Bruce L. Gewertz

Harbor-UCLA Medical Center, Torrance, California, United States

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Publications (90)212.21 Total impact

  • Tina R. Desai · Joshua A. Tepper · Bruce L. Gewertz
    Vascular Surgery: Basic Science and Clinical Correlations, Second Edition, 10/2007: pages 215 - 224; , ISBN: 9780470987094
  • Bruce L Gewertz
    Archives of Surgery 09/2006; 141(8):812-4. DOI:10.1001/archsurg.141.8.812 · 4.30 Impact Factor
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    ABSTRACT: To identify features on B-mode ultrasonography (US) prevalent in symptomatic plaques and correlate these findings with histopathologic markers of plaque instability. Carotid endarterectomy (CEA) plaques from symptomatic and asymptomatic patients with critical stenoses (>70%) were qualitatively assessed using preoperative B-mode US for echolucency and calcific acoustic shadowing. US echolucency was quantitated ex vivo using computerized techniques for gray-scale median (GSM) analysis. Histopathologic correlates for US plaque echolucency (percentage of necrotic core area) and acoustic shadowing (percentage of calcification area) were determined. Fifty CEA plaques were collected from 48 patients (46 unilateral and two bilateral); 26 of these plaques were from symptomatic patients. Age, degree of stenosis, and atherosclerotic risk factors were similar for the symptomatic and asymptomatic patients. Using preoperative B-mode US, 58%, 35%, and 7% of symptomatic plaques and 18%, 41%, and 41% of asymptomatic plaques were found to be echolucent, echogenic, and calcific, respectively (P < .05). Using ex-vivo B-mode US and GSM analysis, symptomatic plaques were more echolucent (41 +/- 19) than asymptomatic plaques (60 +/- 13), P < .03. A strong inverse correlation was found between the percent plaque necrotic area core and GSM (R = -0.9, P < .001). Percentage of calcification area in plaques with acoustic shadowing was 66% and only 27% in those without acoustic shadowing (P < .05). Using B-mode US, symptomatic plaques are more echolucent and less calcified than asymptomatic plaques and are associated with a greater degree of histopathologic plaque necrosis. Such features are indicative of plaque instability and should be considered in the decision-making algorithm when selecting patients with high-grade asymptomatic carotid stenosis for intervention.
    Journal of Vascular Surgery 09/2005; 42(3):435-41. DOI:10.1016/j.jvs.2005.05.033 · 2.98 Impact Factor
  • John B Seal · Bruce L Gewertz
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    ABSTRACT: Microvascular dysfunction mediates many of the local and systemic consequences of ischemic-reperfusion (I/R) injury, with a spectrum of changes specific to arterioles, capillaries, and venules. This review discusses the specific changes in the endothelium during I/R injury; describes the differential responses of the various levels of the vasculature including arterioles, capillaries, and venules; and explores mechanisms for remote organ injury. Vascular dysfunction is largely a consequence of changes in the endothelial cells themselves, affecting the integrity of barrier function, cytokine and adhesion molecule expression, and vascular tone. The bioavailability of nitric oxide, an important mediator of vasodilation, is profoundly decreased during the reperfusion period, resulting in impaired vasodilation of arterioles. Release of inflammatory mediators and increased expression of adhesion molecules initiate inflammatory and coagulation cascades that culminate in the occlusion of capillaries, known as the "no-reflow''" phenomenon. In postcapillary venules, the recruitment and transmigration of leukocytes further compromise the integrity of the endothelial barrier and increase the oxidative burden, resulting in leakage and tissue edema. I/R injury can have significant and untoward consequences beyond the affected tissue, with such conditions as systemic inflammatory response syndrome. This review highlights recent progress in understanding of the varied phenomena of vascular dysfunction in I/R injury and some promising advances in the understanding and application of ischemic preconditioning and other potential therapies.
