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1.
J Vasc Surg ; 75(1S): 109S-120S, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34023430

RESUMEN

The Society for Vascular Surgery clinical practice guidelines on popliteal artery aneurysms (PAAs) leverage the work of a panel of experts chosen by the Society for Vascular Surgery to review the current world literature as it applies to PAAs to extract the most salient, evidence-based recommendations for the treatment of these patients. These guidelines focus on PAA screening, indications for intervention, choice of repair strategy, management of asymptomatic and symptomatic PAAs (including those presenting with acute limb ischemia), and follow-up of both untreated and treated PAAs. They offer long-awaited evidence-based recommendations for physicians taking care of these patients.


Asunto(s)
Aneurisma/cirugía , Procedimientos Endovasculares/normas , Arteria Poplítea/cirugía , Procedimientos Quirúrgicos Vasculares/normas , Aneurisma/diagnóstico por imagen , Aneurisma/epidemiología , Toma de Decisiones Clínicas , Consenso , Procedimientos Endovasculares/efectos adversos , Medicina Basada en la Evidencia , Humanos , Arteria Poplítea/diagnóstico por imagen , Medición de Riesgo , Factores de Riesgo , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/efectos adversos
2.
Ann Vasc Surg ; 83: 26-34, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35257915

RESUMEN

BACKGROUND: With the risk of recurrent ischemic stroke being highest in the first week following transient ischemic attack or stroke, the current guidelines of "early" endarterectomy within 2 weeks still leave potential vulnerability for patients with a significant bifurcation lesion and a new stroke. The intent of this analysis is to determine the safety of carotid endarterectomy even earlier than the current guidelines, based on a single surgeon experience of more than 12 years. SUMMARY BACKGROUND DATA: Although there has been a progressive movement toward earlier intervention following acute ischemic stroke in the presence of a culprit bifurcation lesion, most of the recommendations still are for performance of endarterectomy within two weeks following the event. This compression is welcome but given that the risk of recurrent stroke is highest within the first week following stroke, there is a reason to evaluate an earlier time frame for carotid endarterectomy (CEA). METHODS: A retrospective review of all CEA performed by a single surgeon over a 12-year period was performed. Patient demographics, Modified Rankin score (mRS) whenever documented, degree of internal carotid artery (ICA) stenosis, and preoperative neurologic symptoms were recorded. The 30-day outcomes including stroke, transient ischemic attack, death, and other major complications were tabulated. RESULTS: A total of 444 patients (mean age 74 ± 10.1) underwent a total of 465 CEAs. Two hundred and twenty-eight (49%) CEAs were for a symptomatic disease: of these, 194 had a documented stroke. One hundred and eighty-one stroke patients (93%) underwent CEA within 72 hr and the remaining 13 patients within 5 days. Of the stroke cohort, for whom the mRS was available, the mean preCEA mRS was 3.4. One patient in the stroke cohort had a postoperative stroke (0.5%, 1/194). In the total CEA cohort, there were 3 total postoperative strokes (0.6%, 3/465). There was one death in the total cohort (0.2%). The mean operative time was 45 min ± 4 min. CONCLUSIONS: Early CEA for recurrent stroke prevention can be performed safely, at an earlier time frame than current recommendations. Given the safety of early CEA and the risk of recurrent stroke, CEA for stroke is best done early with no additional increase in morbidity or mortality.


Asunto(s)
Estenosis Carotídea , Endarterectomía Carotidea , Ataque Isquémico Transitorio , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Anciano , Anciano de 80 o más Años , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/cirugía , Endarterectomía Carotidea/efectos adversos , Humanos , Ataque Isquémico Transitorio/diagnóstico , Ataque Isquémico Transitorio/etiología , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/etiología , Factores de Tiempo , Resultado del Tratamiento
3.
Nature ; 456(7223): 809-13, 2008 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-18997771

RESUMEN

Angiogenesis does not only depend on endothelial cell invasion and proliferation: it also requires pericyte coverage of vascular sprouts for vessel stabilization. These processes are coordinated by vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) through their cognate receptors on endothelial cells and vascular smooth muscle cells (VSMCs), respectively. PDGF induces neovascularization by priming VSMCs/pericytes to release pro-angiogenic mediators. Although VEGF directly stimulates endothelial cell proliferation and migration, its role in pericyte biology is less clear. Here we define a role for VEGF as an inhibitor of neovascularization on the basis of its capacity to disrupt VSMC function. Specifically, under conditions of PDGF-mediated angiogenesis, VEGF ablates pericyte coverage of nascent vascular sprouts, leading to vessel destabilization. At the molecular level, VEGF-mediated activation of VEGF-R2 suppresses PDGF-Rbeta signalling in VSMCs through the assembly of a previously undescribed receptor complex consisting of PDGF-Rbeta and VEGF-R2. Inhibition of VEGF-R2 not only prevents assembly of this receptor complex but also restores angiogenesis in tissues exposed to both VEGF and PDGF. Finally, genetic deletion of tumour cell VEGF disrupts PDGF-Rbeta/VEGF-R2 complex formation and increases tumour vessel maturation. These findings underscore the importance of VSMCs/pericytes in neovascularization and reveal a dichotomous role for VEGF and VEGF-R2 signalling as both a promoter of endothelial cell function and a negative regulator of VSMCs and vessel maturation.


