Diagnosis and treatment of chronic arterial insufficiency of the lower extremities: a critical review.
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Arteries↗
Biomedical subjects
L M Taylor
Publications and source records attributed to L M Taylor.
Peroneal bypass is equivalent to inframalleolar bypass for ischemic pedal gangrene.
OBJECTIVE: To determine if peroneal bypass is a suitable alternative to inframalleolar bypass in patients with ischemic pedal gangrene. DESIGN: Review of a prospectively acquired vascular registry. SETTING: University practice limited to vascular surgery. PATIENTS: Patients with chronic lower-extremity ischemia and pedal gangrene evaluated between 1985 and 1995 in whom the only options for arterial reconstruction were bypass to the peroneal or an inframalleolar artery. INTERVENTIONS: Peroneal or inframalleolar reverse vein bypass. MAIN OUTCOME MEASURES: Time to healing and lifetable analyses of survival, primary patency, and limb salvage. RESULTS: Eighty-three peroneal and 46 pedal bypasses were performed for ischemic foot gangrene. The groups were equivalent for sex, diabetes mellitus, heart disease, hypertension, renal failure, hypercoagulable states, previous ipsilateral bypass, smoking, and preoperative ankle-brachial indices. Patients with inframalleolar bypass were younger than patients with peroneal bypass (63.9 vs 71.6 years, P = .005) and had higher postoperative ankle-brachial indices (1.02 vs 0.91, P = .004). However, 3-year survival rates (69.1% inframalleolar vs 60.0% peroneal, P = .35), limb salvage rates at 2 years (70.3% vs 85.8%, P = .10), and time to wound healing (19.7 vs 21.6 weeks, P = .66) were equivalent. CONCLUSION: Peroneal and inframalleolar bypass for ischemic pedal gangrene have equivalent intermediate-term survival, limb salvage, and wound healing. Surgeons should not feel obliged to perform inframalleolar bypass for pedal gangrene if peroneal bypass is possible.
Aged↗
Technique of reversed vein bypass for lower extremity ischemia.
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Anastomosis, Surgical↗
Upper extremity thromboembolism after axillary-axillary bypass grafting.
Two patients experienced upper extremity thromboembolism after axillary-axillary bypass grafting (AxAG) for symptomatic subclavian artery stenosis. The first patient, a 67-year-old male, presented with left upper extremity thromboembolism 3 years after AxAG with 8 mm externally support PTFE. An arteriogram revealed a patent AxAG, thrombus in the proximal left subclavian arterial stump just distal to its occlusion, and multiple digital artery emboli. The patient was treated with warfarin for 8 months, with resolution of symptoms. The second patient, a 57-year-old male, occluded his AxAG (8 mm knitted Dacron) with minimal return of symptoms. Non-operative treatment was elected and 4 years later the patient presented with right upper extremity (donor side) thromboembolism. Arteriography revealed occlusion of the AxAG, radial artery, and digital arteries of the index, long and ring fingers. Thrombolytic therapy of the right arm was undertaken with minimal improvement. Subsequent detachment of the AxAG and placement of an interposition reversed saphenous vein graft was performed. Both patients continue to be asymptomatic during follow-up of 4.7 and 2.0 years, respectively.
Aged↗
Long-term outcome of Raynaud's syndrome in a prospectively analyzed patient cohort.
