James M. Edwards

Present status of reversed vein bypass grafting: Five-year results of a modern series

From January 1980 through December 1988, 564 limbs in 434 patients were treated for infrainguinal arterial ischemia. Of these, 516 limbs in 387 patients underwent reversed vein bypass grafting. The remainder were treated by primary amputation (11 limbs, 1.9%) or by prosthetic bypass (37 limbs, 6.4%). The indications for operation were limb salvage in 80% of limbs and claudication in 20%. Adequate ipsilateral greater saphenous vein was available for 285 (55%) grafts, with reversed vein bypass achieved in the other 231 operations by use of distal graft origins (151 grafts), use of alternate vein sources (120 grafts), and splicing of venous segments (81 grafts). Seventy-six grafts (15%) were to the above-knee popliteal artery, 199 grafts (37%) were to the below-knee popliteal artery, and 241 grafts (47%) were to infrapopliteal arteries, 26 of which (11%) were to inframalleolar arteries. The primary and secondary patencies for all grafts at 5 years were 75% and 81%, respectively. Grafts to infrapopliteal arteries had significantly worse primary patency (69%) at 5 years than did grafts to the popliteal artery (77%, above knee; 80%, below knee) and grafts formed of adequate ipsilateral greater saphenous vein had significantly better primary patency (80%) than did grafts performed when this conduit was not available (68%). Secondary patency of all graft categories ranged from 76% to 85%, and there were no significant differences regardless of site of distal anastomosis, source of venous conduit, or site of graft origins. We prefer the use of reversed vein bypass grafting for lower extremity revascularization both because of the excellent patency results and because the technique can be applied to the larger number of patients in our practice who lack intact ipsilateral greater saphenous vein, in contrast to in situ vein bypass procedures.

Screening for asymptomatic internal carotid artery stenosis: Duplex criteria for discriminating 60% to 99% stenosis

PURPOSE The Asymptomatic Carotid Atherosclerosis Study (ACAS) showed that carotid endarterectomy reduces stroke risk in symptom-free patients with 60% or greater internal carotid artery (ICA) stenosis. This will surely lead to the performance of an increased number of screening duplex examinations. Assuming that positive study results will lead to arteriography or endarterectomy and keeping in mind the modest benefit for prophylactic endarterectomy demonstrated by ACAS (absolute risk reduction for ipsilateral stroke of 5.8% at 5 years), duplex criteria for 60% or greater ICA stenosis must have high positive predictive values (PPV). Determining criteria for 60% or greater stenosis, which emphasized high accuracy and PPV, forms the basis for this study. METHODS Stenoses detected by angiography in 352 ICAs were blindly compared with those detected by duplex scanning. Duplex criteria were determined for highest overall accuracy in detection of 60% or greater ICA stenosis and for 95% or greater PPV. RESULTS Maximal accuracy for detection of 60% or greater stenosis was 90%. This was achieved by the combination of a peak systolic velocity of 260 cm/sec or greater and an end diastolic velocity of 70 cm/sec or greater (sensitivity 84%, specificity 94%, PPV 92%). The 95% PPV for 60% or greater stenosis results from combining peak systolic velocity of 290 cm/sec or greater and end diastolic velocity of 80 cm/sec or greater. CONCLUSIONS With use of these criteria duplex scanning accurately detects with high PPVs the threshold level of ICA stenosis defined in ACAS as receiving stroke reduction benefit from prophylactic carotid endarterectomy. These criteria should be useful for carotid artery screening and minimizing unneeded intervention.

Long-term hemodynamic and clinical sequelae of lower extremity deep vein thrombosis

Forty-seven patients with phlebographically confirmed lower extremity deep vein thrombosis (DVT) were reexamined 5 to 10 years (mean, 7 years) after the thrombotic event. Clinical symptoms were recorded and the following noninvasive venous vascular laboratory tests were performed: Doppler examination to determine venous valve competence and photoplethysmography to measure ambulatory venous pressure and venous recovery time. Twenty-eight control subjects underwent similar examination. Although only 10 of 47 patients (21%) were asymptomatic, venous ulceration had developed in only two patients. The symptomatic patients had varying degrees of edema, pigmentation, and varicosities. Eighty-three percent of DVT patients had abnormal vascular laboratory findings. Both the severity of clinical symptoms and the magnitude of the hemodynamic abnormalities generally correlated with the extent of the initial thrombus. However, only 47% of patients whose initial thrombus appeared limited to the calf were asymptomatic, and only 25% of this group had normal venous hemodynamic findings. This study indicates that 5 to 10 years after lower extremity DVT 80% of patients will have both symptoms and abnormal venous hemodynamics regardless of the initial site of the thrombosis.

