Late outcome of untreated asymptomatic carotid disease following cardiovascular operations

Prevalence of extracranial carotid atherosclerosis in the patients with coronary artery disease in a tertiary hospital in Malaysia

There is limited information regarding the prevalence of extracranial carotid atherosclerosis in the patients with coronary artery disease (CAD) undergoing coronary artery bypass graft (CABG) surgery in South East Asia. The primary objective was to assess the prevalence of extracranial carotid stenosis, raised carotid intima media thickness (CIMT), and plaques in the patients with CAD undergoing elective CABG. The secondary objective was to evaluate the risk factors for extracranial carotid atherosclerosis.A total of 119 consecutive patients with CAD undergoing elective CABG in a tertiary hospital in Malaysia were recruited. Data on the demographic characteristics and risk factors were collected. The ultrasound carotid Doppler findings comprising of raised CIMT, plaques, and stenosis in the extracranial carotid vessels were recorded.The mean age of the patients was 64.26 ± 10.12 (range 42-89). Most of the patients were men (73.1%). The patients consisted of 44 (37%) Malays, 26 (21.8%) Chinese, and 49 (41.2%) Indians.A total of 67 (56.3%) patients had raised CIMT, 89 (74.8%) patients had plaques, and 10 (8.4%) patients had stenosis in the internal and common carotid arteries. The mean age of patients with plaques was higher compared to those without plaques (66.00 ± 9.63 vs 59.10 ± 9.92, P = .001). The body mass index (BMI) of patients with stenosis was higher compared to those without stenosis (28.35 ± 4.92 vs 25.75 ± 3.16, P = .02).The patients with plaques were more likely to be older, whereas the patients with carotid stenosis were more likely to have higher BMI.

Low prevalence of significant carotid artery disease in Iranian patients undergoing elective coronary artery bypass

BACKGROUND

Coronary artery bypass grafting ranks as one of the most frequent operations worldwide. The presence of carotid artery stenosis may increase the stroke rate in the perioperative period. Routine preoperative noninvasive assessment of the carotid arteries are recommended in many institutions to reduce the stroke rate.

METHODS

271 consecutive patients undergoing coronary artery bypass grafting at Shaheed Madani hospital of Tabriz, Iran (age, 58.5 Y; 73.1% male) underwent preoperative ultrasonography for assessment of carotid artery wall thickness.

RESULTS

Plaque in right common, left common, right internal and left internal carotid arteries was detected in 4.8%, 7.4%, 43.2% and 42.1% of patients respectively. 5 patients (1.8%) had significant (<50%) and 3 (1.1%) patients had critical (<70%) stenosis in internal carotid arteries. Plaque formation in common carotid was not significantly different between two genders but the stenosis of left internal carotid was more frequently seen among men. Patients with plaques in right or left internal carotid arteries were significantly older.

CONCLUSION

Consecutive Iranian patients undergoing elective coronary artery bypass surgery show a very low prevalence of significant carotid artery disease.

Preoperative carotid artery screening in patients undergoing coronary artery bypass graft surgery

BACKGROUND

The incidence of stroke is 2.1-5.2% in bypass surgery patients with a mortality of 0-38%. This study was designed to evaluate the incidence of significant carotid artery stenosis and its related risk factors in candidates for coronary artery bypass graft (CABG) surgery.

METHODS

One thousand forty five consecutive candidates for CABG underwent carotid artery Doppler examination in a prospective study. The relation of age, sex, smoking and diabetes history, as well as lipid profile with carotid stenosis, was evaluated.

RESULTS

In 1045 CABG candidates with a mean age of 60 years, prevalence of significant carotid stenosis (>60%) was 6.9%. In the patients aged 65 years and older, the rate of significant stenosis was 12.5%. Age >50 years, female gender, hypercholesterolemia and diabetes mellitus are independent risk factors for significant carotid stenosis.

CONCLUSIONS

Significant carotid stenosis has an earlier appearance in our study. Cost-effectiveness studies are recommended for revising the previous screening protocols.

Prevalence of carotid artery stenosis in patients with coronary artery disease in Japanese population

BACKGROUND AND PURPOSE

Prevalence of carotid artery stenosis in patients with coronary artery disease (CAD) is unknown in Japanese population.

METHODS

The study populations consisted of 632 consecutive patients who underwent coronary angiography because of suspicion of CAD. All patients underwent carotid ultrasonography to screen carotid artery stenosis before coronary angiography. We defined echographic carotid stenosis as area stenosis of >50% or peak systolic velocity of >200 cm/s.

RESULTS

Echographic carotid stenosis was observed in 124 patients (19.6%). Coronary angiography revealed 433 patients had CAD. Prevalence of echographic carotid artery stenosis was 14 of 199 (7.0%), 18 of 124 (14.5%), 28 of 131 (21.4%), and 64 of 178 (36.0%) in patients with 0-, 1-, 2-, and 3-vessel CAD, respectively (P<0.0001). The prevalence rate with carotid stenosis and CAD was 25.4%. Multivariate stepwise logistic regression analysis showed that age and the extent of CAD were independently related to the presence of carotid stenosis (P=0.0002 and <0.0001, respectively).

