Endograft Treatment in Ruptured Abdominal Aortic Aneurysms Using the Talent® AUI Stentgraft System. Design of a Feasibility Study∗∗

OBJECTIVES

To study the outcome of patients with ruptured AAA treated by EVAR using the Talent AUI stentgraft system.

DESIGN

A multicenter prospective consecutive patient cohort of 100 patients.

MATERIALS

Consecutive patients with ruptured AAA will be screened for treatment by EVAR. All patients screened, including those excluded from EVAR, will be clustered and called the study group. The study group will be compared with a historical group of patients with ruptured AAA derived from literature. The New ERA study started February 2003.

OUTCOME

Main outcome events are applicability rate and operative mortality rate of the study group.

CONCLUSION

The study rationale and design are reported here.

Does gender influence outcome of AAA endoluminal repair?

BACKGROUND

It has been suggested that female patients have a less favourable outcome of endoluminal repair of abdominal aortic aneurysms. Yet, data on stratified per gender are lacking.

METHODS

We reviewed our prospective database of 402 endografts over a 4-year period and the peri- and postoperative course in the 25 (6%) female patients was compared with the 377 (94%) male patients. Median follow-up was 24 months (range 1-56 months). Logistic regression analysis was performed to test the effect of five confounding variables (gender, age, ASA grade IV, EUROSTAR class D or E, AAA diameter) on failure of AAA exclusion.

RESULTS

There were no perioperative deaths in the female group and 5 (1.3%) in the male group (p = 0.8). Major perioperative morbidity occurred in 17% versus 6% (OR 3.7; 95% CI 1.2-10.6; p = 0.026). There were 1 (4%) and 5 (1%) conversions to open repair in the female and male groups, respectively (p = 0.3). Late failure of AAA exclusion occurred in 5 (21%) and 26 (7%) patients, respectively (p = 0.03). Of the five variables examined for their influence on failure of AAA exclusion, female gender (hazard ratio 4.42; 95% CI 1.4-13.4; p = 0.009) and AAA diameter (hazard ratio 1.05; 95% CI 1.009-1.09; p = 0.017), were positive independent predictors of late failure of AAA exclusion on multivariate analysis.

CONCLUSION

Endoluminal AAA repair in female patients appear associated with a less favorable outcome when compared to their male counterparts. These data may be taken into consideration when endoluminal AAA repair is suggested to a female patient.

Endovascular treatment of a postlaminectomy arteriovenous fistula. A case report

We report a case of iliac arteriovenous fistula (AVF) following disk surgery. A 51-year-old woman underwent hemilaminectomy for a slipped disk. Two weeks after surgery the patient experienced dyspnea and oedema of the lower limbs. Presence of a systolic murmur on the cardiac floor and on the abdomen was detected and abdomen CT scan which evidenced a AVF between the right common iliac artery and vein. The lesion, confirmed by angiography, was successfully treated with the endovascular technique. The endovascular technique appears to be a valid alternative to the traditional surgical treatment of postlaminectomy AVF.

Does the presence of an iliac aneurysm affect outcome of endoluminal AAA repair? An analysis of 336 cases

OBJECTIVE

To determine whether the presence of an iliac aneurysm compromises outcome of endovascular exclusion of AAA and to ascertain the fate of the iliac aneurysmal sac.

PATIENTS AND METHODS

Between April 1997 and March 2001, data on 336 consecutive patients undergoing endovascular repair for AAA were entered in a prospective database. Suitability for endovascular repair was assessed by preoperative contrast-enhanced computed tomography. A maximum common iliac artery (CIA) diameter > or = 20 mm was defined as iliac aneurysm. Patients with and without iliac aneurysms were compared to early (immediate conversion or perioperative death) and late failure (increase in aneurysm diameter or persisting graft-related endoleak, or late AAA rupture or conversion).

RESULTS

Fifty-nine patients (18%) had iliac aneurysms, 19 were bilateral, for a total of 78 aneurysmal iliac arteries (median diameter 23 mm; range 20-50 mm). A distal seal was achieved by landing in 33 external iliac arteries, in 20 ectatic CIAs, and in 25 normal CIAs. Operating time differed significantly between patients with and without CIA aneurysms (153 +/- 71 vs 123 +/- 55 min, p = 0.0001), whereas no statistically significant differences were found with respect to early and late failure (2% vs 3%, p = 0.5 and 14% vs 8%, p = 0.11, respectively). There were no cases of buttock or colon necrosis. At a median follow-up of 14 months (range 0-46; i.q.r. 7-27 months) common iliac diameter decreased > or = 2 mm in 49 cases, remained stable in 25, and increased > or = 2 mm in 3.

CONCLUSION

The presence of iliac aneurysm rendered endoluminal AAA repair more complex but did not affect feasibility and long-term outcome of the procedure. In our experience internal iliac exclusion was never associated with significant morbidity. These data may be useful when considering endovascular repair in high-risk patients with challenging anatomy.

Eversion vs conventional carotid endarterectomy: a systematic review

OBJECTIVE

to determine whether eversion carotid endarterectomy (CEA) was safe and more effective than conventional CEA.

METHODS

controlled trials comparing eversion vs conventional technique for CEA were identified from the Cochrane Stroke Review Group database plus additional hand searching. Researchers were contacted to identify additional published and unpublished studies. Randomised and pseudorandomised trials comparing eversion to conventional techniques in patients undergoing CEA were examined. Outcomes included stroke and death, carotid restenosis/occlusion, and local complications.