Asunto(s)
Vasos Sanguíneos/metabolismo , Neovascularización Fisiológica/fisiología , Pericitos/metabolismo , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Inhibidores de la Angiogénesis/farmacología , Animales , Línea Celular , Células Cultivadas , Fibrosarcoma/irrigación sanguínea , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Neovascularización Fisiológica/efectos de los fármacos , Pericitos/efectos de los fármacos , Factor de Crecimiento Derivado de Plaquetas/farmacología , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Receptores de Factores de Crecimiento Endotelial Vascular/metabolismo , Transducción de Señal
4.
Magn Reson Med ; 65(4): 1013-20, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21413065

RESUMEN

Carotid plaque calcification normally appears as a signal void with clinical MR sequences. Here, we describe the use of an adiabatic inversion recovery prepared two-dimensional ultrashort echo time sequence to image and characterize carotid plaque calcification using a clinical 3-T scanner. T(1), T 2*, and free water content were measured for seven carotid samples, and the results were compared with micro-CT imaging. Conventional gradient echo and fast spin echo images were also acquired for comparison. Correlations between T(1), T 2*, free water concentration, and mineral density were performed. There was a close correspondence between inversion recovery prepared two-dimensional ultrashort echo time morphologic and micro-CT appearances. Carotid plaque calcification varied significantly from sample to sample, with T(1) s ranging from 94 ± 19 to 328 ± 21 msec, T 2*s ranging from 0.31 ± 0.12 to 2.15 ± 0.25 msec, and free water concentration ranging from 5.7 ± 2.3% to 16.8 ± 3.4%. There was a significant positive correlation between T(1)(R = 0.709; P < 0.074), T 2* (R = 0.816; P < 0.025), and free water concentration, a negative correlation between T(1) (R = 0.773; P < 0.042), T 2* (R = 0.948; P < 0.001) and CT measured mineral density, and a negative correlation between free water concentration (R = 0.936; P < 0.002) and mineral density.


Asunto(s)
Algoritmos , Calcinosis/patología , Arterias Carótidas/patología , Estenosis Carotídea/patología , Interpretación de Imagen Asistida por Computador/métodos , Angiografía por Resonancia Magnética/métodos , Calcinosis/complicaciones , Estenosis Carotídea/etiología , Humanos , Aumento de la Imagen/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
5.
Ann Vasc Surg ; 24(6): 825.e1-5, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20472384

RESUMEN

High-voltage electrical burns are rare but cause devastating injuries, resulting in potential limb loss and major morbidity and mortality. These injuries are more insidious than flame burns in that the extent of the injury is not obvious at first glance. Damage to underlying muscle, nerve, and vessels may occur, resulting in limb-threatening ischemia and delayed hemorrhage. The management of such injuries remains controversial and can be challenging for the vascular and reconstructive surgeon. We present a case of high-voltage electrical injury to bilateral upper extremities resulting in limb-threatening ischemia, review the literature on the management of such injuries, and propose an algorithm to guide the management of these devastating injuries.


Asunto(s)
Arteriopatías Oclusivas/etiología , Quemaduras por Electricidad/complicaciones , Isquemia/etiología , Trombosis/etiología , Extremidad Superior/irrigación sanguínea , Adulto , Amputación Quirúrgica , Arteriopatías Oclusivas/diagnóstico , Arteriopatías Oclusivas/fisiopatología , Arteriopatías Oclusivas/cirugía , Arterias/lesiones , Arterias/cirugía , Hemodinámica , Humanos , Isquemia/diagnóstico , Isquemia/fisiopatología , Isquemia/cirugía , Ligadura , Masculino , Flujo Sanguíneo Regional , Reoperación , Vena Safena/trasplante , Trasplante de Piel , Trombectomía , Trombosis/diagnóstico , Trombosis/fisiopatología , Trombosis/cirugía , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares
6.
Ann Vasc Surg ; 23(3): 411.e9-15, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-18619776

RESUMEN

Blunt peripheral extremity vascular injuries are much less frequent than those of penetrating injuries, especially in the absence of significant musculoskeletal trauma. We present an unusual case of complete femoral artery and vein avulsion that resulted from a forced hip hyperextension and thigh abduction after slipping when a patient's foot became entrapped in a ladder. The patient presented with an acutely ischemic right lower extremity 8 hr postinjury, which necessitated immediate surgical exploration, temporary intravascular shunting, interposition grafting, and prophylactic fasciotomy. To our knowledge, this is the first such mechanism to be reported resulting in complete transection of both femoral artery and vein. We review the mechanism of injury and management.


