Ahmed Suliman - Academia.edu (original) (raw)
Papers by Ahmed Suliman
Bypass quirú rgico para el salvamento de un acceso vascular para hemodi alisis en pacientes con o... more Bypass quirú rgico para el salvamento de un acceso vascular para hemodi alisis en pacientes con obstrucció n venosa central
Annales De Chirurgie Vasculaire, 2008
Methods in Enzymology, 2008
Ischemia and ischemia-reperfusion (I/R) events are distinct but interrelated processes etiologic ... more 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.
Annals of Vascular Surgery, 2008
The National Kidney Foundation Dialysis Outcomes and Quality Initiative (DOQI) recommends autogen... more 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.
American Journal of Obstetrics and Gynecology, 2007
Massive hemorrhage from abnormal placentation is a leading cause of postpartum maternal death and... more 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.
Annals of Vascular Surgery, 2007
The etiology of spontaneous dissection of the carotid and vertebral arteries without antecedent t... more The etiology of spontaneous dissection of the carotid and vertebral arteries without antecedent trauma remains unclear. The goal of this 10-year review was to examine factors regarding presentation, diagnosis, treatment, and outcome for all patients at our institution who were diagnosed with spontaneous carotid dissections (SCD) or spontaneous vertebral dissections (SVD) with no prior trauma history. A retrospective chart analysis was performed involving all discharges from UCSD Medical Center from 1995 to 2005. Patients were selected for inclusion based on the diagnosis of carotid or vertebral dissection with no associated traumatic or iatrogenic cause for their presentation. Characteristics of these patients' medical risk factors, presenting symptoms, diagnostic method and time, treatment, and outcomes were analyzed. A total of 20 patients (10 male, age 44.8 +/À 12.9 yrs; 10 female, age 39.6 +/À 14.9 yrs) were included for study. These patients represented 12 cases of SCD and nine SVD. On presentation, a majority of patients with both SVD and SCD reported headache as their primary complaint while a significantly higher rate of nausea (25% vs. 67%, p < 0.01) was reported in SVD. SVD was associated with a significantly longer diagnostic time (11 hr vs. 16 hr, p < 0.01). The most commonly performed diagnostic exam in both SCD and SVD was magnetic resonance angiography (MRA). Anticoagulation was the primary treatment in 11 of 12 SCD and all nine SVD. One patient with persistent, symptomatic bilateral carotid dissection after anticoagulation was treated with stent placement resulting in unilateral intracranial hemorrhage (ICH). Length of stay was significantly longer in SVD (5 d vs. 7 d, p < 0.02). A significantly higher incidence of persistent neurologic deficits on discharge was seen in SCD (71% vs. 33%, p < 0.02). Radiographic evidence of cerebral infarction on discharge had a stronger correlation with clinical deficits in SCD. Although there were only two cases, those treated with endovascular therapy in the setting of SCD suffered complications related to the intervention. On discharge, there did not seem to be a correlation between persistent neurologic deficits and radiographic evidence of infarction in SVD reflecting that recovery after these episodes may not be predictable based on the appearance of the infarction.
Journal of Biochemical and Biophysical Methods, 2007
Vascular permeability is a pathologic process in many disease states ranging from metastatic prog... more Vascular permeability is a pathologic process in many disease states ranging from metastatic progression of malignancies to ischemiareperfusion injury. In order to more precisely study tissue, and more specifically cell layer permeability, our goal was to create a fluorescencebased 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 μm 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 radioactiveand 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.
Carotid angioplasty and stenting (CAS) is now a viable alternative to carotid endarterectomy (CEA... more 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. Retrospective medical record review. Academic tertiary care center. All patients 75 years or older undergoing CEA during a 16-year period. 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. 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. 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.
