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1.
J Pers Soc Psychol ; 117(3): 605-620, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30667256

RESUMEN

People working toward individual goals often find themselves surrounded by others who are pursuing similar goals, such as at school, in fitness classes, and through goal-oriented network devices like Fitbit. This research explores when these individual goal pursuits can turn into competitions, why it happens, and the downstream consequences of this pseudocompetition on goal pursuers. We found that people were more likely to treat their goal pursuit as a competition when they were near the end (vs. at the beginning) of their individual goal and, thus, prioritized relative positional gain (i.e., performing better than others sharing similar pursuits) over making objective progress on their own goal, sabotaging others when they had the opportunity to do so (Studies 1-3B). Further, we provided evidence that certainty of goal attainment at a high (vs. low) level of progress drove this shift in focus, leading to such sabotage behaviors (Studies 3A and 3B). Ironically, success in gaining an upper hand against others in these pseudocompetitions led individuals to subsequently reduce their effort in their own pursuits (Studies 1-5). Six experiments captured a variety of competitive behaviors across different goal domains (e.g., selecting games that diminished others' prospects, selecting difficult questions for fellow students). (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Asunto(s)
Conducta Competitiva , Objetivos , Relaciones Interpersonales , Autocontrol , Percepción Social , Adulto , Femenino , Humanos , Masculino , Adulto Joven
2.
J Vasc Surg ; 47(4): 708-713, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18381130

RESUMEN

OBJECTIVE: Iliac artery aneurysms are rare but associated with significant morbidity and mortality when ruptured. This study compares recent open and endovascular repairs of iliac aneurysms at a single institution. METHODS: Patients were identified and charts reviewed using ICD-9 and CPT codes for iliac artery aneurysm and open or endovascular repair performed between January 2000 and January 2006. Baseline characteristics, procedure-related variables, and follow-up data were retrospectively reviewed. RESULTS: A total of 71 patients were treated with isolated iliac artery aneurysms. There were 19 open and 52 endovascular repairs. Seven presented with acute ruptures and were treated by open (4) or endovascular (3) repair. Preoperative comorbidities were similar between the two groups. Major perioperative (30 day) complications included three deaths in the open group from cardiovascular complications, all after ruptured aneurysm repair, and one death in the endovascular group (after rupture; one additional perioperative death occurred after 30 days due to colonic infarction) (P = NS). Postoperative complications were less frequent in the endovascular group, although this did not reach statistical significance. The mortality was 50% in the open group and 33% in the endovascular group for patients presenting with a ruptured aneurysm (P = NS). Transfusion requirement was significantly higher in the open group (47%) than in the endovascular group (6%) (P = .03). The mean follow-up was 20 +/- 5 months in the open group and 17 +/- 2 months in the endovascular group (P = NS). Long-term complications included two limb thromboses following repair with a bifurcated stent graft that were treated with thrombolysis plus stenting or a fem-fem bypass. Three endoleaks were identified on postop CT scans, all of which were successfully managed with endovascular techniques. There were no postoperative ruptures or aneurysm-related death. The mean postoperative length of stay was 5.2 +/- 2.3 days (open) and 1.3 +/- 1.0 days (endovascular) (P = .04). CONCLUSIONS: This is the first large, case control study comparing open vs endovascular repair of isolated iliac artery aneurysms. Endovascular repair of iliac artery aneurysms is safe and results in decreased length of stay, lower requirement for perioperative blood transfusion, and similar intermediate term outcomes as open repair.


Asunto(s)
Disección Aórtica/cirugía , Prótesis Vascular , Aneurisma Ilíaco/cirugía , Stents , Anciano , Disección Aórtica/mortalidad , Aneurisma Roto/cirugía , Transfusión Sanguínea , Femenino , Humanos , Aneurisma Ilíaco/mortalidad , Tiempo de Internación , Masculino , Complicaciones Posoperatorias , Estudios Retrospectivos , Procedimientos Quirúrgicos Vasculares/métodos
3.
J Vasc Surg ; 47(3): 599-607, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18295111