Asunto(s)
Arteria Femoral/lesiones , Vena Femoral/lesiones , Isquemia/etiología , Enfermedades Musculoesqueléticas/complicaciones , Heridas no Penetrantes/etiología , Adolescente , Adulto , Anciano , Niño , Preescolar , Fasciotomía , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/cirugía , Vena Femoral/diagnóstico por imagen , Vena Femoral/cirugía , Humanos , Isquemia/diagnóstico por imagen , Isquemia/cirugía , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares , Heridas no Penetrantes/diagnóstico por imagen , Heridas no Penetrantes/cirugía , Adulto Joven
7.
J Transl Med ; 6: 45, 2008 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-18713449

RESUMEN

Critical limb ischemia (CLI) is an advanced form of peripheral artery disease which is responsible for approximately 100,000 amputations per year in the US. Trials to date have reported clinical improvement and reduced need for amputation in CLI patients receiving autologous bone marrow or mobilized peripheral blood stem cells for stimulation of angiogenesis. While such treatments are currently entering Phase III trials, practical and scientific pitfalls will limit widespread implementation if efficacy is proven. Hurdles to be overcome include: a) reduced angiogenic potential of autologous cells in aged patients with cardiovascular risk factors; b) invasiveness/adverse effects of bone marrow extraction and G-CSF mobilization, respectively; and c) need for on-site cellular manipulation. The Endometrial Regenerative Cell (ERC) is a mesenchymal-like stem cell derived from the menstrual blood that is believed to be associated with endometrial angiogenesis. We discuss the possibility of using allogeneic ERCs as an "off the shelf" treatment for CLI based on the following properties: a) High levels of growth factors and matrix metalloprotease production; b) Ability to inhibits inflammatory responses and lack of immunogenicity; and c) Expandability to great quantities without loss of differentiation ability or karyotypic abnormalities.


Asunto(s)
Endometrio/citología , Endometrio/trasplante , Isquemia/terapia , Pierna/irrigación sanguínea , Regeneración , Animales , Femenino , Humanos , Neovascularización Fisiológica , Trasplante Homólogo
8.
J Vasc Surg ; 48(5): 1245-50, 1250.e1-2, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18971036

RESUMEN

OBJECTIVE: The National Kidney Foundation Dialysis Outcomes and Quality Initiative recommends autogenous access for new dialysis procedures. The patient requiring hemodialysis with inadequate superficial arm veins represents a formidable challenge to the surgeon. Our objective is to describe results with an alternative access procedure, the autogenous brachial-brachial artery (ABBA) access in patients with inadequate superficial arm veins. METHODS: One surgeon created 163 new dialysis accesses in 122 patients during 40 consecutive months at a university hospital. There was 97% patient follow-up. All patent but diminutive superficial arm veins as judged by preoperative ultrasound were explored. Arms with inadequate veins at exploration or arms with thrombosed veins on ultrasound received either prosthetic or ABBA procedures. Upper-arm access was often staged, involving a second "superficialization" procedure. This is a retrospective case series based on a comprehensive medical record review. Cox proportional hazards models were used to compare access patency for individual as well as multiple factors suspected or known to influence dialysis access outcomes. Society for Vascular Surgery reporting guidelines were used except where specifically noted and justified otherwise. RESULTS: One hundred thirty-five autogenous and 28 prosthetic dialysis operations were performed. Primary patency for all access procedures at 12, 24, and 36 months was 58%, 50%, and 38%, respectively. Primary assisted patency for all access procedures at 12, 24, and 36 months was 97%, 91%, and 85%, respectively. Secondary patency at 12, 24, and 36 months was 99%, 97%, and 97%, respectively. Finally, functional patency at 12, 24, and 36 months was 71%, 67%, and 44.0%, respectively. Of the 122 patients, 70 patients received either ABBA or prosthetic access. ABBA out-performed prosthetic access in terms of primary patency (hazard ratio for prosthetic vs ABBA: 4.21 (95% confidence interval [CI]: 1.49, 11.91) and functional patency (hazard ratio for prosthetic vs ABBA: 6.27 95% CI: 1.24-31.72) in patients referred early. Functional patency was more likely to be compromised in elderly patients and in patients with hypercoagulable diagnoses. CONCLUSIONS: Autogenous brachial-brachial access for dialysis out-performed prosthetic access with respect to primary and functional patency in patients referred early without differences in overall complications.