Annales De Chirurgie Vasculaire, 2008
ABSTRACT L'hypertension veineuse due à une obstruction veineuse centrale proximale coexis... more ABSTRACT L'hypertension veineuse due à une obstruction veineuse centrale proximale coexistant avec une fistule artérioveineuse fonctionnelle au bras homolatéral pose des problèmes de gestion complexes chez les patients hémodialysés. La ligature de la communication artérioveineuse est le procédé le plus simple pour soulager des symptômes ; cependant, ceci sacrifie l'accès pour hémodialyse, qui peut être le seul accès disponible chez le patient. La déviation chirurgicale de l'occlusion est une option potentielle car elle pallie aux symptômes de l'hypertension veineuse tout en préservant l'accès. Notre objectif était d'évaluer notre expérience et les résultats chez des dialysés subissant une déviation chirurgicale pour occlusion veineuse centrale symptomatique et sauvetage des accès pour hémodialyse. Il s'agissait de trois patients hémodialysés présentant une hypertension veineuse grave secondaire à l'obstruction de la veine sous-clavière avec une fistule artérioveineuse homolatérale fonctionnelle. Tous les patients ont eu un pontage entre la veine céphalique (n = 2) ou la veine axillaire (n = 1) et la veine jugulaire avec des prothèses en polytétrafluoroéthylène de 8 mm. Tous les patients avaient eu des échecs d'angioplastie transluminale percutanée (ATP) avant le pontage. Chez deux patients, un guide n'a pu franchir l'occlusion ; chez un tiers, l'ATL était un succès transitoire en dépit de quatre procédures répétées. Tous les patients ont eu la régression complète des symptômes sans mortalité. Les pontages sont restés perméables, permettant aux fistules artérioveineuses de fournir l'accès fonctionnel pendant la durée du suivi après chirurgie (3-8 mois). Le pontage d'une obstruction veineuse centrale corrige les symptômes d'hypertension veineuse et prolonge l'utilisation de l'accès pour hémodialyse. Cette option chirurgicale devrait être bien identifiée au sein de la communauté de dialyse.
Annals of Vascular Surgery, 2008
Annales De Chirurgie Vasculaire, 2008
etudi e s'il existait un b en efice clinique chez les malades chez lesquels etait d ecouverte de ... more etudi e s'il existait un b en efice clinique chez les malades chez lesquels etait d ecouverte de façon fortuite une st enose art erielle r enale (SAR) serr ee trait ee par angioplastie transluminale percutan ee (ATP) et stenting de l'art ere r enale lors d'une art eriographie r ealis ee pour une autre indication. Nous avons r ealis e une etude r etrospective des dossiers de tous les malades ayant eu une art eriographie r enale au cours d'une p eriode de quatre ans dans notre centre de r ef erence tertiaire acad emique. L' etude des compte-rendus d'art eriographies a et e utilis ee pour identifier les malades ayant une SAR serr ee (diminution sup erieure ou egale a 70% du diam etre de la lumi ere a l'art eriographie). Les malades trait es par ATP et stenting de l'art ere r enale ont et e identifi es. Des pressions art erielles de base et apr es la proc edure (PA, une moyenne d'au moins trois mesures ind ependantes), les d ebits de filtration glom erulaire, la cr eatinine s erique et les traitements anti-hypertenseurs ont et e compar es au cours de 12 mois de suivi. Au cours d'une p eriode de quatre ans, 124 malades ont eu une art eriographie r enale et 78 (63%) ont eu un diagnostic de SAR serr ee. Cinquante-huit malades (74% de ceux ayant une SAR serr ee) ont eu une ATP avec stenting de l'art ere r enale. Les malades trait es par ATP avec stenting avaient des caract eristiques de base semblables a ceux ayant une SAR serr ee sans intervention, a l'exception d'une PA diastolique plus basse (PAD 74 ± 11,2 versus 80 ± 14,2 mmHg, p ¼ 0,04) et une proportion plus importante d'hyperlipid emie (78% versus 55%, p ¼ 0,05). Trente-huit sur 58 malades ayant eu une ATP avec stenting (66%) ont et e suffisamment suivis pour appr ecier le r esultat. Lorsque les variables de base et apr es l'intervention etaient compar ees chez les malades ayant eu une ATP avec stenting et un suivi de 12 mois, il existait une diminution de la PA systolique (PAS 153 ± 20,8 versus 136 ± 27,2 mmHg, p ¼ 0,01) et de la pression art erielle moyenne (PAM 103 ± 11,2 versus 95 ± 14 mmhg, p ¼ 0,04). Lorsque ces malades etaient stratifi es suivant qu'ils avaient une augmentation, une diminution ou une absence de modification des traitements anti-hypertenseurs post-proc edure, des diminutions significatives de PAS, PAM et PAD n'ont et e not ees que dans la population de malades qui avaient egalement une augmentation du nombre de m edicaments anti-hypertenseurs. Aucune diff erence d'insuffisance r enale n'a et e d ecel ee. Les malades ayant une SAR serr ee d ecouverte fortuitement au cours d'une art eriographie r ealis ee pour des l esions extra-r enales et trait ees par ATP avec stenting ont eu une diminution modeste de la PA, qui n' etait significative que chez les malades ayant une augmentation du nombre de m edicaments anti-hypertenseurs apr es la proc edure. Des pr ecautions doivent ê tre prises lorsqu'on propose un stenting a des malades ayant une SAR d ecouverte fortuitement dans la mesure où les b en efices peuvent ê tre minimes par rapport au seul traitement m edical.
