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T W Wakefield

Publications and source records attributed to T W Wakefield.

At least 19 recordsLinked to original sources
PubMed2003

Decrease in fibrin content of venous thrombi in selectin-deficient mice.

The purpose of this study was to quantify the fibrin content of thrombi produced in a mouse model of venous thrombosis and correlate this to thrombus mass. The role of P-selectin, E-selectin, and IL-10 on thrombus fibrin content was analyzed using knockout (KO) mice. Five groups of mice were evaluated: control (N = 10), P-selectin KO (N = 7), E-selectin KO (N = 5), combined E-/P-selectin KO (N = 12), and IL-10 KO (N = 10). Venous thrombosis was induced by ligation of the infrarenal IVC. Mice were sacrificed on postoperative days (POD) 2 and 6. Thrombus mass was calculated. Sections of IVC were stained with an antibody that cross reacts with mouse fibrin. The distribution of RGB color pixels was generated from digitized micrographs of the thrombus of each animal. The mean pixel value for each group was compiled and analyzed using 2-way ANOVA. Mean pixel value per group was correlated with the mean thrombus mass per group. Color analysis demonstrated significant decreases in the analyzed fibrin content on POD-2 between the control vs E-/P-selectin KO (P < 0.05) and control vs IL-10 KO (P < 0.05) groups. In addition, significantly less fibrin staining was noted on POD-6 between the control vs E-selectin KO (P = 0.03), control vs P-selectin KO (P = 0.01), and control vs E-/P-selectin KO (P < 0.01). There was a strong overall correlation between the mean pixel value for each group and the thrombus mass (R = 0.964; P < 0.01). This study demonstrates a difference in fibrin content of thrombi produced in animals deficient in E-selectin, P-selectin, and IL-10, supporting their importance in thrombus amplification, fibrin formation, and the mass of thrombus formed.

Animals↗
PubMed2002

Triplex ultrasound: elasticity imaging to age deep venous thrombosis.

Deep venous thrombosis (DVT), and its sequela, pulmonary embolism (PE), is the leading cause of preventable in-hospital mortality in the USA and other developed countries. After it is detected, acute clots must be differentiated from chronic DVT for appropriate treatment. However, there are no reliable thrombus staging methods presently available in clinical practice. In this study, we tested the hypothesis that blood clots can be detected and staged using a triplex ultrasound (US) test. Triplex US is based on a "gold standard" duplex US technique augmented by US-based reconstructive elasticity imaging. Fibrin-composed blood clots harden with development and organization. By imaging clot elasticity, it may be possible to both detect and differentiate clots and, therefore, provide an urgently needed noninvasive means of DVT staging.

Animals↗
PubMed2001

Interleukin-8 administration enhances venous thrombosis resolution in a rat model.

BACKGROUND: Therapy for deep vein thrombosis (DVT) resolution in those patients in whom a complication or contraindication to anticoagulation occurs is limited. As prior work suggests that thrombus maturation involves early influx of neutrophils (PMN) and neovascularization, we hypothesized that administering the proinflammatory/proangiogenic chemokine interleukin (IL)-8 might accelerate thrombus resolution. MATERIALS AND METHODS: An established rodent model of DVT (inferior vena cava [IVC] ligation) was used whereby daily intravenous recombinant human IL-8 (1 microg) or vehicle control was administered, with sacrifice at 4 and 8 days. Prior to sacrifice and at harvest, duplex ultrasound of the DVT and femoral venous pressure measurements were performed. Thrombi were analyzed by immunohistochemical techniques for PMN, monocytes, and neovascularization; for chemokines, by enzyme-linked immunoassay; and fibrosis, by hydroxyproline assay and trichrome staining. RESULTS: IL-8 accelerated thrombus dissolution 4 days after IVC ligation, with 6-fold increased thrombus blood flow by duplex ultrasound and a 23% increased absolute femoral venous pressure compared with controls (both P < 0.05). These findings may be partially explained by the fact that animals receiving IL-8, as compared with controls, had 2.5-fold greater thrombus neovascularization (with a trend continuing to 8 days) and increased PMN at 4 days. Thrombus vascular endothelial growth factor was significantly reduced at 8 days postligation, while monocyte chemotactic protein-1 and macrophage inflammatory protein-1alpha were not altered by IL-8 administration. At 8 days post-IVC-ligation, fibrosis was 12-fold greater with IL-8 treatment compared with controls. CONCLUSIONS: A proinflammatory/proangiogenic thrombus milieu, as conferred by IL-8, enhances thrombus resolution and underscores the important relationship between neovascularity and inflammation.