Asunto(s)
Brazo/irrigación sanguínea , Derivación Arteriovenosa Quirúrgica , Implantación de Prótesis Vascular , Arteria Braquial/cirugía , Diálisis Renal , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Derivación Arteriovenosa Quirúrgica/efectos adversos , Implantación de Prótesis Vascular/efectos adversos , Arteria Braquial/fisiopatología , Femenino , Oclusión de Injerto Vascular/etiología , Oclusión de Injerto Vascular/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Derivación y Consulta , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Grado de Desobstrucción Vascular , Venas/cirugía
9.
Ann Vasc Surg ; 22(5): 657-62, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18619775

RESUMEN

The National Kidney Foundation Dialysis Outcomes and Quality Initiative (DOQI) recommends autogenous fistulae as the preferred access for new dialysis procedures. Unfortunately, despite superior patency rates compared to prosthetic grafts, even autogenous access durability is often undermined by venous stenosis due to intimal hyperplasia at the outflow vein or by central venous stenosis due to long-standing central venous catheters. Salvage interventions, in the form of endovascular treatments such as percutaneous transluminal angioplasty (PTA) and/or stenting, are increasingly utilized for access salvage and maintenance. The objective of this study was to evaluate the efficacy of endovascular dialysis interventions in the era of DOQI. A retrospective review of a database of endovascular interventions for dialysis access during 36 months at an academic medical center was performed. Both central venous and access outflow lesions were included in the analysis. Kaplan-Meier curves and log-rank analysis were used to assess and compare time-dependent variables. Forty-five patients with dialysis access underwent 72 endovascular interventions for access maintenance. There were 27 central venous and 32 outflow endovascular interventions with 98% follow-up. Primary and assisted primary patency rates for outflow balloon PTA were 50% and 72% at 12 months, respectively. There were 1.1 reinterventions required per index outflow PTA procedure. Postintervention primary patency rates for central venous PTA were 30% and 9% at 6 and 12 months, respectively. Postintervention assisted patency for central venous PTA was 100% at 12 months, requiring 1.8 reinterventions per index PTA. Central venous and venous outflow interventions extended overall access patency by 38.5 and 33 months, respectively (p < 0.0001). Endovascular interventions are the mainstay of treatment for the malfunctioning dialysis access. Despite the need for multiple reinterventions and close surveillance, catheter-based interventions positively contribute to dialysis access durability in accordance with DOQI guidelines.


Asunto(s)
Angioplastia de Balón , Derivación Arteriovenosa Quirúrgica/efectos adversos , Implantación de Prótesis Vascular/efectos adversos , Oclusión de Injerto Vascular/terapia , Evaluación de Procesos y Resultados en Atención de Salud , Diálisis Renal , Grado de Desobstrucción Vascular , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Angioplastia de Balón/instrumentación , Derivación Arteriovenosa Quirúrgica/normas , Implantación de Prótesis Vascular/normas , Oclusión de Injerto Vascular/etiología , Oclusión de Injerto Vascular/fisiopatología , Humanos , Persona de Mediana Edad , Evaluación de Procesos y Resultados en Atención de Salud/normas , Guías de Práctica Clínica como Asunto , Sistema de Registros , Diálisis Renal/normas , Estudios Retrospectivos , Stents , Factores de Tiempo , Resultado del Tratamiento
10.
Ann Vasc Surg ; 22(4): 525-33, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18620111

