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Papers by Edwin Beven

Journal of Vascular Surgery, Mar 1, 1992

PubMed, Dec 1, 1982

During a 12-month period of study, 265 patients (mean age 65 years) underwent a total of 314 caro... more During a 12-month period of study, 265 patients (mean age 65 years) underwent a total of 314 carotid endarterectomies for the management of previous transient cerebral ischemia (39%), prior stroke (10%), or severe asymptomatic carotid stenosis (51%). Five patients (1.6%) died within 30 days of operation, but only three deaths (1%) were related to carotid reconstruction. Six patients (1.9%) experienced postoperative strokes, including 1.6% of those with previous transient ischemia, 9.7% of those with prior strokes (P less than 0.02), and 0.6% of those with asymptomatic carotid stenosis before operation. Digital subtraction angiography (DSA) was performed during the same hospital admission following 262 procedures in a group of 214 patients, including all patients who had postoperative neurologic complications. Seven of these operations were limited to external carotid endarterectomy. The internal carotid artery was entirely normal in 239 (94%) of the remaining 255 DSA studies. The external carotid artery was normal on 238 (93%) of 255 DSA examinations, but was occluded on 12 (4.7%). A focal intimal defect corresponding to the apical arteriotomy suture was found in nine internal carotid arteries (3.6%), but these lesions did not appear to be hemodynamically significant. The internal carotid artery contained over 30% stenosis in two patients (0.8%) and was occluded in five (1.9%). Two of these five patients had neurologic complications, but four others with operative strokes had normal angiograms. Asymptomatic postoperative thrombosis of the internal carotid artery was documented in only three patients (1.2%).

Journal of Vascular Surgery, May 1, 1996

To determine whether gender distinctions influence the cardiac risk or survival rates associated ... more To determine whether gender distinctions influence the cardiac risk or survival rates associated with surgical treatment ofinfrarenal abdominal aortic aneurysms (AAAs). Methods: From 1983 to 1988, graft replacement of intact AAAs was performed in 490 men (84%) and in 92 women (16%) who had no history of myocardial revascularization before the discovery of their AAAs. Patients of both genders were comparable with respect to mean age (68 years) and the prevalence of coronary artery disease (CAD) by standard clinical criteria (men, 73%; women, 65%). Preoperative coronary angiography was obtained in 471 of the 582 patients (men, 81%; women, 80%) during this particular study period. Preliminary coronary bypass was warranted on the basis of existing indications in 111 (24%) of these 471 patients (men, 25%; women, 18%), including 104 (31%) of the 337 who had clinical indications of CAD (men, 32%; women, 26%) but only 7 (5.2%) of the 134 who did not (men, 6%; women, 4%). Follow-up data were collected during a mean interval of 53 months (men, 54 months; women, 48 months) and were analyzed by Kaplan-Meier survival analysis and Cox proportional hazards models. Results: Twenty-nine perioperative deaths (5.0%) occurred in conjunction with AAA repair (men, 5.1%; women, 4.3%), and 126 early and late deaths have occurred (men, 22%; women, 22%). Survival rates for the series were found to correlate with age (p < 0.001), the serum creatinine level (p < 0.001), and the coronary angiographic classification (p < 0.001). No significant differences were identified between the gender cohorts. The cardiac mortality rate for AAA resection was only 1.8% in the 111 patients who had preliminary coronary bypass, but five additional perioperative deaths (4.5%) related to renal failure or sepsis occurred in this group. However, 5-year survival rates for patients receiving preliminary bypass (men, 82%; women, 75%) were closely comparable with those for patients found to have only mild to moderate CAD by angiography (men, 86%; women, 82%). Conclusion: We conclude that men and women with AAAs have similar cardiac risks and survival rates associated with surgical treatment. Our results also illustrate that the potential benefit of coronary intervention for severe CAD in patients of either gender must be considered in the context of long-term outcome and the early mortality rate of AAA repair.

