Carotid endarterectomy without a shunt for symptomatic lesions associated with contralateral severe stenosis or occlusion

PURPOSE: The purpose of this study was to assess the adequacy of thiopental protection against ischemic cerebral damage in patients undergoing carotid endarterectomy for symptomatic stenosis greater than 70% in association with contralateral stenosis greater than 70% or contralateral occlusion. METHODS: All patients (n=259) with severe bilateral carotid disease who underwent carotid endarterectomy for symptomatic stenosis greater than 70% were extracted from the database of an ongoing prospective carotid surgery study. Large-dose thiopental sodium without shunting was used for cerebral protection during endarterectomy. Asymmetric electroencephalogram changes during the operation, carotid occlusion time, stroke onset, and neuropathologic outcomes were analyzed. RESULTS: Three contralateral strokes occurred in the series, producing a cerebral morbidity/mortality rate of 1.2% (major 0.4%, minor 0.8%). Transient morbidity was 1.9% made of two reversible ischemic neurologic deficits and three transient ischemic attacks. New asymmetric electroencephalography changes were seen in 49 (19% patients, one of whom had transient deficit. Average occlusion time was 35 minutes. All strokes occurred within 24 hours of the procedure. Patients with previous stroke and and systemic hypertension seemed at greatest risk, and the contralateral hemisphere was the area at greatest risk. All transient deficits were ipsilateral and related to technical complications rather failed protection. CONCLUSIONS: Thiopental cerebral protection eliminates strokes caused by complications of shunting, prevents ischemic stroke during carotid occlusion for periods up to 67 minutes (average 35 minutes), allows meticulous management of the operative site, may modify or minimize clinical neurologic deficit, and in our experience has rendered intraluminal shunting obsolete.     

Elective carotid artery stenting in the presence of contralateral occlusion

Significant carotid stenosis in the presence of an occluded contralateral artery has a poor prognosis with medical therapy alone. Carotid cross clamping during surgical endarterectomy results in critical flow reductions in patients with inadequate collateral flow, and represents a significant risk for procedural strokes. Carotid stenting is being evaluated as an alternative to endarterectomy. We describe the immediate and late outcome of a series of 26 patients treated with carotid stenting in the presence of contralateral carotid occlusion. The mean age of the patients in this group was 65 +/- 9 years, 23 (89%) were men and 10 (39%) were symptomatic from the vessel treated. The procedural success of carotid stenting in this group of patients was 96%. The mean diameter stenosis was reduced from 76 +/- 15% to 2.8 +/- 5%. There was 1 (3.8%) minor stroke in a patient who developed air embolism during baseline angiography. At late follow-up there was no neurologic event in any patient at a mean of 16 +/- 9.5 months after the procedure. Thus, carotid stenting of lesions with contralateral occlusion can be performed successfully with a low incidence of procedural neurologic complications and late stroke.     

Surgical treatment of common carotid artery occlusion

Eight patients with common carotid artery (CCA) occlusion underwent bypass with saphenous vein to either the carotid bifurcation (five), the internal carotid artery (two), or the external carotid artery (one). Indications included ipsilateral transient ischemic attack (two), recent nondisabling hemispheric stroke (two), and transient nonhemispheric cerebral symptoms (two). Two asymptomatic patients with CCA occlusion and contralateral internal carotid stenosis underwent prophylactic revascularization prior to planned aortic surgery. There were no perioperative strokes, occlusions, or deaths. Late ipsilateral stroke occurred in two patients, and one patient had a single transient ischemic attack after 2 years. The four patients with preoperative transient cerebral ischemia experienced relief of their symptoms. Duplex ultrasound is an accurate screening modality for distal patency. Collateral filling of the internal or external carotid artery can usually be demonstrated after aortic arch or retrograde brachial contrast injection. End-to-end distal anastomosis after endarterectomy eliminates the original occlusive plaque as a potential source of emboli. The subclavian artery is preferred for inflow on the left. The CCA origin is easily accessible for inflow on the right. Bypass of the occluded CCA is safe and may be effective in relieving transient cerebral ischemic symptoms, although long-term ipsilateral neurologic sequelae may still occur.     