Journal of Vascular Surgery, 2008
Objective: The National Kidney Foundation Dialysis Outcomes and Quality Initiative recommends aut... more 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. ( J Vasc Surg 2008;48: 1245-50.)
La National Kidney Foundation Dialysis Outcomes and Quality Initiative (DOQI) recomienda las f ıs... more La National Kidney Foundation Dialysis Outcomes and Quality Initiative (DOQI) recomienda las f ıstulas aut ologas como acceso preferido para los nuevos procedimientos de di alisis. Desgraciadamente, a pesar de tener unos ındices de permeabilidad superiores a los de los implantes prot esicos, la durabilidad del acceso aut ologo suele verse minada por la hiperplasia de la ıntima de la vena eferente o por la estenosis de las venas centrales, debido a la larga permanencia de los cat eteres venosos centrales. Las intervenciones de salvamento, en forma de tratamientos endovasculares, como la angioplastia transluminal percut anea (ATP) y/o la colocaci on de stent, se utilizan cada vez m as para el salvamento y el mantenimiento del acceso. El objetivo de este estudio consisti o en evaluar la eficacia de las intervenciones endovasculares para di alisis seg un las indicaciones de la DOQI. Se realiz o una revisi on retrospectiva de una base de datos sobre intervenciones endovasculares para el acceso de di alisis durante 36 meses en un centro m edico docente. En el an alisis se incluyeron las lesiones venosas centrales y las lesiones de las venas eferentes del acceso. Se utilizaron las curvas de Kaplan-Meier y los an alisis del rango logar ıtmico para evaluar y comparar las variables dependientes del tiempo. Cuarenta y cinco pacientes con acceso para di alisis fueron sometidos a 72 intervenciones endovasculares para el mantenimiento del acceso. Se realizaron 27 procedimientos sobre venas centrales y 32 en las venas eferentes con un seguimiento del 98%. Los ındices de permeabilidad primaria y asistida de la ATP con bal on de los vasos eferentes fueron del 50 y el 72% a los 12 meses, respectivamente. Fueron necesarias 1,1 reintervenciones por cada ATP de los vasos eferentes. Los ındices de permeabilidad primaria postintervenci on de la ATP en venas centrales fueron del 30 y el 9% a los 6 y 12 meses, respectivamente. La permeabilidad asistida de la ATP postintervenci on en venas centrales fue del 100% a los 12 meses, requiriendo 1,8 reintervenciones por cada ATP. Las intervenciones de venas centrales y de venas eferentes ampliaron la permeabilidad global del acceso en 38,5 y 33 meses, respectivamente (p < 0,0001). Una adecuada estrategia en las reintervenciones resulta de vital importancia para el mantenimiento de los accesos para di alisis malfuncionantes. A pesar de que son necesarias m ultiples reintervenciones y una vigilancia estrecha, seg un las gu ıas DOQI, los procedimientos endovasculares contribuyen de forma positiva a la durabilidad del acceso para di alisis.
World Pumps, 2009
inmediata del saco sin complicaciones. Durante el seguimiento realizado a los 6 meses, la angioto... more inmediata del saco sin complicaciones. Durante el seguimiento realizado a los 6 meses, la angiotomograf ıa computerizada mostr o la permeabilidad de la endopr otesis sin signos de fuga. Dos añ os y 6 meses despu es de la intervenci on, el paciente est a vivo y se encuentra bien.
Annals of Vascular Surgery, 2008
Annals of Vascular Surgery, 2009
Blunt peripheral extremity vascular injuries are much less frequent than those of penetrating inj... more 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&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;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.