PURPOSE: Knowledge of the long-term clinical outcome of Raynaud's syndrome (RS), essential both for patient counselling and formulation of optimal therapeutic recommendations, is conspicuously deficient in current medical literature. We have prospectively monitored 1039 patients with RS, 118 (11.4%) for more than 10 years to determine whether initial characterization was able to predict outcome. METHODS: At initial presentation, patients were divided into four groups on the basis of vascular laboratory and serologic testing results: vasospastic, serologically positive (spast,sero+) and negative (spast,sero-) and obstructive, serologically positive (obst,sero+) and negative (obst,sero-). RESULTS: Connective tissue disease (CTD) was present initially in 48.6% of patients with spast,sero+ results and 72.9% of patients with obst,sero+ results. Of the remaining patients in these groups, progression to CTD during follow-up occurred in 16.4% of patients with spast,sero+ results and 30.4% of patients with obst,sero+ results. In the > 10-year follow-up group, progression to CTD occurred in 81.8% of patients in the obst,sero+ group. Progression to CTD occurred in 2.0% of patients in the spast,sero-group and 8.5% of patients in the obst,sero- group. Digital ulcers occurred in 15.5% of patients in the spast,sero+ group, 5.2% of patients in the spast,sero- group, 55.6% of patients in the obst,sero+ group, and 48.2% of patients in the obst,sero- group. Digital or phalangeal amputations were required in 1.4%, 1.6%, 11.6%, and 19.0% of these patients, respectively. CONCLUSIONS: The long-term outcome of patients with RS can be predicted by initial serologic studies and separation into vasospastic and obstructive categories. Initial serologic positivity strongly predicts the development of CTD. Initial vascular laboratory classification of obstructive RS strongly predicts digital ulcerations, which occurred in half of these patients regardless of initial serologic study results. Amputations were required in 10% to 20% of patients with obstructive RS. These occurrences did not increase with increased duration of disease. Ulcerations and amputations were rare in patients initially with vasospastic RS.
Adult↗
Prospective comparison of infrainguinal bypass grafting in patients with and without antiphospholipid antibodies.
PURPOSE: The antiphospholipid antibodies (APL)-anticardiolipin antibodies (ACL) and lupus anticoagulant (LA)-are widely believed to be associated with decreased lower extremity bypass graft patency rates. To date, no prospective cohort study has confirmed this assumption. A prospective comparison of the result of infrainguinal revascularization procedures performed since 1990 in patients with and without APL forms the basis of this report. METHODS: Patients who underwent elective infrainguinal bypass procedures from 1990 to 1994 were evaluated for hypercoagulable states (ACL, LA, protein C, protein S, and antithrombin III). Patient data were prospectively entered in a computerized vascular registry, and postoperative follow-up was maintained for life. Graft patency, limb salvage, and patient survival rates were calculated by life-table methods. RESULTS: Three hundred twenty-seven lower extremity bypass grafting procedures were performed in 262 patients. APLs were present in 83 patients (32%); 70 patients (84%) had ACLs only, 11 patients (13%) had LA only, and two patients (3%) had both ACLs and LA. There was no significant difference between APL-positive and APL-negative patients with respect to demographics, associated medical conditions, indication for operations, and type of procedures performed. More patients who had APLs had warfarin treatment after surgery (43% vs 24%, p = 0.002). Life table 4-year primary patency rates showed minimal difference (APL-positive, 43%; APL-negative, 59%; p = 0.087), and no significant difference was noted in assisted primary patency rates (APL positive, 72%; APL negative, 73%; p = NS), limb salvage rates (APL positive, 79%; APL negative, 88%; p = NS), and patient survival rates (APL positive, 67%; APL negative, 66%; p = NS). CONCLUSIONS: APLs were found in a surprising one third of the patients who underwent leg bypass grafting procedures. The majority of APLs identified were ACLs (87%). There was minimal difference in graft primary patency rates, and no difference in assisted primary patency, limb salvage, and survival rates between patients with and without APLs who underwent leg bypass grafting procedures. The extreme morbidity rate associated with APLs in previous reports is not confirmed by this prospective study. APLs should not be regarded as a contraindication to indicated leg bypass grafting procedures.
Aged↗
Improving selection of patients with less than 60% asymptomatic internal carotid artery stenosis for follow-up carotid artery duplex scanning.
