence of residual and recurrent stenosis at the carotid bifurcation. A rare but potential serious complication is rupture of the vein patch during the early postoperative period. In our experience of 2359 carotid operations performed from 1962 through 1986, saphenous vein was used for closure in 2275 (96.5%) operations. In three patients out of 75 in whom the vein patch had been harvested from the ankle, rupture of the patch occurred 2 to 5 days after uneventful carotid surgery. At emergency reoperation, the central portion of the vein was necrotic, with no evidence of infection. In each case the carotid artery was closed again with fresh thigh saphenous vein, and recovery was uneventful. The use of ankle vein was discontinued in December 1983 in favor of groin saphenous vein, and similar complications have not occurred in more than 600 carotid endarterectomies performed since. Early noninfectious ruptures of the saphenous vein patches have been mentioned in other reported series of carotid operations and have often been related to the use of ankle vein, but they remain unexplained.

Asymptomatic vena caval fistulization complicating abdominal aortic aneurysm.

Aortocaval fistulization is usually manifested by signs of rupture of an aneurysm or of the large fistula. Absence of symptoms is unusual with this rare complication. Two cases of asymptomatic aortocaval fistula are presented. An awareness of this possibility should facilitate management when unexpected venous bleeding is encountered.

Long-term results in superficial femoral artery endarterectomy.

Semiclosed femoral popliteal endarterectomy, herein described as extending from groin to knee and performed with an arterial stripper, has proved to be a satisfactory alternative to revascularization of comparable occluded segments of thigh arteries employing autologous saphenous vein. Cumulative patency of 95.7% in all groups initially decreases to 59.6% in claudicators at 5 years and 30.6% in those who had surgery for limb salvage, whereas the limb salvage rate exceeds patency rate, being 62.9% at 5 years.

Dilation of synthetic grafts and junctional aneurysms.

Dilation of prosthetic graft has been noted by authors in association with junctional aneurysm between the synthetic graft and host arteries. Dilation of graft materials was suspected as one of the etiologic factors of the junctional aneurysm. Increase in transverse diameter was observed as early as a few minutes to five years postimplantation in clinical cases. The phenomenon of dilation was studied experimentally. Nine different types of graft materials were tested using intraluminal pulse pressure of 100/60 mm Hg, and the transverse diameters were measured at various time intervals. Knitted grafts showed the more pronounced changes compared with the woven. Degree of dilation differed considerably among the different types of knitted grafts.

Criteria for interpretation of ocular pneumoplethysmography (Gee).

Ocular pneumoplethysmography (OPG) (Gee) is one of the most widely used tests for evaluation of carotid artery disease. Its usefulness depends on its diagnostic accuracy, which depends on the criteria used for interpretation of OPG tracings. Application of different criteria as suggested in the literature by Gee et al, McDonald et al, Baker et al, Eikelboom, and O'Hara et al on 200 OPG tests compared with angiography resulted in variations of sensitivity from 70% to 95%, specificity from 70% to 94%, and overall accuracy from 75% to 90%. In validating OPG, one has to be aware of these substantial differences. We found the criteria of McDonald et al the most suitable for clinical use.

Cerebral protection in carotid surgery.

We performed 956 carotid endarterectomies in 661 conscious patients who were under cervical block anesthesia and in whom the stroke rate was 2.5%. They were analyzed to determine the mechanisms of strokes and the risk factor for perioperative stroke. Twenty-three patients with perioperative strokes, regardless of severity, were analyzed as to the mechanism of cause. One half were due to technical problems, one quarter to intraoperative embolization, one sixth to intracerebral hemorrhage, and the remainder were not directly related to the operative procedures. Perioperative stroke rate varied by group from 0.6% to 28.4%, highest when the contralateral carotid was occluded, where there was a preoperative persistent neurologic deficit, and when the patient failed to tolerate carotid clamping. Regional block monitoring was accurate and no stroke could be ascribed to anesthetic technique. Standard reporting techniques should be used in classifying patients into appropriate risk groups to permit meaningful comparisons among groups using different techniques for cerebral protection.