    Annals of Vascular Surgery 08/2005; 19(4):572-84. DOI:10.1007/s10016-005-4616-7 · 1.03 Impact Factor
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    ABSTRACT: Open repair of abdominal aortic aneurysms (AAAs) or occlusive disease can be complicated by pseudoaneurysm formation and aneurysmal dilatation of native vessels. Reports of reoperation for these new lesions have a mortality rate of 5-17% electively, and 24-88% if ruptured. These complications are commonly several years after initial repair, and progression of other comorbidities can further complicate a repeat exploration. The authors reviewed 5 cases of late complications of open aortic bypass surgery treated with endovascular stent grafting as an alternative to reexploration in patients with increased risk for morbidity and mortality. Over a 6-year experience, 5 patients underwent endovascular stent grafting to repair paraanastomotic aneurysms. Patient records were reviewed and clinical cardiac risk evaluation was performed. Follow-up clinic notes and computed tomography (CT) scans were evaluated. Between October 1996 and February 2002, 5 patients underwent 6 endovascular procedures to repair paraanastomotic aneurysms. Mean period between interventions was 16.6 +/-6.27 years (range 10-25); mean age at endovascular procedure 74.2 +/-6.37 years (range 67-84). Cardiac clinical risk index increased in 80% of patients by Goldman Risk Index and in 40% by the Modified Cardiac Risk Index. On completion angiography, there was complete exclusion of the paraanastomotic aneurysms in all cases (100%). Length of postoperative stay was 1.5 +/-0.547 days. Mean estimated blood loss at conclusion of endovascular procedure was 577 +/-546.504 cc (range, 60 cc-1,500 cc). Mean follow-up was 24.4 +/-24.593 months (range, 5-67 months). On repeat imaging, all stent grafts remain patent without rupture or endoleak. Endovascular stent grafting to repair late complications of open AAA repair is a viable alternative to reexploration in patients with significant comorbidities. These procedures can be performed without violating the previous surgical planes of sites. The operations can be performed under local anesthesia and with reduced hospitalizations. In patients with increased risk factors, endovascular stent grafting is a less morbid alternative to open surgical techniques.
    Vascular and Endovascular Surgery 01/2005; 39(3):221-8. · 0.77 Impact Factor
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    ABSTRACT: We undertook this study to quantitate differences in the degree of calcification between symptomatic and asymptomatic plaques removed at carotid endarterectomy (CEA) and to determine associated extent of plaque macrophage infiltration, a histopathologic feature of plaque instability. CEA plaques (n = 48) were imaged at 1.25-mm intervals with spiral computed tomography (CT; 10-15 images per plaque). Indications for CEA were transient ischemic attack (n = 16), stroke (n = 5), amaurosis (n = 4), and critical asymptomatic stenosis (n = 23). The percent area calcification for each plaque was determined in spiral CT serial sections and averaged for each plaque. In 31 of 48 plaques macrophage infiltration was quantitated in corresponding histologic sections with immunohistochemical techniques. The mean (+/- SD) age of patients with symptomatic and asymptomatic plaques was 66 +/- 7 years vs 71 +/- 7 years, respectively, and degree of stenosis was 76% versus 82%, respectively (P =.05). Atherosclerosis risk factors were similar between groups. Percent plaque area calcification was twofold greater in asymptomatic versus symptomatic plaques (48% +/- 19% vs 24% +/- 20%, respectively; P <.05). At receiver operating characteristic curve analysis, 80% of symptomatic plaques were below and 87% of asymptomatic plaques were above a cutoff point of 30% plaque area calcification. Macrophage burden was greater in the symptomatic plaques than in the asymptomatic plaques (52% vs 23%; P <.03). A strong inverse relationship between the degree of plaque calcification and macrophage infiltration was found in critical carotid stenoses (r = -0.87; P <.001). Symptomatic plaques are less calcified and more inflamed than asymptomatic plaques. Regardless of clinical outcome, a strong inverse correlation was found between the extent of carotid plaque calcification and the intensity of plaque fibrous cap inflammation as determined by the degree of macrophage infiltration. Carotid plaque calcification is associated with plaque stability, and is a potential spiral CT in vivo quantitative marker for cerebrovascular ischemic event risk.