Radiation exposure of the population by roentgen diagnosis. II. The collective effective dosage of the population in former East Germany caused by 1987/1988 roentgen diagnosis

OBJECTIVES: To examine the relations between the development of neurologic events and the following variables: degree of stenosis of the contralateral carotid artery, prior neurologic symptoms and stump pressure of the ipsilateral internal carotid artery in patients undergoing carotid endarterectomy under regional anesthesia. PATIENTS AND METHODS: We undertook a prospective study of 92 patients undergoing carotid endarterectomy with a blockade of the superficial and deep cervical plexus. Neurological integrity was assessed and internal carotid artery stump pressure was monitored. Contralateral carotid artery stenosis and neurologic disease present before surgery were studied. RESULTS: Neurologic events developed when the carotid artery was clamped in 9.7% of patients. Mean stump pressure was significantly lower in symptomatic patients (43 +/- 11 mmHg) than in asymptomatic patients (74.6 +/- 24 mmHg) (p < 0.001). Neurologic symptoms developed during clamping of the carotid in 27.2% of the patients with stump pressure less than or equal to 50 mmHg, but in only 4.2% of those with stump pressure surpassing 50 mmHg. Stump pressure was significantly lower in patients with contralateral carotid stenosis. The incidence of neurologic events during clamping was unrelated to contralateral carotid condition, however. Likewise, neurologic symptoms before surgery was also unrelated. In six of the nine patients with neurologic events, internal carotid stump pressure was less than or equal to 50 mmHg, indicating that the sensitivity of this parameter to the development of neurologic events in our series was 66%. CONCLUSIONS: Although internal carotid artery stump pressure identifies a subset of patients likely to have a higher incidence of neurologic events during carotid artery clamping, it can not be considered the only criterion for placement of an intraluminal shunt to prevent such events. The state of the contralateral carotid artery and preexisting neurologic symptoms are not objective screening criteria for identifying patients at high risk of neurologic events during carotid clamping.     

Incidence, timing, and causes of cerebral ischemia during carotid endarterectomy with regional anesthesia

PURPOSE: Controversy exists regarding the best technique to identify cerebral ischemia during carotid endarterectomy (CEA). Regional anesthesia allows continuous evaluation of neurologic function and therefore can help determine the incidence, timing, and causes of cerebral ischemia. METHODS: The timing and clinical manifestations of any neurologic event during CEA and as long as 30 days afterward was determined by review of operative reports, hospital charts, and outpatient records of consecutive patients who underwent CEA under regional anesthesia over a 68-month period. RESULTS: Two hundred patients underwent CEA; indications were asymptomatic stenosis > 60% in 25%, transient ischemic attack with stenosis > 50% in 52%, and prior stroke with stenosis > 50% in 23%. Eight patients (4%) were converted to general anesthesia for non-ischemic reasons. Of the remaining 192 patients, 183 (95.5%) underwent the procedure with regional anesthesia and no shunt, 2% had cerebral ischemia and underwent shunt placement, and 2.5% had cerebral ischemia, were converted to general anesthesia, and underwent shunt placement. Cerebral ischemia developed in nine patients after carotid cross-clamping, manifested by loss of consciousness in four, confusion in two, dysarthria and confusion in one, and decreased contralateral motor strength in two. Immediate cerebral ischemia developed in four of the nine patients within 1 minute of cross-damping; all four underwent shunt placement. In five of the nine patients, cerebral ischemia occurred between 20 and 30 minutes after cross-clamping; all occurred during relative intraoperative hypotension (average reduction of 35 mm Hg in the systolic pressure). All awake patients in whom ischemic symptoms developed immediately regained and maintained normal neurologic function with shunt placement. Five of 26 patients (19%) with contralateral occlusion required a shunt; none had postoperative ischemia. The mean carotid cross-clamp time was 27 minutes. Postoperative (30 day) complications included a 0.5% stroke rate, a 0.5% rate of postoperative transient ischemic attack, a 0.5% rate of worsening of preexisting acute stroke, and a 0.5% rate of myocardial infarction (no deaths). Of the nine patients who had intraoperative ischemic changes, none had a postoperative neurologic deficit; the three patients who had postoperative neurologic changes had no intraoperative ischemic symptoms. CONCLUSIONS: CEA with regional anesthesia allows continuous neurologic monitoring and can be performed safely even when contralateral occlusion coexists; intraoperative shunting for ischemia is necessary in 4.5% of all cases and in 19% of patients with contralateral occlusion. Intraoperative ischemia was flow-related in our patients; it occurred early from ipsilateral carotid clamping and late from reduced collateral flow as a result of hypotension. Monitoring should be continued throughout cross-clamping to identify late cerebral ischemia. Postoperative cerebral ischemia is not associated with intraoperative ischemia, if corrected.     