PURPOSE: The Asymptomatic Carotid Atherosclerosis Study (ACAS) indicated significant benefit from endarterectomy compared with medical therapy for patients with 60% to 99% asymptomatic internal carotid artery (ICA) stenoses. To date, optimal selection of patients for vascular laboratory follow-up to determine progression from < 60% to > or = 60% asymptomatic ICA stenosis is unknown. To determine which patients with < 60% asymptomatic ICA stenoses are at greatest risk for short-term progression to > or = 60% without symptoms, we reviewed vascular laboratory results and clinical risk factors of consecutive patients who were prospectively observed in a study of atherosclerosis progression. METHODS: Carotid duplex studies were obtained every 6 months and were reviewed for progression from < 60% to > or = 60% asymptomatic ICA stenosis by using criteria that were developed and reported by our laboratory. Clinical risk factors and velocities from initial duplex scans were analyzed for association with progression from < 60% to > or = 60% ICA stenoses without symptoms. RESULTS: Two hundred sixty-three patients (mean age, 66 years) with 434 asymptomatic < 60% ICA stenoses were prospectively observed for a mean of 20 months, with a mean of four examinations per patient. Seventeen patients (6.5%) and 18 ICAs (4%) progressed without symptoms to > or = 60% ICA stenoses at a mean of 18 months. Clinical risk factors associated with progression to > or = 60% asymptomatic ICA stenosis included elevated systolic blood pressure and decreased ankle-brachial index (p = 0.05). The mean initial ICA peak systolic velocity (PSV) in ICAs that progressed to > or = 60% asymptomatic stenoses was 180 cm/sec, compared with 104 cm/sec in asymptomatic ICAs that did not progress to > or = 60% (p = 0.0003). Thirty-one percent of asymptomatic ICAs that had initial PSVs of 175 cm/sec or greater progressed to > or = 60% stenosis, whereas only 1.8% that had initial PSVs less than 175 cm/sec progressed to > or = 60% asymptomatic stenoses (p < 0.001). The life-table-determined rate of freedom from progression to > or = 60% stenosis was 94% at 4 years for asymptomatic ICA lesions that had initial PSVs less than 175 cm/sec, compared with 14% at 3 years for lesions that had initial PSVs > or = 175 cm/sec. CONCLUSIONS: Early progression from < 60% asymptomatic ICA stenoses to > or = 60% asymptomatic ICA stenoses occurs infrequently. Patients who are at the greatest risk of early progression without symptoms to an ACAS-positive lesion can be identified from the ICA PSV at their initial duplex examination. Early vascular laboratory follow-up of asymptomatic ICA stenoses may be limited to a relatively small group.
Aged↗
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 surgeon's 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.
Adult↗
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.
Aged↗
Reducing perioperative myocardial infarction following vascular surgery. The potential role of beta-blockade.
OBJECTIVE: To determine which perioperative variables may influence the occurrence of perioperative myocardial infarction (PMI) following vascular surgery. DESIGN: Case-control study. SETTING: Combined Veterans Affairs Medical Center-university hospital vascular service. PATIENTS: During a 4-year period, all major vascular surgical operations (N = 2088) were evaluated with serial postoperative electrocardiography and cardiac enzyme measurements. Patients with PMI following nonemergent vascular surgery (N = 53) were matched with randomly selected control patients without PMI (N = 106) for age, gender, type of operation, hypertension, and symptoms of coronary artery disease. MAIN OUTCOME MEASURES: The two groups were compared for operative blood loss, blood pressure, and heart rate as well as length of operation, type of anesthetic, and use of perioperative beta-blockers, nitroglycerine, calcium channel blockers, vasopressors, and angiotensin-converting enzyme inhibitors. RESULTS: beta-Blockers were used less frequently in patients with PMI than in control patients without PMI (30% vs 50%; P = .01). Overall beta-blockade was associated with a 50% reduction in PMI (P = .03). Perioperative myocardial infarction was not associated with length of operation, type of anesthetic, blood pressure, or use of other medications. CONCLUSIONS: beta-Blockade is associated with a decreased incidence of PMI in patients undergoing vascular surgery. Prophylactic perioperative use of beta-blockers may decrease PMI in patients requiring major vascular surgery. A prospective randomized trial of beta-blockers in these patients appears to be warranted.
Adrenergic beta-Antagonists↗
Prevalence of asymptomatic carotid stenosis in patients undergoing infrainguinal bypass surgery.