RESULTS

five trials were included comprising 2465 patients and 2590 arteries. There were no significant differences in the rate of perioperative stroke or death (1.7% vs 2.6%, odds ratio [OR] 0.44, 95% confidence interval [CI] 0.10-1.82) and stroke during follow-up (1.4% vs 1.7%; OR: 0.84; 95% CI: 0.43-1.64) between eversion and conventional CEA techniques. Eversion CEA was associated with a significantly lower rate of restenosis >50% during follow-up (2.5% vs 5.2%, OR: 0.48, 95% CI: 0.32-0.72). There were no statistically significant differences in local complications between the eversion and conventional group. When eversion procedures were compared with patch procedures only, non-significant differences were found in primary outcomes.

CONCLUSIONS

eversion CEA may be associated with low risk of arterial occlusion and restenosis. However, numbers are too small to definitively assess the benefits and disadvantages of eversion CEA. Reduced restenosis rates did not appear to be associated with clinical benefit in terms of reduced stroke risk, either perioperatively or later. Until further evidence is available, the choice of the CEA technique should be based on the experience and familiarity of the individual surgeon.

Endovascular Abdominal Aortic Aneurysm Repair in High-risk Patients: a Single Centre Experience

OBJECTIVES

to evaluate the role of endovascular repair (ER) of abdominal aortic aneurysm (AAA) repair in American Society for Anaesthesiology [ASA] class IV patients.

PATIENTS AND METHODS

between April 1997 and March 2000, 266 consecutive patients underwent ER for AAA. There were 26 patients (10%) with ASA grade IV. The remaining 240 patients, ASA grade between I and III (ASA<IV group), were compared with the ASA IV group. Mean follow-up was 11.6 months (range 1-32 months). Increase in AAA diameter after ER or persisting graft-related endoleak were defined as failure of AAA exclusion. Regression analysis was performed to test the effect of five confounding variables on failure of AAA exclusion and perioperative mortality.

RESULTS

patients in the ASA IV group were significantly older than patients in ASA <IV group (mean age: 74 years vs 70 years p=0.005). AAA were larger (mean diameter: 56 mm vs 50 mm p =0.002) and more extensive (class E of EUROSTAR classification: 27% vs 5.8% p =0.002). There were two perioperative deaths in the ASA IV group and one in the ASA<IV group (8% vs 0.4%; RR 19; 95% CI 1.8-202 p=0.01). Major perioperative morbidity occurred in 8% of patients in the ASA IV group and in 3.3% in the ASA<IV group (n.s.). There were no conversions to open repair in the ASA IV group while six were performed in the ASA<IV group (n.s.). Length of hospitalisation was significantly longer for patients in the ASA IV group: 7.8 days vs 3.2 days (p =0.001). Operative times and blood loss were similar. Failure of AAA exclusion occurred in two patients (8%) in the ASA IV group and in four patients (1.6%) in the ASA<IV group (n.s.). On life table analysis, survival rates at 26 months were 76% in the ASA IV group and 89% in the ASA<IV group (p =0.004). Five variables were examined by regression analysis and no independent predictors of failure of AAA exclusion and operative mortality were found.

CONCLUSIONS

ER in ASA IV patients is feasible and effective with acceptable actuarial survival rates. However, the endovascular procedure in these patients is associated with higher major systemic morbidity, mortality, and prolonged hospitalisation rates.

Eversion versus conventional carotid endarterectomy for preventing stroke

BACKGROUND

Carotid endarterectomy is conventionally undertaken by a longitudinal arteriotomy. Eversion carotid endarterectomy (CEA), which employs a transverse arteriotomy and reimplantation of the carotid artery, is reported to be associated with low perioperative stroke and restenosis rates but an increased risk of complications associated with a distal intimal flap.

OBJECTIVES

The objective of this review was to determine whether eversion CEA was safe and more effective than conventional CEA. The null-hypothesis was that there was no difference between the eversion and the conventional CEA techniques (performed either with primary closure or patch angioplasty).

SEARCH STRATEGY

The reviewers searched MEDLINE and the Cochrane Stroke Group Trials Register (last searched: December 1999), and hand searched eight surgical journals and conference proceedings. Researchers were contacted to identify additional published and unpublished studies.

SELECTION CRITERIA

All randomised trials comparing eversion to conventional techniques in patients undergoing carotid endarterectomy were examined in this review. Outcomes were stroke and death, carotid restenosis/occlusion and local complications.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two reviewers to assess eligibility and describe trial characteristics, and by one reviewer for the meta-analyses. Discrepancies were resolved by discussion. When possible, unpublished data were obtained from investigators.

MAIN RESULTS

Five trials were included for a total of 2465 patients and 2590 arteries. Three trials included bilateral carotid endarterectomies. In one trial, arteries rather than patients were randomised so that it was not clear how many patients had been randomised in each group, therefore, information on the risk of stroke and death from this study were considered in a separate analysis. There were no significant differences in the rate of perioperative stroke and/or death (1.7% vs 2.6%, odds ratio [OR] 0.44, 95% confidence interval [CI] 0.10-1.82) and stroke during follow-up (1.4% vs 1.7%, OR: 0.84, 95% CI: 0.43-1.64) between eversion and conventional CEA techniques. Eversion CEA was associated with a significantly lower rate of restenosis >50% during follow-up (2.5% vs 5.2%, OR: 0.48, 95% CI: 0.32 -0.72). However, there was no evidence that the eversion technique for CEA was associated with a lower rate of neurological events when compared to conventional CEA. There were no statistically significant differences in local complications between the eversion and conventional group. No data were available to define the cost-benefit of eversion CEA technique.