RESUMEN

PURPOSE: The vascular mediator, nitric oxide regulates vascular smooth muscle cell proliferation and can react with superoxide to form peroxynitrite, a highly reactive free radical. The intracellular mechanisms by which nitric oxide and peroxynitrite inhibit smooth muscle cell growth remain undefined, as is the potential role of peroxynitrite formation in the antiproliferative effects of nitric oxide. We sought to define the intracellular effects and signaling mechanisms of nitric oxide and peroxynitrite in smooth muscle cells. METHODS: Cultured rat aortic smooth muscle cells were treated with exogenous nitric oxide or peroxynitrite and inhibitors of nitric oxide and redox signaling pathways. Cell growth, DNA synthesis, apoptosis, cyclic guanosine 3'-5' monophosphate (cGMP) levels, poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) activity, and cytotoxicity were assayed. Peroxynitrite formation was determined by nitrotyrosine immunoblotting. Vasoreactivity was assessed in isolated rat aortic rings after treatment with nitric oxide/peroxynitrite and redox agents. RESULTS: Both exogenous nitric oxide and peroxynitrite decreased cell growth and DNA synthesis of cultured rat aortic smooth muscle cells, but peroxynitrite-induced growth arrest was irreversible and associated with apoptosis and cytotoxicity. Inhibition of guanylate cyclase, PARP activity, mitogen-activated protein kinase, or bypass of ornithine decarboxylase did not reverse growth arrest by nitric oxide. The antioxidants N-acetylcysteine, ascorbate, and glutathione selectively reversed growth inhibition by nitric oxide but not by peroxynitrite. Antioxidants did not impair nitric oxide-induced cGMP generation in smooth muscle cells or nitric oxide-induced vasodilatation of isolated aortic rings. Nitric oxide treatment did not result in peroxynitrite formation and augmentation of superoxide levels did not induce peroxynitrite-like effects. Peroxynitrite-induced cytotoxicity and apoptosis were not reversed by antioxidants or PARP inhibition, because peroxynitrite activated PARP in J774 macrophages but failed to activate PARP in smooth muscle cells. CONCLUSIONS: Exogenous nitric oxide induces reversible cytostasis in smooth muscle cells by a redox-sensitive mechanism independent of peroxynitrite formation and distinct from the nitric oxide vasodilating mechanism. Peroxynitrite does not activate PARP selectively in smooth muscle cells and induces redox-independent smooth muscle cell cytotoxicity and apoptosis. Thus, the antiproliferative effects of nitric oxide and peroxynitrite on smooth muscle cells use divergent intracellular pathways with distinct redox sensitivities. These findings are relevant to the pathogenesis of vascular disease and the potential application of nitric oxide-based therapy for vascular disease. CLINICAL RELEVANCE: Vascular smooth muscle cell proliferation is an important component of atherosclerosis, vein graft failure, and arterial restenosis, and is known to be regulated by the vascular signaling molecule nitric oxide. Nitric oxide can combine with the free radical superoxide to form the unstable metabolite peroxynitrite, which has been detected in human vascular lesions. This study examines the role of peroxynitrite in mediating the antiproliferative effects of nitric oxide. We identify important differences in the effects and intracellular mechanisms of nitric oxide and peroxynitrite in regulating vascular smooth muscle cell proliferation and programmed cell death. Defining the differential effects of these free radicals in vascular cells is important to our understanding of the pathogenesis of vascular disease and the development of novel therapy aimed at treating proliferative vascular lesions.


Asunto(s)
Proliferación Celular , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Óxido Nítrico/metabolismo , Ácido Peroxinitroso/metabolismo , Poli(ADP-Ribosa) Polimerasas/metabolismo , Transducción de Señal , Animales , Antioxidantes/farmacología , Apoptosis , Proliferación Celular/efectos de los fármacos , Supervivencia Celular , Células Cultivadas , GMP Cíclico/metabolismo , Replicación del ADN , Relación Dosis-Respuesta a Droga , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/enzimología , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/enzimología , Miocitos del Músculo Liso/patología , Donantes de Óxido Nítrico/farmacología , Oxidación-Reducción , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Ratas , Transducción de Señal/efectos de los fármacos , Superóxidos/metabolismo , Factores de Tiempo , Tirosina/análogos & derivados , Tirosina/metabolismo , Vasodilatación
4.
J Vasc Surg ; 45(5): 875-80, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17466784

RESUMEN

PURPOSE: Current evaluations of carotid artery angioplasty and stenting (CAS) have suggested equivalency compared with carotid endarterectomy (CEA). However, the incidence of stroke and death with CAS may be higher in elderly patients. We assessed the anatomic characteristics of patients undergoing CAS and compared them based on age older or younger than 80 years. The impact of age on the incidence of postoperative complications was also determined. METHODS: From February 2003 to August 2005, 135 CAS procedures were performed in 133 patients. Digital subtraction angiograms for each patient were evaluated by two independent observers blinded to patient identifiers. Anatomic characteristics that impact the performance of CAS were assessed as either favorable or unfavorable. These included aortic arch elongation, arch calcification, arch vessel origin stenosis, common and internal carotid artery tortuosity, and treated lesion stenosis, calcification, and length. Postoperative events were defined as myocardial infarction, stroke, and death. Fisher's exact test and chi(2) tests were used to determine statistical significance (P < .05). RESULTS: Of the 133 patients treated, 87 (65%) were men and 46 (35%) were women; and 37 (28%) were >or=80 years of age. The cohort >or=80 years old had an increased incidence of unfavorable arch elongation (P = .008), arch calcification (P = .003), common carotid or innominate artery origin stenosis (P = .006), common carotid artery tortuosity (P = .0009), internal carotid artery tortuosity (P = .019), and treated lesion stenosis (P = .007). No significant difference was found for treated lesion calcification or length. Perioperative cerebral vascular accidents occurred in four patients (3.0%, 3 with no residual deficit, 1 with residual deficit), myocardial infarction in three (2.2%), and one patient (0.8%) died secondary to a hemorrhagic stroke. The combined stroke, myocardial infarction, and death rate for the entire population was 3.7%. The rate was significantly increased in patients aged >or=80 years old (10.8%) compared with those aged <80 years old (1%, P = .012). CONCLUSIONS: Elderly patients, defined as those aged >80 years, have a higher incidence of anatomy that increases the technical difficulty of performing CAS. This increase in unfavorable anatomy may be associated with complications during CAS. Although the small number of perioperative events does not allow for determination of a direct relationship with specific anatomic characteristics, the presence of unfavorable anatomy does warrant serious consideration during evaluation for CAS in elderly patients.