Animals↗
PubMed2001

Gadolinium-enhanced MR angiography (Gd-MRA) of thoracic vasculature in an animal model using double-dose gadolinium and quiet breathing.

OBJECTIVE: To evaluate a gadolinium-enhanced MR angiography (Gd-MRA) imaging protocol for the assessment of thoracic vessels using double-dose gadolinium and quiet breathing. An animal model was used to simulate imaging in infants and young children. MATERIAL AND METHODS: Six baboons (Papio anubis), mean weight 5.7 kg, were sedated and intubated. After the injection of double-dose Gd-DTPA (0.2 mmol/kg) through a peripheral vein, a coronal spoiled 3D gradient-echo volume acquisition was obtained during quiet breathing. Two radiologists reviewed the images for visualization of aortic arch, brachiocephalic vessel origins, pulmonary arteries (central, upper lobe and descending branches), and pulmonary veins (upper and lower). RESULTS: Visualization was excellent for the aortic arch, brachiocephalic vessel origins, and pulmonary arteries, including the hilar branches. Visualization was excellent for the lower and right upper pulmonary veins and fair for the left upper pulmonary vein. There was excellent agreement between radiologists. CONCLUSION: Imaging of thoracic vessels with Gd-MRA using double gadolinium during quiet breathing was effective in our animal model. The advantages of this technique include a short imaging time and depiction of vascular segments--branches of pulmonary arteries and intraparenchymal segments of pulmonary veins--not optimally visualized with other non-invasive imaging techniques.

Animals↗
PubMed2001

Impact of chronic obstructive pulmonary disease on elective and emergency abdominal aortic aneurysm repair.

OBJECTIVE: Chronic obstructive pulmonary disease (COPD) is associated with abdominal aortic aneurysm (AAA) expansion and is considered by some to be a relative contraindication to conventional aortic surgery. This study was undertaken to determine if COPD increases operative death, morbidity, intensive care unit (ICU) length of stay (LOS), and hospital LOS, after AAA repair. METHODS: Data from national administrative records supplemented with laboratory data previously obtained for a system-wide study were analyzed in a retrospective review of 1053 consecutive patients (264 with and 789 without COPD) undergoing operation for intact or ruptured AAAs in Veterans Administration Hospitals from 1997 to 1998. Bivariate comparisons and multivariate regression were used to evaluate the impact of COPD on the number of days of ventilation, ICU LOS, total hospital LOS, and death, while controlling for other known risk factors, including acute myocardial infarction, renal failure, and age. RESULTS: The mortality rate in elective aneurysm patients did not differ (P =.99) between patients with (3.7%) or without COPD (3.7%). However, elective AAA repair was associated with longer hospital LOS (14.4 vs 12.3 days, P =.01), longer ICU LOS (6.5 vs 5.4 days, P =.01), and a higher incidence of requiring 96 hours or more ventilation (6.9% vs 3.6%, P =.02) in patients with COPD. Ruptured AAA affected 4.9% of patients and was strongly associated with COPD (P =.02); however, COPD did not result in a statistically significant increase in death (P =.25). CONCLUSIONS: Although COPD does not appear to increase operative death, it is associated with an increased risk of rupture. Elective repair of AAA should not be deferred in patients with COPD despite their higher LOSs and need for postoperative ventilation.