RESUMEN

We evaluated whether there was a clinical outcome benefit in patients incidentally discovered to have high-grade renal artery stenosis (RAS) and treated with percutaneous transluminal renal angioplasty and stenting (PTRAS) at the time of angiogram for another indicated procedure. A retrospective chart review was performed on all patients undergoing renal arteriography over 4 years at our academic tertiary-care referral center. Review of catheterization reports was used to identify patients diagnosed with high-grade RAS (reduction of > or =70% luminal diameter by arteriogram). Patients treated with PTRAS were identified. Baseline and postprocedure blood pressure (BP, an average of at least three independent measurements), glomerular filtration rate, serum creatinine, and antihypertensive medication regimen were compared for 12 months of follow-up. Over 4 years, 124 patients underwent renal arteriography and 78 (63%) were diagnosed with high-grade RAS. Fifty-eight patients (74% of those with high-grade RAS) received PTRAS. Patients treated with PTRAS had similar baseline characteristics to those with high-grade RAS with no intervention, with the exception of lower diastolic BP (DBP; 74 +/- 11.2 vs. 80 +/- 14.2 mm Hg, p = 0.04) and a higher proportion of hyperlipidemia (78 vs. 55%, p = 0.05). Thirty-eight out of 58 PTRAS patients (66%) received sufficient follow-up to assess outcomes. When baseline and postprocedure variables were compared in PTRAS patients with 12-month follow-up, there was a reduction in systolic BP (SBP, 153 +/- 20.8 vs. 136 +/- 27.2 mm Hg, p = 0.01) and mean arterial pressure (MAP, 103 +/- 11.2 vs. 95 +/- 14 mm Hg, p = 0.04). When these patients were stratified by those with an increase, decrease, or no change in postprocedure antihypertensive medications, significant reductions in SBP, MAP, and DBP were noted only in the patient population that also had an increase in the number of antihypertensive medications. No differences in renal insufficiency were detected. Patients with high-grade RAS incidentally discovered during arteriography performed for extrarenal disease and treated with PTRAS have a modest reduction in BP, which is significant only in those patients with an increased number of antihypertensive medications postprocedure. Caution must be taken in stenting patients with incidental RAS as outcome benefit may be minimal when compared to medical management only.


Asunto(s)
Angioplastia de Balón , Obstrucción de la Arteria Renal/terapia , Stents , Anciano , Presión Sanguínea , Femenino , Tasa de Filtración Glomerular , Humanos , Hallazgos Incidentales , Masculino , Radiografía , Arteria Renal/diagnóstico por imagen , Obstrucción de la Arteria Renal/diagnóstico por imagen , Obstrucción de la Arteria Renal/fisiopatología , Resultado del Tratamiento
11.
Am J Obstet Gynecol ; 197(5): 470.e1-4, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17980178

RESUMEN

Massive hemorrhage from abnormal placentation is a leading cause of postpartum maternal death and hysterectomy after cesarean section. The endovascular surgeon and radiologist are increasingly asked to assist in the management of these complex patients with the placement of bilateral internal iliac artery balloon catheters. We report the case of a 27-year-old woman with placenta percreta with preemptive bilateral internal iliac artery balloons who had iliac artery thrombosis and acute limb ischemia develop 7 hours after cesarean hysterectomy. This is the first report of iliac artery thrombosis in this setting. A review of the vascular and obstetrical literature reveals divergent recommendations for the use of this technique in patients with abnormal placentation. No guidance from rigorous prospective evidence is available and thus we offer recommendations for the cautious use of this modality.


Asunto(s)
Cateterismo , Arteria Ilíaca , Placenta Accreta/terapia , Adulto , Algoritmos , Pérdida de Sangre Quirúrgica , Femenino , Hematócrito , Hematoma , Humanos , Histerectomía , Imagen por Resonancia Magnética , Placenta Accreta/diagnóstico , Hemorragia Posparto/etiología , Embarazo , Trombectomía , Tomografía Computarizada por Rayos X
12.
J Biochem Biophys Methods ; 70(3): 329-33, 2007 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-16962665

RESUMEN

Vascular permeability is a pathologic process in many disease states ranging from metastatic progression of malignancies to ischemia-reperfusion injury. In order to more precisely study tissue, and more specifically cell layer permeability, our goal was to create a fluorescence-based assay which could quantify permeability without radioactivity or electrical impedance measurements. Human aortic endothelial cells were grown in monolayer culture on Costar-Transwell clear polyester membrane 6-well cell culture inserts. After monolayer integrity was confirmed, vascular endothelial growth factor (VEGF(165)) at varying concentrations with a fixed concentration of yellow-green fluorescent 0.04 microm carboxylate-modified FluoSpheres microspheres were placed in the luminal chamber and incubated for 24 h. When stimulated with VEGF(165) at 20, 40, 80, and 100 ng/ml, this assay system was able to detect increases in trans-layer flux of 8.2+/-2.4%, 16.0+/-3.7%, 41.5+/-4.9%, and 58.6+/-10.1% for each concentration, respectively. This represents the first fluorescence-based permeability assay with the sensitivity to detect changes in the permeability of a cell layer to fluid flux independent of protein flux; as well as being simpler and safer than previous radioactive-and impedance-based permeability assays. With the application of this in vitro assay to a variety of pathologic conditions, both the dynamics and physiology relating to cellular permeability can be more fully investigated.