BACKGROUND: The prevalence of asymptomatic carotid stenosis in patients with lower-extremity ischemia is unknown. This report represents the largest carotid screening program to date of patients undergoing leg bypass. DESIGN: Patients undergoing infrainguinal bypass from 1987 through 1993 on the vascular surgery service at Oregon Health Sciences University, Portland, underwent routine carotid duplex examinations to detect the presence of asymptomatic carotid stenosis. PATIENTS: During the study period, 352 patients underwent infrainguinal revascularization for ischemia, of whom 225 (64%) had no prior carotid surgery, carotid arteriography, or cerebrovascular symptoms. There were 117 men and 108 women, with a mean age of 67 years. The indication for surgery was limb salvage in 67% and claudication in 33% of patients. RESULTS: Sixty-four patients (28.4%) who required lower-extremity revascularization had hemodynamically significant asymptomatic carotid artery stenosis or occlusion; 12.4% had stenosis of 60% or greater, the qualifying level for randomization in the Asymptomatic Carotid Atherosclerosis Study. Based on these findings, eight patients with carotid stenosis of 80% or greater underwent elective carotid endarterectomy. There were no postoperative neurologic events in the 225 leg bypass patients. By multivariate logistic regression analysis, the presence of carotid bruit (P < .001) and the presence of rest pain (P = .006) were associated with carotid stenosis of 50% or greater. Limiting screening to patients with carotid bruit, limb salvage indications for surgery, and/or advanced age excluded significant numbers of patients with stenosis; thus, these were not effective screening strategies. CONCLUSION: Screening carotid duplex scanning is indicated in patients who require lower-extremity revascularization.
Aged↗
Usefulness of fasting and postprandial duplex ultrasound examinations for predicting high-grade superior mesenteric artery stenosis.
PURPOSE: A fasting duplex ultrasound examination of the superior mesenteric artery (SMA) accurately detects high-grade (> 70%) stenosis. It has been postulated that postprandial mesenteric duplex scanning may further stratify stenosis and improve the ability of a fasting examination to detect a high-grade stenosis. We performed fasting and postprandial duplex scanning of 25 healthy controls and 80 patients with vascular disease undergoing aortography to determine whether postprandial mesenteric duplex scanning provides information beyond a fasting study alone. METHODS: Patients with vascular disease were divided into three groups based on lateral aortography results: group 1, 0% to < 30% SMA stenosis (n = 61); group 2, 30% to < 70% stenosis (n = 10); and group 3, 70% to 99% stenosis (n = 9). Fasting mesenteric duplex scanning was defined as positive for 70% to 99% stenosis if the peak systolic velocity (PSV) was > or = 275 cm/s. The ability of either fasting or postprandial mesenteric duplex scanning, and their combination, to predict high-grade (70% to 99%) SMA stenosis was determined using angiographic control. RESULTS: Mean fasting SMA PSV did not differ among controls and groups 1 and 2. Postprandial PSV increased significantly in all groups, but was not different among controls and groups 1 and 2. Mean fasting PSV was significantly higher, and the postprandial increase in PSV significantly lower, in group 3 compared with controls and with groups 1 and 2. Fasting mesenteric duplex scanning predicted 70% to 99% SMA stenosis, with 89% sensitivity, 97% specificity, 80% positive predictive value, 99% negative predictive value, and 96% accuracy. Corresponding values for postprandial scanning were 67%, 94%, 60%, 96%, 91%, and for the combination of normal fasting and postprandial scanning 67%, 100%, 100%, 96%, 96%, respectively. CONCLUSION: Postprandial increases in SMA PSVs are blunted in patients with high-grade stenosis, but feeding velocities do not stratify between lesser degrees of stenosis. Both fasting and postprandial PSVs identify high-grade (> 70%) stenosis. Their combination marginally improves fasting duplex scan specificity and positive predictive value. Postprandial scanning is not necessary for the diagnosis of high-grade stenosis if a fasting study identifies a PSV > or = 275 cm/s. The combination of normal fasting and postprandial mesenteric duplex ultrasound scanning may effectively rule out high-grade SMA stenosis.
Adolescent↗
Upper extremity thromboembolism caused by occlusion of axillofemoral grafts.