Critical carotid artery stenosis: diagnosis, timing of surgery, and outcome

PURPOSE: Patients with critical carotid artery stenoses have been considered to be at high risk for carotid artery occlusion necessitating urgent or emergency endarterectomy once the stenosis is identified. Included in this group of patients are those with carotid string sign or atheromatous pseudoocclusion (APO). This review was conducted to determine the impact of the severity of stenosis including APO on the treatment and outcome of patients undergoing carotid endarterectomy. METHODS: The records of 203 consecutive carotid endarterectomies performed in 197 patients were reviewed in detail. Patients were stratified into a critical stenosis group (80% to 99% diameter) and noncritical stenosis group based on noninvasive vascular laboratory and carotid arteriography results. Comparisons were performed of demographic data, atherosclerotic risk factors, carotid artery disease presentation, interval between arteriography and endarterectomy, operative details, and surgical results between the critical and noncritical groups and between patients in the critical group with and without APO. RESULTS: Carotid endarterectomies were performed on 91 critical carotid artery stenoses and 112 noncritical stenoses. The groups did not differ significantly with regards to demographics, risk factors, carotid artery disease presentation, mean back pressure, and operative use of shunt or patch closure. For the critical group the interval between arteriography and endarterectomy was 8.63 +/- 2.38 days compared with 9.64 +/- 2.14 days for the noncritical group (mean +/- SEM, p = 0.75). No patient in either group progressed to occlusion in the interval between arteriography and endarterectomy. Perioperative strokes occurred in two patients (2%) in the critical group and four patients (3.6%) in the noncritical group (p = 0.09). Likewise, no significant difference was demonstrated in these variables when comparing patients with critical carotid artery stenosis and APO with those without APO. CONCLUSIONS: The presence of a critical carotid artery stenosis including APO did not impact on the treatment or outcome of patients requiring endarterectomy nor did it imply the need for emergency intervention to prevent thrombosis. Surgical intervention can proceed after evaluation and optimization of comorbid conditions without undue concern for interval thrombosis.     

Asymptomatic carotid artery stenosis and stroke in patients undergoing cardiopulmonary bypass

PURPOSE: This study was undertaken to assess the natural history of carotid artery stenosis in patients undergoing cardiopulmonary bypass (CPB) at a Veterans Administration Medical Center. METHODS: Between January 1989 and August 1993, all patients undergoing CPB were offered preoperative carotid artery ultrasound screening as part of an investigative protocol. Patients were monitored in-hospital for the occurrence of perioperative neurologic deficit. RESULTS: A total of 582 patients underwent carotid artery ultrasound screening. Greater than 50% stenosis or occlusion of one or both internal carotid arteries was present in 130 patients (22%), with 80% or greater stenosis or occlusion of one or both arteries present in 70 patients (12%). In-hospital stroke or death occurred in 12 (2.1%) and 36 (6.2%) patients, respectively. Of the 12 strokes, five were global and seven were hemispheric in distribution. Of the five patients who had global events, none had evidence of carotid artery stenosis. However, of the seven patients who had hemispheric events, five had significant 50% or greater stenosis or occlusion of the internal carotid artery ipsilateral to the hemispheric stroke. Therefore the presence of carotid artery stenosis or occlusion was significantly associated with hemispheric stroke (no stenosis 0.34% vs stenosis 3.8%; p = 0.0072). Furthermore, the risk of hemispheric stroke in patients with unilateral 80% to 99% stenosis, bilateral 50% to 99% stenosis, or unilateral occlusion with contralateral 50% or greater stenosis was 5.3% (4 of 75). No strokes occurred in patients with unilateral 50% to 79% stenosis (n = 52). CONCLUSIONS: It is concluded that carotid atherosclerosis is a risk factor for hemispheric stroke in patients undergoing CPB.     