Asunto(s)
Angioplastia de Balón , Arteria Carótida Interna , Estenosis Carotídea/terapia , Stents , Factores de Edad , Anciano , Anciano de 80 o más Años , Angiografía de Substracción Digital , Arteria Carótida Interna/anatomía & histología , Femenino , Humanos , Masculino , Estudios Prospectivos
6.
Am Surg ; 72(8): 694-8; discussion 698-9, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16913312

RESUMEN

Performance of carotid endarterectomy (CEA) may be associated with an increased risk in patients with significant comorbid medical conditions, neck irradiation, or previous CEA. This study compared the results of CEA with carotid angioplasty and stenting (CAS) in high-risk patients treated for carotid stenosis. Five hundred forty-five patients who underwent CEA and 148 patients who underwent CAS were evaluated. For patients undergoing CEA, general anesthesia was used in 91 per cent, electroencephalographic monitoring was used in 63 per cent, and shunting was performed in 19.8 per cent. Cerebral protection devices were used in 145/148 of CAS cases, and self-expanding stents were used in all cases. Evaluated end points included major cardiovascular events, and a composite of death, stroke, or myocardial infarction for the duration of the follow-up. Mean follow-up was 18 months for CAS and 23 months for CEA. Significant differences were present in patient age (CAS, 75 +/- 11.0 years vs CEA, 71 +/- 9 years, P = 0.012), however, there were no significant differences (P = NS) in gender or smoking history. The mean modified Goldman Score was significantly higher for CAS (21.1 +/- 14.8 [95% confidence interval = 18, 24]) than for CEA (6.3 +/- 6.8 [95% confidence interval = 5.7, 6.9]; P = 0.0001) patients. The incidence of periprocedural complications did not vary significantly between patients treated with CAS (CVA, 1.4%; myocardial infarction [MI], 1.4%; death, 0.7%; CVA/MI/death, 3.4%) compared with CEA (CVA, 1.8%; MI, 1.1%; death, 0.4%; CVA/MI/death, 4.0%). CAS is equivalent to CEA in safety and efficacy, even when performed in patients who may be at increased surgical risk.


Asunto(s)
Angioplastia de Balón/métodos , Implantación de Prótesis Vascular/instrumentación , Estenosis Carotídea/terapia , Enfermedad Coronaria/complicaciones , Stents , Factores de Edad , Anciano , Anciano de 80 o más Años , Angiografía , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico , Intervalos de Confianza , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Ultrasonografía Doppler en Color
7.
Ann Surg ; 244(3): 343-52, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16926560

RESUMEN

OBJECTIVES: Surgical simulation has been shown to enhance the training of general surgery residents. Since catheter-based techniques have become an important part of the vascular surgeon's armamentarium, we explored whether simulation might impact the acquisition of catheter skills by surgical residents. METHODS: Twenty general surgery residents received didactic training in the techniques of catheter intervention. Residents were then randomized with 10 receiving additional training with the Procedicus, computer-based, haptic simulator. All 20 residents then participated in 2 consecutive mentored catheter-based interventions for lower extremity occlusive disease in an OR/angiography suite. Resident performance was graded by attending surgeons blinded to the resident's training status, using 18 procedural steps as well as a global rating scale. RESULTS: There were no differences between the 2 resident groups with regard to demographics or scores on a visuospatial test administered at study outset. Overall, residents exposed to simulation scored higher than controls during the first angio/OR intervention: procedural steps (simulation/control) (50 +/- 6 vs. 33 +/- 9, P = 0.0015); global rating scale (30 +/- 7 vs. 19 +/- 5, P = 0.0052). The advantage provided by simulator training persisted with the second intervention (53 +/- 6 vs. 36 +/- 7, P = 0.0006); global rating scale (33 +/- 6 vs. 21 +/- 6, P = 0.0015). Moreover, simulation training, particularly for the second intervention, led to enhancement in almost all of the individual measures of performance. CONCLUSION: Simulation is a valid tool for instructing surgical residents and fellows in basic endovascular techniques and should be incorporated into surgical training programs. Moreover, simulators may also benefit the large number of vascular surgeons who seek retraining in catheter-based intervention.


Asunto(s)
Arteriopatías Oclusivas/terapia , Cateterismo Periférico/normas , Simulación por Computador , Internado y Residencia/normas , Procedimientos Quirúrgicos Vasculares/educación , Angiografía , Arteriopatías Oclusivas/diagnóstico , Humanos , Arteria Ilíaca , Encuestas y Cuestionarios , Procedimientos Quirúrgicos Vasculares/métodos
8.
J Vasc Surg ; 43(5): 946-52; discussion 952, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16678688