Annales De Chirurgie Vasculaire, 2009
Avulsion compl ete de l'art ere et de la veine f emorales secondaire a un traumatisme en hyperext... more Avulsion compl ete de l'art ere et de la veine f emorales secondaire a un traumatisme en hyperextension: A propos d'un cas et revue de la litt erature
Bypass quirú rgico para el salvamento de un acceso vascular para hemodi alisis en pacientes con o... more Bypass quirú rgico para el salvamento de un acceso vascular para hemodi alisis en pacientes con obstrucció n venosa central
Annales De Chirurgie Vasculaire, 2008
Methods in Enzymology, 2008
Ischemia and ischemia-reperfusion (I/R) events are distinct but interrelated processes etiologic ... more 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.
Annals of Vascular Surgery, 2008
The National Kidney Foundation Dialysis Outcomes and Quality Initiative (DOQI) recommends autogen... more 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.
American Journal of Obstetrics and Gynecology, 2007
Massive hemorrhage from abnormal placentation is a leading cause of postpartum maternal death and... more 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.
Annals of Vascular Surgery, 2007
The etiology of spontaneous dissection of the carotid and vertebral arteries without antecedent t... more The etiology of spontaneous dissection of the carotid and vertebral arteries without antecedent trauma remains unclear. The goal of this 10-year review was to examine factors regarding presentation, diagnosis, treatment, and outcome for all patients at our institution who were diagnosed with spontaneous carotid dissections (SCD) or spontaneous vertebral dissections (SVD) with no prior trauma history. A retrospective chart analysis was performed involving all discharges from UCSD Medical Center from 1995 to 2005. Patients were selected for inclusion based on the diagnosis of carotid or vertebral dissection with no associated traumatic or iatrogenic cause for their presentation. Characteristics of these patients' medical risk factors, presenting symptoms, diagnostic method and time, treatment, and outcomes were analyzed. A total of 20 patients (10 male, age 44.8 +/À 12.9 yrs; 10 female, age 39.6 +/À 14.9 yrs) were included for study. These patients represented 12 cases of SCD and nine SVD. On presentation, a majority of patients with both SVD and SCD reported headache as their primary complaint while a significantly higher rate of nausea (25% vs. 67%, p < 0.01) was reported in SVD. SVD was associated with a significantly longer diagnostic time (11 hr vs. 16 hr, p < 0.01). The most commonly performed diagnostic exam in both SCD and SVD was magnetic resonance angiography (MRA). Anticoagulation was the primary treatment in 11 of 12 SCD and all nine SVD. One patient with persistent, symptomatic bilateral carotid dissection after anticoagulation was treated with stent placement resulting in unilateral intracranial hemorrhage (ICH). Length of stay was significantly longer in SVD (5 d vs. 7 d, p < 0.02). A significantly higher incidence of persistent neurologic deficits on discharge was seen in SCD (71% vs. 33%, p < 0.02). Radiographic evidence of cerebral infarction on discharge had a stronger correlation with clinical deficits in SCD. Although there were only two cases, those treated with endovascular therapy in the setting of SCD suffered complications related to the intervention. On discharge, there did not seem to be a correlation between persistent neurologic deficits and radiographic evidence of infarction in SVD reflecting that recovery after these episodes may not be predictable based on the appearance of the infarction.
Journal of Biochemical and Biophysical Methods, 2007
Vascular permeability is a pathologic process in many disease states ranging from metastatic prog... more Vascular permeability is a pathologic process in many disease states ranging from metastatic progression of malignancies to ischemiareperfusion injury. In order to more precisely study tissue, and more specifically cell layer permeability, our goal was to create a fluorescencebased 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 μm 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 radioactiveand 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.
Carotid angioplasty and stenting (CAS) is now a viable alternative to carotid endarterectomy (CEA... more 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. Retrospective medical record review. Academic tertiary care center. All patients 75 years or older undergoing CEA during a 16-year period. 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. 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. 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.