CONCLUSIONS

Prevalence of carotid stenosis in patients with CAD is high in Japan as well as in Western countries. Screening of carotid artery stenosis is recommended especially in older patients with multivessel CAD.

Routine preoperative carotid duplex scanning in patients undergoing open heart surgery: is it worthwhile?

It has been reported that carotid screening may be cost-effective in patient populations in which the prevalence of severe carotid stenosis exceeds 4.5%. In order to identify potential patient populations who might benefit from carotid screening, we examined the results of preoperative duplex scanning in patients undergoing open heart surgery. Between January 1995 and July 1998, 3708 patients (59% male, 41% female) underwent open heart surgery at our institution. Of these, 3081 underwent coronary artery bypass grafting (CABG), 364 underwent valve replacement (VR), and 263 underwent CABG and VR. The ages of these patients ranged from 40 years to 98 years (mean 68 +/- 11 years). The risk factors analyzed included hypertension (HTN), 59%; smoking (Smk), 53%; and diabetes (DM), 33%. Patients were divided into three groups according to their age. Group A consisted of the 835 patients who were < or = 60 years old, group B consisted of 2474 patients ranging from 61 years to 80 years old, and group C consisted of 399 patients who were > or = 81 years old. All patients underwent bilateral preoperative carotid duplex scans at an Intersocietal Commission for the Accreditation of Vascular Laboratories (ICAVL)-accredited vascular laboratory. Statistical analyses were performed using chi-squared, Fisher's exact test, linear regression, and multivariate analysis. From our results we concluded that carotid screening is not recommended for patients under 60 years of age who are undergoing CABG unless they present with a minimum of two of the following major risk factors: hypertension, diabetes, or smoking. However, carotid screening is recommended for all patients undergoing open heart operations who are over the age of 60 years old, regardless of the absence of associated risk factors.

Reconstructive surgery of the extracranial arteries

The first carotid endarterectomy (CEA) is usually accredited to Eastcott who reported in 1954 the successful incision of a diseased carotid bulb with end-to-end anastomosis of the internal carotid artery (ICA) to the common carotid artery (CCA). During the following years surgeons were quick to adopt and improve the intuitively attractive procedure. But by the early to mid 1980s several leading neurologists began to question the growing number of CEAs performed at that time. Six major CEA trials were then designed which are now completed or nearing completion. Most conclusive data are available from the North American Symptomatic Carotid Endarterectomy Trial (NASCET) for symptomatic carotid disease, and from the Asymptomatic Carotid Atherosclerosis Study (ACAS) for asymptomatic carotid disease. The key result of these studies is that CEA is beneficial to high grade symptomatic and asymptomatic carotid stenosis. While the benefit in symptomatic disease is clear, it may be negligible in asymptomatic patients suffering from other medical conditions, the most important being coronary artery disease. Since the conclusions from the different studies vary significantly, guidelines and recommendations with regard to CEA have been issued by a number of interest groups, so-called consensus conferences. The best known guidelines are published by the American Heart Association (AHA). However, the practice of interest groups to issue guidelines is currently being criticized, the main reason being that interest groups have different ideas and all claim the right to issue guidelines. At present we recommend CEA for symptomatic high-grade stenosis in patients without significant coincident disease. With regard to asymptomatic stenosis we suggest surgery to otherwise healthy patients if the stenosis is very narrow or progressive. Preoperative evaluation has changed over the years. Currently we recommend duplex sonography in combination with intra- and extracranial magnetic resonance angiography (MRA). Concurrent coronary artery disease is a major consideration in the perioperative management, and the use of a specific algorithm is recommended. Surgery is performed under general anaesthesia with intraoperative monitoring such as electroencephalography (EEG) and transcranial Doppler (TCD). A temporary intraluminal shunt is used selectively if after cross-clamping the flow velocity in the middle cerebral artery (MCA) falls to below 30 to 40% of baseline. For years we employed routine barbiturate neuroprotection during cross-clamping. At the present time we use barbiturate selectively, if the flow velocity in the MCA falls to below 30 to 40% of baseline and if the use of a temporary intraluminal shunt is not possible due to difficult anatomic conditions. The reason to abandon systematic barbiturate protection was to accelerate recovery from anaesthesia. Our patients are monitored overnight on the ICU or a surveillance unit. Routine hospitalization after surgery is 5 to 7 days with a control duplex sonography being performed prior to discharge. A number of details with regard to surgical technique and perioperative management are a matter of discussion. Our surgical routine is described here step by step. Such management resulted in 6 major complications among the 402 cases with 4 of cardiopulmonary and 2 of cerebrovascular origin. For the future we can expect the development of percutaneous transluminal techniques competing with standard carotid endarterectomy. At the present time several comparative studies are under way. Irrespective of the technical approach to treat carotid stenosis, several other issues have to be clarified before long. One of the major unresolved items is the timing of treatment after completed stroke. In this regard prospective trials need to be performed. Although numerically not as important as carotid stenosis, vertebral artery (VA) and subclavian artery (SA) stenoses are more and more accepted as indication for surgical

Combined carotid endarterectomy and coronary revascularization operation

The increasing risk of perioperative stroke after coronary artery bypass grafting can in part be attributed to the increased incidence of carotid stenosis with increasing patient age. The efficacy of carotid endarterectomy has been demonstrated for both symptomatic and asymptomatic patients. Combined operations yield acceptable mortality and stroke risks, provide good freedom from late events, and cost less than staged operations.