RESUMEN

BACKGROUND: Interruption of antegrade cerebral perfusion results in transient neurologic intolerance in some patients undergoing carotid angioplasty and stenting (CAS). This study sought to evaluate factors that contributed to the development of cerebral ischemia during PercuSurge balloon occlusion and techniques used to allow successful completion of the CAS procedure. METHODS: The PercuSurge occlusion balloon was used in 43 of 165 patients treated with CAS for high-grade stenosis (mean stenosis, 90%). All 43 patients were at increased risk for endarterectomy (7 restenosis, 3 irradiation, 3 contralateral occlusion, and 30 Goldman class II-III); 20% were symptomatic. Symptoms of cerebral hypoperfusion during temporary occlusion of the internal carotid artery occurred in 10 of 43 and included dysarthria (7/10), agitation (6/10), decreased level of consciousness (5/10), and focal hemispheric deficit (3/10). An incomplete circle of Willis or contralateral carotid artery occlusion, or both, was present in 8 of 10 patients. Symptoms resulting from PercuSurge balloon occlusion were managed by balloon deflation with or without evacuation of blood from the internal carotid artery using the Export catheter. All symptoms resolved completely without deficit after deflation of the occlusion balloon. RESULTS: The development of neurologic symptoms after initial PercuSurge balloon inflation and occluded internal carotid artery flow was associated with a decrease in the mean Glasgow Coma Scale (GCS) from 15 to 10 (range, 9 to 14); the GCS returned to normal after occlusion balloon deflation and remained normal during subsequent reinflation. The mean time to spontaneous recovery of full neurologic function was 8 minutes (range, 4 to 15 minutes). No thrombotic or embolic events were present on cerebral angiography or computed tomography scan. Balloon reinflation was performed after a mean reperfusion interval of 10 minutes after full neurologic recovery (range, 4 to 20 minutes). The mean subsequent procedure duration was 11.9 minutes (range, 6 to 21 minutes). No recurrence of neurologic symptoms occurred when the occlusion balloon was reinflated. All 10 patients underwent successful CAS without occlusion, dissection, cerebrovascular accident, or death. CONCLUSION: Several factors may contribute to the development of neurologic intolerance during CAS with balloon occlusion. Elucidation of the protective cellular mechanisms that invoke ischemic tolerance after the initial transient ischemic event may enable CAS with embolic protection in patients who cannot tolerate initial interruption of antegrade cerebral perfusion.


Asunto(s)
Angioplastia de Balón/instrumentación , Isquemia Encefálica/etiología , Arteria Carótida Interna , Estenosis Carotídea/terapia , Cateterismo/instrumentación , Stents , Anciano , Anciano de 80 o más Años , Angioplastia de Balón/efectos adversos , Isquemia Encefálica/epidemiología , Arteria Carótida Interna/diagnóstico por imagen , Estenosis Carotídea/diagnóstico por imagen , Cateterismo/efectos adversos , Angiografía Cerebral , Endarterectomía Carotidea , Femenino , Escala de Coma de Glasgow , Humanos , Incidencia , Complicaciones Intraoperatorias/epidemiología , Complicaciones Intraoperatorias/etiología , Masculino , Examen Neurológico , Tomografía Computarizada por Rayos X
9.
Vasc Endovascular Surg ; 40(3): 165-75, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16703204

RESUMEN

Stroke is the third most common cause of death in the United States. There are approximately 700,000 strokes/year; 80% are ischemic, and 20-30% of ischemic strokes are secondary to carotid disease. Carotid stenosis is traditionally treated by carotid endarterectomy (CEA). Multicenter, randomized, controlled trials have shown that surgery significantly reduces the risk of ipsilateral stroke in patients with severe symptomatic and asymptomatic carotid stenosis. Endovascular techniques for treating carotid stenosis have been developed over recent years. Carotid angioplasty and stenting (CAS) with cerebral protection has become an alternative to CEA for high-surgical-risk patients and the procedure of choice for stenoses inaccessible by surgery. In this review we summarize the existing data regarding the traditional state of management of extracranial carotid artery stenosis and compare these data to a critical analysis of the recent results of CAS.


Asunto(s)
Angioplastia/métodos , Estenosis Carotídea/cirugía , Endarterectomía Carotidea/métodos , Stents , Accidente Cerebrovascular/prevención & control , Estenosis Carotídea/diagnóstico , Humanos , Accidente Cerebrovascular/etiología
10.
J Vasc Surg ; 43(4): 714-20, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16616226