Routine carotid endarterectomy without a shunt, even in the presence of a contralateral occlusion

A 10-year prospective experience with routine non-shunting, even in the presence of a contralateral internal carotid artery occlusion, is reviewed. METHOD AND RESULTS: Carotid endarterectomy was performed without a shunt in 654 consecutive patients: group 1, 513 patients with contralateral stenosis of less than 79%: group 11, 74 patients with a greater than 80% contralateral stenosis; and group 111, 67 patients with a contralateral occlusion. Average cross-clamp time was 23 min. Neurological complications occurred within 30 days in 20 (3.0%) patients (10 strokes, seven transient ischemic attacks in group I, one transient ischemic attack in group II, and one stroke and one transient ischemic attack in group III). Immediate postoperative strokes, i.e. those five cases that could be implicated as caused by lack of a shunt, were rare (0.76%). There were five perioperative deaths (0.76%). CONCLUSION: Carotid endarterectomy may be performed safely without a shunt even in the presence of a contralateral occlusion. Age, sex, preoperative indication, anesthetic agent and contralateral stenosis were not associated with an increased risk of postoperative neurological deficit.     

Unilateral internal carotid arterial occlusion: special considerations

Cases of patients with unilateral internal carotid arterial occlusion and contralateral internal carotid arterial stenosis are reviewed. Forty-two percent presented with a fixed neurological deficit. The deficit was referable to the side of occlusion in 92% and to the side of stenosis in 8%. Eleven percent had a neurological complication following carotid endarterectomy on the side of the stenotic lesion. The neurological complication was referable to the side of stenosis in 67% and to the side of occlusion in 33%. Patients have been followed for an average of 19 months and have not developed any additional TIA's or strokes in the followup period. There may be a role for an extracranial-intracranial bypass (ECIC) on the occluded side prior to an endarterectomy on the stenotic side if a poor collateral situation exists. An ECIC should be done in patients who remain symptomatic following carotid endarterectomy on the stenotic side. These data do not support doing ECIC in asymptomatic patients with unilateral carotid arterial occlusion.     

Local overexpression of thrombomodulin for in vivo prevention of arterial thrombosis in a rabbit model

Data from 213 cases of simultaneous carotid endarterectomy and coronary artery bypass grafting (CEN/CABG) were analyzed (1980-1996). There were 154 males (72.3%), and 59 females (27.7%), (mean age: 65. 6 years, range: 42-83). One hundred and thirty-two patients (62.0%) had angina, 58 (37.2%) had myocardial infarction, and 23 (10.8%) had congestive heart failure. Symptomatic cerebrovascular disease was present in 89 patients (41.7%). One hundred and twenty-two patients (57.2%) had three-vessel coronary artery disease, 41 (19.2%) had left main disease, and 27 (12.6%) had a low ejection fraction (ejection fraction /=75% diameter reduction) stenosis was present in 168 (78.8%) of the operated carotid arteries. The contralateral internal carotid artery was severely stenosed or occluded in 35 patients (16.4%). The hospital mortality rate was 5. 6% (12 patients). The cause of death was cardiac in ten patients (4. 6%), and neurologic in two (1%). Eleven patients (5.1%) developed a stroke postoperatively; eight strokes were ipsilateral to the operated artery, and six were permanent. Myocardial infarction occurred in five patients (2.3%). Independent predictors of early mortality were age >62 years, hypertension, and postoperative stroke (p < 0.05). Male sex was the only independent predictor of neurologic morbidity (p < 0.05). Late follow-up data were obtained for 163 (81.0%) patients (mean: 54.8 months, range: 1-168). Four (9. 3%) out of the 43 late deaths were attributed to strokes. There were three (1.8%) late ipsilateral strokes, and five (3.1%) contralateral strokes. The 5- and 10-year survival probabilities were 75 +/- 4%, and 52 +/- 6.9%. The freedom from late ipsilateral neurologic morbidity at 5 and 10 years were 97 +/- 1.7% and 90 +/- 4.0%, respectively. Taken together, the results indicate that combined carotid endarterectomy and coronary artery bypass grafting can be performed safely in this high-risk group of patients. Excellent long-term freedom from stroke can be expected.     