Aged↗
PubMed2001

Diagnosis and endovascular treatment of iliocaval compression syndrome.

PURPOSE: The purpose of this study was to evaluate the clinical presentation, diagnosis, and endovascular treatment of iliocaval compression syndrome (ICS). PATIENTS AND METHODS: During a 3-year period, 18 patients (17 women, 1 man; mean age, 42 years) presented with clinical and imaging findings consistent with ICS. All patients were evaluated with venography and Doppler ultrasound (DUS), 13 of 18 with intravascular pressure measurements, 12 of 18 with intravascular ultrasound, 9 of 18 with air plethysmography (APG), and 4 of 18 with magnetic resonance venography. Seventeen patients were treated with endovascular stenting, one was treated with angioplasty alone, and six received adjunct thrombolysis. RESULTS: Despite the presence of stenosis or occlusion in all cases, APG indicated no iliac vein obstruction (outflow fraction > or = 40%) in nine patients. DUS revealed acute (6) or chronic (7) unilateral iliofemoral deep venous thrombosis in 13 of 18 patients, whereas the results of five of 18 DUS studies were normal. Recanalization and stent placement (n = 17) or angioplasty (n = 1) was achieved in all patients. The average pressure gradient was 5.6 mm Hg preprocedure and 0.6 mm Hg postprocedure. The primary patency rate demonstrated with DUS (n = 17) and venography (n = 7) at 6 months was 89%. The primary patency rate at 12 months was 79%. CONCLUSIONS: ICS often presents as sudden unilateral left lower extremity pain and swelling in young to middle-aged female patients after pregnancy, surgery, or a period of inactivity. Venography, intravascular ultrasound, and magnetic resonance venography demonstrate high sensitivity, whereas APG-outflow fraction demonstrates low sensitivity in the diagnosis of ICS. Endovascular stenting and angioplasty provide safe and effective early and intermediate-term treatment of symptomatic ICS.

Adult↗
PubMed2001

Efficacy and durability of autogenous saphenous vein conduits for lower extremity arterial reconstructions in preadolescent children.

OBJECTIVE: Limb length discrepancies (LLDs) in growing children may accompany extremity arterial occlusions. Revascularization with vein grafts has been questioned because of degenerative graft changes observed at other sites. This study was undertaken to define vein graft durability and efficacy in lower extremity revascularizations in preadolescent children. STUDY DESIGN: Fourteen children (10 boys, 4 girls) with a mean age of 7.3 years (range, 2-11 years) who underwent 16 lower extremity revascularizations with greater saphenous vein grafts were subjected to follow-up with graft ultrasonography, ankle/brachial indices (ABIs) with and without exercise, and limb length determinations. A mean of 5.7 years elapsed between the onset of ischemia and operation. Arterial occlusions resulted from cardiac catheterizations (11), arteritis (1), dialysis cannulation (1), and penetrating trauma (1). Indications for operation included LLD (6), claudication (4), both LLD and claudication (3), markedly diminished ABIs with a potential for LLD (2), and a traumatic transection with hemorrhage (1). The reconstructions with 15 reversed and one in situ vein grafts included iliofemoral (11), femorofemoral (1), aortofemoral (1), femoropopliteal (1), popliteal-popliteal (1), and popliteal-posterior tibial (1) arterial bypass grafts. RESULTS: Among patent grafts available for follow-up, 36% (5 of 14) remained unchanged, 50% (7 of 14) developed nonaneurysmal dilatation, and 14% (2 of 14) exhibited nonprogressive aneurysmal expansion. One graft became occluded, and one graft was lost to follow-up. Collectively, the grafts manifest an 11.2% expansion at an average of 10.7 years postoperatively. ABIs increased from 0.75 preoperatively to 0.97, at an average of 11.0 years postoperatively. LLDs were reduced from 1.66 to 1.24 cm, at an average of 11.4 years postoperatively. CONCLUSION: Vein graft reconstructions of lower extremity arteries in preadolescent children are durable. They provide an efficacious means of restoring normal blood flow, and in 70% of children their preexisting LLDs were reduced.