RESUMEN

INTRODUCTION: Systemic hypotension has been observed for up to 36 hours in response to stimulation of the carotid baroreceptor by carotid angioplasty and stenting (CAS). The aim of this study was to identify risk factors and cardiac outcomes for postprocedural hypotension requiring vasopressor support after CAS. METHODS: Between 2003 and 2005, 143 patients (87 men; mean age, 75 years) with high-grade carotid artery stenosis (mean, 87.3%) were treated with CAS and prospectively entered into a vascular registry. Data were retrospectively analyzed to determine factors predictive of hypotension requiring vasopressor support after CAS. Atropine and appropriate intravenous crystalloid solution were administered during CAS. For the first 30 patients, atropine was only used for symptomatic patients but then became routine and was used for all patients with primary carotid stenosis. Hypotension (systolic blood pressure <90 mm Hg or a mean arterial blood pressure <50 mm Hg) unresponsive to conservative measures was treated with vasopressors (phenylephrine or norepinephrine). Patients were stratified into three groups based on hypotension requiring vasopressors: (1) no vasopressors, (2) vasopressors for < or = 24 hours (short duration), and (3) vasopressors for >24 hours (prolonged duration). Risk factors for hypotension requiring vasopressors were analyzed by univariate and multivariate logistic regression analysis. RESULTS: Postprocedural hypotension requiring vasopressor treatment was seen in 16 (11%) of 143 of patients, with 6 (4%) requiring vasopressor support for >24 hours. Mean duration of vasopressor administration for all patients was 17 +/- 10 hours (range, 6 to 36 hours). By univariate analysis, a history of a previous myocardial infarction (P = .02) or use of the PercuSurge occlusion balloon (P = .05) were both associated with increased incidence of short duration (80 years old (P = .02) were associated with prolonged (>24 hours) vasopressor requirement. On multivariate analysis adjusted for age and sex, a history of myocardial infarction (odds ratio [OR], 4.1; 95% confidence interval [CI], 1.0 to 16.4; P = .05) remained an independent predictor of short-duration vasopressors. On multivariate analysis, female sex (OR, 10.9; 95% CI, 1.2 to 100.4; P = .04) and age >80 years old (OR, 13.8, 95% CI, 1.5 to 127.2; P = .02) remained independent predictors of prolonged vasopressor use. The incidence of periprocedural myocardial infarctions, arrhythmias, or congestive heart failure did not differ between those patients who did not receive vasopressors (5/127) and those who received vasopressors for a short (< or = 24 hours) duration (1/10, P = NS) or prolonged (>24 hours) duration (0/6, P = NS). CONCLUSION: Prolonged hypotension requiring vasopressor support occurs in a minority of patients after CAS, with higher incidences in older women. In contrast, hypotension requiring a more limited duration of vasopressor use occurs more commonly in patients who had a prior myocardial infarction, independent of age or sex. In this cohort of patients, vasopressors required for hypotension were not associated with an increased incidence of periprocedural cardiac complications. Despite the increased incidence of prolonged hypotension in older women, this study demonstrates that CAS can be performed without an increase in cardiac morbidity in older women.


Asunto(s)
Angioplastia de Balón/efectos adversos , Estenosis Carotídea/terapia , Hipotensión/tratamiento farmacológico , Stents , Vasoconstrictores/administración & dosificación , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Angioplastia de Balón/métodos , Determinación de la Presión Sanguínea , Estenosis Carotídea/diagnóstico por imagen , Estudios de Cohortes , Intervalos de Confianza , Quimioterapia Combinada , Femenino , Hemodinámica/efectos de los fármacos , Humanos , Hipotensión/etiología , Modelos Logísticos , Masculino , Monitoreo Fisiológico/métodos , Oportunidad Relativa , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/tratamiento farmacológico , Pronóstico , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Tasa de Supervivencia , Resultado del Tratamiento , Ultrasonografía Doppler
11.
J Vasc Surg ; 43(2): 388-92, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16476620

RESUMEN

A 65-year-old woman was evaluated for acute right lower-extremity ischemia secondary to embolization from atrial fibrillation and subtherapeutic anticoagulation. Her symptoms quickly evolved in a dynamic fashion to involve multiple vascular beds, including a transient ischemic attack, abdominal pain secondary to mesenteric ischemia, and contralateral lower-extremity ischemia. Synchronous emboli were treated by using mechanical and pharmacologic thrombolysis via an endovascular approach under local anesthesia. This intervention allows prompt evaluation of multiple vascular beds with good short-term outcomes and minimal morbidity.


Asunto(s)
Angioplastia de Balón , Fibrilación Atrial/complicaciones , Embolia/terapia , Fibrinolíticos/uso terapéutico , Isquemia/etiología , Extremidad Inferior/irrigación sanguínea , Oclusión Vascular Mesentérica/etiología , Trombectomía , Activador de Plasminógeno de Tipo Uroquinasa/uso terapéutico , Dolor Abdominal/etiología , Anciano , Anticoagulantes/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Terapia Combinada , Embolia/complicaciones , Embolia/diagnóstico por imagen , Embolia/tratamiento farmacológico , Embolia/etiología , Embolia/cirugía , Femenino , Arteria Femoral/diagnóstico por imagen , Humanos , Isquemia/diagnóstico por imagen , Isquemia/terapia , Ataque Isquémico Transitorio/etiología , Arterias Mesentéricas/diagnóstico por imagen , Oclusión Vascular Mesentérica/complicaciones , Oclusión Vascular Mesentérica/diagnóstico por imagen , Oclusión Vascular Mesentérica/terapia , Arteria Poplítea/diagnóstico por imagen , Radiografía , Resultado del Tratamiento
12.
J Vasc Surg ; 43(1): 109-16, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16414397