Symptoms, stenosis, and bruit: interrelationships in carotid artery disease.

The relationship between focal neurologic symptoms, carotid artery stenosis, and cervical bruits was studied in 495 patients. Among the 990 carotid arteries, 562 (57%) were considered to be symptomatic and 505 (51%) were associated with bruit. There was a linear relationship between the degree of stenosis and symptoms. Of the highly stenotic vessels (80% to 99% narrowing), 253 of 350 (72%) were symptomatic; 85 of 104 (82%) occluded vessels were symptomatic. There was a linear relationship between the occurrence of cervical bruit and degree of stenosis, up to but not including total occlusion. The relationship between bruits and focal neurologic symptoms was less direct. Among 562 symptomatic arteries, 297 (53%) had a bruit and 265 (47%) did not. In symptomatic patients, the absence of a cervical bruit should not delay a workup for extracranial vascular disease.

Revascularization of the external carotid artery.

Numerous reports describe the relative effectiveness of external carotid artery (ECA) revascularization in patients with ipsilateral internal carotid artery occlusion. Most, however, suffer from small numbers of patients or lack of detailed follow-up data. In addition, controversy persists regarding the safety with which this procedure can be performed. Twenty-two patients underwent a total of 27 ECA revascularizations. There were no perioperative strokes or deaths. During a mean follow-up period of 46 months, no strokes occurred and only two patients suffered transient ischemic attacks. Revascularization of the ECA is an effective means of treating the patient with ipsilateral internal carotid artery occlusion and may be performed with minimal morbidity and mortality.

The totally occluded internal carotid artery. Preliminary observations using rapid sequential computerized tomographic scanning.

Cerebral angiography often cannot distinguish between complete thrombosis or fibrosis of the internal carotid artery (ICA) and nonvisualization due to a total occlusion of the common carotid or origin of the ICA. Whereas surgery may be beneficial if the distal carotid is patent (type 1), thromboendarterectomy may be contraindicated if thrombus or fibrosis extend to the intracranial branches (type 2). Rapid sequential computerized tomography (RSCT) was used to examine 15 patients whose ICAs appeared occluded by angiography. Of four ICAs classed as type 1 by RSCT, three were found to be patent during surgical exploration, and carotid reconstruction was successfully performed. Three other ICAs classed as type 2 by RSCT were also surgically explored, and complete thrombosis was confirmed. The RSCT technique provides an effective and nonoperative means of determining whether a nonvisualized ICA is reconstructible.

Ultrasound evaluation of endovascular repair of abdominal aortic aneurysms.

UNLABELLED: Endovascular repair of an abdominal aortic aneurysm (AAA) offers a minimally invasive alternative to an open surgical procedure in selected patients. The purpose of this study was to examine the usefulness of ultrasonography for evaluating the results of endovascular repair. METHODS: We studied 17 patients who underwent endovascular repair. In 10 patients a bifurcated prosthesis was positioned below the renal arteries with the bifurcated branches in the iliac arteries. The other 7 patients had a nonbifurcated infrarenal prosthesis. RESULTS: In each patient the AAA and the entire prosthesis, including its bifurcated branches, were visualized. The mean AAA diameter was 5.0 +/- 0.6 cm. The mean prosthesis body diameter was 2.2 +/- 0.3 cm, and the diameters of the bifurcated limbs were 1.0 to 1.2 cm. Color Doppler studies revealed blood flow limited to the prosthetic lumen and its bifurcation in 16 patients; the space between the prosthesis and the AAA wall was clotted in these patients. In 1 patient a communication was seen between the prosthesis and the AAA lumen through a dehiscence in the distal attachment. CONCLUSION: Ultrasonography is a simple, noninvasive tool for the evaluation of the results of endovascular repair of AAA and can detect complications of this procedure.

Transesophageal echocardiography in intimal flap fenestration.