Angiography, Digital Subtraction↗
PubMed2001

A clinical comparison of pneumatic compression devices: the basis for selection.

PURPOSE: The five pneumatic compression devices (PCDs) that are marketed provide mechanical protection from deep venous thrombosis (DVT). They differ with respect to patterns of compression and the length of the sleeve. Evidence linking differences to clinical outcomes is lacking. Our purpose was twofold: to evaluate each of the marketed PCDs with respect to effectiveness, compliance, and patient and nursing satisfaction and to determine whether there is a clinical basis for the selection of one device over another. METHODS: Each of the marketed devices was used exclusively for a 4-week period. Patients participated in an evaluation including venous duplex ultrasound scan, DVT risk assessment, and device evaluation. Vascular laboratory records were used to document DVT. Compliance was measured by meters installed on all pumps. A ranking matrix was stratified by compression pattern: rapid graduated sequential compression, graduated compression, and intermittent compression, and each device was rated by patients and nurses. RESULTS: The PCDs were used in 1350 cases with a DVT rate of 3.5% ranging from 2% to 9.8% depending on the method of compression. Patients with DVT were older (58 vs 54 years), had better compliance (67% vs 50%), and had more compression days (11 vs 7.2). When thigh-length sleeves were used, a greater proportion of DVT occurred in the proximal segments (71%) as compared with the number of proximal DVT when the calf-length devices were used (52%; P =.21). Devices W, X, and Y had comparable rates of DVT, which were lower than those for V and Z. Compression device W, [correction] with calf and thigh sleeves, achieved the best overall ranking largely because of high scores for patient and nurse satisfaction. CONCLUSION: Our data appear at odds with commonly held beliefs. We were unable to show a difference in DVT incidence based on the length of the device or the method of compression. Randomized studies are needed to confirm our findings and evaluate hypotheses derived from this study.

Bandages↗
PubMed2001

Computed tomographic venography is specific but not sensitive for diagnosis of acute lower-extremity deep venous thrombosis in patients with suspected pulmonary embolus.

PURPOSE: Duplex ultrasound scanning (US) is the accepted standard means of diagnosis for lower-extremity suprageniculate deep venous thrombosis (LE-DVT). Computed tomographic venography (CTV) has been proposed as an alternative modality for diagnosis of LE-DVT in patients with suspected pulmonary embolism (PE). This study compared CTV with US as a means of diagnosing acute LE-DVT. METHODS: A retrospective review of US and CTV scans from 136 patients with suspected PE who underwent both studies to exclude acute LE-DVT at a single institution was performed. Studies were reviewed and coded in a blinded manner. US was considered to be the reference test. Direct costs of each study were determined by using commercial software. RESULTS: The sensitivity and specificity rates of CTV were 71% and 93%, respectively. The positive predictive value, negative predictive value, and accuracy rates of CTV were 53%, 97%, and 90%, respectively. DVT localization was the same in eight of 10 cases in which the results of both US and CTV were positive. CTV costs and charges per study were greater than those of US by $46.88 and $602.00, respectively. CONCLUSION: CTV is specific, but has a lower sensitivity rate and positive predictive value for the diagnosis of acute LE-DVT compared with US. Additionally, CTV is more costly than US scanning. Because of the lower sensitivity rate and positive predictive value and the increased cost of CTV, US remains the screening study of choice in cases of suspected acute LE-DVT.

Costs and Cost Analysis↗
PubMed2001

Renal artery aneurysms: a 35-year clinical experience with 252 aneurysms in 168 patients.