RESUMEN

OBJECTIVE: This study used a canine model of abdominal aortic aneurysms (AAAs) to compare intra-aneurysmal pressure and thrombus formation after exclusion with Dacron and expanded polytetrafluoroethylene (ePTFE) stent-grafts. METHODS: Prosthetic AAAs with implanted strain-gauge pressure transducers were treated by stent-graft exclusion using Food and Drug Administration-approved devices in 10 mongrel dogs: five Dacron (AneuRx) and five ePTFE (original Excluder). Intra-aneurysmal pressure was measured over 4 weeks after AAA exclusion and indexed to the systemic pressure, represented as a percentage of a simultaneously obtained systemic pressure (value = 1.0). Magnetic resonance imaging (MRI) of the intra-aneurysmal thrombus was performed at 1, 2, and 4 weeks after exclusion and expressed as a signal-to-noise ratio (S:N) to control for background signal intensity. Comparisons of pressures and S:N between the two stent-grafts was analyzed with the Student's t test. Intra-aneurysmal thrombus was characterized histologically. RESULTS: In animals excluded with both Dacron and ePTFE stent-grafts, the intra-aneurysmal pressure was nonpulsatile and reduced to <30% of systemic pressure. Significantly greater pressure transmission was observed after AAA exclusion using ePTFE compared with Dacron stent grafts (systolic pressure: ePTFE, 0.28 +/- 0.12 vs Dacron, 0.11 +/- 0.02, P < .001; mean pressure: ePTFE, 0.16 +/- 0.08 vs Dacron, 0.06 +/- 0.02, P < .001). MRI confirmed the absence of perfusion in all aneurysms. The T1-weighted signal intensity remained persistently elevated (S:N at 1 week, 2.7 +/- 0.4 vs 2 weeks, 4.0 +/- 0.2 vs 4 weeks, 5.4 +/- 1.3) in ePTFE-treated intra-aneurysmal thrombus, suggesting an absence of thrombus organization. In contrast, progressive evolution of T1 signal intensity in aneurysms excluded by Dacron stent-grafts was consistent with maturation from intact red blood cells (S:N at 1 week, 3.3 +/- 0.4) to methemoglobin (S:N at 2 weeks, 6.1 +/- 0.8), and then hemosiderin and ferritin (S:N at 4 weeks, 2.4 +/- 0.5). Histologically, ePTFE-excluded aneurysms contained poorly organized thrombus with red blood cell fragments and haphazardly arranged fibrin deposition indicative of active remodeling and continued influx of transudated serum. In aneurysms excluded by Dacron stent-grafts, dense, mature collagenous connective tissue and organized fibrin were present, indicative of greater thrombus organization. CONCLUSIONS: Stent-graft treatment reduces intra-aneurysmal pressure to <30% of systemic pressure when no endoleak is present; however, significantly greater pressure is present in aneurysms treated with porous ePTFE stent-grafts than Dacron grafts. Histologic and MRI imaging analysis suggest that active transudation of serous blood components may be contributing to this increased intra-aneurysmal pressure.


Asunto(s)
Aneurisma de la Aorta Abdominal/fisiopatología , Aneurisma de la Aorta Abdominal/cirugía , Prótesis Vascular , Modelos Animales de Enfermedad , Tereftalatos Polietilenos , Politetrafluoroetileno , Stents , Animales , Aneurisma de la Aorta Abdominal/patología , Perros , Diseño de Equipo , Transductores de Presión , Insuficiencia del Tratamiento
13.
Rev Recent Clin Trials ; 1(3): 293-301, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18473981

RESUMEN

Stroke is the third most common cause of death in the United States. There are approximately 700,000 strokes/year, eighty percent are ischemic, and 20-30% of ischemic strokes are secondary to carotid disease. Carotid stenosis is traditionally treated by carotid endarterectomy (CEA). Multicenter randomized controlled trials have shown that surgery significantly reduces the risk of ipsilateral stroke in patients with severe symptomatic and asymptomatic carotid stenosis. Endovascular techniques for treating carotid stenosis have been developed over recent years. Carotid angioplasty and stenting (CAS) with cerebral protection has become an alternative to CEA for high-surgical-risk patients and the procedure of choice for stenoses inaccessible by surgery. In this review we summarize the existing data regarding the traditional state of management of extracranial carotid artery stenosis, and compare these data to a critical analysis of the recent results of CAS.


Asunto(s)
Estenosis Carotídea/terapia , Endarterectomía Carotidea , Arteria Carótida Interna , Estenosis Carotídea/complicaciones , Estenosis Carotídea/cirugía , Cateterismo , Endarterectomía Carotidea/efectos adversos , Filtración , Humanos , Angiografía por Resonancia Magnética , Ensayos Clínicos Controlados Aleatorios como Asunto , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Ultrasonografía Doppler Dúplex
14.
Vasc Endovascular Surg ; 39(6): 525-9, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16382274

RESUMEN

A renal artery aneurysm with an associated arteriovenous fistula in a native kidney has been reported infrequently in the literature. Management depends on size, location, and the patient's physiological condition. We describe a case in which endovascular therapy was used to successfully exclude both aneurysm and fistula. This report describes a 13-centimeter renal artery aneurysm with arteriovenous fistula originating from an isolated branch of the renal artery. Coil-embolization resulted in thrombosis of the aneurysm and fistula while preserving parenchymal perfusion. Coil embolization is an alternative to surgery for coexistent renal artery aneurysm and arteriovenous fistula arising from a branch of adequate length for placement of embolic coils. Successful treatment is not limited by aneurysm size or presence of arteriovenous connection.