Carotid artery repair for radiation-associated atherosclerosis is a safe and durable procedure

OBJECTIVE: The development of carotid atherosclerosis after neck irradiation is well documented. There has been concern about the safety and durability of carotid artery repair through a radiated field. The objective of this report is to describe the immediate and long-term results of a series of cases collected in a 13-year interval. METHODS: From 1984 to 1997, 24 patients underwent 26 carotid artery operations. All the patients had undergone prior radiation therapy at a mean interval of 17 years, with an average radiation dose of 6300 rad. Severe scarring of the skin or radiation fibrosis were present in two thirds of the patients, with 4 patients having permanent tracheostomies. The indications for carotid surgery included cerebral or monocular transient ischemic attack (58%), asymptomatic high-grade stenosis (27%), prior stroke (12%), and tumor invasion of the carotid artery (4%). General anesthesia was used with selective shunting on the basis of carotid artery back pressure or electroencephalography monitoring. Patch angioplasty closure was used in 79% of the patients. The operations included standard carotid endarterectomy (n = 20), external carotid endarterectomy (n = 2), carotid patch angioplasty alone (n = 2), aortocarotid bypass grafting (n = 1), and carotid interposition grafting (n = 1). Four patients required skin grafting or myocutaneous flaps. RESULTS: No deaths or strokes occurred within 30 days of the operations. Six patients had transient cranial nerve palsy, and two had wound infections. The patients were followed from 1 to 156 months, with six patients being followed for longer than 18 months. No strokes were seen at late follow-up examination. Duplex scan examination documented one occlusion, in a patient with primary closure, and two restenoses, one of which necessitated reoperation. The remainder of the grafts were widely patent. CONCLUSIONS: Carotid surgery after neck irradiation is safe and durable. The long-term patency rates and the protection against subsequent neurologic events are similar to the results obtained in the absence of radiation therapy. Problems of wound healing were not found in this series.     

Outcome of moderate carotid artery stenosis in patients who are asymptomatic

PURPOSE: The incidence rate of disease progression and stroke after the diagnosis of a moderate (50% to 79%) carotid stenosis was determined by means of color-flow duplex scanning. METHODS: During a 4-year period, 344 male veterans with moderate internal carotid artery stenoses, on one or both sides, were examined at regular intervals for a mean period of 25 months. Carotid color-flow scans were obtained semiannually. Clinical follow-up was performed to determine the incidence rate of amaurosis fugax, transient ischemic attacks, nonhemispheric symptoms, and strokes. RESULTS: New neurologic symptoms developed in 75 patients (21.8%). Fifty-one (14.8%) had ipsilateral symptoms during follow-up: 18 amaurosis fugax (5.2%), 14 transient ischemic attacks (4%), 5 nonhemispheric symptoms (1.4%), and 14 strokes (4%). Twenty-four patients (6.9%) had contralateral symptoms: 20 strokes (5.8%) and 4 transient ischemic attacks (1.2%). Life-table analysis showed that the annual rate of ipsilateral neurologic events was 8.1%, and the annual rate of stroke was 2.1%. Seventy-five patients (22%) died in the follow-up period. Disease progression to 80% to 99% stenosis or occlusion occurred in 71 of 458 vessels (15.5%). The internal carotid arteries that showed evidence of disease progression had a significantly higher initial peak systolic velocity (251 vs 190 cm/s; P <.0001) and end diastolic velocity (74 vs 52 cm/s; P < 0.0001). Black patients and patients with ischemic heart disease were at a higher risk for disease progression. We could not identify any atherosclerotic risk factors that reliably predicted patients in whom future ipsilateral neurologic symptoms were more likely to develop. However, there was an increased risk of stroke associated with progression of disease. CONCLUSION: Patients who are asymptomatic and who have moderate carotid stenoses are at significant risk for neurologic symptoms and death, but have a relatively low incidence rate of ipsilateral events. The initial flow characteristics in the stenotic vessel are predictive of future disease progression, but they are not helpful in identifying patients in whom symptoms will develop.     