OBJECTIVE: To define the relevance of treating renal artery aneurysms (RAAs) surgically. SUMMARY BACKGROUND DATA: Most prior definitions of the clinical, pathologic, and management features of RAAs have evolved from anecdotal reports. Controversy surrounding this clinical entity continues. METHODS: A retrospective review was undertaken of 168 patients (107 women, 61 men) with 252 RAAs encountered over 35 years at the University of Michigan Hospital. Aneurysms were solitary in 115 patients and multiple in 53 patients. Bilateral RAAs occurred in 32 patients. Associated diseases included hypertension (73%), renal artery fibrodysplasia (34%), systemic atherosclerosis (25%), and extrarenal aneurysms (6.5%). Most RAAs were saccular (79%) and noncalcified (63%). The main renal artery bifurcation was the most common site of aneurysms (60%). RAAs were often asymptomatic (55%), with a diagnosis made most often during arteriographic study for suspected renovascular hypertension (42%). RESULTS: Surgery was performed in 121 patients (average RAA size 1.5 cm), including 14 patients undergoing unilateral repair with contralateral RAA observation. The remaining 47 patients (average RAA size 1.3 cm) were not treated surgically. Operations included aneurysmectomy and angioplastic renal artery closure or segmental renal artery reimplantation, aneurysmectomy and renal artery bypass, and planned nephrectomy for unreconstructable renal arteries or advanced parenchymal disease. Eight patients underwent unplanned nephrectomy, being considered a technical failure of surgical therapy. Dialysis-dependent renal failure occurred in one patient. There were no perioperative deaths. Late follow-up (average 91 months) was available in 145 patients (86%). All but two arterial reconstructions remained clinically patent. Secondary renal artery procedures included percutaneous angioplasty, branch embolization, graft thrombectomy, and repeat bypass for late aneurysmal change of a vein conduit. Among 40 patients with clearly documented preoperative and postoperative blood pressure measurements, 60% had a significant decline in blood pressure after surgery while taking fewer antihypertensive medications. Late RAA rupture did not occur in the nonoperative patients, but no lessening of this group's hypertension was noted. CONCLUSION: Surgical therapy of RAAs in properly selected patients provides excellent long-term clinical outcomes and is often associated with decreased blood pressure.

Adolescent↗
PubMed2001

Low molecular weight protamine as nontoxic heparin/low molecular weight heparin antidote (III): preliminary in vivo evaluation of efficacy and toxicity using a canine model.

Heparin employed in cardiovascular surgeries often leads to a high incidence of bleeding complications. Protamine employed in heparin reversal, however, can cause severe adverse reactions. In an attempt to address this clinical problem, we developed low molecular weight protamine (LMWP) as a potentially effective and less toxic heparin antagonist. A homogeneous 1880-d peptide fragment, termed LMWP-TDSP5 and containing the amino acid sequence of VSRRRRRRGGRRRR, was derived directly from protamine by enzymatic digestion of protamine with thermolysin. In vitro studies demonstrated that TDSP5 was capable of neutralizing various anticoagulant functions of both heparin and commercial low molecular weight heparin preparations. In addition, TDSP5 exhibited significantly reduced crossreactivity toward mouse sera containing antiprotamine antibodies. TDSP5 showed a decrease in its potential in activating the complement system. All of these findings suggested the possibility of markedly reduced protamine toxicity for TDSP5. In this article, we conducted preliminary in vivo studies to further demonstrate the feasibility and utility of using LMWP as a nontoxic clinical protamine substitute. Dogs were chosen as test animals because they were known to magnify the typical human response to protamine. By using a full spectra of biological and clinical assays for heparin, including the anti-IIa and anti-Xa chromogenic assays and the activated partial, thromboplastin time and TCT clotting assays, TDSP5 showed that it could completely neutralize all these different anticoagulant functions of heparin in dogs. Although administration of protamine in dogs produced a significant reduction in mean arterial blood pressure (-14.9 mm Hg) and elevation in pulmonary artery systolic pressure (+5.0 mm Hg), the use of TDSP5 in dogs did not elicit any statistically significant change in any of the variables measured. Furthermore, the use of LMWP also significantly reduced the protamine-induced transient thrombocytopenic and granulocytopenic responses. The white blood cell counts and platelet counts decreased to 82.1% and 60.0% of baseline, respectively, in dogs given intravenous protamine compared to 97.8% and 88.6% of baseline in dogs receiving TDSP5. These preliminary findings indicated that LMWP could potentially provide an effective and safe means to control both heparin- and protamine-induced complications.