Asunto(s)
Aneurisma/diagnóstico por imagen , Aneurisma/terapia , Fístula Arteriovenosa/diagnóstico por imagen , Fístula Arteriovenosa/terapia , Embolización Terapéutica/métodos , Arteria Renal , Aneurisma/complicaciones , Angiografía , Fístula Arteriovenosa/complicaciones , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Enfermedades Raras , Medición de Riesgo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
15.
Ann Vasc Surg ; 19(6): 798-804, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16200468

RESUMEN

Recent data suggest that patient age >80 years may be associated with increased risk of periprocedural complications from carotid angioplasty and stenting (CAS). In this study, we analyzed anatomic risk factors in patients undergoing CAS based on age >80 or <80 years. Our hypothesis was that patients >80 would have more challenging anatomy. Between February 2003 and August 2004, 82 patients underwent CAS. Images for 57 lesions were available for review. Eighteen patients were > or =80 years old and 39 were <80. Cerebral protection devices, including EPI Filterwire, Percusurge, Accunet, and Angioguard, were used in all but two cases; and self-expanding stents (Wallstent, NexStent, Acculink, Precise) were placed in all. Arterial anatomic characteristics were assigned a score based on complexity and associated procedural risk. Characteristics evaluated using angiographic images were aortic arch elongation classification, arch calcification, common carotid/innominate stenosis, common carotid tortuosity, internal carotid tortuosity, index lesion length, index lesion calcification, and index lesion stenosis. Statistical analysis was performed using Fisher's exact test. CAS was successfully completed in 98% of cases. The two patients in whom we could not perform CAS were 79 and 83 years old. The anatomic characteristics that were statistically significantly more complex/severe in patients > or =80 were arch calcification (p = 0.045), common carotid/innominate stenosis (p = 0.023), common carotid tortuosity (p = 0.049), and internal carotid tortuosity (p = 0.032). There was no statistically significant difference in arch elongation classification, lesion length, lesion calcification, or stenosis severity (p = nonsignificant). Overall, patients > or =80 years had an increased incidence of complex anatomic risk factors compared to younger patients (p < 0.001). Cerebrovascular accident without residual deficits occurred in two patients; both were >80 years old. Complex arterial anatomy is more often present in patients >80 years and may explain the increased complication rates associated with CAS. Pre- or intraoperative consideration of these characteristics may help provide better risk assessment in candidates for CAS.


Asunto(s)
Angioplastia de Balón , Estenosis Carotídea/terapia , Factores de Edad , Anciano , Anciano de 80 o más Años , Aorta/patología , Calcinosis , Femenino , Filtración , Humanos , Masculino , Prótesis e Implantes , Stents , Resultado del Tratamiento
16.
Vasc Endovascular Surg ; 39(5): 375-80, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16193209

RESUMEN

Critical deep venous thrombosis and occlusion constitutes a small percentage of patients with venous disease. However, these patients exhibit severe symptomatology including pain and extensive edema that may progress to limb- or life-threatening complications such as phlegmasia cerulea dolens and superior vena cava syndrome. This paper reviews the different multimodal percutaneous interventions currently available for the treatment of complex critical venous thrombotic and occlusive disease.


Asunto(s)
Extremidades/irrigación sanguínea , Trombosis de la Vena/terapia , Enfermedad Aguda , Angioplastia , Anticoagulantes/uso terapéutico , Implantación de Prótesis Vascular , Enfermedad Crónica , Terapia Combinada , Extremidades/patología , Extremidades/cirugía , Humanos , Stents , Síndrome de la Vena Cava Superior/etiología , Síndrome de la Vena Cava Superior/prevención & control , Trombectomía , Terapia Trombolítica , Tromboflebitis/etiología , Tromboflebitis/prevención & control , Venas/patología , Venas/cirugía , Filtros de Vena Cava , Trombosis de la Vena/complicaciones , Trombosis de la Vena/tratamiento farmacológico , Trombosis de la Vena/cirugía
17.
Am Surg ; 71(6): 474-9; discussion 479-80, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16044925

RESUMEN

This study analyzed clinical success, patency, and limb salvage after endovascular repair in patients treated for chronic limb ischemia presenting with claudication versus critical limb ischemia. Between October 2001 and August 2004, 115 patients (mean age 71) underwent endovascular treatment for infrainguinal arterial disease. Techniques included subintimal angioplasty and transluminal angioplasty with or without stents. Lesions were classified according to Transatlantic InterSociety Consensus. Follow-up (mean 11 months) included physical exam, ankle-brachial index, and duplex ultrasound. Patency rates were determined using Kaplan-Meier and compared by log-rank analysis. One hundred ninety-nine lesions were treated in 121 limbs using percutaneous techniques. Comorbidities were similar except higher rates of diabetes mellitus (67% vs 41%, P < 0.001) and chronic renal insufficiency (22% vs 7%, P < 0.05) were found in critical limb ischemia patients. Primary patency for claudicants was 100 per cent, 98 per cent, and 85 per cent at 3, 6, and 12 months and 89 per cent, 80 per cent, and 72 per cent for critical limb ischemia, respectively (P = 0.06). Limb salvage was 91 per cent at 12 months for critical limb ischemia patients. Morbidity was similar between groups, and there was no perioperative mortality. Percutaneous intervention for both claudication and critical limb ischemia provides acceptable 12 month patency with limited morbidity.