Coronary artery bypass grafting in patients with cerebrovascular disease

The incidence of carotid artery disease in patients undergoing coronary artery bypass grafting appears to be increasing as our population ages. The optimal treatment for these high-risk patients with concomitant carotid and coronary artery disease remains controversial. This review focuses on the management of patients with coexistent carotid and coronary arteriosclerosis. The significance and management of the patient with an asymptomatic carotid stenosis in patients undergoing coronary artery bypass grafting and the role of combined coronary artery bypass grafting and carotid endarterectomy in these patients will be discussed.

Screening carotid ultrasonography and risk factors for stroke in coronary artery surgery patients

BACKGROUND

The role of noninvasive carotid artery screening in relation to other clinical variables in identifying patients at increased risk of stroke after coronary artery bypass grafting was examined.

METHODS

Preoperative, intraoperative, and postoperative clinical data were prospectively collected for 1,835 consecutive patients undergoing first-time isolated coronary artery bypass grafting between March 1990 and July 1995, 1,279 of whom had screening carotid ultrasonography. All patients with postoperative neurologic events were identified and reviewed in detail. Average patient age was 65.3 years (range, 33 to 92 years), and 9.3% (171 patients) had a prior permanent stroke or transient ischemic attack. Hospital and 30-day mortality was 2.2% (41 patients). Forty-five patients (2.5%) had a transient or permanent postoperative neurologic event. The data were analyzed by stepwise logistic regression to determine the independent predictors of both significant carotid stenosis and stroke.

RESULTS

On multivariate analysis, the clinical predictors of significant carotid stenosis were age (p < 0.0001), diabetes (p = 0.0123), female sex (p = 0.0026), left main coronary stenosis greater than 60% (p < 0.0001), prior stroke or transient ischemic attack (p = 0.0008), peripheral vascular disease (p = 0.0001), prior vascular operation (p = 0.0068), and smoking (p < 0.0001). When all variables were evaluated for those patients who underwent noninvasive carotid artery screening, the independent predictors of postoperative neurologic event were prior stroke or transient ischemic attack (p < 0.0001), peripheral vascular disease (p = 0.0037), postinfarction angina pectoris (p = 0.0319), postoperative atrial fibrillation (p = 0.0014), carotid stenosis greater than 50% (p = 0.0029), cardiopulmonary bypass time (p = 0.0006), significant aortic atherosclerosis (p = 0.0054), postoperative amrinone or epinephrine use (p = 0.0054), and left ventricular ejection fraction less than 0.30 (p = 0.0744).

CONCLUSIONS

The etiology of postoperative stroke is multifactorial. Selective use of carotid ultrasonography is of value in identifying patients who are at greater risk of postoperative stroke independent of other variables and should be considered before coronary artery bypass grafting, particularly in patients with a history of neurologic event or peripheral vascular disease.

Cost reduction by combined carotid endarterectomy and coronary artery bypass grafting

A significant cost reduction is likely if patients who require coronary artery bypass grafting with significant carotid stenosis have simultaneous carotid endarterectomy and bypass grafting, provided risk is not increased. To investigate this issue, we retrospectively identified cases from February 1977 to May 1994 with first-time isolated carotid endarterectomy, coronary bypass, or combined procedures. In the isolated carotid endarterectomy population, median age was 69 years and 58% (85/146) were male, as compared with 68 years and 68% (68/100) male in the combined group; median age of the coronary bypass cohort was 65 years and 76% (381/500) male. A significantly higher percentage of patients in the coronary bypass versus combined group were in New York Heart Association functional class IV. In the combined group there was a significantly higher incidence of older age, diabetes, hypertension, hyperlipidemia, renal failure, and congestive heart failure. There was no difference among the three groups with respect to hospital mortality (0%, 3.4%, and 4.0%, respectively) and permanent stroke (0.7%, 1.2%, and 0%, respectively). Hospital costs were $4,896, $10,959 and $11,089, respectively, with a savings of $4,766 (30%), and Medicare hospital reimbursement was $8,575, $23,071, and $23,071, respectively, with a savings of $10,077 (25.3%). Thus, in appropriate patients, a combined procedure is cost effective, eliminating a second surgical procedure and the cost of the postoperative stay (3.7 +/- 2.4 days) associated with isolated carotid endarterectomy. Risk of permanent stroke or death is not increased.