    Journal of Vascular Surgery 08/2004; 40(2):262-9. DOI:10.1016/j.jvs.2004.04.025 · 2.98 Impact Factor
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    ABSTRACT: The purpose of this study was to examine the outcome of patients in whom an infrainguinal bypass graft failed. This was a retrospective analysis of consecutive patients undergoing infrainguinal bypass grafting in a single institution over 8 years. Six hundred thirty-one infrainguinal bypass grafts were placed in 578 limbs in 503 patients during the study period. The indication for surgery was limb-threatening ischemia in 533 patients (85%); nonautologous conduits were used in 259 patients (41%), and 144 (23%) were repeat operations. After a mean follow-up of 28 +/- 1 months (median, 23 months; range, 0-99 months), 167 grafts (26%) had failed secondarily. The rate of limb salvage in patients with graft failure was poor, only 50% +/- 5% at 2 years after failure. The 2-year limb salvage rate depended on the initial indication for bypass grafting: 100% in patients with claudication (n = 16), 55% +/- 8% in patients with rest pain (n = 49), and 34% +/- 6% in patients with tissue loss (n = 73; P <.001). The prospect for limb salvage also depended on the duration that the graft remained patent. Early graft failure (<30 days; n = 25) carried a poor prognosis, with 2-year limb salvage of only 25% +/- 10%; limb salvage was 53% +/- 5% after intermediate graft failure (<2 years, n = 110) and 79% +/- 10% after late failure (>2 years, n = 15; P =.04). Multivariate analysis revealed shorter patency interval before failure (P =.006), use of warfarin sodium (Coumadin) postoperatively (P =.006), and infrapopliteal distal anastomosis (P =.01) as significant predictors for ultimate limb loss. The overall prognosis for limb salvage in patients with failed infrainguinal bypass grafts is poor, particularly in patients with grafts placed because of tissue loss and those with early graft failure.
    Journal of Vascular Surgery 05/2004; 39(5):951-7. DOI:10.1016/j.jvs.2004.01.027 · 2.98 Impact Factor
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    ABSTRACT: The increased complexity of redo infrainguinal bypass procedures can result in prolonged operative time and increased morbidity. This review was undertaken to compare outcomes from primary and redo bypass procedures and to identify factors predictive of graft failure and limb loss after redo bypass. All infrainguinal bypasses ( n = 468) from 1995 to 1999 were reviewed. A total of 367 primary bypasses in 317 patients were compared to 101 redo grafts in 84 patients with previously failed bypasses. Risk factors and types of procedures were compared using Student's t-test and the chi(2) test. Patency and limb salvage were compared using life-table analysis. Patients requiring redo bypasses were less likely to have diabetes and end-stage renal disease. Two-year patency (66 +/- 4% primary vs. 55 +/- 7% redo, p = 0.13) and limb salvage (75 +/- 3% primary vs. 72 +/- 6% secondary, p = 0.43) were comparable between primary and redo bypass groups. Female gender was predictive of redo graft failure (2-year patency 73 +/- 8% male vs. 39 +/- 9% female, p = 0.01). Clinical indications that predicted failure of a redo bypass included thrombosis of an autologous graft (1-year patency 71 +/- 7% previous prosthetic vs. 49 +/- 10% previous autologous, p = 0.004), thrombosis of an infrageniculate bypass (2-year patency 65 +/- 10% suprageniculate vs. 46 +/- 9% infrageniculate, p = 0.044), and a limb salvage indication for the primary operation (2-year patency 86 +/- 9% claudication vs. 44 +/- 8% limb salvage, p = 0.008). When a primary bypass fails despite the use of optimal conduit (autologous vein) and an infrageniculate target vessel, the redo bypass has a higher risk of failure, particularly in female patients. Nonetheless, patency and limb salvage rates justify an attempt at revascularization after failed primary bypass.