Intraabdominal paraanastomotic aneurysms after aortic bypass grafting

Although the reported incidence of intraabdominal paraanastomotic aneurysms after abdominal aortic bypass grafting ranges from 1% to 15%, the true incidence is unknown because few studies have used routine, serial radiographic or sonographic imaging studies. Since July 1, 1988, we have used yearly abdominal sonography examinations to monitor our patients with aortic grafts. In the first 33 months we studied 138 patients. Medical records of 111 of these were available for review and form the basis of this report. Eleven patients (10%) were found to have intraabdominal paraanastomotic aneurysms ranging in overall size from 4.1 to 6.2 cm (mean, 5.0 +/- 0.7 cm). The mean time between operation and detection of an aneurysm was 144 +/- 101 months (range, 8 to 336 months). Three paraanastomotic aneurysms occurred within 3 years of operation, and the remaining eight occurred late (7 to 28 years). By life-table analysis, the incidence of paraanastomotic aneurysms was 27% at 15 years. Paraanastomotic aneurysms were classified as either pseudoaneurysms (presumed disruption of the anastomotic suture line, n = 7) or as true aneurysms (widening of the adjacent aorta, n = 4). True aneurysms occurred only after repair of an abdominal aortic aneurysm, whereas pseudoaneurysms were more frequent after bypass for occlusive disease. The finding of paraanastomotic aneurysms in 10% of our patients supports the use of yearly sonography for routine follow-up after aortic grafting.

Improved results with conventional management of infrarenal aortic infection

PURPOSE Interest in alternative methods, such as autogenous vein grafts and aortic allografts, for the management of infrarenal aortic infection (IRAI) has been stimulated by the historically disappointing results with conventional surgical management. Recently, there have been dramatic improvements in the results of axillofemoral bypass grafting (AXFB) followed by excision of the IRAI that have gone relatively unrecognized. The purpose of this report is the presentation of modern-day results in the treatment of IRAI with conventional surgical methods. METHODS From January 1, 1983, through June 30, 1998, patients with IRAI underwent treatment with AXFB and complete excision of the IRAI. The patients were followed for survival, limb salvage, and AXFB graft patency. The results were tabulated with life-table methods. RESULTS During the 15-year study period, 60 patients (51 men, nine women; mean age, 68 years) underwent treatment for IRAI (50 graft infections, including 16 graft-enteric fistulae, and 10 primary aortic infections). The mean follow-up period was 41 months. The perioperative mortality rate was 13% (12% for graft infection, and 20% for primary infection). The overall 2-year and 5-year survival rates were 67% and 47%, respectively. The limb salvage rates at 2 and 5 years were 93% and 82%, respectively. The 5-year primary AXFB graft patency rate was 73%. CONCLUSION These results show an improvement with the conventional management of IRAI equal or superior to those results reported with alternative methods, including femoral vein grafts or aortic allografts. These results should be regarded as the modern standard with which alternative therapies can be compared.

Comparison of axillofemoral and aortofemoral bypass for aortoiliac occlusive disease

PURPOSE A comparison of aortofemoral bypass grafting (AOFBG) and axillofemoral bypass grafting (AXFBG) for occlusive disease performed by the same surgeons during a defined interval forms the basis for this report. METHODS Data regarding all patients who underwent AOFBG of AXFBG for lower-extremity ischemia caused by aortoiliac occlusive disease were prospectively entered into a computerized vascular registry. The decision to perform AOFBG rather than AXFBG was based on assessment of surgical risk and the surgeons preference. This report describes results for surgical morbidity, mortality, patency, limb salvage, and patient survival for procedures performed from January 1988 through December 1993. RESULTS We performed 108 AXFBGs and 139 AOFBGs. AXFBG patients were older (mean age, 68 years compared with 58 years for AOFBG, p<0.001), more often had heart disease (84% compared with 38%, p<0.001), more often underwent surgery for limb-salvage indications (80% compared with 42%, p<0.001). No significant differences were found in operative mortality (AXFBG, 3.4%; AOFBG, <1.0%, p=NS), but major postoperative complications occurred more frequently after AOFBG (AXFBG, 9.2%; AOFBG, 19.4%; p<0.05). Follow-up ranged from 1 to 83 months (mean, 27 months). Five-year life-table primary patency, limb salvage, and survival rates were 74%, 89%, and 45% for AXFBG and 80%, 79%, and 72% for AOFBG, respectively. Although the patient survival rate was statistically lower with AXFBG, primary patency and limb salvage rates did not differ when compared with AOFBG. CONCLUSION When reserved for high-risk patients with limited life expectancy, the patency and limb salvage results of AXFBG are equivalent to those of AOFBG.