Guidelines for carotid endarterectomy. A multidisciplinary consensus statement from the Ad Hoc Committee, American Heart Association

BACKGROUND AND PURPOSE

Indications for carotid endarterectomy have engendered considerable debate among experts and have resulted in publication of retrospective reviews, natural history studies, audits of community practice, position papers, expert opinion statements, and finally prospective randomized trials. The American Heart Association assembled a group of experts in a multidisciplinary consensus conference to develop this statement.

METHODS

A conference was held July 16-18, 1993, in Park City, Utah, that included recognized experts in neurology, neurosurgery, vascular surgery, and healthcare planning. A program of critical topics was developed, and each expert presented a talk and provided the chairman with a summary statement. From these summary statements a document was developed and edited onsite to achieve consensus before final revision.

RESULTS

The first section of this document reviews the natural history, methods of patient evaluation, options for medical management, results of surgical management, data from position statements, and results to date of prospective randomized trials for symptomatic and asymptomatic patients with carotid artery disease. The second section divides 96 potential indications for carotid endarterectomy, based on surgical risk, into four categories: (1) Proven: This is the strongest indication for carotid endarterectomy; data are supported by results of prospective contemporary randomized trials. (2) Acceptable but not proven: a good indication for operation; supported by promising but not scientifically certain data. (3) Uncertain: Data are insufficient to define the risk/benefit ratio. (4) Proven inappropriate: Current data are adequate to show that the risk of surgery outweighs any benefit.

CONCLUSIONS

Indications for carotid endarterectomy in symptomatic good-risk patients with a surgeon whose surgical morbidity and mortality rate is less than 6% are as follows. (1) Proven: one or more TIAs in the past 6 months and carotid stenosis > or = 70% or mild stroke within 6 months and a carotid stenosis > or = 70%; (2) acceptable but not proven: TIAs within the past 6 months and a stenosis 50% to 69%, progressive stroke and a stenosis > or = 70%, mild or moderate stroke in the past 6 months and a stenosis 50% to 69%, or carotid endarterectomy ipsilateral to TIAs and a stenosis > or = 70% combined with required coronary artery bypass grafting; (3) uncertain: TIAs with a stenosis < 50%, mild stroke and stenosis < 50%, TIAs with a stenosis < 70% combined with coronary artery bypass grafting, or symptomatic, acute carotid thrombosis; (4) proven inappropriate: moderate stroke with stenosis < 50%, not on aspirin; single TIA, < 50% stenosis, not on aspirin; high-risk patient with multiple TIAs, not on aspirin, stenosis < 50%; high-risk patient, mild or moderate stroke, stenosis < 50%, not on aspirin; global ischemic symptoms with stenosis < 50%; acute dissection, asymptomatic on heparin. Indications for carotid endarterectomy in asymptomatic good-risk patients performed by a surgeon whose surgical morbidity and mortality rate is less than 3% are as follows. (1) Proven: none. As this statement went to press, the National Institute of Neurological Disorders and Stroke issued a clinical advisory stating that the Institute has halted the Asymptomatic Carotid Atherosclerosis Study (ACAS) because of a clear benefit in favor of surgery for patients with carotid stenosis > or = 60% as measured by diameter reduction. When the ACAS report is published, this indication will be recategorized as proven. (2) acceptable but not proven: stenosis > 75% by linear diameter; (3) uncertain: stenosis > 75% in a high-risk patient/surgeon (surgical morbidity and mortality rate > 3%), combined carotid/coronary operations, or ulcerative lesions without hemodynamically significant stenosis; (4) proven inappropriate: operations with a combined stroke morbidity and mortality > 5%.

Guidelines for carotid endarterectomy. A multidisciplinary consensus statement from the ad hoc Committee, American Heart Association

BACKGROUND AND PURPOSE

Indications for carotid endarterectomy have engendered considerable debate among experts and have resulted in publication of retrospective reviews, natural history studies, audits of community practice, position papers, expert opinion statements, and finally prospective randomized trials. The American Heart Association assembled a group of experts in a multidisciplinary consensus conference to develop this statement.

METHODS

A conference was held July 16-18, 1993, in Park City, Utah, that included recognized experts in neurology, neurosurgery, vascular surgery, and healthcare planning. A program of critical topics was developed, and each expert presented a talk and provided the chairman with a summary statement. From these summary statements a document was developed and edited onsite to achieve consensus before final revision.

RESULTS

The first section of this document reviews the natural history, methods of patient evaluation, options for medical management, results of surgical management, data from position statements, and results to date of prospective randomized trials for symptomatic and asymptomatic patients with carotid artery disease. The second section divides 96 potential indications for carotid endarterectomy, based on surgical risk, into four categories: (1) Proven: This is the strongest indication for carotid endarterectomy; data are supported by results of prospective contemporary randomized trials. (2) Acceptable but not proven: a good indication for operation; supported by promising but not scientifically certain data. (3) Uncertain: Data are insufficient to define the risk/benefit ratio. (4) Proven inappropriate: Current data are adequate to show that the risk of surgery outweighs any benefit.