Journal of Vascular Surgery, Feb 1, 1988

Twenty-two patients were selected from a group of 33 patients who underwent recombinant human tis... more Twenty-two patients were selected from a group of 33 patients who underwent recombinant human tissue-type plasminogen activator (rt-PA) thrombolysis for thrombosed infrainguinal bypass grafts of the lower extremity and were compared with 38 matched Fatients who had undergone surgical thrombectomy during the same period. The proportion of Persons with diabetes mellitus, smokers, and types of bypass grafts was similar in both groups. More patients in the rt-PA-treated group had hypertension (p = 0.01). To evaluate the different lengths of follow-up, Kaplan-Meier survival analysis was used with a log-rank test to compare the proportion of persons with patent grafts in the two treatment groups. At 30 days, 86% of the rt-PA-treated grafts were still patent compared with 42% of the surgically treated grafts (p = 0.001). When risk factors on the Kaplan-Meier curves were compared, there was no statistical difference with regard to graft patency among the groups. According to simultaneous Cox regression analysis, no risk factor was significantly associated with graft patency. When amputation was evaluated between treatment groups simultaneously with other risk factors in a logistic regression analysis, smoking and age of the graft were marginally significant (p = 0.07), whereas all other factors were clearly not significant. In 91% of the rt-PA-treated patients, a secondary surgical procedure was required to maintain patency of the graft segment. Eighty-nine percent of the surgically treated patients required similar graft revisions. Two patients in the surgical group and one patient in the rt-PA-treated group had major complications. This short clinical experience suggests that better 30-day patency rates and a lower risk of amputation can be achieved when thrombolysis is associated with surgical revision compared with surgical revision alone. (J VASe SURG 1988;7:347-55.) Some questions raised during the past 3 decades regarding the techniques of infusion and appropriate indications for the use of thrombolytic agents for thrombosed peripheral bypass grafts remain unanswered. These questions include: (1) Which patient might likely respond and benefit from thrombolysis? (2) Is local installation of the lyric agent more effec-From the Cleveland Clinic Foundation.

Journal of Vascular Surgery, Mar 1, 1989

American Journal of Surgery, Feb 1, 1983

In a process similar to the deglycerolization of frozen packed red blood cells, shed autologous r... more In a process similar to the deglycerolization of frozen packed red blood cells, shed autologous red blood cells were collected, filtered, centrifuged, and washed with saline solution until the supernatant was clear (Figure 1). The packed red blood cells were then transferred to a standard

Cleveland Clinic Journal of Medicine, Jun 1, 1986

Journal of Vascular Surgery, 1986

Graft replacement was performed for 123 (77%) of 160 popliteal aneurysms evaluated at The Clevela... more Graft replacement was performed for 123 (77%) of 160 popliteal aneurysms evaluated at The Cleveland Clinic from 1952 to 1984, employing autogenous saphenous vein in 58 (36%), polytetrafluoroethylene in 19 (12%), and of historic interest, Dacron (12%) or arterial homograft (16%) in 46. The 10-year cumulative patency (CP) rate was 56% and the limb salvage (LS) rate was 83% following graft replacement, but late results were superior in patients who received vein bypass (CP, 94%; LS, 98%), in those who underwent revascularization before ischemic complications had occurred (CP, 92%; LS, 96%), and in those who recovered both pedal pulses (CP, 64%; LS, 96%). Long-term asymptomatic limbs were restored in 96%, 92%, and 89% of these subsets, respectively, compared with 65% of those receiving other graft materials (p = 0.00003), 59% of those with preoperative ischemic symptoms (p = 0.00001) and 68% of those regaining only an isolated popliteal pulse (p = 0.0326). These data indicate that popliteal aneurysms should be corrected by vein bypass to a patent tibioperoneal segment before spontaneous thrombosis or embolization eliminates the critical outflow bed. (J VAse St3RG 1986; 3:125-34.) Although rupture is an exceedingly unusual complication, popliteal aneurysms represent a distinct risk for extremity ischemia and limb loss because of spontaneous thrombosis or embolization. In perhaps the last large series of popliteal aneurysms collected before the modern era of arterial reconstruction, Gifford, Hines, and Janes 1 described the clinical course of 100 aneurysms in 69 patients followed up for a ,nean of 50 months at the Mayo Clinic before 1953. Twenty-three (34%) of 68 unoperated limbs deteriorate(~ander observation, including 13 (37%) of 35 that previously had been asymptomatic and 16 (76%) of 21 followed up for longer than 5 years. Major amputation eventually was necessary for 23% of untreated extremities and for 38% of those sustaining ischemic complications. Moreover, 19 of a total of 20 amputations in this series were performed above the knee.