Symptomatic recurrent carotid stenosis and aneurysmal degeneration after endarterectomy

BACKGROUND: Aneurysmal degeneration of a carotid reconstruction was not recognized until the patient, who was known to have recurrent carotid artery stenosis, had a thromboembolic stroke. This sequelae of carotid endarterectomy is a serious complication, associated with a high morbidity and mortality rate. This review was conducted to establish the risk of transient ischemic attack and stroke for patients found to have recurrent carotid stenosis associated with aneurysmal degeneration of the carotid artery after endarterectomy. METHODS: A case is reported, and 100 literature references of aneurysmal degeneration of the carotid artery after endarterectomy were reviewed. RESULTS: False aneurysm from anastomotic disruption was the most common presentation identified in the cases reviewed. Nineteen of the patients had a significant neurologic event; however, three (50%) of six patients with aneurysm and recurrent carotid artery stenosis had a transient ischemic attack or stroke. CONCLUSIONS: The incidence of neurologic symptoms is markedly increased when recurrent carotid artery stenosis is associated with carotid aneurysm. During postoperative surveillance after endarterectomy, the identification of recurrent carotid artery stenosis requires evaluation for aneurysmal degeneration of the carotid artery with duplex scanning. These patients are at significant risk for transient ischemic attack and stroke. This rare complication merits operative repair.     

Extrathoracic bypass procedures for proximal common carotid artery lesions

During a 10-year period ending in December 1991, 31 extrathoracic bypass procedures were performed in 29 patients for proximal common carotid artery atherosclerotic stenosis or occlusion. This included 16 men and 13 women, with a mean age of 63 years. Indications for surgery included transient ischemic attacks in 23 patients (79%), nonfocal symptoms in 4 patients (14%), and asymptomatic proximal common carotid artery stenosis associated with near-total occlusion of the internal carotid artery in 2 patients (7%). Severe proximal stenosis or complete occlusion of the common carotid artery was demonstrated angiographically in all cases. Subclavian-to-carotid bypass was performed in 26 cases and carotid-to-carotid bypass in 5 cases. Seventy-four percent of the bypass procedures were to the common carotid artery and 26% to the external carotid artery. Endarterectomy of the common carotid bifurcation was performed in conjunction with the bypass procedure in 13 cases and vertebral artery transposition in 2 other cases. Saphenous vein was used as the bypass conduit in 65% and prosthetic grafts in 35% of cases. There were no perioperative strokes or deaths in this series, and the mean postoperative hospital stay was 5 days. Follow-up ranged from 2 to 118 months (mean: 38.4 months). Graft occlusion occurred in two cases during the follow-up period (3-year patency rate: 90%), with recurrence of symptoms in one patient, which necessitated revision. Three patients had persistence or recurrence of symptoms despite patency of the graft, one other patient sustained a posterior circulation infarct, and there was one death unrelated to carotid vascular disease during the follow-up period. This experience shows that extrathoracic bypass procedures are safe and well tolerated for symptomatic proximal common carotid artery stenosis or occlusion. This method of reconstruction has excellent long-term patency and protection against further anterior circulation neurologic events.     