CONCLUSIONS

Indications for carotid endarterectomy in symptomatic good-risk patients with a surgeon whose surgical morbidity and mortality rate is less than 6% are as follows. (1) Proven: one or more TIAs in the past 6 months and carotid stenosis > or = 70% or mild stroke within 6 months and a carotid stenosis > or = 70%; (2) acceptable but not proven: TIAs within the past 6 months and a stenosis 50% to 69%, progressive stroke and a stenosis > or = 70%, mild or moderate stroke in the past 6 months and a stenosis 50% to 69%, or carotid endarterectomy ipsilateral to TIAs and a stenosis > or = 70% combined with required coronary artery bypass grafting; (3) uncertain: TIAs with a stenosis < 50%, mild stroke and stenosis < 50%, TIAs with a stenosis < 70% combined with coronary artery bypass grafting, or symptomatic, acute carotid thrombosis; (4) proven inappropriate: moderate stroke with stenosis < 50%, not on aspirin; single TIA, < 50% stenosis, not on aspirin; high-risk patient with multiple TIAs, not on aspirin, stenosis < 50%; high-risk patient, mild or moderate stroke, stenosis < 50%, not on aspirin; global ischemic symptoms with stenosis < 50%; acute dissection, asymptomatic on heparin. Indications for carotid endarterectomy in asymptomatic good-risk patients performed by a surgeon whose surgical morbidity and mortality rate is less than 3% are as follows. (1) Proven: none. (As this statement went to press, the National Institute of Neurological Disorders and Stroke issued a clinical advisory stating that the Institute has halted the Asymptomatic Carotid Atherosclerosis Study (ACAS) because of a clear benefit in favor of surgery for patients with carotid stenosis > or = 60% as measured by diameter reduction. When the ACAS report is published, this indication will be recategorized as proven. (2) acceptable but not proven: stenosis > 75% by linear diameter; (3) uncertain; stenosis > 75% in a high-risk patient/surgeon (surgical morbidity and mortality rate > 3%), combined carotid/coronary operations, or ulcerative lesions without hemodynamically significant stenosis; (4) proven inappropriate: operations with a combined stroke morbidity and mortality > 5%.

Carotid endarterectomy can be safely performed with acceptable mortality and morbidity in patients requiring coronary artery bypass grafts

BACKGROUND

Patients undergoing the placement of coronary artery bypass grafts (CABG) with hemodynamically significant carotid artery lesions pose a difficult problem for both cardiac and vascular surgeons. Despite numerous studies, there has been no consensus of opinion as to the proper management of these patients. In numerous series, the combined mortality and perioperative stroke rates in concomitant carotid endarterectomy and CABG procedures have ranged from 8% to 40%. This has made many surgeons consider staging these procedures.

METHODS

Retrospective analysis of patients undergoing combined carotid endarterectomies and CABG from 1980 to 1993 were reviewed. Two hundred six procedures were performed in 189 patients. Seventeen patients had bilateral carotid endarterectomy performed with CABG. The average age of our patient population was 66 years, with 123 being male and 66 being female. Seventy-five percent of the patients were asymptomatic with the remainder having transient ischemic attacks, amaurosis fugax, or prior stroke.

RESULTS

Operative mortality was 2%, with three of four patients dying of cardiac failure and one of a stroke. A temporary neurologic deficit was seen in 2% of patients, and a permanent neurologic deficit was seen in 2 of 206, or 1%. Thirty shunts were used in this series, mostly in patients with contralateral carotid occlusion. All procedures were performed under general anesthesia with full invasive monitoring. One patient was re-explored for bleeding, and one patient had a temporary hypoglossal palsy. A total of 203 cases had the arteriotomies closed primarily, and 3 required patches.

CONCLUSION

In our experience, simultaneous carotid endarterectomy and CABG can be performed with an acceptable mortality and morbidity and does not appear to put the patient at an increased risk. Staging of these procedures may not be necessary in most cases.

Ischemic and hemorrhagic stroke in patients on oral anticoagulants after reconstruction for chronic lower limb ischemia

BACKGROUND AND PURPOSE

Information on the long-term fate of patients with chronic lower limb ischemia is limited. We investigated the long-term risk of the first ischemic and hemorrhagic cerebral stroke in patients on long-term anticoagulant therapy after reconstruction for chronic limb ischemia.

METHODS

In a retrospective study, 376 consecutive patients were seen at regular intervals according to a standard protocol. Only 3 (0.7%) were lost during follow-up (mean duration, 5.9 years). Anticoagulation was with coumarin derivatives followed by prothrombin times periodically. Primary end points were ischemic and hemorrhagic cerebral stroke events, which were confirmed by CT scan, autopsy, or operation in 85% of the cases. Major vascular events were analyzed as a composite secondary end point. The influence of several clinical variables on these outcome events was evaluated in univariate and multivariate analyses.