Asunto(s)
Permeabilidad Capilar , Biofisica/métodos , Permeabilidad Capilar/efectos de los fármacos , Permeabilidad Capilar/fisiología , Permeabilidad de la Membrana Celular/efectos de los fármacos , Permeabilidad de la Membrana Celular/fisiología , Células Cultivadas , Células Endoteliales/efectos de los fármacos , Células Endoteliales/fisiología , Colorantes Fluorescentes , Humanos , Microesferas , Modelos Biológicos , Proteínas Recombinantes/farmacología , Factor A de Crecimiento Endotelial Vascular/farmacología
13.
Surgery ; 138(4): 780-7, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16269309

RESUMEN

BACKGROUND: Vascular endothelial growth factor (VEGF) is a potent vascular mitogen that selectively stimulates vascular smooth muscle cell (VSMC) migration through an unknown mechanism while having no effect on VSMC proliferation. It is known that VSMC migration and proliferation are dependent on the second messenger Ca2+ and, in particular, mitogen-stimulated Ca2+ influx. We hypothesized that the selective effect of VEGF on VSMC migration versus proliferation was a result of differential VEGF-stimulated Ca2+ signaling pathways. METHODS: Primary cultured human aortic smooth muscle cells (VSMCs) were grown to subconfluency and assigned to the following experimental groups: no stimulation, stimulation with platelet-derived growth factor-BB (PDGF-BB) (20 ng/mL) as positive control, and stimulation with VEGF165 (40 ng/mL). Total increase in [Ca2+]cyt and intracellular calcium release was quantified with the use of a fura-2 fluorescence assay. Assays for the following receptors VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1) and PDGFR-beta were performed by immunoprecipitation, while PLCgamma1, Akt 1/2, and phospholamban B phosphorylation were assessed with Western immunoblotting. RESULTS: VSMCs stimulated with VEGF165 exhibited no intracellular Ca2+ release, compared with a 75 +/- 30 nmol/L intracellular calcium release after PDGF-BB stimulation, (P < .02) VEGF165-stimulated VSMCs in Ca2+-containing media exhibited 192 +/- 26 nmol/L increase in [Ca2+]cyt, compared with 354 +/- 54 nmol/L increase after PDGF-BB stimulation (P < .02). VEGF165 did not phosphorylate PLCgamma1 after 1, 5, or 10 minutes of treatment. VEGF165 treatment did not result in PI3-K/Akt activation at 1-, 5-, or 10-minute time points. Calmodulin-dependent kinase II (CaMKII) was activated by both VEGF165 and PDGF-BB after 1 and 5 minutes of stimulation. The presence of the receptors VEGFR-1, VEGFR-2, and PDGFR-beta was confirmed in all experimental groups. CONCLUSIONS: VEGF induces extracellular calcium influx but no intracellular calcium release in VSMCs. This lack of intracellular Ca2+ release stems from the inability of VEGF165 to activate the PLCgamma1 cascade and IP3 receptor-mediated Ca2+ release. The lack of PI3-K/Akt activation at these time points indicates a novel extracellular Ca2+ influx pathway sufficient to activate CaMKII. A paradigm relating extracellular Ca2+ influx to CaMKII activation and migration is suggested and may account for the selective effects of VEGF on VSMC migration.


Asunto(s)
Señalización del Calcio , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Aorta/citología , Calcio/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Células Cultivadas , Activación Enzimática/efectos de los fármacos , Líquido Extracelular/metabolismo , Humanos , Inmunoprecipitación , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfolipasa C gamma/metabolismo , Proteínas Proto-Oncogénicas c-akt/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factor A de Crecimiento Endotelial Vascular/farmacología , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
14.
Perspect Vasc Surg Endovasc Ther ; 17(2): 83-93, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16110368

RESUMEN

Although it has been clearly established that in certain groups of patients, such as in patients with symptomatic high-grade carotid stenosis and in selected asymptomatic patients with high-grade stenosis, carotid endarterectomy offers significant protection from stroke compared with medical therapy, the role of carotid stenting in this patients versus carotid endarterectomy is undergoing a rapid evolution. The definitive evidence awaits the results of ongoing prospective, randomized trials such as CREST and others, but it is clear that carotid stenting will increasingly occupy a significant role in the therapy of carotid bifurcation disease. In that context, vascular surgeons, traditionally the experts on the management of this condition, face the specter of other disciplines intervening in its treatment. In addition, if vascular surgeons do not acquire the skills and the expertise necessary to perform carotid stenting, it is self-evident that they run the risk of being spectators rather retaining the mantle of expert in the management of carotid bifurcation disease. As such, it is the duty of vascular surgeons to acquire the skills with which to retain their rightful place in its management and treatment. The purpose of this article is to describe the skills necessary to become competent in the endovascular management of carotid disease, offer some thoughts and strategy by which one can gain experience and develop an armamentarium of skills necessary to perform carotid stenting, and offer a comprehensive array of options of management and treatment to the patient with carotid disease.