REVIEWER'S CONCLUSIONS

Eversion CEA may be associated with low risk of arterial occlusion and restenosis. However, numbers are too small to definitively assess benefits or harms. Reduced restenosis rates did not appear to be associated with clinical benefit in terms of reduced stroke risk, either perioperatively or later. Until further evidence is available, the choice of the CEA technique should depend on the experience and familiarity of the individual surgeon.

Predictive factors for early success of endovascular abdominal aortic aneurysm repair

To identify predictive factors for postoperative success and potential predictors for satisfactory outcome of endovascular grafting for abdominal aortic aneurysm (AAA), we collected data from our prospective database, which includes a series of consecutive patients undergoing endovascular repair at the Vascular Surgery Unit, Policlinico Monteluce, Perugia, Italy. From April 1997 to July 1998, 202 patients were referred to our Unit for elective AAA repair; 94 patients (47%) were selected for endografting. Placement of the graft using endovascular technique without conversion to open laparotomy, in addition to no mortality, major morbidity, or endoleak at 30-day follow-up, was defined as postoperative success. The influence of anatomical features on postoperative results was analyzed by univariate and multivariate analysis. Our experience shows that endoluminal repair of AAA is safe and effective in the short term and male patients with small aneurysms are optimal candidates for successful repair.

Role of duplex scan in endoleak detection after endoluminal abdominal aortic aneurysm repair

OBJECTIVE

to validate the role of duplex scan in endoleak detection in postoperative surveillance of endoluminal abdominal aneurysm repair (EAAR).

PATIENTS AND METHODS

between April 1997 and March 1999, 103 patients were eligible for duplex and computed tomography (CT) scan after EAAR. Mean follow-up was 8 months (range 1-24 months). The study protocol comprised concurrent examination with colour-duplex and CT scan at 1, 6, and 12 months after EAAR, for a total of 198 concurrent examinations. All duplex scan examinations were performed by two vascular surgeons with the same machine (ATL HDI 3000). Interobserver agreement in endoleak detection (kappa=1) and in type of endoleak (kappa=0.7) was evaluated in 50 random duplex examinations. Endoleak detection was examined comparatively in duplex and CT scan, the latter being the gold standard. Sensitivity and specificity tests together with negative- and positive-predictive values (NPV and PPV) were calculated.

RESULTS

duplex scan was not feasible in one patient. On CT scan the endoleak rate was 4% at one month, 3% at 6 months, and 4% at one year. Overall, CT scan detected 12 endoleaks. With respect to endoleak detection, duplex scan revealed a great ability in ruling out false-negative results (sensitivity 91.7%, NPV 99.4%), but overestimated the presence of endoleak (specificity 98.4%, PPV 78. 6%). Regarding type of endoleak, the ability of duplex scan to identify the source of endoleak was low (sensitivity 66.7%).

CONCLUSIONS

duplex scan, if validated, appears to be a reliable means for excluding the presence of endoleak after EAAR.

Eversion versus conventional carotid endarterectomy: late results of a prospective multicenter randomized trial

OBJECTIVE

The durability of carotid endarterectomy (CEA) may be affected by carotid restenosis. The data from randomized trials show that the highest incidence of restenosis after CEA occurs from 12 to 18 months after surgery. The optimal CEA technique to reduce perioperative complications and restenosis rates is still undefined. This study examines the long-term clinical outcome and incidence of recurrent stenosis in patients who undergo eversion CEA. Previously published perioperative results of this study did not show statistically significant differences in study endpoints between the eversion and standard techniques.

METHODS

From October 1994 to March 1997, 1353 patients with surgical indications for carotid stenosis were randomly assigned to undergo eversion (n = 678) or standard CEA (n = 675; primary closure, 419; patch, 256). Withdrawal from the assigned treatment occurred in 1.6% of the patients (in 13 assigned to eversion CEA, and in nine assigned to standard CEA). The clinical and duplex scan follow-up examination was 99% complete, and the mean follow-up interval was 33 months (range, 12 to 55 months). The primary outcomes were perioperative and late major stroke and death, carotid restenosis (stenosis >/= 50% of the lumen diameter detected at duplex scanning), and carotid occlusion. The primary evaluation of study outcomes was conducted on the basis of an intention-to-treat analysis.

RESULTS

Restenosis was found at duplex scanning in 56 patients (19 in the eversion group, and 37 in the standard group). Within the standard group, the restenosis rates were 7.9% in the primary closure population and 1.5% in the patched population. Of the patients with restenosis, 36% underwent cerebral angiography that confirmed restenosis in all cases. The cumulative restenosis risk at 4 years was significantly lower in the group that underwent treatment with eversion CEA as compared with the standard group (3.6% vs 9.2%; P =.01), with an absolute risk reduction of 5. 6% and a relative risk reduction of 62%. Eighteen patients would have had to undergo treatment with eversion CEA to prevent one restenosis during the 4-year period. The incidence rate of ipsilateral stroke was 3.3% in the eversion population and 2.2% in the standard group. There were no significant differences in the cumulative risks of ipsilateral stroke (3.9% for eversion, and 2.2% for standard; P =.2) and death (13.1% for eversion, and 12.7% for standard; P =.7)) in the two groups. Of the 18 variables that were examined for their influence on restenosis, eversion CEA (hazard ratio, 0.3; 95% confidence interval, 0.2 to 0.6; P =.0004) and patch CEA (hazard ratio, 0.2; 95% confidence interval, 0.07 to 0.6; P =. 002) were negative independent predictors of restenosis with multivariate Cox proportional hazards regression analysis.