RESULTS

Thirty-nine patients (10%) had 41 stroke events (23 ischemic, 18 hemorrhagic); 22 of these patients (56%) died from stroke. The cumulative ischemic stroke risk was 5% at 5 years and 12% at 15 years. Prior myocardial infarction was the only independent predictor (relative risk [RR], 3.1; P < .05). The cumulative hemorrhagic stroke risk was 3% at 5 years and 17% at 15 years. Systolic hypertension (RR, 4.8; P < .01) and insulin-dependent diabetes mellitus (RR, 5.4; P < .01) were significant and independent predictors. The risk for a major vascular event was 29% at 5 years and increased to 56% at 15 years. Independent predictors were advanced age (RR, 1.4; P < .005), insulin-dependent diabetes (RR, 2.2; P < .005), and prior myocardial infarction (RR, 1.8; P < .01).

CONCLUSIONS

Patients with chronic lower limb ischemia, notably those with prior myocardial infarction, are at high risk for ischemic stroke. Those with systolic hypertension or insulin-dependent diabetes mellitus are at high risk for hemorrhagic stroke.

Advanced carotid disease in patients requiring aortic reconstruction

Perioperative stroke is a devastating complication of abdominal aortic operations. Patients requiring aortic reconstruction with advanced carotid occlusive disease pose a particularly challenging management problem regarding timing of operations. All patients (n = 121) undergoing both carotid artery endarterectomy (CEA) and abdominal aortic reconstruction (AAR) within 1 year of each other between 1979 and 1989 were reviewed. The sequence of operation was analyzed to determine its effect on early and late outcome. CEA was the first operation in 99 patients (group I); AAR was performed first in 22 patients (group II). Age, gender, number, types of risk factors, and associated medical problems were similar in both groups. Indications for CEA were: transient ischemic attacks (TIAs), recent ipsilateral stroke, or high-grade asymptomatic carotid artery stenosis exceeding 80%. Indications for aortic operation included: abdominal aortic aneurysm, aortoiliac occlusive disease, and combined aortic and renovascular disease. There were five perioperative strokes, two in group I (2%) and three in group II (14%) (p < 0.04). All strokes occurred after AAR. There were five perioperative deaths (4%), four in group I (4%) and one in group II (5%). Overall survival was significantly greater in group I compared to group II (p < 0.04); 5-year survival was 77% and 51%, respectively. Multivariate analysis demonstrated age, hypertension, and diabetes to adversely affect survival; CEA as the first procedure, however, had a protective effect. Importantly, eight strokes occurred in group I in late follow-up, but only one was ipsilateral to the CEA. We conclude that CEA in selected patients who require AAR is safe, and, when performed prior to abdominal aortic repair, reduces perioperative stroke and may improve long-term survival.

The intra-aortic balloon pump, a novel addition to staged repair of combined symptomatic cerebrovascular and coronary artery disease

Five patients with severe symptomatic carotid and coronary artery disease were treated with staged carotid endarterectomy and coronary artery bypass grafting (CABG) under the protection of an intra-aortic balloon pump (IABP) over a 56-month period. All patients presented with unstable angina and multiple ipsilateral transient ischemic attacks. Two of the four patients had four previous myocardial infarctions. Arteriography demonstrated three-vessel coronary artery disease and 80% to 95% stenosis of the ipsilateral internal carotid artery in all patients. An IABP was placed prior to uneventful carotid endarterectomy performed with vein patch angioplasty (three patients) or primary closure (two patients) under general anesthesia. All five patients had remarkably stable blood pressure and cardiac outputs while on the IABP. Twenty-four hours after carotid endarterectomy the patients underwent uneventful CABG of three or more vessels. No complications occurred with either surgical procedure. One patient required femoral embolectomy and repair of a small false femoral aneurysm following removal of the IABP. All patients were discharged home 7 to 13 days after CABG. This initial report suggests that IABP can be used safely in staged operations for carefully selected patients with unstable angina and severe symptomatic carotid artery disease.

Combined carotid and coronary revascularization: the preferred approach to the severe vasculopath