    Annals of Vascular Surgery 10/2003; 17(5):492-502. DOI:10.1007/s10016-003-0040-z · 1.03 Impact Factor
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    ABSTRACT: The purpose of this study was to test the hypothesis that the long-term outcome of infrainguinal bypass grafting in patients with congenital or acquired hypercoagulability is inferior to the results in patients without documented clotting disorders. The study was a retrospective analysis of consecutive patients from January 1994 to January 2001. Five hundred eighty-two infrainguinal bypass grafts were created in 456 patients. Indication for surgery was limb-threatening ischemia in 84%; prosthetic conduits were implanted in 38%. Seventy-four grafts were created in 57 patients with one or more serologically proven hypercoagulable states, including heparin-induced platelet aggregation (n = 37), anticardiolipin antibodies (n = 11), lupus anticoagulant (n = 8), protein C or S deficiency (n = 7), antithrombin III deficiency (n = 3), and factor V Leiden mutation (n = 1). Patients with hypercoagulability were younger (63 +/- 2 years versus 69 +/- 1 years; P =.007), more likely to have undergone prior revascularization attempts (38% versus 21%; P =.003), and more likely to have chronic anticoagulation therapy after surgery (46% versus 25%; P =.001). After 5 years (median follow-up, 19 months), patients with hypercoagulability had poorer primary patency (28% +/- 7% versus 35% +/- 5%; P =.004), primary assisted patency (37% +/- 7% versus 45% +/- 6%; P =.0001), secondary patency (41% +/- 7% versus 53% +/- 6%; P =.0001), limb salvage (55% +/- 8% versus 67% +/- 6%; P =.009), and survival (61% +/- 8% versus 74% +/- 4%; P =.02) rates. Multivariate analysis identified only prosthetic conduit choice (P =.0001), hypercoagulability (P =.0003), and limb salvage indication (P =.01) as independent predictors of graft failure. Patients with serologically proven hypercoagulability have inferior long-term patency, limb salvage, and survival rates after infrainguinal bypass. The high prevalence rate (13%) of diverse hypercoagulable states in this patient population supports serologic screening, especially in referral practices.
    Journal of Vascular Surgery 03/2003; 37(2):301-6. DOI:10.1067/mva.2003.114 · 2.98 Impact Factor
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    ABSTRACT: Although early postoperative duplex scanning has become routine after carotid endarterectomy (CEA), it is unclear whether the results of these scans alter clinical management. The purpose of this study was to critically examine the usefulness of early postoperative duplex scans in evaluating the ipsilateral carotid artery (for technical perfection) as well as the contralateral carotid artery (for potential velocity changes after improvements in ipsilateral flow). Consecutive patients undergoing CEA between January 1995 and June 1999 in a tertiary hospital setting were studied. Patients underwent early postoperative duplex scanning according to the discretion of the operating surgeon and the availability of the patient. In 212 patients 236 CEAs were performed with selective use of patch closure (49%), intraluminal shunting (19%), and intraoperative completion imaging studies (14%). Neurologic complications included 3 transient ischemic attacks (TIAs) (1.3%), 3 nondisabling strokes (1.3%), and 3 disabling strokes (1.3%). There was 1 30-day death from myocardial infarction. Patients were followed up for a median of 18 months (range 0-72 months). Sixty-five percent of patients undergoing uncomplicated CEA (147/227) underwent early duplex surveillance within 6 months of operation. Unsuspected sonographic abnormalities were discovered in 8 patients (5%), including 7 cases of mild internal carotid artery (ICA) stenosis (>50% by velocity criteria) and 1 case of common carotid artery (CCA) stenosis (intimal flap). None of the patients with ICA stenosis developed symptoms or required operation at any time. The CCA intimal flap was electively repaired without complication. Postoperative changes in velocity in the contralateral ICA were found in 8/48 (17%) cases. There were 3 cases of increased velocity, upgrading 1 from 0-49% to 50-79% stenosis and upgrading 2 from 50-79% to 80-99% stenosis. The latter patients both underwent uneventful contralateral CEA. There were 6 cases of decreased velocity, resulting in downgrading of stenoses from 50-79% to 0-49% (n=5) or from 80-99% to 50-79% (n=1). Only the latter patient underwent contralateral CEA; the remainder have been followed up without intervention. Early scanning appeared to offer no clinical benefit; survival and neurologic outcome were the same in the 135 patients scanned within the first 6 months as in the 68 patients whose first postoperative scan occurred later (4-year neurologic event rate 0% in both groups; patient survival with early duplex 98 +/- 1.5%, without early duplex 96 +/- 2.6%; = NS). Early ipsilateral duplex abnormalities following CEA are infrequent in asymptomatic patients and, even if found, rarely alter management. Patients with bilateral stenosis being considered for contralateral CEA should undergo repeat duplex scanning after the first operation, because of the significant rate (19%) of contralateral velocity changes induced by ipsilateral CEA.