Journal of Vascular Surgery, May 1, 1995

This study was undertaken to determine the mortality and morbidity rates associated with abdomina... more This study was undertaken to determine the mortality and morbidity rates associated with abdominal aortic aneurysm (AAA) repair in octogenarians and to identify factors that may influence survival in this age group. Methods: One hundred fourteen patients (mean age 83 years) were admitted consecutively with 106 infrarenal and eight juxtarenal AAAs from 1984 through 1993. Ninety-four AAAs were asymptomatic, whereas 20 patients with symptoms had 11 intact and nine ruptured AAAs. The mean AAA diameter was 6.7 cm. Repair consisted of aortic bifurcation grafts in 77 patients (67%), tube grafts in 35 (31%), and extraanatomic procedures in 2 (2%). A total of 29 patients (25%) had undergone previous coronary artery bypass (24 patients) or transluminal coronary angioplasty (five patients) either incidentally or as a preliminary procedure before resection of their AAAs. Results: The 30-day mortality rate for the entire series was 14%, but it declined from 23%

Annals of Surgery, Apr 1, 1987

Annals of Surgery, Jul 1, 1985

From 1979 to 1983, 1726 carotid endarterectomies were performed at the Cleveland Clinic. During t... more From 1979 to 1983, 1726 carotid endarterectomies were performed at the Cleveland Clinic. During this period, 39 men (mean age, 60 years) and 22 women (mean age, 63 years) required 65 reoperations (3.8%) for correction of recurrent carotid stenosis occurring 3 to 194 months (mean, 42 months) after previous endarterectomy at this center (N = 43) or elsewhere (N = 22). Remedial procedures were necessary because of restenosis demonstrated by routine noninvasive testing in 32 asymptomatic lesions and because of neurologic symptoms in 33 others. The mean recurrence interval was 57 postoperative months for atherosclerosis (N = 37) in comparison to 21 months (p = 0.0007) for myointimal hyperplasia (N = 28), and was 48 months for men in comparison to 31 months for women (p = NS). Hypercholesterolemia appeared to be associated with late atherosclerotic recurrence (p = 0.05), but was not a feature of myointimal hyperplasia. Patch angioplasty (N = 59) or graft replacement (N = 3) was employed during 62 of the 65 reoperations, with a total of two operative deaths (3.1%), one nonfatal stroke (1.5%), and six transient cranial nerve injuries (9.2%). Three unrelated late deaths have occurred within a mean follow-up period of 23 months, but only three patients have experienced subsequent neurologic symptoms.