The timing of carotid endarterectomy (CEA) and coronary revascularization (CABG) for concomitant disease is controversial. Results of combined CEA/CABG in 127 patients (age range, 46 to 82 years; mean age, 65 years; 61% male) from 1978 to 1991 were reviewed. Ninety-five patients (75%) were in New York Heart Association functional class III or IV, 48 (38%) had left main coronary artery disease, and 32 (28%) had depressed ejection fraction ( < 0.50). Forty (32%) had asymptomatic bruits, 61 (48%) transient ischemic attacks, and 26 (20%) prior strokes. Seventy-five (59%) had bilateral carotid stenosis, including 20 (16%) with contralateral occlusions. Perioperative mortality was 7 of 127 (5.5%), and all deaths were cardiac related. Myocardial infarctions occurred in 6 of 127 patients (4.7%) and were nonfatal in 3 (2.3%). Permanent strokes occurred in 7 of 127 (5.5%) and were ipsilateral in 5 (3.9%). Perioperative stroke did not occur in the asymptomatic group, but the risk was higher in those with prior stroke (19%) or with contralateral carotid occlusion (15%). The stroke risk for our patients with carotid disease having CABG without CEA is not known, but the literature reports rates as high as 14%. For our patients without known concomitant disease, the risk of permanent stroke was 1.0% (31/3012) for isolated CABG and 1.5% (7/482) for isolated CEA. The late results after CEA/CABG revealed a 5-year survival of 70% +/- 5%, which correlated with ejection fraction ( > or = 0.50, 81% +/- 5%; < 0.50, 45% +/- 11%; p < 0.003). Freedom from late permanent ipsilateral stroke was 97% +/- 2% at 8 years. Freedom from stroke at 5 years was lower among patients with a previous stroke (71% +/- 10%) compared with transiently symptomatic (90% +/- 4%) and asymptomatic (96% +/- 4%) patients (p < 0.03). Combined CEA/CABG is a useful option in this high-risk group of patients with extensive atherosclerosis; avoids a subsequent hospitalization, anesthetic, and delay period; and provides long-term protection from ipsilateral stroke.

Synchronous operation for ischemic cardiac and cerebrovascular disease: early results and long-term follow-up

The late follow-up of 230 patients who underwent synchronous operation for extensive, obstructive extracranial and coronary artery disease from 1974 to 1989 was analyzed. Mean age at operation was 62.5 years; 161 patients (70%) were in New York Heart Association class III or IV, 185 (80%) had triple-vessel disease, and 67 (29%) had left main stem lesions of 50% or more. Previous myocardial infarctions were present in 132 patients (57%). Only 78 had normal left ventricular function. Included were 16 patients undergoing coronary reoperations, 17 patients with additional cardiac procedures, and 3 with synchronous pulmonary procedures. Symptomatic extracranial vascular disease or stabilized neurological deficits were present in 108 patients. Bilateral hemodynamically significant carotid disease was present in 91 patients and arch vessel lesions in 37. The hospital mortality in 8 patients (3.5%) was due to cardiac (n = 4), neurological (n = 1), or multiorgan failure (n = 3). Operative morbidity was mainly neurological (n = 20, 8.7%): 7 reversible deficits and 7 major strokes occurred, 2 reversible and 5 major strokes were related to the operated side(s), and 4 postoperative myocardial infarctions occurred. Actuarial survival at 5 years was 74% (+/- 3.3), at 10 years 54% (+/- 4.9), and at 15 years, 35% (+/- 6.6). This was mainly determined by late cardiac death (41/66). Late morbidity was mainly attributable to cardiac causes rather than neurological causes. At 5 and 10 years, respectively, 72% and 44% of the patients were free of major cardiac and neurological events or death. Synchronous revascularization can be performed relatively safely. The long-term outcome is determined by the extent and severity of the cardiovascular disease.

Perioperative stroke. Part I: General surgery, carotid artery disease, and carotid endarterectomy

Although stroke, defined as a focal neurological deficit lasting more than 24 hr, is uncommon in the perioperative period, its associated mortality and long-term disability are high. No large-scale data are available to identify the importance of recognized risk factors for stroke in the perioperative period. A review of the literature shows that the incidence and mechanism of its occurrence are influenced by the presence of cardiovascular disease and the type of surgery. The most common cause of perioperative stroke is embolism. In non-cardiac surgery, the incidence of perioperative stroke is higher among the elderly. Properly administered, controlled hypotension is associated with minimal risk of stroke. Cerebral vasospasm may be the cause of focal cerebral ischaemia in eclamptic patients, and the aggressive treatment of hypertension may exacerbate the neurological damage. The risk of stroke associated with carotid endarterectomy is closely related to the preoperative neurological presentation, and the experience of the surgical/anaesthetic team. Symptomatic cerebrovascular disease, acute stroke, asymptomatic carotid lesions, preoperative assessment of risk, local and general anaesthesia, cerebral protection and monitoring during carotid endarterectomy are discussed with reference to reducing the risk of perioperative stroke. Adequate monitoring and protection have minimized the risk of ischaemia from carotid clamping, and the major mechanism of stroke is embolization.