Asunto(s)
Angioplastia de Balón , Arterias Carótidas , Competencia Clínica , Stents , Angiografía/normas , Angioplastia de Balón/educación , Arterias Carótidas/diagnóstico por imagen , Endarterectomía Carotidea , Humanos , Radiografía Intervencional
15.
Vasc Endovascular Surg ; 37(3): 213-7, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12799731

RESUMEN

Extracranial internal carotid artery (ICA) mycotic aneurysms are rare entities that may result in significant neurologic morbidity and mortality. Several operative techniques have been described in the literature for the management of this difficult condition. This case report describes a contained ruptured mycotic aneurysm of the extracranial ICA associated with Proteus mirabilis infection successfully treated by an end-to-end spatulated interposition saphenous vein graft.


Asunto(s)
Aneurisma Infectado/cirugía , Arteria Carótida Interna , Infecciones por Proteus/cirugía , Proteus mirabilis , Anciano , Anciano de 80 o más Años , Aneurisma Infectado/diagnóstico por imagen , Aneurisma Infectado/microbiología , Angiografía Cerebral , Humanos , Masculino , Infecciones por Proteus/complicaciones , Vena Safena/trasplante , Procedimientos Quirúrgicos Vasculares
16.
Am J Surg ; 198(6): 881-8, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19969146

RESUMEN

BACKGROUND: The Surgical Care Improvement Project (SCIP) was designed to reduce perioperative complications. We describe our institutional experience in 6 major areas: surgical site infection, venous thromboembolism prevention, use of perioperative beta-blockade, serum glucose level greater than 200 mg/dL, normothermia, and the use of electric razors for hair removal. METHODS: This was a retrospective review of surgical cases. Evidence-based training and standardization of system and process were undertaken. Compliance with SCIP guidelines was determined. RESULTS: Overall SCIP compliance improved from 80% to 94% over a 2-year period. Standardized antibiotic dosing times improved compliance to more than 90%. Appropriate preoperative antibiotic choice improved to 100%. Cessation of antibiotics postoperatively within 24 hours remains a difficult task. Venous thromboembolism prophylaxis has been difficult to achieve because of postoperative bleeding concerns. Administration of beta-blockers has remained one of the most difficult problems to correct because of the multiplicity of avenues by which a patient may arrive to the operating suite. CONCLUSIONS: Achievement of the SCIP goals is a formidable, but achievable, process requiring individual, cultural, systems, and institutional changes to achieve success.


Asunto(s)
Evaluación de Procesos y Resultados en Atención de Salud , Complicaciones Posoperatorias/prevención & control , Procedimientos Quirúrgicos Operativos/normas , Centros Médicos Académicos , Antagonistas Adrenérgicos beta/uso terapéutico , Glucemia/análisis , Temperatura Corporal , California , Humanos , Evaluación de Programas y Proyectos de Salud , Estudios Retrospectivos , Infección de la Herida Quirúrgica/prevención & control , Tromboembolia Venosa/prevención & control
17.
Ann Vasc Surg ; 22(2): 203-9, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18346573

RESUMEN

Venous hypertension due to proximal central venous outflow obstruction coexisting with a functioning arteriovenous fistula in the ipsilateral arm presents with a complex management problem in hemodialysis patients. Ligation of the arteriovenous communication is the simplest procedure to relieve symptoms; however, this sacrifices the patient's hemodialysis access, which may be the only available access in that patient. Surgical bypass of the occlusion is a potential option as it obviates the symptoms of venous hypertension while preserving dialysis access. Our objective was to evaluate our experience and outcome with dialysis patients undergoing surgical bypass for symptomatic central venous obstruction and dialysis access salvage. There were three hemodialysis patients with severe venous hypertension secondary to subclavian vein obstruction who had functioning ipsilateral arteriovenous fistulae. All underwent cephalic vein (n = 2) or axillary vein (n = 1) to internal jugular vein bypass of the obstructed subclavian segment via an 8-mm polytetrafluoroethylene bridge graft. All patients had unsuccessful percutaneous transluminal angioplasty (PTA) attempts prior to surgical bypass. In two patients, a wire could not be passed through the occlusion; in the third, PTA was only transiently successful despite four repeated procedures. All patients had complete resolution of symptoms without operative mortality. The bypass grafts remained patent, allowing the arteriovenous fistulae to provide functional access for the entire duration of follow-up after surgery (3-8 months). Surgical bypass of a central vein obstruction relieves the symptoms of venous hypertension and prolongs the use of the existing hemodialysis access. This surgical option should be well recognized within the dialysis community.