Annales De Chirurgie Vasculaire, 2008
ABSTRACT L'hypertension veineuse due à une obstruction veineuse centrale proximale coexis... more ABSTRACT L'hypertension veineuse due à une obstruction veineuse centrale proximale coexistant avec une fistule artérioveineuse fonctionnelle au bras homolatéral pose des problèmes de gestion complexes chez les patients hémodialysés. La ligature de la communication artérioveineuse est le procédé le plus simple pour soulager des symptômes ; cependant, ceci sacrifie l'accès pour hémodialyse, qui peut être le seul accès disponible chez le patient. La déviation chirurgicale de l'occlusion est une option potentielle car elle pallie aux symptômes de l'hypertension veineuse tout en préservant l'accès. Notre objectif était d'évaluer notre expérience et les résultats chez des dialysés subissant une déviation chirurgicale pour occlusion veineuse centrale symptomatique et sauvetage des accès pour hémodialyse. Il s'agissait de trois patients hémodialysés présentant une hypertension veineuse grave secondaire à l'obstruction de la veine sous-clavière avec une fistule artérioveineuse homolatérale fonctionnelle. Tous les patients ont eu un pontage entre la veine céphalique (n = 2) ou la veine axillaire (n = 1) et la veine jugulaire avec des prothèses en polytétrafluoroéthylène de 8 mm. Tous les patients avaient eu des échecs d'angioplastie transluminale percutanée (ATP) avant le pontage. Chez deux patients, un guide n'a pu franchir l'occlusion ; chez un tiers, l'ATL était un succès transitoire en dépit de quatre procédures répétées. Tous les patients ont eu la régression complète des symptômes sans mortalité. Les pontages sont restés perméables, permettant aux fistules artérioveineuses de fournir l'accès fonctionnel pendant la durée du suivi après chirurgie (3-8 mois). Le pontage d'une obstruction veineuse centrale corrige les symptômes d'hypertension veineuse et prolonge l'utilisation de l'accès pour hémodialyse. Cette option chirurgicale devrait être bien identifiée au sein de la communauté de dialyse.
Annals of Vascular Surgery, 2008
Annales De Chirurgie Vasculaire, 2008
etudi e s'il existait un b en efice clinique chez les malades chez lesquels etait d ecouverte de ... more etudi e s'il existait un b en efice clinique chez les malades chez lesquels etait d ecouverte de façon fortuite une st enose art erielle r enale (SAR) serr ee trait ee par angioplastie transluminale percutan ee (ATP) et stenting de l'art ere r enale lors d'une art eriographie r ealis ee pour une autre indication. Nous avons r ealis e une etude r etrospective des dossiers de tous les malades ayant eu une art eriographie r enale au cours d'une p eriode de quatre ans dans notre centre de r ef erence tertiaire acad emique. L' etude des compte-rendus d'art eriographies a et e utilis ee pour identifier les malades ayant une SAR serr ee (diminution sup erieure ou egale a 70% du diam etre de la lumi ere a l'art eriographie). Les malades trait es par ATP et stenting de l'art ere r enale ont et e identifi es. Des pressions art erielles de base et apr es la proc edure (PA, une moyenne d'au moins trois mesures ind ependantes), les d ebits de filtration glom erulaire, la cr eatinine s erique et les traitements anti-hypertenseurs ont et e compar es au cours de 12 mois de suivi. Au cours d'une p eriode de quatre ans, 124 malades ont eu une art eriographie r enale et 78 (63%) ont eu un diagnostic de SAR serr ee. Cinquante-huit malades (74% de ceux ayant une SAR serr ee) ont eu une ATP avec stenting de l'art ere r enale. Les malades trait es par ATP avec stenting avaient des caract eristiques de base semblables a ceux ayant une SAR serr ee sans intervention, a l'exception d'une PA diastolique plus basse (PAD 74 ± 11,2 versus 80 ± 14,2 mmHg, p ¼ 0,04) et une proportion plus importante d'hyperlipid emie (78% versus 55%, p ¼ 0,05). Trente-huit sur 58 malades ayant eu une ATP avec stenting (66%) ont et e suffisamment suivis pour appr ecier le r esultat. Lorsque les variables de base et apr es l'intervention etaient compar ees chez les malades ayant eu une ATP avec stenting et un suivi de 12 mois, il existait une diminution de la PA systolique (PAS 153 ± 20,8 versus 136 ± 27,2 mmHg, p ¼ 0,01) et de la pression art erielle moyenne (PAM 103 ± 11,2 versus 95 ± 14 mmhg, p ¼ 0,04). Lorsque ces malades etaient stratifi es suivant qu'ils avaient une augmentation, une diminution ou une absence de modification des traitements anti-hypertenseurs post-proc edure, des diminutions significatives de PAS, PAM et PAD n'ont et e not ees que dans la population de malades qui avaient egalement une augmentation du nombre de m edicaments anti-hypertenseurs. Aucune diff erence d'insuffisance r enale n'a et e d ecel ee. Les malades ayant une SAR serr ee d ecouverte fortuitement au cours d'une art eriographie r ealis ee pour des l esions extra-r enales et trait ees par ATP avec stenting ont eu une diminution modeste de la PA, qui n' etait significative que chez les malades ayant une augmentation du nombre de m edicaments anti-hypertenseurs apr es la proc edure. Des pr ecautions doivent ê tre prises lorsqu'on propose un stenting a des malades ayant une SAR d ecouverte fortuitement dans la mesure où les b en efices peuvent ê tre minimes par rapport au seul traitement m edical.