CONCLUSION

The EVEREST (EVERsion carotid Endarterectomy versus Standard Trial) showed that eversion CEA is safe, effective, and durable. No statistically significant differences were found in late outcome between the eversion and standard techniques at the available follow-up examination.

Epidural anesthesia reduces length of hospitalization after endoluminal abdominal aortic aneurysm repair

PURPOSE

The low invasiveness of endoluminal abdominal aneurysm repair (EAAR) appears optimal for the use of epidural anesthesia (EA). However, reported series on EAAR show that general anesthesia (GA) is generally preferred. To evaluate the feasibility and problems encountered with EA for EAAR, patients undergoing EAAR with EA and patients undergoing EAAR with GA were examined.

METHODS

From April 1997 through October 1998, EAAR was performed on 119 patients at the Unit of Vascular Surgery at Policlinico Monteluce in Perugia, Italy. Four patients (3%) required conversion to open repair and were excluded from the analysis because they were not suitable candidates for evaluating the feasibility of EA. The study cohort thus comprised 115 patients undergoing abdominal aortic aneurysm (AAA) repair with the AneuRx Medtronic stent graft. The incidence of risk factors and anatomical features of the aneurysm were compared in patients selected for EA or GA on the basis of intention-to-treat analysis. Intraoperative and perioperative data were compared and analyzed on the basis of intention-to-treat and on-treatment analysis.

RESULTS

Sixty-one patients (54%) underwent the surgical procedure with EA (group A), and 54 (46%) underwent the surgical procedure with GA (group B). Conversion from EA to GA was required in four patients (3 of 61 patients, 5%). There were no statistically significant differences between the two study groups in demographics, clinical characteristics, and American Society of Anesthesiology classification (ASA). There was no perioperative mortality. Major morbidity occurred in 3% of patients (group B). According to intention-to-treat analysis, no significant differences were observed between the two groups in mean operating time, fluoro time, blood loss, amount of contrast media used, mean units of transfused blood, need of intensive care unit, mean postoperative hospital stay, and postoperative endoleak. Conversely, significant differences were found by means of on-treatment analysis in the need of intensive care unit (0 vs 5 patients; P =.02), and length of hospitalization (2.5 vs 3.2 days; P =.04). Multivariate logistic regression analysis showed that GA and ASA 4 were positive independent predictors of prolonged (more than 2 days) postoperative hospitalization (hazard ratio, 2.5; 95% CI, 1.1 to 5.8; P =.03, and hazard ratio, 5.1; 95% CI, 1.5 to 17.9; P =.007, respectively).

CONCLUSION

EA for EAAR is feasible in a high percentage of patients in whom it is attempted, and it ensures a technical outcome comparable with that of patients undergoing EAAR with GA. Successful completion of EAAR with EA is associated with a short period of hospitalization.

Intraoperative assessment of technical perfection in carotid endarterectomy: a prospective analysis of 1305 completion procedures. Collaborators of the EVEREST study group. Eversion versus standard carotid endartectomy

OBJECTIVE

to define the incidence of technical defects and the impact of technical errors on ipsilateral carotid occlusion, ipsilateral stroke, and early restenosis rates, we analysed 1305 patients undergoing carotid completion procedures.

DESIGN

prospective multicentre study.

PATIENTS AND METHODS

adequacy of CEA was assessed intraoperatively by angiography in 1004 (77%), by angioscopy in 299 (22%), and by duplex scan in two patients (1%). Arteriograms and angioscopic findings were interpreted at the time of the procedure by the operating surgeon, who also established the need for immediate surgical revision.

RESULTS

perioperatively, 13 major strokes (0.9%, all ipsilateral) and six deaths (0.4%) were recorded. Overall, 112 defects (9%) were identified intraoperatively: 81 (72%) were located in the common carotid artery (CCA) or internal carotid artery (ICA), and 31 (28%) in the external carotid artery. In 48 patients (4%) the defects were revised. Logistic regression analysis revealed that carotid plaque extension >2 cm on the ICA was a positive independent predictor of CEA defects (odds ratio (OR) 1.5p=0.03). A significant association was found between the incidence of revised defects of the CCA and ICA and perioperative ipsilateral stroke (OR 11.5p=0.0002). In contrast, patients with minor non-revised defects had an ipsilateral stroke rate comparable to that of patients with no defects (p=0.4). No significant association was found between revised or non-revised defects and occurrence of restenosis/occlusion at 6-month follow-up.

CONCLUSIONS

the incidence of major technical defects during CEA is low, yet the perioperative neurological prognosis of patients with major defects warranting revision is poor. Completion angiography or angioscopy and possible correction of defects did not protect per se from an unfavourable early outcome after CEA. Therefore, surgical excellence is mandatory to achieve satisfactory results after CEA.

Cerebral tomographic findings in patients undergoing carotid endarterectomy for asymptomatic carotid stenosis: short-term and long-term implications

PURPOSE

Preoperative cerebral imaging has been considered not to be cost-effective in carotid endarterectomy (CEA) for asymptomatic carotid stenosis. Yet, silent brain infarction (SBI) has been associated with the embolization potential of a severe carotid stenosis. Thus the presence of SBI may represent an additional indication for CEA in asymptomatic patients. We examined the predictive value of preoperatively detected silent cerebral lesions on early and late outcomes in patients undergoing CEA for asymptomatic carotid stenosis.

METHODS

Preoperative cerebral tomographic (CT) scans performed on 301 asymptomatic patients undergoing 346 CEAs from 1986 to 1995 were reviewed by a single neuroradiologist blinded to patients' records. Mean follow-up was 67. 3 months (range, 24-130 months). The degree of internal carotid lumen reduction was measured bilaterally in all patients (602 carotid arteries); carotid stenosis of 60% or more was found in 399 carotid arteries.