Animals↗
PubMed2001

P-selectin antagonism causes dose-dependent venous thrombosis inhibition.

Inhibition of P-selectin by antibody or selectin antagonist decreases inflammation and thrombosis. This study evaluates the dose-response relationship using a selectin receptor antagonist. Eight male baboons (Papio anubis) underwent inferior vena caval thrombosis using a 6 h balloon occlusion model. Three animals received 500 microg/kg P-selectin antagonist (rPSGL-Ig) and five 1 mg/kg rPSGL-Ig with or without a non-anticoagulant dose of Dalteparin. These animals were compared to our published results in this model with 4 saline controls and 8 animals that received 4 mg/kg rPSGL-Ig. A statistically significant dose-response relationship existed between rPSGL-Ig dose and thrombosis (p < 0.01), and between rPSGL-Ig dose and spontaneous recanalization (p<0.05). Inflammatory assessment revealed decreased gadolinium enhancement in all rPSGL-Ig groups compared to previously reported control, despite no significant differences in inflammatory cell extravasation. No dose of rPSGL-Ig caused anticoagulation. Selectin antagonism results in a dose-dependent decrease in thrombosis and increase in spontaneous recanalization.

Animals↗
PubMed2000

Viral IL-10 gene transfer decreases inflammation and cell adhesion molecule expression in a rat model of venous thrombosis.

Post-thrombotic inflammation probably contributes to chronic venous insufficiency, and little effective treatment exists. IL-10 is an anti-inflammatory cytokine that previously has been shown to decrease perithrombotic inflammation and thrombosis. We investigated in a rat model whether local expression of viral IL-10 (vIL-10) in a segment of vein that undergoes thrombosis would confer an anti-inflammatory effect and how this effect might be mediated. Rats underwent inferior vena cava isolation, cannulation, and instillation of saline or adenovirus encoding either beta-galactosidase or vIL-10. Two days after transfection, thrombosis was induced, 2 days after this the rats underwent gadolinium (Gd)-enhanced magnetic resonance venography exam, and the vein segments were harvested. Tissue transfection was confirmed by either RT-PCR of vIL-10 or positive 5-bromo-4-chloro-3-indolyl beta-d-galactopyranoside (X-Gal) staining. vIL-10 significantly decreased both leukocyte vein wall extravasation and area of Gd enhancement compared with those in controls, suggesting decreased inflammation. Immunohistochemistry demonstrated decreased endothelial border staining of P- and E-selectin, while ELISA of vein tissue homogenates revealed significantly decreased P- and E-selectin and ICAM-1 levels in the vIL-10 group compared with those in controls. Importantly, native cellular IL-10 was not significantly different between the groups. However, neither clot weight nor coagulation indexes, including tissue factor activity, tissue factor Ag, or von Willebrand factor levels, were significantly affected by local vIL-10 expression. These data suggest that local transfection of vIL-10 decreases venous thrombosis-associated inflammation and cell adhesion molecule expression, but does not directly affect local procoagulant activity.

Animals↗
PubMed2000

Venous thrombosis prophylaxis by inflammatory inhibition without anticoagulation therapy.