BACKGROUND: The axillofemoral bypass graft (AxFG) is increasingly accepted as treatment for lower extremity ischemia caused by aortoiliac occlusive disease in high-risk patients. The incidence of upper extremity (UE) thromboembolism caused by occlusion of an AxFG and the results of treatment form the basis for this report. METHODS: From 1984 to the present, all patients undergoing axillofemoral bypass grafting were followed up in a vascular registry. A standardized operative technique, using an externally supported 8-mm polytetrafluoroethylene graft, was used in performing 202 AxFGs in 182 patients. UE thromboembolism caused by occlusion of an AxFG was identified by retrospective patient record review. RESULTS: Occlusion of an AxFG occurred in 20 patients. Fifteen patients (75%) underwent immediate revision of the occluded graft. Two patients (10%) developed UE thromboembolism simultaneous with graft occlusion. One of these patients had immediate revision of the graft, and 1 had brachial embolectomy only. This patient and 4 others (25%) had the occluded AxFG left in place. Four of these 5 patients (80%) developed UE thromboembolism at 26 days, 2 years, 5 years, and 7 years, respectively, after occlusion. Overall, six UE thromboembolic complications occurred in 5 patients. CONCLUSIONS: UE thromboembolism represents a significant and specific complication of occluded AxFGs in our series (2.7% of patients, 25% of occluded grafts). It may be prudent to prophylactically detach the axillary portion of the graft and repair the axillary artery in patients who do not require immediate revision of an occluded AxFG.
Algorithms↗
Diagnosis and long-term clinical outcome in patients diagnosed with hand ischemia.
PURPOSE: The long-term clinical outcome of patients diagnosed with digital artery obstruction and symptomatic hand ischemia is largely unknown. Our long-term experience with the diagnosis of symptomatic digital artery obstruction and the long-term natural history of this condition forms the basis for this report. METHODS: From 1971 to 1985, 44 patients with symptomatic hand ischemia and palmar or digital arterial obstruction underwent arteriography and digital photoplethysmography (PPG). Patients were grouped according to severity of hand ischemia symptoms, including ulceration and digital amputation and the presence of a connective tissue disease (CTD). Arteriography was compared with PPG by creating an objective severity scale (digital obstruction index [DOI]). RESULTS: Average follow-up was 15.2 years (range 10 to 22 years). Initially 21 patients (48%) had moderate symptoms, and 23 patients (52%) had severe symptoms of hand ischemia. Follow-up symptoms in 28 patients improved (13 of 26 with CTD, 15 of 18 without CTD), in 15 patients (12 of 26 with CTD, 3 of 18 without CTD) remained unchanged, and in only 1 patient (1 of 26 with CTD) worsened. Seventeen (65%) patients with CTD (n = 26) had development of one or more ulcers, and six (24%) underwent one or more digital amputations. Four (22%) patients without CTD (n = 18) had finger ulceration (p < 0.012 compared with patients with CTD), and one patient (6%) underwent subsequent digital amputation (p = NS). The arteriography-DOI and PPG-DOI were equally accurate in determining severity of finger ischemia as manifested by severity of symptoms or ulcer development. CONCLUSIONS: The favorable long-term prognosis of symptomatic finger artery occlusion described herein mandates the avoidance of premature finger amputation. Patients with CTD fare worse, but even in this group tissue loss is modest. Finger PPG is as accurate as arteriography for determining severity of hand ischemia.
Adolescent↗
Progression of atherosclerosis in arteries distal to lower extremity revascularizations.
PURPOSE: The characteristics of progression of atherosclerotic occlusive disease (AOD) of the lower extremities after revascularization are unknown. Duplex scanning or angiography were used to determine progression in 150 patients after they underwent revascularization for AOD. METHODS: Follow-up studies were compared with presurgical arteriograms. Superficial femoral (SFA) and popliteal arteries were graded as less than 50% stenosis, 50% to 99% stenosis, or occluded. Tibial arteries were graded with regard to whether they were continuously patent from the popliteal trifurcation to the ankle. Progression was defined as an increase in one stenosis category. RESULTS: At a mean follow-up of 4.8 years, 18% of native arteries, 39% of extremities, and 52% of patients demonstrated progression of AOD. Overall, 21% of arteries in patients undergoing infrainguinal bypass and 14% of arteries in patients undergoing suprainguinal bypass demonstrated progression (p = 0.004). Progression was more frequently detected in examinations performed more than 4 years after baseline arteriography (66%) than in examinations performed 6 months to 2 years (45%, p = 0.032) or 2 to 4 years (44%, p = 0.029) after baseline arteriography. Thirty percent of SFAs demonstrated progression, and 32% with 50% stenosis or greater at baseline became occluded. There was no difference in SFA, popliteal, or tibial artery progression in revascularized versus nonrevascularized extremities after suprainguinal bypass. There was no difference in tibial artery progression in operated and nonoperated limbs after femoropopliteal artery bypass. CONCLUSIONS: AOD progression occurs frequently in patients requiring revascularization and is more prevalent in patients requiring femoropopliteal than in patients requiring suprainguinal bypass. AOD progression in patients undergoing vascular surgery is associated with the pattern of disease producing lower extremity ischemia and does not appear to be worsened by arterial reconstruction.