RESULTS

Of the 103 (34%) CT scans positive for cerebral lesions, 58% were lacunar. No significant association was observed between the side of the cerebral lesion on CT scan and the severity of the corresponding carotid stenosis; 38 silent lesions were detected in the 203 hemispheres ipsilateral to carotid stenoses that were less than 60% versus 95 SBIs in the 399 hemispheres ipsilateral to carotid stenoses that were 60% or more (19% vs 24%; P =.2). There were no significant differences in the perioperative stroke/death rate in patients with or without cerebral CT lesions (2% vs 1%; odds ratio, 1.94; P =.6). Mortality rate during follow-up was 22% in patients with preoperative SBI and 15% in patients without SBI (P =.1). However, actuarial survival at 10 years was shorter (P =.02) in patients with SBI. Late stroke occurred in 11% of patients with preoperative SBI and in 3% of patients without preoperative SBI (P =.006). Cox regression analysis showed that both preoperative lacunar and nonlacunar infarctions were independent predictors of late stroke (hazard ratio, 3.6; P =.04; and hazard ratio, 7.1; P =.001; respectively).

CONCLUSION

In our experience, preoperative SBI did not occur more frequently in the hemisphere ipsilateral to asymptomatic severe carotid stenosis. Although our study lacks a medically treated control group, our data show that SBI is predictive of poor neurologic outcome in asymptomatic patients undergoing CEA. We conclude that CT before CEA, selectively applied, provides information on long-term neurologic prognosis and that a less aggressive attitude towards CEA in asymptomatic patients with SBI may be justified.

Role of surgical techniques and operative findings in cranial and cervical nerve injuries during carotid endarterectomy

OBJECTIVE

To establish the incidence of cranial and cervical nerve injuries during CEA and their relationship to different surgical techniques and operative findings.

DESIGN

A prospective study.

PATIENTS AND METHODS

From January 1994 to April 1995, 187 consecutive patients undergoing 190 CEAs were evaluated. Pre- and postoperative cranial and cervical nerve assessments were carried out by a single otolaryngologist, blinded to the operative technique and findings. Deficits lasting more than 12 months were defined as permanent. Logistic regression analysis was performed to evaluate the influence of surgical technique, type of anaesthesia, neck haematoma, and plaque extension on the onset of nerve injuries.

RESULTS

Postoperatively, nerve lesions were identified in 51 CEAs (27%) and non-neurological injuries (hemilaryngeal ecchymosis or oedema) causing postoperative dysphonia were present in 80 CEAs (42%). All non-neurological injuries were transient and 98% disappeared within 1 month of surgery. Thirteen (7%) nerve lesions were permanent, but none were disabling. Vagus nerve lesions were significantly associated with long (> 2 cm) carotid plaque (OR = 3.5; CI 1.09-12.37; p = 0.03). Cervical branch lesions were associated with the presence of neck haematoma (OR = 1.9; CI 0.7-4.7; p = 0.05). The incidence of single cranial nerve injuries was higher in patch (OR = 2.7) and eversion (OR = 1.9) procedures than in primary closure. Multiple deficits (2 or more) were most frequent in eversion CEAs (OR = 2.8) and in cases complicated by neck haematoma (OR = 3.8).

CONCLUSIONS

Cranial and cervical nerve lesions during CEA are common. However, our data showed that the majority of local complications are related to transient hemilaryngeal ecchymosis or oedema and, when permanent, are neither clinically relevant nor disabling at 1 year of follow up. Carotid plaque extension and neck haematoma appear to increase the incidence of cranial and cervical nerve lesions during CEA.

A randomized study on eversion versus standard carotid endarterectomy: study design and preliminary results: the Everest Trial

PURPOSE

The EVEREST Trial was designed to determine whether the surgical technique influences the durability and complications of carotid endarterectomy (CEA). The current report focuses on the study design and preliminary results.

METHODS

EVEREST is a randomized multicenter trial. A total of 1353 patients with carotid stenosis requiring surgical treatment were randomly assigned to received standard (n = 675) or eversion (n = 678) CEA. Primary end points included carotid occlusion, major stroke, death, and restenosis rate.

RESULTS

The rate of perioperative major stroke and death (1.3 for each study group) and the incidence of early carotid occlusion (0.6% for eversion vs 0.4% for standard) were similar. No significant differences were found between eversion and standard CEA with respect to incidence of perioperative transient ischemic accident, minor stroke, cranial nerve injuries, neck hematoma, myocardial infarction, or surgical defects as detected with intraoperative quality controls. Clamping time was significantly shorter for eversion CEA compared with patch standard procedures (31.7 +/- 15.9 vs 34.5 +/- 14.4 minutes, p = 0.02). A shunt was inserted in 11% of patients undergoing eversion CEAs and in 16% of patients undergoing standard procedures. Overall 30-day events occurred in 13.3% of the eversion group and in 11.4% of the standard group (p = 0.3). At a mean follow-up of 14.9 months (range, 1 to 38 months), 16 (2.4%) restenoses occurred in the eversion group and 28 (4.1%) occurred in the standard group (odds ratio, 0.56; 95% confidence interval, 0.3 to 1.1; p = 0.08).

CONCLUSION

The preliminary results of the EVEREST Trial suggest that eversion CEA is a safe and rapid procedure with low major complication rates. No significant differences in restenosis rates were observed between eversion and standard CEA at the available follow-up. Longer-term results are necessary to assess whether the eversion technique influences the durability of CEA.