In selected patients with descending aortic dissection, percutaneous intimal flap fenestration is a less-invasive alternative to surgery. We describe a patient with decreased renal and mesenteric blood flow as a result of descending aortic dissection. Percutaneous balloon intimal fenestration was performed under guidance of transesophageal echocardiography. Transesophageal echocardiography provided crucial information about the intimal flap puncture site and true- and false-lumen blood flow. After the flap fenestration, false-lumen blood flow increased, and the patient improved clinically.

Diagnosis of carotid artery stenosis: comparison of 2DFT time-of-flight MR angiography with contrast angiography in 50 patients.

Fifty patients underwent 2DFT time-of-flight MR angiography and intraarterial contrast angiography for evaluation of possible carotid atherosclerotic disease. The MR angiography technique employed contiguous axial flow-sensitive (short TR/TE) slices that were reformatted and postprocessed by using a maximum-intensity projection algorithm to provide 16 angiographic views of the carotid arteries. Both studies were independently reviewed by two observers in a blinded manner. Carotid arteries were categorized as normal, mildly stenotic, moderately stenotic, severely stenotic, or occluded. For the 94 carotid arteries available for review, one observer reported a 70% agreement between the two techniques and the second observer reported a 56% agreement (p = .0001). The best correlation was in the severely stenotic category and the worst was in the occluded category. Agreement between observers was 67% for MR angiography and 72% for contrast angiography, which was similar to that between the two techniques. Although not all carotid atherosclerotic disease was visualized equally well, 2DFT time-of-flight MR angiography had a good overall correlation with the "gold standard" of intraarterial contrast angiography, supporting its use as a screening technique. While further improvements are needed, use of MR angiography as the primary diagnostic tool for many patients with suspected carotid stenosis should continue to increase.

Management of acute aortic occlusion.

Acute aortic occlusion is most often seen in elderly patients with advanced cardiac disease. The management of these patients has been facilitated by the use of extraanatomic bypass. Over the past 2 years, six patients aged 55 to 87 years presented to our medical center with acute aortic occlusion, three after major operative procedures. One patient had a thrombosed abdominal aortic aneurysm; in the other five patients differentiation between saddle embolus and thrombosis of the distal aorta was impossible. There was one operative death. Four of the other five patients underwent axillobifemoral bypass and one underwent aortofemoral thrombectomy. All survived, and none required amputation. Two of the three patients who underwent preoperative aortography developed transient renal failure postoperatively. Aortography is of little value in diagnosis and is probably contraindicated in acute aortic occlusion. Our recommendation for operative management includes (1) preparation of the patient for possible axillobifemoral bypass, (2) angiography of distal runoff via both femoral arteries, (3) attempt at bilateral aortofemoral embolectomy with Fogarty catheters, and (4) axillobifemoral bypass if embolectomy fails to restore normal pulsatile flow.

Long-term follow-up of patients undergoing carotid endarterectomy in the presence of a contralateral occlusion.

BACKGROUND: Patients with stenosis of one carotid artery and occlusion of the contralateral carotid artery (stenosis-occlusion) who are treated medically are at high risk for stroke. We have recently reported that carotid endarterectomy on the stenotic artery has a low perioperative risk in these patients. We now present follow-up data to define the long-term effectiveness of this operation. PATIENTS AND METHODS: From 1985 to 1991, 135 patients with stenosis-occlusion underwent endarterectomy of the stenotic carotid artery. Selective intra-arterial shunting was performed based on mental status changes under regional anesthesia, preoperative neurologic deficit, or evidence of preoperative cerebral infarction on computed tomography scan. Shunting was used in 70 patients (52%). Saphenous vein was used for patch closure in 132 patients (98%), and polytetrafluoroethylene in 3 (2%). RESULTS: By life-table analysis, 92% of patients have remained stroke-free at 5 years. Fourteen deaths, none related to cerebrovascular disease, have occurred during follow-up. The life-table cumulative stroke-free survival rate at 5 years is 74%, and the overall survival rate is 82%. CONCLUSION: Carotid endarterectomy in the presence of a contralateral occlusion provides long-term benefit to the patient with respect to prevention of stroke. With lower perioperative stroke rates and proven long-term benefit, carotid endarterectomy of the stenotic artery should be the treatment of choice in the patient with stenosis-occlusion.