    Vascular and Endovascular Surgery 01/2003; 36(2):115-22. DOI:10.1177/153857440203600206 · 0.77 Impact Factor
  • Kellie R Brown · Tina R Desai · Lewis B Schwartz · Bruce L Gewertz
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    ABSTRACT: Carotid artery angioplasty and stenting is gaining popularity, yet the natural history and optimal treatment for recurrent stenoses within stents are not known. Recurrent stenosis rates are not well characterized, with rates between 0 and 33% reported within the first year. Treatment of these lesions with repeat angioplasty may not be feasible or desirable, leading to operative interventions. We present two cases of asymptomatic high-grade in-stent restenosis treated successfully with carotid artery bypass using PTFE.
    Annals of Vascular Surgery 10/2002; 16(5):575-8. DOI:10.1007/s10016-001-0279-1 · 1.03 Impact Factor
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    ABSTRACT: Infrageniculate (below-knee) bypass using all-autogenous composite vein requires multiple incisions, venovenostomy, and prolonged operating time. The purpose of this study was to evaluate the long-term results of this procedure, with comparisons to grafts created from single-segment greater saphenous vein (GSV) or polytetrafluoroethylene (PTFE). A total of 362 consecutive infrainguinal bypass grafts with infrageniculate distal target arteries were created in 283 patients in a single institution between January 1995 and December 2000. Comorbid conditions were common, including diabetes (58%), coronary artery disease (56%), prior lower extremity revascularization (41%), end-stage renal failure (20%), and prior coronary artery bypass grafting (18%). The indication for revascularization was limb salvage in 93% of cases. The grafts were constructed from single segments of GSV (n = 239), from two or more vein segments resulting in an all-autogenous composite graft (n = 61), or from PTFE (n = 62). All-autogenous composite grafts were constructed using segments of ipsilateral or contralateral GSV (n = 49), upper extremity vein (n = 23), superficial femoral vein (n = 7), or lesser saphenous vein (n = 5). Infrageniculate all-autogenous composite vein grafts exhibited similar long-term results to those of GSV grafts, and far superior results to those of PTFE grafts. For patients with available autogenous segments, the all-autogenous composite vein graft is the conduit of choice.
    Annals of Vascular Surgery 10/2002; 16(5):618-23. DOI:10.1007/s10016-001-0266-6 · 1.03 Impact Factor
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    ABSTRACT: A 77 year-old woman with mild osteoarthritis and Sjögren's Syndrome presented to an outside hospital with mild abdominal and back pain. The initial computed tomography (CT) scan was essentially negative. The repeat CT scan after 1 week of medical therapy was suspicious for a contained rupture of the visceral aorta. She was emergently transferred to the University of Chicago. Emergent aortography confirmed the diagnosis and revealed wide patency of the visceral and renal arteries. Upon exploration, there was obvious rupture of the entire right posterior aortic wall at the level of the celiac axis with a large right retroperitoneal hematoma. Aorto-aortic bypass was performed. The visceral and renal vessels were revascularized using separate jump grafts to this 'parallel aorta'. The patient tolerated the procedure well and was discharged after 12 days. Pathologic examination of the aortic wall was essentially negative. She is well on follow-up after 20 months. To our knowledge, this is the second reported case of spontaneous contained rupture of the visceral aorta.