Transcranial Doppler monitoring during carotid endarterectomy: is it appropriate for selecting patients in need of a shunt?

PURPOSE

This report summarizes our experience in evaluating a series of 168 patients who underwent a total of 175 carotid endarterectomy procedures under local anesthesia. Patients were monitored by stump pressure (SP) measurement and transcranial Doppler scanning (TCD). The need for shunting was compared between SP/TCD flow velocity reduction and the awake response (gold standard).

METHODS

The study cohort represented 56% of all the carotid patients treated during the study period. Clamping ischemia was defined as the appearance of focal deficit (focal ischemia) or unconsciousness (global deficit) on carotid clamping. In the case of clamping ischemia, a shunt was inserted. To define the optimal value of SP and TCD flow velocity that is able to discriminate patients with clamping ischemia, a receiver operator characteristic (ROC) curve was constructed. Sensitivity and specificity tests, together with negative and positive predictive values (NPV and PPV), were calculated. Cutoff values were defined as the ROC curve values that correlated the highest sensitivity with the highest specificity for both SP and TCD.

RESULTS

Clamping ischemia was present in 18 procedures (10%) in which a shunt was used. No perioperative deaths were recorded. Major perioperative morbidity occurred in one patient (0.6%). Two nondisabling strokes were also recorded (1.8% overall rate of neurologic morbidity). Cutoff values for both SP and TCD, using the ROC curve, were < or = 50 mm Hg and > or = 70% flow velocity reduction from baseline, respectively. SP values of < or = 50 mm Hg or less showed a sensitivity of 100%, a specificity of 83%, a PPV of 40%, and an NPV of 100%. TCD flow monitoring (> or = 70% flow reduction) revealed a lower sensitivity (83%) but a greater ability to avoid false positive results (96% specificity), resulting in increased PPV (71%) and NPV (98%). Combining SP and TCD failed to provide better results in terms of specificity (81%) and PPV (38%).

CONCLUSIONS

SP measurement using a 50 mm Hg cutoff appears to be a reliable predictor of clamping ischemia but requires the use of a shunt in 17% of the patients who would otherwise not require this procedure. In contrast, TCD has greater specificity but is associated with a lower sensitivity, with 17% false negative results. In our experience, both SP and TCD show limitations, as they overestimate or underestimate carotid endarterectomy procedures in need of a shunt. We believe that sensitivity is more important than specificity in carotid endarterectomy, and thus conclude that TCD flow velocity measurement is not an optimal method for detecting clamping ischemia.

Thoracoabdominal aneurysm repair: perspectives over a decade with the clamp-and-sew technique

OBJECTIVES

Experience over a decade with thoracoabdominal aortic aneurysm (TAA) repair using a clamp-sew technique was reviewed to compare overall results with alternative operative methods.

SUMMARY BACKGROUND DATA

Controversy continues as to the optimal technique for TAA repair, with frequent contemporary emphasis on bypass-distal perfusion methods. Proponents of this technique claim improved results compared to those of historic control subjects in the parameters of operative mortality, postoperative renal failure, and lower extremity neurologic deficit.

METHODS

Over the interval from 1987 to 1996, 160 TAA repairs (type I, 32%; type II, 15%; type III, 34%; and type IV, 19%) were performed in 157 patients with a mean age of 70 years and a male-to-female ratio of 1/1. Clinical features included ruptured TAA (10%), urgent operation (22.5%), and aortic dissection (18%). Operative management used a clamp-sew technique with regional hypothermia for spinal cord (epidural cooling, since 1993) and renal protection. Variables associated with the endpoints of operative mortality or major morbidity, particularly spinal cord injury, were assessed with Fisher exact test and logistic regression; late survival was estimated with the Kaplan-Meier method.

RESULTS

In-hospital mortality was 9% and was associated with operation for rupture (p < 0.005) or other acute presentation (p < 0.001). After multivariate analysis, the postoperative complication renal failure (relative risk, 6.5 [95% confidence interval, 1.8-23.6, p = 0.004]) and significant spinal cord injury (relative risk, 16.5 [95% confidence interval, 3.2-83.2, p = 0.001]) were associated independently with operative mortality. Paraparesis-paraplegia occurred in 7%, an incidence significantly (p < 0.001) less than that (18.7%) predicted for this cohort from published models. Variables associated (univariate analysis) with this complication included TAA rupture (p < 0.0001), other acute presentation or dissection (p < 0.001), prolonged (>6 hours) operation (p < 0.04), and excessive (>3 L) transfusions (p < 0.02). Operation for acute presentation or dissection (relative risk, 7.9 [95% confidence interval, 1.7-37.7, p = 0.009]) and prolonged surgery [relative risk, 7.5 [95% confidence interval, 1.5-35.3, p = 0.01]) retained independent association with paraplegia-paraparesis after multivariate analysis. Dialysis was needed in 2.5%. Late survival at 1 and 5 years was 86 +/- 2.9% and 62 +/- 5.8%, respectively.

CONCLUSIONS

These data compare favorably with those from contemporary reports using other operative strategies and do not support routine adoption of bypass-distal perfusion as the preferred technique for TAA repair.

Clinical experience with epidural cooling for spinal cord protection during thoracic and thoracoabdominal aneurysm repair

PURPOSE

This report summarizes our experience with epidural cooling (EC) to achieve regional spinal cord hypothermia and thereby decrease the risk of spinal cord ischemic injury during the course of descending thoracic aneurysm (TA) and thoracoabdominal aneurysm (TAA) repair.