Results of bypass to the popliteal and tibial arteries with alternative sources of autogenous vein

PURPOSE The goal of an all-autogenous policy for infrainguinal arterial bypass requires that many bypasses be performed with alternative autogenous veins (AAV) because an adequate length of ipsilateral or contralateral greater saphenous vein (GSV) is not available. The durability and efficacy of infrainguinal vein bypasses constructed of venous conduits other than a single segment of greater saphenous vein (SSGSV) is, however, questioned. METHODS AAV and GSV bypasses were reviewed from 1980 through 1994. Patients who required bypass to the popliteal or a tibial artery were compared for vascular surgical history and vascular disease risk factors and life-table survival. AAV and SSGSV procedures were compared for indications for surgery, morbidity and mortality rates, limb salvage rates in patients who underwent surgery for limb-salvage indications, subsequent need for revision, and life-table-assisted primary patency. RESULTS Nine hundred nineteen autogenous vein bypasses were performed to the popliteal or a tibial artery--187 (20%) with AAVs, including whole or partial arm vein conduits in 144 grafts (77%). One hundred fourteen AAVs (61%) required vein splicing. The mortality rate was 2% for SSGSV bypasses and 1% for AAV bypasses. The morbidity rate was higher for GSV surgery as a result of increased wound complications (11% vs 5%; p=0.02). Sixty-seven percent of patients with AAV bypass extremities had undergone previous ipsilateral arterial surgery, compared with 20% of patients with SSGSV bypasses (p0.0005). AAV bypasses were more likely to be to a tibial artery (71% vs 45%; p<0.0001). Twelve percent of SSGSV and 15% of AAV popliteal bypasses required revision (p=NS). The 5-year assisted primary patencies were 82%, 77%, and 63%, with limb salvage rates of 91%, 86%, and 74% for ipsilateral SSGSV, contralateral SSGSV, and AAV femoropopliteal bypasses, respectively. Twelve percent of SSGSV and 30% of AAV tibial bypasses required revision (p=0.0001). The 5-year assisted primary patencies were 74%, 82%, and 72%, with limb salvage rates of 84%, 92% and 78% for ipsilateral SSGSV, contralateral SSGSV, and AAV femorotibial bypasses, respectively. CONCLUSION AAV bypasses can provide overall results comparable with SSGSV bypasses.

The role of duplex scanning in the selection of patients for transluminal angioplasty

As part of our initial evaluation to determine whether patients with lower extremity ischemia are candidates for intervention, arterial duplex examinations are performed in the noninvasive vascular laboratory. Patients with isolated short stenoses on the duplex examination are referred for transluminal angioplasty. One hundred thirty-four arteriograms were performed for ischemic peripheral vascular disease in 122 patients between July 1987 and March 1990. One hundred ten (82%) of the arteriograms were preceded by a lower extremity arterial duplex evaluation. Fifty cases (45%) were scheduled for transluminal angioplasty based on the findings of the duplex examination. Transluminal angioplasty was performed in 47 of 50 cases (94%). No significant differences in age, sex, or diabetes were found between the patients who were referred for transluminal angioplasty and those who were not. These data demonstrate that duplex scanning of the lower extremities allows the detection of lesions that will be amenable to transluminal angioplasty. We think that duplex scanning should become the standard screening tool for detection of treatable lower extremity lesions.

Reversed vein bypass to infrapopliteal arteries: modern results are superior to or equivalent to in-situ bypass for patency and for vein utilization

In recent years many reports have attributed improved patency and improved vein utilization with lower extremity arterial bypass to infrapopliteal arteries to the use of the in-situ vein graft technique (ISVB). This report describes 110 reversed vein bypasses (RVB) to infrapopliteal arteries performed from 1980-1986. Thirty-three per cent of these patients did not have an intact ipsilateral greater saphenous vein. One hundred per cent of patients had autogenous RVB performed using a variety of techniques, including vein splicing, use of arm veins, lesser saphenous veins, branch veins, and use of graft origins distal to the common femoral artery. The life table patency figures for these grafts are 90%, 85%, and 85% at 1 year, 3 years, and 5 years, respectively. The life table limb salvage at 5 years is 93%. These figures for patency, vein utilization, and limb salvage for modern RVB to infrapopliteal arteries are clearly equal to or superior to any reported figures for ISVB. Results for RVB are greatly improved when compared with historic controls, as are results for ISVB. There is no evidence to date demonstrating superiority of one technique versus another.

Autogenous reversed vein bypass for lower extremity ischemia in patients with absent or inadequate greater saphenous vein

This report has presented the results of 329 reversed vein bypasses performed for lower extremity ischemia over a 6 3/4 year period. One hundred eighty-nine bypasses were formed from intact ipsilateral greater saphenous veins of adequate size and length. One hundred forty bypasses were formed in patients in whom the ipsilateral greater saphenous vein was absent or of inadequate size or length to complete the bypass. The grafts in these patients were accomplished using a variety of techniques including distal graft origin, use of arm veins and lesser saphenous veins, and use of vein splicing. The patency rates of these grafts were equivalent to those achieved using adequate intact ipsilateral greater saphenous vein. In view of these results, we conclude that the absence of a greater saphenous vein does not preclude successful autogenous lower extremity vein bypass and that prosthetic bypass is rarely justified.