    Cardiovascular Surgery 07/2002; 10(3):279-83. DOI:10.1016/S0967-2109(02)00009-1
  • Tina R Desai · Nicholas J Leeper · Karen L Hynes · Bruce L Gewertz
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    ABSTRACT: Elevated levels of interleukin-6 (IL-6) have been identified in a variety of systemic inflammatory states that are associated with endothelial barrier dysfunction, but the specific effect of IL-6 on endothelial permeability and the mechanism of action have not been fully examined. The current study evaluated the effect of IL-6 on endothelial permeability and on the distribution of the tight junctional protein ZO-1 and cytoskeletal actin. We also assessed the role of protein kinase C (PKC) in this process. Confluent monolayers of human umbilical vein endothelial cells (n = 6) were exposed to IL-6 (50-500 ng/ml) in the presence or absence of the PKC inhibitor Gö6976 (0.1 microM). Transendothelial electrical resistance (TEER) was measured at the onset of exposure and at 6-h intervals and compared with that of control cells using ANOVA with a Bonferroni multiple comparison test. Additional monolayers were exposed to IL-6, stained for ZO-1 and F-actin, and evaluated via fluorescence microscopy. Interleukin-6 increased endothelial permeability as measured by TEER in a dose- and time-dependent manner. In the presence of PKC inhibitor, the IL-6-mediated increase in permeability was attenuated (18-h TEER 73% of control with IL-6 exposure vs 95% of control with IL-6 + Gö6976 inhibitor, P < 0.01). Microscopy revealed that permeability changes were accompanied by a redistribution of the tight junctional protein ZO-1 and cytoskeletal actin, increased cell contraction, and disorganization of the intercellular borders. Conclusions. The inflammatory cytokine IL-6 is an important mediator of increased endothelial permeability via alterations in the ultrastructural distribution of tight junctions and morphologic changes in cell shape. PKC is a critical intracellular messenger in these IL-6-mediated changes. A better understanding of this mechanism should allow the determination of rational treatment strategies for endothelial barrier dysfunction which occurs in inflammatory states.
    Journal of Surgical Research 05/2002; 104(2):118-23. DOI:10.1006/jsre.2002.6415 · 2.12 Impact Factor
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    ABSTRACT: Endothelial cells increase their secretion of the cytokine interleukin-6 (IL-6) during hypoxia, which then acts in an autocrine fashion to increase the permeability of cell monolayers. These responses are attenuated by antioxidants, suggesting that reactive oxygen species (ROS) participate in signaling in hypoxic endothelium. We tested whether mitochondria are responsible for these ROS in human umbilical vein endothelial cells exposed to hypoxia. Oxidation of the probe 2', 7'-dichlorodihydrofluorescein to fluorescent dichlorofluorescein or the probe dihydroethidium was used to assess oxidant signaling, whereas permeability was assessed by using transendothelial electrical resistance. Hypoxia elicited increases in dichlorofluorescein and dihydroethidium fluorescence that were abrogated by the mitochondrial electron transport (ET) inhibitors rotenone (2 micromol/L) and diphenyleneiodonium (5 micromol/L). The same ET inhibitors also attenuated hypoxia-induced increases in nuclear factor-kappaB (NF-kappaB) activation, although they did not abrogate NF-kappaB activation in response to endotoxin (lipopolysaccharide). ET inhibition also abolished the hypoxia-induced increases in IL-6 mRNA expression, hypoxia-stimulated IL-6 secretion into the media, and the hypoxia-induced increases in transendothelial electrical resistance of human umbilical vein endothelial cell monolayers. By contrast, the above responses to hypoxia were not significantly affected by treatment with the NAD(P)H oxidase inhibitor apocynin (30 micromol/L), the xanthine oxidase inhibitor allopurinol (100 micromol/L), or the NO synthase inhibitor N-nitro-L-arginine (100 micromol/L). We conclude that ROS signals originating from the mitochondrial ET chain trigger the increase in NF-kappaB activation, the transcriptional activation of IL-6, the secretion of IL-6 into the cell culture media, and the increases in endothelial permeability observed during hypoxia.
    Arteriosclerosis Thrombosis and Vascular Biology 05/2002; 22(4):566-73. · 5.53 Impact Factor
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    ABSTRACT: Many surgeons consider PTFE to be the conduit of choice for above-knee femoropopliteal bypass grafting, since PTFE is relatively easy to implant and spares autogenous saphenous vein (ASV) for subsequent peripheral or coronary artery bypass grafting (CABG). This practice has recently been challenged, as some studies have suggested that ASV may exhibit superior patency in certain patient subgroups. The purpose of this retrospective study was to examine the contemporary outcome of above-knee femoropopliteal bypass grafting in patients with limb-threatening ischemia. Between January 1995 and December 2000, 159 above-knee femoropopliteal bypass grafts were created for limb-threatening ischemia (rest pain or tissue loss). There was a high incidence of comorbid illness, including open foot wounds at the time of operation (62%), hypertension (58%), coronary artery disease (53%), diabetes mellitus (36%), cerebrovascular disease (23%), prior contralateral bypass or amputation (21%), disadvantaged or "blind" outflow (19%), prior ipsilateral bypass (14%), prior CABG (11%) end-stage renal failure (7%). The use of PTFE predominated (n = 11), with a minority of grafts comprising single-segment ipsilateral or contralateral ASV (n = 18). Although the small number of patients undergoing ASV grafting limited the statistical power of comparison, our results suggest that above-knee ASV performs better than PTFE in patients with limb-threatening ischemia.