METHODS

During the interval July 1993 to Dec. 1995, 70 patients underwent TA (n = 9, 13%) or TAA (n = 61) (type I, 24 [34%], type II, 11 [15%], type III, 26 [37%]) repair using the EC technique. The latter was accomplished by continuous infusion of normal saline (4 degrees C) into a T11-12 epidural catheter; an intrathecal catheter was placed at the L3-4 level for monitoring of cerebrospinal fluid temperature (CSFT) and pressure (CSFP). All operations (one exception, atriofemoral bypass) were performed with the clamp-and-sew technique, and 50% of patients had preservation of intercostal vessels at proximal or distal anastomoses (30%) or by separate inclusion button (20%). Neurologic outcome was compared with a published predictive model for the incidence of neurologic deficits after TAA repair and with a matched (Type IV excluded) consecutive, control group (n = 55) who underwent TAA repair in the period 1990 to 1993 before use of EC.

RESULTS

EC was successful in all patients, with a 1442 +/- 718 ml mean (range, 200 to 3500 ml) volume of infusate; CSFT was reduced to a mean of 24 degrees +/- 3 degrees C during aortic cross-clamping with maintenance of core temperature of 34 degrees +/- 0.8 +/- C. Mean CSFP increased from baseline values of 13 +/- 8 mm Hg to 31 +/- 6 mm Hg during cross-clamp. Seven patients (10%) died within 60 days of surgery, but all survived long enough for evaluation of neurologic deficits. The EC group and control group were well-matched with respect to mean age, incidence of acute presentations/aortic dissection/aneurysm rupture, TAA type distribution, and aortic cross-clamp times. Two lower extremity neurologic deficits (2.9%) were observed in the EC patients and 13 (23%) in the control group (p < 0.0001). Observed and predicted deficits in the EC patients were 2.9% and 20.0% (p = 0.001), and for the control group 23% and 17.8% (p = 0.48). In considering EC and control patients (n = 115), variables associated with postoperative neurologic deficit were prolonged (> 60 min) visceral aortic cross-clamp time (relative risk, 4.4; 95% CI, 1.2 to 16.5; p = 0.02) and lack of epidural cooling (relative risk, 9.8; 95% CI, 2 to 48; p = 0.005).

CONCLUSION

EC is a safe and effective technique to increase the ischemic tolerance of the spinal cord during TA or TAA repair. When used in conjunction with a clamp-and-sew technique and a strategy of selective intercostal reanastomosis, EC has significantly reduced the incidence of neurologic deficits after TAA repair.

Coagulation changes during thoracoabdominal aneurysm repair

PURPOSE

The cause of coagulopathic hemorrhage during thoracoabdominal aneurysm (TAA) repair has not been well defined in human studies. We investigated changes in the coagulation system associated with supraceliac versus infrarenal cross-clamping to address this critical issue.

METHODS

Blood levels of fibrinogen, the prothrombin fragment F1.2, D-dimer, and factors II, V, VII, VIII, IX, X, XI, and XII were analyzed in 19 patients with TAAs and four patients with abdominal aortic aneurysms (AAAs) at: (A) induction; (B) 30 minutes into supraceliac (TAA) or infrarenal (AAA) clamping; (C) 30 minutes after release of supraceliac or infrarenal clamps; and (D) immediately after surgery. Preoperative and intraoperative variables, including but not limited to aneurysm type, pathologic findings, comorbid conditions, clamp times, volume and timing of blood products, and clinical outcome, were prospectively recorded. Significance was determined by analysis of variance, Student's t test, and univariate linear regression.

RESULTS

Levels of fibrinogen and factors II, V, VIII, VIII, IX, X, XI, and XII decreased (p < 0.05) at time B versus time A and returned to near baseline by time D. D-dimer and F1.2 increased starting at time B and reached significance (p < 0.05) by time D. Data points were compared for the TAA and AAA groups. Although AAA groups demonstrated a trend to factor activity reduction and increased fibrinolysis, the effect was much less pronounced than in TAA and did not approach significance. No correlation of coagulation change with clamping time was present; however, visceral clamping times were all less than 65 minutes (mean, 44 minutes). Blood and factor replacement was initiated after time B. Univariate regression analysis of factor level versus total blood replacement demonstrated a significant (p < 0.04) correlation between the reduction in the levels of factors II, V, VII, VIII, X, and XII, and the increase in the level of D-dimer at time B and subsequent total blood replacement.

CONCLUSIONS

Thoracoabdominal aneurysm repair is associated with a reduction in clotting factor activity and an increase in fibrinolytic function, which occurs after placement of the supraceliac clamp. Explanations include visceral ischemia or a greater and longer ischemic tissue burden as the likely cause of coagulation alterations. Total blood replacement during TAA procedures was correlated to the degree of factor reduction and fibrinolysis at the time of visceral cross-clamping. An aggressive approach to early blood component replacement and to coagulation monitoring could lessen blood loss during TAA repair and avoid potentially disastrous bleeding complications.

Functional outcome after surgical treatment for intermittent claudication

PURPOSE

Although patency data for lower extremity bypass grafts are readily available, few reports have focused on patients' satisfaction after surgical reconstruction for claudication. We reviewed our experience with surgical treatment for claudication, focusing on late outcome from the patients' perspective to further refine surgical decision making in patients with intermittent claudication.