Journal of Vascular Surgery, May 1, 1986

Eighty-four patients with infected abdominal aortic grafts managed from 1961 through February 198... more Eighty-four patients with infected abdominal aortic grafts managed from 1961 through February 1985 were reviewed. Thirty-three patients had associated aortoenteric fistula formation. Twenty-eight infections (33%) and 13 aortoenteric fistulas (39%) originated at The Cleveland Clinic, yielding an incidence of aortic graft infection a,f 0.77% (28 of 3652 grafts) and aortoenteric fistula formation of 0.36% (13 of 3652: grafts) at this center. Staphylococcus organisms alone or in combination with other organisms were isolated from 34% of the series. Management consisted of graft removal and extra-anatomic bypass in 54 patients (64%), graft removal alone in 14 (17%) patients, partial graft removal and extra-anatomic bypass in seven (8%) patients, and miscellaneous operations in nine (11%) patients. Twenty-three patients (27%) required major amputations, nine of which were bilateral. Life-table analysis yielded 30-day and l-year survival rates of 72% and 42%, respectively. Thirty-day survival of the aortoenteric fist&a subset (49%) was less than that (86%) of the nonaortoenteric fistula subset (p = 0.003). One-year survival of patients treated since 1980 (54%) was superior to that of patients treated before 1980 (31%, p = 0.035). No difference in operative or l-year survival was demonstrated between the group treated with extra-anatomic bypass and subsequent graft removal and another in which both procedures were performed simuhane:ously, although the staged group experienced substantially fewer (p = 0.04) amputations (7%) than the combined group (41%). (J VASC SURG 1986; 3:725-31.) Since the initial experience with abdominal aortic reconstruction more than 30 years ago, many advances have been made in the management of patients who require this procedure. Despite dramatic improvements in antibiotic prophylaxis, synthetic graft materials, and surgical treatment, infection in an abdominal aortic prosthesis remains one of the most serious complications in vascular surgery. Formnately, its incidence is low, approximating 2% in most reported series.'-4 Although it is a rare event, aortic graft infection still is associated with mortality rates ranging from 25% to 75% and with morbidity in the form of amputation in approximately 30% of patients in whom it does occur.'-' Because of the low incidence of graft sepsis in general, most published series of patients have been small and many include patients with infected arterial prostheses that do not involve the aorta. Consequently, it has been difficult to draw statistically valid From the Department of Vascular Surgery, The Cleveland Clinic Foundation.

Annals of Surgery, Feb 1, 1984

Annals of Vascular Surgery, May 1, 1987

Journal of Vascular Surgery, Jul 1, 2001

safety, effectiveness, and utility of carotid reoperations as well as about their appropriate ind... more safety, effectiveness, and utility of carotid reoperations as well as about their appropriate indications. 7,8 Furthermore, with the advent of carotid angioplasty and stenting, some authors have proposed that recurrent carotid stenosis may be more effectively treated with this method rather than with direct surgical reconstruction. 6,9,10 Although the complication rates and the durability of carotid angioplasty and stenting for recurrent carotid stenosis remain to be clearly demonstrated, it seems likely that the results of catheter-based intervention will increasingly be compared with those of reoperations. Consequently, the current study was undertaken to determine the postoperative mortality and stroke rates associated with reoperations for recurrent carotid stenosis at our own center, to document late survival and the stroke rate in these patients, and to identify clinical factors that may influence their ultimate outcome. PATIENTS AND METHODS Using the computerized registry of the Department of Vascular Surgery at the Cleveland Clinic, we identified 199 consecutive patients who underwent 206 carotid reoperations (REDOCEAs) for recurrent stenosis from January 1989 through December 1999. These reoperations represented 6% of the 3360 carotid endarterectomies Carotid endarterectomy has been demonstrated to be an effective and durable treatment for both symptomatic and asymptomatic internal carotid stenosis. 1,2 Nevertheless, largely because of patient and physician awareness, the aging population, and the wide availability of reliable noninvasive carotid testing, some patients are identified who require carotid reoperation for recurrent carotid stenosis after prior carotid endarterectomy. Carotid reoperations are often considered to be more technically demanding than primary carotid endarterectomy, 3,4 and some authors have reported higher morbidity rates for reoperations than for primary carotid endarterectomy. 5,6 Consequently, controversy currently exists about the 5 From the Departments of Vascular Surgery a and Biostatistics and Epidemiology, b Cleveland Clinic Foundation. Competition of interest: nil.