Staged intracranial and extracranial revascularization

Twenty patients with a combination of intracranial and extracranial cerebrovascular lesions were identified in a series comprised of 118 candidates for superficial temporal artery to middle cerebral artery (STA-MCA) bypass. Ten patients had internal carotid (ICA) occlusion and contralateral ICA stenosis, seven patients had combinations of ipsilateral lesions, usually ICA occlusion and external carotid (ECA) stenosis, and three patients had multiple lesions. Eighteen patients had a STA-MCA bypass performed; 11 of these had contralateral reconstruction for ICA stenosis, and seven had ECA stenosis corrected. Two additional patients became asymptomatic after ECA endarterectomy only and their proposed STA-MCA bypass has been postponed. There were two deaths, one early and one late. Eleven patients are asymptomatic, five are improved, one is unchanged, and one is neurologically worse.     

A surgical approach to coexistent coronary and carotid artery disease

OBJECTIVE: To assess the early results of combined coronary artery bypass graft surgery and carotid endarterectomy. DESIGN: Retrospective and ongoing analysis of patients who underwent combined coronary artery bypass graft surgery and carotid endarterectomy. SETTING: Cardiothoracic unit in a London teaching hospital. PATIENTS: From June 1987 to March 1995, 64 patients were identified. They were patients who were scheduled to have coronary artery bypass graft surgery or required urgent coronary revascularisation and who were found to have significant coexistent carotid disease. (Unilateral carotid stenosis > 70%, bilateral carotid stenosis > 50%, or unilateral carotid stenosis > 50% with contralateral occlusion.) INTERVENTIONS: Both procedures were performed during one anaesthesia: the carotid endarterectomy was performed first without cardiopulmonary bypass. After completion of carotid endarterectomy, coronary artery bypass graft surgery was performed. MAIN OUTCOME MEASURES: The incidence of stroke, transient ischaemic attack, and myocardial infarction in the early postoperative period was analysed. RESULTS: Myocardial revascularisation was successful in all 64 patients. There were no perioperative infarcts. In three patients (4.7%) a new neurological deficit developed postoperatively: two recovered fully before hospital discharge. CONCLUSIONS: Combined coronary artery bypass graft surgery and carotid endarterectomy were performed safely and with good results.     

Carotid endarterectomy for asymptomatic carotid artery stenosis: patients with severe bilateral disease a high risk subgroup

Carotid endarterectomy if advised for asymptomatic disease must be associated with a low peri-operative morbidity and mortality and satisfactory long-term results. Over a 12 year period between 1978-1989 181 carotid endarterectomies were performed on 163 patients with asymptomatic carotid artery stenosis. There were 112 males and 51 females with a mean age of 64.9 years. All patients had a high-grade lesion (> 70% stenosis). The combined operative mortality and stroke rate was 2.8%. On long-term follow up six patients suffered a stroke. Only one patient however sustained a stroke in the same territory as the previously operated carotid artery. Four years following surgery 78% of patients were alive. Carotid restenosis or occlusion occurred in 8.3% of the remaining patients, all of whom were asymptomatic. All the immediate postoperative strokes occurred in patients with severe bilateral carotid artery disease. These patients with severe bilateral disease appear to constitute a high risk sub-group for peri-operative stroke. The role of 'normal pressure-hyperperfusion breakthrough' syndrome as the presumed aetiology of two of the postoperative cerebral haemorrhages is discussed.     

EMT defibrillation does not increase survival from sudden cardiac death in a two-tiered urban-suburban EMS system