Asunto(s)
Angioplastia de Balón/métodos , Arteriopatías Oclusivas/terapia , Claudicación Intermitente/terapia , Isquemia/cirugía , Pierna/irrigación sanguínea , Adulto , Anciano , Anciano de 80 o más Años , Angioplastia de Balón/mortalidad , Arteriopatías Oclusivas/diagnóstico por imagen , Arteriopatías Oclusivas/mortalidad , Femenino , Humanos , Conducto Inguinal , Claudicación Intermitente/diagnóstico por imagen , Isquemia/diagnóstico por imagen , Recuperación del Miembro/métodos , Masculino , Persona de Mediana Edad , Enfermedades Vasculares Periféricas/diagnóstico por imagen , Enfermedades Vasculares Periféricas/mortalidad , Enfermedades Vasculares Periféricas/terapia , Probabilidad , Pronóstico , Estudios Prospectivos , Radiografía , Sistema de Registros , Medición de Riesgo , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Tasa de Supervivencia , Resultado del Tratamiento , Grado de Desobstrucción Vascular/fisiología
18.
Vasc Endovascular Surg ; 39(3): 273-9, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15920657

RESUMEN

Phlegmasia cerulea dolens is a limb-threatening form of deep venous thrombosis and should be treated aggressively. The authors report a patient who presented with iliocaval and femoral deep venous thrombosis and posed an additional therapeutic challenge based on a recent history of heparin-induced thrombocytopenia. Catheter-directed pharmacologic thrombolysis and balloon venoplasty were applied in treatment. The direct thrombin inhibitor argatroban was used in place of heparin for concurrent anticoagulation. This multimodality endovascular approach (chemical and mechanical interventions) was successful in relieving the venous occlusion and salvaging the limb, while maintaining appropriate treatment for heparin-induced thrombocytopenia.


Asunto(s)
Cateterismo , Vena Femoral , Vena Ilíaca , Terapia Trombolítica/métodos , Venas Cavas , Trombosis de la Vena/terapia , Anticoagulantes/uso terapéutico , Quimioterapia Combinada , Femenino , Humanos , Pierna/irrigación sanguínea , Recuperación del Miembro/métodos , Persona de Mediana Edad , Activadores Plasminogénicos/uso terapéutico , Embolia Pulmonar/terapia , Terapia Trombolítica/instrumentación , Filtros de Vena Cava
19.
J Vasc Surg ; 40(6): 1112-7, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15622364

RESUMEN

INTRODUCTION: Computer simulation has been used in a variety of training programs, ranging from airline piloting to general surgery. In this study we evaluate the use of simulation to train novice and advanced interventionalists in catheter-based techniques. METHODS: Twenty-one physicians underwent evaluation in a simulator training program that involved placement of a carotid stent. Five participants were highly experienced in catheter-based techniques (>300 percutaneous cases), including carotid angioplasty and stenting (CAS); the remaining 16 participants were interventional novices (<5 percutaneous cases). The Procedicus VIST simulator, composed of real-time vascular imaging simulation software and a tactile interface coupled to angiographic catheters and guide wires, was used. After didactic instruction regarding CAS and use of the simulator, each participant performed a simulated CAS procedure. The participant's performance was supervised and evaluated by an expert interventionalist on the basis of 50 specific procedural steps with a maximal score of 100. Specific techniques of guide wire and catheter manipulation were subjectively assessed on a scale of 0 to 5 points based on ability. After evaluation of the initial simulated CAS procedure, each participant received a minimum of 2 hours of individualized training by the expert interventionalist, with the VIST simulator. Each participant then performed a second simulated CAS procedure, which was graded with the same scale. After completion, participants assessed the training program and its utility via survey questionnaire. RESULTS: The average simulated score for novice participants after the training program improved significantly from 17.8 +/- 15.6 to 69.8 +/- 9.8 (P < .01), time to complete simulation decreased from 44 +/- 10 minutes to 30 +/- 8 minutes (P < .01), and fluoroscopy time decreased from 31 +/- 7 minutes to 23 +/- 7 minutes ( P < .01). No statistically significant difference in score, total time, or fluoroscopy time was noted for experienced interventionalists. Improvement was noted in guide wire and catheter manipulation skills in novices. Analysis of survey data from experienced interventionalists indicated that the simulated clinical scenarios were realistic and that the simulator could be a valuable tool if clinical and tactile feedback were improved. Novices also thought the simulated training was a valuable experience, and desired further training time. CONCLUSIONS: An endovascular training program using the Procedicus VIST haptic simulator resulted in significant improvement in trainee facility with catheter-based techniques in a simulated clinical setting. Novice participants derived the greatest benefit from simulator training in a mentored program, whereas experienced interventionalists did not seem to derive significant benefit.


Asunto(s)
Implantación de Prótesis Vascular/educación , Simulación por Computador , Enseñanza/métodos , Arterias Carótidas , Cateterismo , Competencia Clínica , Educación Médica/métodos , Evaluación Educacional , Cirugía General , Humanos , Internado y Residencia , Modelos Cardiovasculares , Evaluación de Resultado en la Atención de Salud , Stents
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