    Annals of Vascular Surgery 02/2002; 16(1):95-101. DOI:10.1007/s10016-001-0134-4 · 1.03 Impact Factor
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    ABSTRACT: The current study was undertaken to evaluate the potential influence of gender on iliac angioplasty outcomes. All iliac angioplasty procedures performed at a tertiary care center from 1994 to 1999 were reviewed. One hundred four angioplasties with or without stenting were performed in 44 women (56 limbs) and 40 men (48 limbs). Age and atherosclerotic risk factors were similar in men and women. Iliac angioplasty was performed for limb salvage in 41% of patients (39% female vs. 44% male; p = 0.65). There were no differences in degree of stenosis, lesion length, or initial angioplasty site. Female iliac arteries were more likely to be occluded (21% vs. 6%; p = 0.03); mean iliac artery luminal diameter was smaller in women than in men (6.5 +/- 0.5 mm vs. 8.2 +/- 0.6 mm; p < 0.001). After a median follow-up of 13 months, there were no significant differences in 2-year primary patency, endovascular primary-assisted patency, or limb salvage rates between women and men. Despite having smaller iliac arteries and a higher incidence of arterial occlusion before treatment, women had outcomes similar to those of men after iliac angioplasty. The current results support the initial use of angioplasty to treat common and external iliac artery occlusive disease in both women and men.
    Annals of Vascular Surgery 01/2002; 16(1):55-60. DOI:10.1007/s10016-001-0131-7 · 1.03 Impact Factor
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    ABSTRACT: Infrainguinal bypass grafting for limb-threatening ischemia in patients with end-stage renal disease is generally thought to be associated with increased operative risk and poor long-term outcome. This retrospective study was undertaken to examine the modern-era, long-term results of infrainguinal bypass grafting in dialysis-dependent patients. Over the past 5 years in a single institution, 425 lower extremities (368 consecutive patients) were revascularized for the indication of limb salvage. Sixty-four patients (82 limbs) were dialysis-dependent at the time of revascularization, and this group was analyzed separately. They exhibited statistically significant higher incidences of diabetes (83% vs 56%; P <.001), hypertension (91% vs 74%; P <.001), and more distal vascular disease, which required a greater proportion of proximal anastomoses at the popliteal level (24% vs 11%; P <.01) and distal anastomoses at the infrapopliteal level (75% vs 65%; P <.05). Despite the higher prevalence of comorbid conditions and distal disease in patients with renal failure, their perioperative 30-day mortality rate remained low (4.9%) and was not significantly different from that in patients with functioning kidneys (2.9%; P = not significant). After a median follow-up of 11 months (range, 0-60 months), the 3-year autogenous conduit secondary graft patency in patients with renal failure was no different than in patients with functioning kidneys (67% +/- 9% vs 64% +/- 5%; P = not significant). Nonautogenous conduits in dialysis-dependent patients exhibited a significantly poorer outcome with only 27% +/- 12% remaining secondarily patent at 2 years. As expected, both limb salvage and patient survival were significantly less in patients with renal faiture, although both exceeded 50% at 3 years (limb salvage 59% +/- 8% vs 68% +/- 5%; P <.05; patient survival 60% +/- 8% vs 86% +/- 4%; P <.001). The often-quoted phenomenon of limb loss, despite a patent bypass graft, occurred infrequently in this study (n = 3 of 82 limbs). Infrainguinal revascularization can be performed in dialysis-dependent patients with acceptable perioperative and long-term results, especially in patients in whom adequate autologous conduit is available.