Asunto(s)
Derivación Arteriovenosa Quirúrgica/efectos adversos , Implantación de Prótesis Vascular , Diálisis Renal , Vena Subclavia/patología , Adulto , Anciano , Brazo/irrigación sanguínea , Constricción Patológica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Vasculares/métodos
18.
Methods Enzymol ; 444: 159-74, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19007664

RESUMEN

Ischemia and ischemia-reperfusion (I/R) events are distinct but interrelated processes etiologic to the most prevalent human diseases. A delicate balance exists whereby ischemic injury can result in beneficial angiogenesis or in detrimental reperfusion injury overwhelming the organism. Here, we describe in vivo models of ischemia and ischemia-reperfusion injury with emphasis on murine hindlimb ischemia models. We also provide a brief introduction to murine myocardial ischemia experiments. Each model is described in the context of human disease. Emphasis is made on the strengths and weaknesses of the available techniques, particularly as it relates to data analysis, interpretation, and translational relevance.


Asunto(s)
Modelos Animales de Enfermedad , Neovascularización Patológica , Daño por Reperfusión , Animales , Miembro Posterior/irrigación sanguínea , Miembro Posterior/lesiones , Humanos , Ratones , Infarto del Miocardio
19.
Vascular ; 16(1): 25-30, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18258159

RESUMEN

The purposes of this study were to (1) investigate compression levels beneath an inelastic legging equipped with a new pressure-adjustment system, (2) compare the inelastic compression levels with those provided by a well-known elastic stocking, and (3) evaluate each support's gradient compression production. Eighteen subjects without venous reflux and 12 patients with previously documented venous reflux received elastic and inelastic compression supports sized for the individual. Skin surface pressures under the elastic (Sigvaris 500, 30-40 mm Hg range, Sigvaris, Inc., Peachtree City, GA) and inelastic (CircAid C3 with Built-in-Pressure System [BPS], CircAid Medical Products, San Diego, CA) supports were measured using a calibrated Tekscan I-Scan device (Tekscan, Inc., Boston, MA). The elastic stocking produced significantly lower skin surface pressures than the inelastic legging. Mean pressures (+/- standard error) beneath the elastic stocking were 26 +/- 2 and 23 +/- 1 mm Hg at the ankle and below-knee regions, respectively. Mean pressures (+/- standard error) beneath the inelastic legging with the BPS were 50 +/- 3 and 38 +/- 2 mm Hg at the ankle and below-knee regions, respectively. Importantly, our study indicates that only the inelastic legging with the BPS produces significant ankle to knee gradient compression (p = .001).


Asunto(s)
Medias de Compresión , Insuficiencia Venosa/terapia , Anciano , Tobillo/fisiología , Elasticidad , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Presión , Fenómenos Fisiológicos de la Piel
20.
Arch Surg ; 143(8): 736-42; discussion 742, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18711032

RESUMEN

BACKGROUND: Carotid angioplasty and stenting (CAS) is now a viable alternative to carotid endarterectomy (CEA) in patients considered to be high-risk candidates for surgery, despite recent reports of increased adverse periprocedural outcomes in elderly patients. We sought to evaluate our single-institution experience and the 30-day perioperative outcomes of CEA in patients 75 years or older, who are traditionally considered high-risk surgical candidates and are recommended for CAS. DESIGN: Retrospective medical record review. SETTING: Academic tertiary care center. PATIENTS: All patients 75 years or older undergoing CEA during a 16-year period. MAIN OUTCOME MEASURES: Primary outcome of 30-day perioperative stroke, death, or myocardial infarction (MI) and a composite outcome of stroke, death, or MI. Secondary outcomes of all perioperative complications were exclusive of primary outcomes. RESULTS: One hundred seventeen CEAs were performed in 110 patients 75 years or older. Significant medical comorbidities were well represented among the group. Among the patients, 50.4% were symptomatic, 60.7% had greater than 90% carotid stenosis, and 44.4% had contralateral disease. Primary outcome for any stroke, death, or MI was 1.7%, 0.9%, or 3.4%, respectively, with a composite event rate of any stroke or death of 2.6%. One or more secondary outcomes were experienced by 26.5% of patients. CONCLUSIONS: Carotid endarterectomy in elderly patients with significant comorbidities, traditionally thought to be a high-risk undertaking, is a safe procedure with periprocedural risks of stroke, death, and MI equivalent to those of younger patients. In light of the increased stroke risk in elderly patients with CAS, CEA remains the criterion standard for prevention of stroke in this patient population.


Asunto(s)
Enfermedades de las Arterias Carótidas/cirugía , Endarterectomía Carotidea/normas , Anciano , Anciano de 80 o más Años , Enfermedades de las Arterias Carótidas/epidemiología , Comorbilidad , Femenino , Humanos , Masculino , Estudios Retrospectivos
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