Journal of Vascular Surgery, 2008
Objective: The National Kidney Foundation Dialysis Outcomes and Quality Initiative recommends aut... more 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. ( J Vasc Surg 2008;48: 1245-50.)
La National Kidney Foundation Dialysis Outcomes and Quality Initiative (DOQI) recomienda las f ıs... more La National Kidney Foundation Dialysis Outcomes and Quality Initiative (DOQI) recomienda las f ıstulas aut ologas como acceso preferido para los nuevos procedimientos de di alisis. Desgraciadamente, a pesar de tener unos ındices de permeabilidad superiores a los de los implantes prot esicos, la durabilidad del acceso aut ologo suele verse minada por la hiperplasia de la ıntima de la vena eferente o por la estenosis de las venas centrales, debido a la larga permanencia de los cat eteres venosos centrales. Las intervenciones de salvamento, en forma de tratamientos endovasculares, como la angioplastia transluminal percut anea (ATP) y/o la colocaci on de stent, se utilizan cada vez m as para el salvamento y el mantenimiento del acceso. El objetivo de este estudio consisti o en evaluar la eficacia de las intervenciones endovasculares para di alisis seg un las indicaciones de la DOQI. Se realiz o una revisi on retrospectiva de una base de datos sobre intervenciones endovasculares para el acceso de di alisis durante 36 meses en un centro m edico docente. En el an alisis se incluyeron las lesiones venosas centrales y las lesiones de las venas eferentes del acceso. Se utilizaron las curvas de Kaplan-Meier y los an alisis del rango logar ıtmico para evaluar y comparar las variables dependientes del tiempo. Cuarenta y cinco pacientes con acceso para di alisis fueron sometidos a 72 intervenciones endovasculares para el mantenimiento del acceso. Se realizaron 27 procedimientos sobre venas centrales y 32 en las venas eferentes con un seguimiento del 98%. Los ındices de permeabilidad primaria y asistida de la ATP con bal on de los vasos eferentes fueron del 50 y el 72% a los 12 meses, respectivamente. Fueron necesarias 1,1 reintervenciones por cada ATP de los vasos eferentes. Los ındices de permeabilidad primaria postintervenci on de la ATP en venas centrales fueron del 30 y el 9% a los 6 y 12 meses, respectivamente. La permeabilidad asistida de la ATP postintervenci on en venas centrales fue del 100% a los 12 meses, requiriendo 1,8 reintervenciones por cada ATP. Las intervenciones de venas centrales y de venas eferentes ampliaron la permeabilidad global del acceso en 38,5 y 33 meses, respectivamente (p < 0,0001). Una adecuada estrategia en las reintervenciones resulta de vital importancia para el mantenimiento de los accesos para di alisis malfuncionantes. A pesar de que son necesarias m ultiples reintervenciones y una vigilancia estrecha, seg un las gu ıas DOQI, los procedimientos endovasculares contribuyen de forma positiva a la durabilidad del acceso para di alisis.
World Pumps, 2009
inmediata del saco sin complicaciones. Durante el seguimiento realizado a los 6 meses, la angioto... more inmediata del saco sin complicaciones. Durante el seguimiento realizado a los 6 meses, la angiotomograf ıa computerizada mostr o la permeabilidad de la endopr otesis sin signos de fuga. Dos añ os y 6 meses despu es de la intervenci on, el paciente est a vivo y se encuentra bien.
Annals of Vascular Surgery, 2008
Annals of Vascular Surgery, 2009
Blunt peripheral extremity vascular injuries are much less frequent than those of penetrating inj... more 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&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;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.
Annales De Chirurgie Vasculaire, 2009
Avulsion compl ete de l'art ere et de la veine f emorales secondaire a un traumatisme en hyperext... more Avulsion compl ete de l'art ere et de la veine f emorales secondaire a un traumatisme en hyperextension: A propos d'un cas et revue de la litt erature