    Journal of Vascular Surgery 07/2001; 34(1):27-33. DOI:10.1067/mva.2001.116350 · 2.98 Impact Factor
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    ABSTRACT: Infrainguinal graft patency and limb salvage are adversely affected by severely compromised outflow. Retrospective review of all infrainguinal bypass procedures performed at a single institution during a 5-year period. University teaching hospital. Two hundred seventy-four patients underwent infrainguinal bypass for limb salvage (351 grafts in 307 limbs). All infrainguinal bypasses originated from a femoral artery. The distal anastomosis in 279 grafts was located in an artery with at least 1 patent outflow vessel with anatomically normal end-artery runoff (Society for Vascular Surgery/International Society for Cardiovascular Surgery ad hoc committee runoff score, 1-9). The distal anastomosis of 72 grafts was located in an artery with only collateral outflow ("blind bypass"; runoff score, 10). Perioperative morbidity and mortality, primary-assisted and secondary graft patency, limb salvage, and survival. All data are presented as mean +/- SEM. Patients undergoing blind bypass were older (age, 70 +/- 2 vs. 66 +/- 1 years; P <.05) and had a higher incidence of hypertension (90% vs 70%; P <.05) and end-stage renal disease (24% vs. 13%; P <.05). Comparing patients undergoing blind bypass to bypass with at least 1 patent outflow vessel, there were no differences in the use of nonautogenous conduits (50% vs 59%; P =.21) or postoperative warfarin (30% vs 32%; P =.69), or in perioperative mortality rates (2.7% vs 3.2%; P =.79). After a median follow-up of 13 months (range, 0-60 months), 2-year secondary graft patency for the entire group was 63% +/- 4%. The secondary patency rate of blind bypass grafts was no different from that of grafts with at least 1 patent outflow vessel (67% +/- 7% vs. 64% +/- 4%; P was not significant). However, the 2-year limb salvage rate in limbs with blind outflow was significantly worse than in limbs with at least 1 patent outflow vessel (67% +/- 7% vs. 76% +/- 3%; P =.04). Acceptable long-term patency rates can be achieved in infrainguinal bypass grafts with blind outflow, although blind outflow remains a marker for subsequent limb loss in the chronically ischemic leg.
    Archives of Surgery 06/2001; 136(6):635-42. DOI:10.1001/archsurg.136.6.635 · 4.30 Impact Factor
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    ABSTRACT: Although increased application of percutaneous renal artery angioplasty and stenting has facilitated nonoperative renal revascularization, patient outcomes after failed angioplasty are not established. Renal artery revascularization was performed in 31 patients (38 arteries) from 1993 to 1999. Twenty patients underwent primary surgical repair, and 11 patients underwent secondary reconstruction after angioplasty (n = 7) or angioplasty and stenting (n = 4). Before operation, all patients had severe hypertension (blood pressure 166+/-5.2/92 +/- 2.7 mm Hg) that required an average of 3.0 +/- 0.2 medications for control. In addition, 12 patients (primary 45% vs secondary 27%; P = NS) had evidence of renal insufficiency (creatinine > or =1.7 mg/dL). There was no difference between primary and secondary procedures in the length of hospital stay (12+/- 1.4 vs. 12+/-3.2 days; P = NS), major morbidity (10% vs. 18%; P = NS) or perioperative mortality (overall mortality 2 of 31; primary 5% vs secondary 9%; P = NS). The majority of patients demonstrated improvement or cure of hypertension (primary 94% vs secondary 90%; P = NS) and stable or decreased creatinine (primary 74% vs secondary 82%; P = not significant). Overall survival (mean follow-up 22+/-3.5 months) was 89%+/-5.7%. Although this surgical series does not address the true outcomes of renal artery angioplasty, the results suggest that renal artery angioplasty does not prejudice subsequent surgical outcomes in patients who are carefully followed after angioplasty.
    Surgery 10/2000; 128(4):717-25. DOI:10.1067/msy.2000.108221 · 3.11 Impact Factor

Publication Stats

2k Citations
212.21 Total Impact Points

Institutions

  • 2007
    • Harbor-UCLA Medical Center
      Torrance, California, United States
  • 1983–2006
    • University of Chicago
      • • Department of Surgery
      • • Department of Chemistry
      Chicago, IL, United States
  • 1992–1998
    • University of Illinois at Chicago
      • Department of Surgery (Chicago)
      Chicago, Illinois, United States
  • 1986
    • The University of Chicago Medical Center
      • Department of Neurology
      Chicago, Illinois, United States