PATIENTS AND METHODS

From February 1987 through April 1994, 114 consecutive patients underwent surgical bypass for intermittent claudication. Nine patients were lost to follow-up, leaving the study cohort composed of 105 patients with a mean age of 63 years (range 42 to 82 years). Sixty-two percent of the procedures were inflow reconstructions, and the remainder were infrainguinal bypasses. Clinical and demographic data were gathered from record review, and late follow-up was obtained by return visit or telephone interview. Patient satisfaction and level of function were assessed by a simple five-point questionnaire administered by a research nurse. Actuarial methods were used to calculate late graft patency and survival. Cox regression analysis was used to identify clinical and anatomic factors predictive of late survival and favorable outcome.

RESULTS

Cardiac risk assessment revealed that 75% of patients either had no clinical markers for cardiac disease or had been treated with previous coronary artery bypass grafting or percutaneous transluminal angioplasty; despite this 61% of patients underwent specific preoperative cardiac testing. Most (68%) inflow procedures were aortobifemoral bypass grafts, and 93% of outflow procedures were femoropopliteal bypass grafts. Two thirds of infrainguinal grafts were performed with autogenous conduits, with prosthetic femoropopliteal bypass grafts performed only to the above-knee popliteal artery. Early graft failure with successful immediate revision occurred in 5% of patients. No operative deaths or early or late amputations occurred. At a mean follow-up of 4.5 years 96% of surviving patients had a patent graft. However, primary unassisted patency at 4 years was superior for inflow (92% +/- 4%) versus outflow (81% +/- 6%) procedures (p = 0.009). Late readmission for cardiac-related events occurred in 12%, and late cardiac-related death occurred in 5%. Actuarial survival at 5 years was 80% +/- 5%, with diabetes being the only negative survival predictor (risk ratio 2.6, 95% confidence interval 1 to 7, p = 0.049); 60% of late deaths were cancer-related. Satisfactory late results were reported by 82% of patients, with age < or = 70 years (odds ratio 4.01, 95% confidence interval 1.2 to 13.7, p = 0.026) and normalization ( > or = 0.85) of ankle/brachial index (odds ratio 5.7, 95% confidence interval 1.6 to 20, p = 0.008) being powerful independent predictors of patient satisfaction.

CONCLUSIONS

After considering cardiac-related short- and long-term prognosis, we conclude that lower extremity bypass grafting for intermittent claudication will produce optimal results when restricted to younger ( < 70 years) nondiabetic patients in whom near normalization of the postoperative ankle/brachial index can be anticipated.

Carotid endarterectomy contralateral to an occluded carotid artery: a retrospective case-control study

OBJECTIVES

To analyse whether contralateral occlusion represents an additional perioperative risk factor in carotid endarterectomy (CEA), and whether long-term survival after surgery in patients with contralateral occlusion differs from that of patients without.

DESIGN

Retrospective clinical study.

SETTING

Vascular Surgery Unit, Department of Surgery, University of Perugia, Perugia, Italy.

MATERIALS

Fifty-five patients with carotid stenosis and contralateral occlusion undergoing CEA (Group 1) were compared with 110 patients (Group II), without contralateral occlusion selected from a cohort of 367 patients with a patent contralateral artery, matched for gender, age and ipsilateral symptoms.

CHIEF OUTCOME MEASURES

Perioperative stroke/death rate at 30 days and minor complications in Group I vs. Group II over a mean follow-up of 38 months.

MAIN RESULTS

The perioperative stroke/death rate at 30 days was 0% in Group I and 2.7% in Group II (p = 0.6) while minor complications amounted to 11% in Group I and 5% in Group II (p = 0.2). Survival rates of patients free from stroke, using Kaplan Meier curves, were 79.4% in Group I and 83.3% in Group II (p = 0.4); stroke free rates were 92.8% and 94.3% in Groups I and II, respectively. The incidence of late stroke, fatal or not, in patients who had undergone CEA with contralateral obstruction was the same as in similarly operated patients without contralateral obstruction (7% vs. 6%). However, the incidence of late vascular death, exemplified by a crude rate of 14% vs. 6% (p = 0.1; O.R. = 2.50; C.I. = 0.77-8.25) was greater in patients with contralateral occlusion.

CONCLUSIONS

In this study, CEA in patients with contralateral occlusion was not associated with an increased perioperative morbidity/mortality rate. The higher incidence of vascular death in the late follow-up of patients with contralateral carotid occlusion, although not statistically significant, could indicate the presence of more severe systemic vascular disease.

Carotid stenosis and coronary artery disease in the elderly: the vascular surgeon's point of view

Surgical prevention of stroke is justified only when the perioperative morbidity and mortality rates are very low. Therefore, an accurate cardiac evaluation is essential for patients with a vascular disease like carotid stenosis, to reduce the surgical risk and improve prognosis. The aim of our retrospective study was to characterize subgroups of patients with high cardiac risk. From 1986 to 1993 at the Vascular Surgery Unit of the Department of Surgery and Surgical Emergencies at the University of Perugia, 857 carotid endarterectomies were performed on 739 patients. The stroke/death rate, at 30 days after surgery, was 2.16% per patient and 1.86% per procedure; cardiac mortality was 0. However, during follow-up 58 patients died: 55% of these deaths could be attributed to cardiac disease. No statistically significant differences emerged in cardiac mortality of patients with a positive history of cerebral vascular accident with respect to asymptomatics, neither among patients with carotid stenosis associated with complete contralateral occlusion nor among those without. Our group of patients had a 76% survival rate at 7 years after surgery, which is different from that reported by other studies. This may be due to some bias associated with the preoperative selection of the patients and the retrospective nature of our study. Nevertheless, in patients with carotid stenosis, the most important cause of death is cardiac ischemia, therefore a rigorous preoperative selection is mandatory particularly in elderly asymptomatic patients.