BACKGROUND: The aim of this article was to analyze the perioperative mortality and stroke risk rates and late benefits of carotid endarterectomy (CE) contralateral to an occluded internal carotid artery (ICA), on the basis of our surgical experience from July 1990 to June 1996. METHODS: In 57 (14.7%) of 336 patients undergoing 388 CEs, the contralateral ICA was occluded (group I). All operations were performed under general anesthesia with selective shunting based on electroencephalographic criteria. Shunting was used in 36 (63.1%) of 57 revascularizations in group I and 47 (14.2%) of 331 operations performed on the remaining 279 patients with patent contralateral ICAs (group II) (p < 0.001). RESULTS: Perioperative strokes occurred in two patients (3.5%) in group I and three patients (1%) in group II (difference not significant). The only perioperative death, which occurred in one patient (1.7%) in group I, was the result of a perioperative stroke; two patients (0.7%) in group II died within 30 days of operation (difference not significant). Life-table cumulative stroke-free rates at 1, 3, and 5 years were 95%, 95%, 95% in group I and 98.8%, 98.2%, and 98.2% in group II, respectively (p = 0.272). Life-table cumulative survival rates at 1, 3, and 5 years were 97.5%, 94.2%, and 78.1% in group I and 99.2%, 94.8%, and 71.7% in group II, respectively (p = 0.306). CONCLUSIONS: The results of this analysis indicate that CE contralateral to an occluded ICA can be performed with acceptable perioperative mortality and stroke risk rates and late stroke-free and survival rates comparable to those seen in patients without contralateral ICA occlusion who have undergone operation. Nevertheless, we think it is misleading to imply that the risks of operating on the two groups are the same. Moreover, because no late stroke-related death occurred in patients with contralateral ICA occlusion, it would appear that superior late stroke-free rates did not translate into a prolonged survival advantage.     

Combined carotid endarterectomy and coronary artery bypass grafting in asymptomatic carotid artery stenosis

The role of combined carotid endarterectomy (CEA) and coronary artery bypass grafting (CABG) in patients with severe asymptomatic carotid artery disease and concurrent symptomatic coronary artery disease is controversial. The objective of this report is to investigate the safety of combined CEA/CABG. The medical records of 30 patients who underwent combined CEA/CABG for coexistent asymptomatic carotid and symptomatic coronary artery occlusive disease were reviewed. All patients were scheduled for either elective or urgent myocardial revascularization due to their symptomatic coronary artery disease. Color-flow duplex scanning identified internal carotid artery stenosis of 80 to 99 per cent in 28 patients (93%) and 50 to 79 per cent in 2 patients (7%). Seventeen patients (57%) were male. The mean age was 64 +/- 10 years (range, 42-84 years). Contralateral internal carotid artery occlusion was present in four patients. Severe left main coronary artery disease was present in 12 patients (40%) and 7 patients (23%) had an ejection fraction of less than 50 per cent. There were no perioperative deaths or strokes. One patient suffered a myocardial infarction on postoperative day 1. This study demonstrates the safety of combined CEA/CABG for coexistent coronary and asymptomatic carotid disease. Using this surgical approach for critical coexistent disease may minimize the incidence of perioperative cerebrovascular complications in patients undergoing CABG.     

Prevalence of asymptomatic carotid stenosis in patients undergoing infrainguinal bypass surgery

BACKGROUND: The prevalence of asymptomatic carotid stenosis in patients with lower-extremity ischemia is unknown. This report represents the largest carotid screening program to date of patients undergoing leg bypass. DESIGN: Patients undergoing infrainguinal bypass from 1987 through 1993 on the vascular surgery service at Oregon Health Sciences University, Portland, underwent routine carotid duplex examinations to detect the presence of asymptomatic carotid stenosis. PATIENTS: During the study period, 352 patients underwent infrainguinal revascularization for ischemia, of whom 225 (64%) had no prior carotid surgery, carotid arteriography, or cerebrovascular symptoms. There were 117 men and 108 women, with a mean age of 67 years. The indication for surgery was limb salvage in 67% and claudication in 33% of patients. RESULTS: Sixty-four patients (28.4%) who required lower-extremity revascularization had hemodynamically significant asymptomatic carotid artery stenosis or occlusion; 12.4% had stenosis of 60% or greater, the qualifying level for randomization in the Asymptomatic Carotid Atherosclerosis Study. Based on these findings, eight patients with carotid stenosis of 80% or greater underwent elective carotid endarterectomy. There were no postoperative neurologic events in the 225 leg bypass patients. By multivariate logistic regression analysis, the presence of carotid bruit (P < .001) and the presence of rest pain (P = .006) were associated with carotid stenosis of 50% or greater. Limiting screening to patients with carotid bruit, limb salvage indications for surgery, and/or advanced age excluded significant numbers of patients with stenosis; thus, these were not effective screening strategies. CONCLUSION: Screening carotid duplex scanning is indicated in patients who require lower-extremity revascularization.