Surgery in bilateral carotid arterial lesions

C2ro~a// less carotid artery stenosis. In our patient group (studied from January 1986 to December 1990), 221 patients had surgical treatment for a symptomless carotid stenosis. The perioperative mortality was 1.4% and the post-operative occurrence of strokes was also 1.4%. The results of monitoring the 221 patients over five years showed that 17 died, 4 developed a new neurological deficit, 8 had a remaining carotid stenosis and two a completely occluded artery. In comparison to conservative treatment of carotid stenoses, e.g. using antiplatelet agents which, according to other studies, have a stroke rate of 20%, surgically treated symptomless patients have a markedly smaller chance of suffering a stroke, judged by our unequivocally reduced annual stroke rate. Using a high selective basis of indications for surgical intervention in symptomless carotid stenosis, and taking the perioperative complication rate as well as the documented follow-up complication rate into account, we are of the opinion that far more carotid endarterectomies should be performed in the asymptomatic stage as the number of patients who could profit from this surgery lies far below the number surgically treated every year. 12.6 Combined Carotid Endarterectomy and Coronary Artery Bypass Grafting I.P. FLETCHER and M. VICARETFI, Sydney, Australia Combined carotid endarterectomy (CE) and coronary artery bypass grafting (CABG) was done at the same operation in 46 patients during a period in which 3,487 CABGs and 339 CEs were performed. Forty-four patients had stable or unstable angina and two patients had symptomless coronary artery disease detected by stess testing. Triple vessel disease was present in 29 patients; significant disease in the left anterior descending artery was present in 33 patients. Twenty-nine patients presented with transient ischemic attacks, 12 had nonspecific neurological symptoms and five had asymptomatic carotid stenosis. CE was performed first with a mean carotid clamp time of 34 minutes in 29 patients in whom a shunt was not used. CABG followed CE with a mean number of 4 grafts, mean aortic clamp time of 50 minutes and mean bypass time of 86 minutes. There were two early postoperative deaths of cardiac origin for a mortality of 4.3%. Transient neurological morbidity occurred in three patients (6.5%) but there were no permanent neurological deficits. This study shows that CE can be performed in combination with CABG with minimal neurological morbidity. 12.7 Simultaneous Carotid Entarterectomy/Coronary Artery Bypass Grafting (CEA/CABG) in Patients with Severe Coronary and Carotid Artery Occlusive Disease A.C. CERNAIANU, A.J. DELROSSI, D.R.F. GLUM, T.V. VASSILIDZE, J.H. CILLEY, JR. and M.A. GROSSO, Camden, New Jersey, USA This study assessed the outcome of 11 patients (age 69 + 4 years) with symptomatic, high-grade bilateral carotid stenosis and left main or triple-vessel disease with unstable angina undergoing simultaneous CEA/CABG (7 type II crescendo and 4 type IIl post-myocardial infarction unstable angina). Six had left main and five had triple-vessel disease (mean preoperative EF was 35.3 _+ 6.9%). CEA was followed by CABG (3.2 _ 0.3

CARDIOVASCULAR SURGERY SEPTEMBER 1995

grafts/patient). One patient had additional aortic valve replacement and one had an automatic internal cardiac defibrilator implanted, There was no operative mortality. The overall neurological complication rate was 27.3%. One patient developed perioperative myocardial infarction and one other respiratory failure. Within one year postoperatively, one patient died and three had recurrence of cardio-vascular symptoms. Our data show that simultaneous CEA/CABG in patients with high-risk acute coronary andcerebrovascular insufficiency may result in low mortality, however, a relative increased incidence of short- and long-term morbidity is expected.