OBJECTIVE: This study was performed to determine the effectiveness of recombinant P-selectin glycoprotein ligand Ig (rPSGL-Ig) pretreatment to decrease thrombosis and inflammation in experimental venous thrombosis. rPSGL-Ig, a unique mucin-like glycoprotein, has a high affinity for P-selectin. METHODS: Twelve juvenile baboons underwent inferior vena cava (IVC) thrombosis with temporary 6-hour IVC balloon occlusion. Before balloon placement, the animals received rPSGL-Ig (4 mg/kg; n = 8) or saline solution for control (n = 4). The animals underwent evaluation with duplex ultrasound scan imaging, magnetic resonance venography (MRV), phlebography, coagulation profile, and tissue analysis at death for cytokines and vein wall leukocyte morphometrics. With the MRV results, thrombus development, thrombus resolution, and inflammation (gadolinium; square millimeters of enhancement) were assessed. RESULTS: Each animal provided two time points for evaluation (days 2 and 6 after balloon occlusion). A significant decrease in IVC thrombosis between balloons was found in the rPSGL-Ig animals (1 of 16) versus the control animals (5 of 8; P <.01). The MRV results showed significantly less enhancement in the rPSGL-Ig animals at days 2 and 6 (P <.05). Spontaneous thrombus resolution (including balloon sites) was significantly greater from day 2 to day 6 in the rPSGL-Ig animals versus the control animals (23% vs 2%; P <.001), without pulmonary embolism. Lower interleukin-8, platelet factor IV, and monocyte chemotactic protein-1 levels were found in rPSGL-Ig vein walls without significant differences in vein wall leukocyte morphometrics. There were significantly lower D-dimer levels in the rPSGL-Ig-treated animals (P <.05), but there were no differences in measurements of coagulation. Adequate circulating rPSGL-Ig levels were documented. CONCLUSION: Pretreatment with rPSGL-Ig results in: (1) a significant inhibition of thrombosis and vein wall inflammation; (2) a decrease in vein wall cytokine expression; and (3) a promotion of thrombus resolution. Inflammatory inhibition by rPSGL-Ig without anticoagulation therapy provides effective venous thrombosis prophylaxis in experimental venous thrombosis.

Animals↗
PubMed2000

Incidence of femoral and popliteal artery aneurysms in patients with abdominal aortic aneurysms.

OBJECTIVE: The purpose of this study was to determine the incidence of femoral and popliteal aneurysms in men and women who have abdominal aortic aneurysms (AAAs) and to assess potential etiologic differences in patients with and without these lower extremity aneurysms. METHODS: We studied 313 consecutive patients with AAAs encountered from 1995 to 1998 who underwent prospective ultrasound scanning to detect the presence or absence of femoral and popliteal aneurysms. Patients with and without these extremity aneurysms were compared for differences in potential etiologic risk factors with each other and with a statewide population of patients with AAAs. RESULTS: A total of 51 femoral and popliteal aneurysms were encountered, all occurring in male patients. Among the 251 men with AAAs, the incidence of femoral or popliteal aneurysms was 14%, compared with 0% among the 62 women with AAAs (P <.01). A family history of aneurysmal disease was present in only one (3%) of the 36 men with these extremity arterial aneurysms, a significant finding (P <.01) when compared with the family history that was positive for aneurysmal disease in 14 women (23%). Peripheral arterial occlusive disease affected 14 (39%) of the 36 men with peripheral arterial aneurysms versus 20 (9%) of the 215 men without these aneurysms (P <.01). Most other etiologic variables studied proved not to be different among the various groups of patients examined. CONCLUSION: The incidence of femoral and popliteal aneurysms in persons with AAAs appears higher than that noted previously. Femoral and popliteal aneurysmal disease preferentially affects men; however, the basis for this sex difference is unknown. Few common etiologic factors differed between men with and without these extremity aneurysms. Most femoral and popliteal artery aneurysms in this study were undetectable on physical examination, suggesting that ultrasound scanning is appropriate in the recognition of peripheral aneurysms among men with AAAs.

Aged↗