Journal of Vascular Surgery, May 1, 1992

thoracoabdominal aneurysms, with an overall 30-day mortality rate of 35%. In 75 operations (58°,6... more thoracoabdominal aneurysms, with an overall 30-day mortality rate of 35%. In 75 operations (58°,6) performed electively, 11 deaths (15%) occurred, and in 54 cases (42%) of either symptomatic or ruptured aneurysms 34 deaths (63%; p < 0.001) occurred. No one survived among six patients with preoperative hypotension (< 90 mm Hg) or cardiac arrest. In 16 patients (12%) the etiology of aneurysms was a result of chronic aortic dissection, and the mortality rate in this subgroup was 44%. In the remaining 113 patients (88%) where the etiology was atherosclerosis, 38 deaths occurred (34%; p = 0.433). Spinal cord ischemia occurred in 25 cases (21%) among 116 patients who survived operation. Partial ischemia occurred in six cases (25%), and complete paraplegia occurred in the remainder. Complete and partial paraplegia occurred in 16 of 42 cases (38%) when all of the thoracic aorta was replaced (Crawford groups I, II) and in 9 of 74 cases (12%) when only the abdominal or lower thoracic aorta was replaced (Crawford groups III, IV; p = 0.016). Other complications included myocardial infarction (14 cases, 11%), respiratory failure (46 cases, 36%), and renal failure (33 cases, 27%). The major prospect for improved early survival of patients with thoracoabdominal aneurysms seems to be early detection and elective repair before the occurrence of symptoms. (J VASC SURG 1992;15:780-8.) The treatment of thoracoabdominal aortic aneurysms (TAAAs) remains one of the most serious challenges in vascular surgery. If TAAAs are untreated, life expectancy is short, with few patients surviving more than 2 years. 1,z Surgical repair is still associated with significant morbidity and mortality, although thanks to the remarkable contributions of Dr. E. Stanley Crawford and others, perioperative complication rates appear to have declined considerably over the past decade. Herein we report the 25-year experience, which spans the modern era of vascular surgery, of the Cleveland Clinic Foundation with TAAA repair, and we review the techniques currently being used to treat this difficult problem.

Journal of Vascular Surgery, Jul 1, 1997

Several randomized trials now have established guidelines regarding patient selection for carotid... more Several randomized trials now have established guidelines regarding patient selection for carotid endarterectomy (CEA) that have been widely accepted but have little relevance unless they are considered in the context of perioperative risk. The purpose of this study was to demonstrate the feasibility of early outcome assessment using a computerized database. Since 1989 demographic information and in-hospital results for all surgical procedures performed by the members of our department have been entered into a prospective registry. For the purpose of this report, we have analyzed the stroke and mortality rates for 2228 consecutive CEAs (2046 patients), including 1924 that were performed as isolated operations and 304 that were combined with simultaneous coronary artery bypass grafting (CABG). This series incidentally contains a total of 153 reoperations for recurrent carotid stenosis. The respective stroke and mortality rates were 0.5% and 1.8% for all isolated CEAs, 4.3% and 5.3% for all CEA-CABG procedures, and 4.6% and 2.0% for carotid reoperations. According to a multivariable statistical model, the composite stroke and mortality rate for isolated CEA was significantly influenced by female gender (p = 0.050), by the urgency of intervention (p = 0.026), and by carotid reoperations (p = 0.024). Gender (p = 0.030) and urgency (p = 0.040) also were associated with differences in the stroke rate alone; furthermore, the incidence of perioperative stroke was higher in conjunction with synthetic patching (odds ratio, 2.6; 95% confidence interval, 1.2 to 5.3) and was marginally higher with primary arteriotomy closure (odds ratio, 2.7; 95% confidence interval, 0.8 to 9.5) compared with vein patch angioplasty (1.3%). The method used to repair the arteriotomy was the only independent factor that qualified for the multivariable composite stroke and mortality models that were applied to the combined CEA-CABG procedures, but too few patients in this cohort had synthetic patches or primary closure to validate the perceived superiority of vein patching. Prospective outcome assessment is essential to reconcile the indications for CEA with its actual results, and it may lead incidentally to important observations concerning patient care.