The role of carotid screening before coronary artery bypass

Five hundred thirty-nine patients with no symptoms of cerebral ischemia undergoing coronary artery bypass were preoperatively evaluated for presence of carotid stenosis by noninvasive methods (duplex scanning and ocular pneumoplethysmography-Gee). Overall prevalence of carotid stenosis greater than 75% was higher (8.7%) than that generally reported. Age greater than 60 years was significantly related to presence of carotid stenosis greater than 75% (11.3% vs 3.8%, p = 0.003). Risk factors such as hypercholesterolemia, hypertension, diabetes mellitus, and smoking were not predictive for carotid stenosis, postoperative stroke, or death. Carotid stenosis greater than 75% (odds ratio 9.87, p less than 0.005) and coronary artery bypass redo (odds ratio 5.26, p less than 0.05) were both independent predictors of stroke risk. Patients were divided into four groups: group 1, minimal or mild degree of carotid stenosis (less than 50%), not submitted to prophylactic carotid endarterectomy (432 patients, 80.1%); group 2, moderate degree of stenosis (50% to 75%), no prophylactic carotid endarterectomy (60 patients, 11.2%); group 3, severe carotid stenosis; (greater than 75%), submitted to prophylactic carotid endarterectomy (19 patients, 3.5%), group 4, severe carotid stenosis (greater than 75%) no prophylactic carotid endarterectomy (28 patients, 5.2%). Patients in group 4 had significantly higher stroke rate (14.3%) compared to the other three groups (1.1%) (p = 0.0019). The finding of carotid stenosis greater than 75% in patients over 60 years of age was associated with occurrence of stroke in 15% of cases. Carotid screening is helpful to determine patients at increased risk of stroke and should be performed in patients greater than 60 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Therapy for isolated, low and high grade symptomatic carotid artery stenosis

This study evaluates whether medical therapy alone can achieve satisfactory results in the treatment of low grade carotid stenosis or ulcerated plaques. Out of 525 patients presenting with transient or minor strokes, 64 were found with unilateral extracranial vascular disease as the sole potential source for their neurological symptoms. Utilizing arteriographic criteria, 35 patients with ulcerated plaques or carotid artery stenosis of less than 50% luminal artery diameter were treated conservatively with aspirin and dipyridamole (300 mg/day each). Twenty-nine patients with unilateral internal carotid artery stenosis of greater than 50% luminal artery diameter were treated by means of carotid endarterectomy. Follow-up in the two groups for a mean period of 24-26 months revealed no major strokes or neurological deaths in either group. Myocardial infarction was the major cause of death. Two patients developed subsequent transient ischemic attacks, and one a minor stroke with total recovery in the conservatively treated group. All became asymptomatic when warfarin replaced aspirin therapy. The findings in this study confirmed that "low grade" stenoses can be safely treated by medical measures alone.

Early and late results in patients with carotid disease undergoing myocardial revascularization

A ten-year review of 1,360 patients undergoing coronary artery bypass grafting (CABG) by the same surgeon was undertaken. Sixty-two patients with symptoms of coronary artery insufficiency underwent carotid endarterectomy prior to or at the time of CABG (Group I). Ninety-seven patients had asymptomatic carotid bruits but did not undergo carotid endarterectomy (Group II). Sixty of these patients were studied by ultrasonic duplex scanning or ocular pneumoplethysmography or both, and hemodynamically significant stenosis was detected in 50 (Group IIa). Group III included 80 patients without carotid artery disease matched with Group II for sex, age, and clinical status. Group IV consisted of 200 patients without carotid artery disease randomly selected from our series. Follow-up ranged from 3 to 120 months (median, 41 months). In patients with proven carotid artery disease (Groups I and IIa), operative mortality was greater than in the patients randomly selected (Group IV) (p less than 0.05) but similar to that in the matched Group III. Late neurological deficits were greater in patients with carotid disease not undergoing carotid endarterectomy (p less than 0.01). Patients with carotid artery disease had lower survival than Group IV patients (p less than 0.01) but similar survival to that in the matched Group III. This study suggests that (1) asymptomatic patients with carotid artery disease who undergo CABG are not at increased risk of perioperative stroke; (2) these same patients are at increased risk of late neurological deficit; and (3) carotid artery disease is an indirect sign of severe associated disease and therefore is associated with increased operative mortality and decreased life expectancy.

Asymptomatic carotid disease in patients undergoing major cardiovascular operations: can prophylactic endarterectomy be justified?

This article reviews the published experience supporting or refuting the value of prophylactic endarterectomy in patients with asymptomatic carotid disease who are candidates for major cardiovascular operations. Reports of 1,483 patients subjected to staged or concomitant carotid endarterectomy and coronary artery bypass grafting reveal a perioperative stroke rate of 2.9%. Timing of carotid endarterectomy did not influence stroke rate, but staged procedures were associated with a significantly greater incidence of perioperative myocardial infarction and death. Studies of patients undergoing major cardiovascular surgical operations without prophylactic carotid endarterectomy reported a perioperative stroke rate of 2.7%, which is not significantly different from that of patients undergoing prophylactic carotid endarterectomy. However, the author's prospective study of such patients showed a significant incidence of late postoperative neurologic deficits, which are usually transient ischemic attacks. There is no evidence to justify routine prophylactic carotid endarterectomy of asymptomatic carotid disease before major cardiovascular operations. Patients not undergoing endarterectomy, however, should be given careful postoperative follow-up, because transient ischemic attacks may occur that require surgical intervention.