12.8 Simultaneous Carotid Endarterectomy and Coronary Artery Bypass A.C. CERNAIANU, D.R. FLUM, T.V. VASSILIDZE, M.A. GROSSO, J.H. CILLEY, R.K. SPENCE and A.J. DELR OSSI, Camden, New Jersey, USA Thirty-eight patients (mean age 69 years) undergoing simultaneous single-stage coronary revascularization and carotid endarterectomy (CEA/CABG) were studied. Thirty-six patients (95%) were in NYHA Class III or IV, 17 (45%) had unstable angina and 7 (18%) were operated on because of evolving myocardial infarction. Previous MI was present in 19 patients (50%). Twenty patients (53%) had neurological symptoms and 27 (71%) had severe bilateral carotid stenosis. Thirty-three (87%) had triple vessel or left main coronary disease. Sequential CEA/CABG was performed in all patients. Four cases had additional cardiac procedures. Operative mortality (5%) was cardiac related. One patient had MI (2.6%). Neurological deficit was present in six (15.8%) with permanent functional impairment in two patients (5.2%). Stroke rate was higher in bilateral carotid stenosis group (23% vs. 10% P = 0.04). Low EF (32 _+ 6% vs. 54 + 2%, P = 0.03) and left main artery disease (34% vs. 6%, P = 0.03) were predictors of postoperative neurological complications. At 37 __- 6 months follow-up there were three deaths. The 5-year life-table survival rate was 87%. Ninety percent of long-term survivors were free from cardiovascular disease symptoms. The outcome of CEA/CABG depends upon the preoperative EF, the extend and location of coronary and carotid artery disease. 12.9 Surgery in Bilateral Carotid Arterial Lesions A. V. PO KR 0 VSKY and D.F. B EL OJAR TSE V, Moscow, Russia Between November 1983 and September 1992, 100 patients with hemodynamically significant atherosclerotic bicarotid lesions were operated on at our institution. 94 patients were male and 6 female with ages from 35 to 68 years (mean 56.2 + 1.3). Nine were symptomless, 22 had TIA, 16 had chronic cerebrovascular insufficiency and 53 had had strokes. 65 patients had multiple lesions of the aortic arch branches. The primary operations performed were: 85 carotid EAE and 15 external carotid artery patching with internal carotid artery resection. In addition, 21 secondary contralateral endarterectomies were performed (19 days to 4 years later). Neurological complications after the primary operations were 7% (4 TIA and 3 strokes with complete resolution) in the periopera-

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22nd World Congressof the InternationalSodety for CardiovascularSurgery tive period. Four patients died due to myocardial infarction. No neurological deficit or deaths were observed in the group with external carotid artery repair. 10-year surveillance of 75 patients showed no neurological events during this period in symptornless patients, 6.3% of the TIA group had TIAs, 20% of stroke in chronic cerebrovascular insufficiency group and 5% of strokes in the group after stroke. 14 patients died during 10-year period: 10 due to myocardial infarction, two after strokes in non-operated vascular beds and from unknown causes. 12.10

Bilateral Asymptomatic Carotid Stenosis Increases Risk of Stroke: Analysis by the CHAT Classification R.W. HOBSON D.G. WEISS andE.F. BERNSTEIN, Newark, New Jersey and LaJolla, Califorma, USA The efficacy of carotid endarterectomy in patients with asymptomatic carotid stenosis continues to be controversial. The results of recent randomized clinical trials have demonstrated benefit for the surgical group in reduction of all neurological events including TIA and stroke as well as stroke alone. The CHAT classification, which was devised to categorize and evaluate subsets of patients, was applied to patients from this randomized clinical trial. Since patients were symptomless for the study arteries at the time of enrollment, this resulted in the assignment of the Co classification. An "H" score was assigned dependent on the presence of prior contralateral symptoms and an appropriate "A" score was based on the entry arteriograms in the 444 adult male patients randomized to carotid endarterectomy plus aspirin (n = 211) versus aspirin therapy alone (n = 233). Pathologic analysis of endarterectomy specimens and CT scans were not included in this clinical trial. The two CHAT factors ("H" and "A") were evaluated for relative risk by Cox regression analysis for the outcomes of stroke alone and stroke and death. Arterial status ("A") was identified as a significant factor for an increase in risk for stroke alone and stroke and death:

(CHA T "A ") Ipsilateral (A) Bilateral (A3) Relative risk

(95% c1)" No of patients 252 Stroke (no %) 19 (7.5%) Stroke & death (no %) 97 (38.5%)

192 26 (13.5%) 93 (48.4%1

1.42 I1.05, 1.93) 0.025 1.25 (1.07, 1.47) 0.004

*Relative Risks, 95% Confidence Intervals, and P-values based on Cox Regression Analysis

Bilateral disease (bilateral stenoses >- 50% and/or unilateral occlusion and ipsilateral stenosis -> 50%) resulted in a significantly increased risk of stroke as well as stroke and death across both medically and surgically managed groups. 12,11

Infection in Carotid Artery Surgery L.G.Y. CLAE.YS, W. REIFFENHA USER and S. HORSCH, Co'logne, Germany Infection is a rare but dreaded complication of operations on the internal carotid artery. The usual presentation of an early

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infection is bleeding. Late infection usually presents as a chronic false aneurysm or abscess. In the presence of prosthetic material, excision of the infected artery or excision of the prosthetic material and reconstruction with an autogenous graft is the therapy of choice. Between January 1986 and December 1993 we performed 2134 carotid endarterectomies in 1785 patients. During follow-up we observed eight early (mean 2 weeks) and one late (4 months) infection. Mean age was 66.9 years. Two patients presented acute bleeding, six as infected hematoma and one patient as a chronic fistula. Seven cases were classified as Szilagy stage II1 and two as Szilagy II. Prosthetic material was present in all of the cases classified as Szilagy 11I. Eight patients had positive cultures (Staphylococcus aureus, Enterobacter, Bacteroides, Fusibacterium and Streptococcus). The therapy of choice was excision of the patch and reconstruction with an autologous venous patch. All infections were successfully treated by specific antibiotic therapy. There was no postoperative mortality. The procedure was complicated with an intreoperative stroke in one patient. We advocate an aggressive approach in wound infection; the management of choice is reconstruction with autogenous material.

12.12 Clamping Ischemia, Threshold lschemia and Delayed Insertion O f T h e Shunt During Carotid Endarterectomy With Patch

G.P. DERIU, D. MILITE, L. FRANCESCHI, D. COGNOLATO, P. FRIGATT1, and F. GREGO, Padua, Italy Shunt insertion (SI) during CEA is mandatory to avoid neurological damage due to clamping ischemia; however SI before plaque removal has many inconveniences (atheroembolism, intimal dissection, difficulty of endarterectomy). The aim of this study is to verify whether and how long SI may be safely delayed to permit plaque removal and ensure perfusion during the other time consuming manoeuvres of CEA (peeling, patch angioplasty). From July 1990 to July 1994, 236 patients underwent 258 CEAs under general anesthesia with EEG continuous monitoring and PTFE patch angioplasty. A Pruitt-lnahara shunt was routinely inserted only after plaque removal. In 186 CEAs without EEG signs of cerebral ischemia the mean clamping time was 10 min (2-37 min). In 76 CEAs with EEG signs of cerebral ischemia it was 7.3 min (3-20 rain). MI patients had normal EEG signals after delayed SI and reperfusion. At awakening we observed only one irreversible neurological deficit (0.39%), in a patient in whom a shunt was inserted after 10 min. These data confirm the rationale of a delayed SI; the cerebral parenchyma may tolerate flow interruption due to carotid clamping (EEG detectable) without neurological deficits for at least 7.3 min. This time is sufficient to perform the most difficult steps of CEA (plaque removal, distal intima checking) allowing SI in a clean operatory field, without risk of atheroembolism, intimal dissection and moreover avoiding technical errors. Finally the shunt allows complementary time consuming steps, such as patch angioplasty, with improvement of both short- and long-term results.

CARDIOVASCULAR SURGERY SEPTEMBER 1995