Journal of Vascular Surgery, May 1, 1985

We reviewed the results, systemic effects, and complications associated with the selective infusi... more We reviewed the results, systemic effects, and complications associated with the selective infusion of low-dose streptokinase in 151 patients. Successful thrombus lysis was achieved in 78% of atherosclerotic thrombotic occlusions less than 30 days old, in 81% of postprocedural occlusions less than 14 days old, and in 87% of patients with thrombosed arteriovenous fistulas no more than 4 days old. During the first 12 hours of treatment 81% to 84% of patients had > 50% decrease in plasma fibrinogen levels and 100% showed the same decline after 24 hours of treatment. The thrombin time was prolonged to at least 1% times the control thrombin time in 33% to 42% of patients measured at 4 hours of therapy and in 93% to 97% of patients measured at 24 hours of treatment. Fifteen patients (9.9%) had major complications. Eleven of these had hemorrhagic complications, two had significant distal emboli, one had a thrombosed brachial artery, and one had a false aneurysm at the catheter entry site. We have found that selective low-dose streptokinase is effective in the treatment of acute and chronic thrombotic occlusions and is a useful adjuvant to vascular reconstruction or percutaneous transluminal angioplasty. Although the local infusion dose is substantially lower than the usual systemic dose, a systemic lytic effect was seen in all patients. Hemorrhagic complications occurred despite customary precautions.

Journal of Vascular Surgery, Sep 1, 1985

In the presence of ipsilateral internal carotid artery (ICA) occlusion, external carotid artery (... more In the presence of ipsilateral internal carotid artery (ICA) occlusion, external carotid artery (ECA) revascularization can improve cerebral perfusion or eliminate an embolic source. From 1974 through 1984, 37 patients at The Cleveland Clinic underwent 42 ECA reconstructions; autologous patch angioplasty and intraluminal shunting were used when feasible. Thirty procedures were limited to primary ECA revascularization, whereas 12 extended procedures were performed as reoperations after previous ECA endarterectomy or required complementary subclavian or intracranial bypass. There were no early postoperative deaths nor neurologic morbidity in the limited group, but one death, four ipsilateral hemispheric strokes, and one retinal embolism occurred in the extended group. Ten patients have died during a follow-up interval of I to 72 months (mean 27 months). Five late deaths were caused by myocardial infarction, only one of which was complicated by a contralateral stroke. Two additional strokes have occurred; one involved the ipsilateral and one the contralateral cerebral hemisphere. Five other patients experienced recurrent cerebral or ocular ischemic symptoms. In conclusion, extended ECA reconstruction is associated with a higher operative risk than limited revascularization. Late follow-up is necessary to detect those patients who may eventually require additional management of recurrent cerebrovascular symptoms or incidental coronary artery disease. (J VAsc SUP-G 1985; 2:709-14.

Journal of Vascular Surgery, Mar 1, 1985

Ligation of atherosclerotic extracranial carotid aneurysms was described nearly 200 years ago, bu... more Ligation of atherosclerotic extracranial carotid aneurysms was described nearly 200 years ago, but resection and direct reconstruction of these unusual lesions currently are assodated with less risk for perioperative neurologic complications as well as with durable late results. During an interval in which carotid endarterectomy was performed in over 1500 patients at The Cleveland Clinic, only six patients underwent surgical management of cervial carotid aneurysms. Aneurysm resection was performed in conjunction with reanastomosis of the internal carotid artery in two patients but required saphenous vein interposition grafts in four others. A temporary carotid shunt was employed routinely and was threaded through the harvested vein before its insertion whenever graft replacement was necessary. Although one vein graft required revision because of early thrombosis, no operative deaths or permanent strokes occurred in this small series. Each patient has remained asymptomatic throughout a maximum follow-up period of 6 years postoperatively. (