Adult↗
Do normal early color-flow duplex surveillance examination results of infrainguinal vein grafts preclude the need for late graft revision?
PURPOSE: Optimal duration of postoperative duplex surveillance of infrainguinal vein grafts is not known. Previous reports have suggested nearly all vein graft stenoses are present within the first postoperative year, and normal duplex examination results during this time eliminate the need for ongoing graft surveillance. To determine whether surveillance may be safely discontinued in patients with normal early postoperative surveillance studies, we reviewed the color-flow surveillance examinations in our patients who underwent infrainguinal reverse vein graft revisions during a 4 1/2 year period. METHODS: Clinical and vascular laboratory records were reviewed of all patients who underwent infrainguinal reverse vein bypass grafting followed by subsequent graft revision for a duplex scanning-detected abnormality at our institution between January 1990 and July 1994. RESULTS: Of 447 infrainguinal reverse vein bypasses performed, 36 (8.1%) underwent surgical revision as a result of an abnormal finding during routine duplex surveillance. The initial postoperative duplex examination was obtained within 2 weeks of graft implantation in 23 (64%) patients, between 2 weeks and 3 months in 10 (28%) patients, and between 3 and 6 months in three (8%) patients. Duplex abnormalities prompting revision included 11 (31%) grafts with a mid-graft peak systolic velocity (PSV) < or = 45 cm/sec, 23 (64%) grafts with a focal PSV > or = 200 cm/sec, one graft with a PSV > or = 150 cm/sec but < 200 cm/sec, and one thought to be occluded by duplex but found to be patent by angiography. Abnormal duplex findings were initially detected within 2 weeks of graft implantation in five (14%) patients, between 2 weeks and 3 months in eight (22%) patients, from 3 to 6 months in 12 (33%) patients, from 6 to 12 months in six (17%) patients, and > 1 year in five (14%) patients. In only 25% of cases were mid-graft PSVs < or = 45 cm/sec or focal velocities > or = 200 cm/sec identified on the initial examination; 75% were found during subsequent surveillance. CONCLUSIONS: Although most reverse vein graft abnormalities detected by duplex surveillance and prompting graft revision appear within the first postoperative year, many are not detected on the initial examination. In our recent experience 31% of duplex abnormalities leading to vein graft revision were first detected more than 6 months after operation. Discontinuation of graft surveillance based on normal early findings will result in thrombosis of some vein grafts that may otherwise be salvaged.
Adult↗
Deep vein thrombosis associated with lower extremity amputation.
PURPOSE: Patients undergoing lower extremity amputation are perceived to be at high risk for deep vein thrombosis (DVT). Limited data are available, however, to confirm this impression. The purpose of this study is to prospectively document the incidence of DVT complicating lower extremity amputation. METHODS: During a recent 28-month period, 72 patients (71 men, 1 woman; mean age 68 years) undergoing major lower extremity amputation (31 above-knee and 41 below-knee) were prospectively evaluated with perioperative duplex scanning for DVT. RESULTS: DVT was documented in nine (12.5%) patients (one bilateral, four ipsilateral, and four contralateral to amputation). Patients with a history of venous disease were at significantly higher risk for development of DVT (p = 0.02). Thrombi were located at or proximal to the popliteal vein in eight patients and were isolated to the tibial veins in one patient. DVT was identified before operation in six patients and after operation in three. Patients with DVT were treated with heparin anticoagulation, with no patient experiencing clinical symptoms compatible with pulmonary embolism. CONCLUSIONS: In our recent experience, lower extremity amputation is associated with DVT at or proximal to the popliteal vein in 11% of patients. Documentation of DVT prevalence is essential to assist surgeons in planning a management strategy for prevention, diagnosis, and treatment of DVT associated with lower extremity amputation.
Aged↗
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.
Blood Flow Velocity↗