RESUMO
Resumo Contexto O clampeamento aórtico e a oclusão da aorta com balão poderiam levar a lesões na parede aórtica. Objetivo O objetivo deste estudo foi verificar as alterações da parede aórtica relacionadas ao método de interrupção de fluxo (cample ou balão) em diferentes técnicas disponíveis para cirurgia de aorta. Métodos Os experimentos foram realizados em 40 porcos fêmeas pesando de 25-30 kg, alocados para quatro grupos: S (n = 10), nenhuma intervenção (sham); C (n = 10), laparotomia mediana transperitoneal para acesso à aorta abdominal infrarrenal com tempo de clampeamento de 60 minutos; L (n = 10), cirurgia laparoscópica da aorta abdominal infrarrenal com tempo de clampeamento de 60 minutos; EV (n = 10), controle aórtico proximal com inserção de cateter-balão para oclusão aórtica por acesso femoral, inflado a fim de promover oclusão aórtica contínua por 60 minutos. Após a eutanásia, as aortas foram removidas e seccionadas para obtenção de espécimes histológicos destinados a análises morfométricas e por microscopia de luz. Os fragmentos longitudinais restantes foram estirados até a ruptura, e determinaram-se padrões mecânicos. Resultados Observou-se redução do limite de proporcionalidade da aorta abdominal, diminuição da rigidez e da carga de ruptura nos grupos submetidos a campleamento aórtico (C e L) em comparação ao grupo EV. Conclusões O campleamento aórtico durante cirurgia aberta ou laparoscópica pode afetar as propriedades mecânicas da aorta, ocasionando redução de resistência da parede aórtica sem desencadear alterações na estrutura histológica da parede aórtica.
Abstract Background Aortic cross-clamping and balloon occlusion of the aorta could lead to damage to the aorta wall. Objective The aim of this study was to investigate changes to the aorta wall related to the method used to interrupt flow (clamping or balloon) in the different techniques available for aortic surgery. Methods Experiments were performed on 40 female pigs, weighing 25-30kg, which were randomly allocated to 4 study groups: S (n=10), no intervention (sham group); C (n=10), midline transperitoneal laparotomy for infrarenal abdominal aortic access with 60 min of cross-clamping; L (n=10), laparoscopic infrarenal abdominal aortic surgery with 60 min of cross-clamping; EV (n=10), remote proximal aortic control with transfemoral arterial insertion of aortic occlusion balloon catheter, inflated to provide continued aortic occlusion for 60min. After euthanasia, the aortas were removed and cross-sectioned to obtain histological specimens for light microscopic and morphometric analyses. The remaining longitudinal segments were stretched to rupture and mechanical parameters were determined. Results We observed a reduction in the yield point of the abdominal aorta, decrease in stiffness and in failure load in the aortic cross-clamping groups (C and L) compared with the EV group. Conclusions Aortic cross-clamping during open or laparoscopic surgery can affect the mechanical properties of the aorta leading to decrease in resistance of the aorta wall, without structural changes in aorta wall histology.
Assuntos
Animais , Feminino , Aorta Abdominal/lesões , Procedimentos Cirúrgicos Cardiovasculares/instrumentação , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Estresse Mecânico , Suínos , Resistência à Tração , Estudos Prospectivos , Modelos Animais , Dispositivos de Oclusão Vascular/efeitos adversosRESUMO
Obstructive sleep apnea (OSA) is an independent risk factor for cardiovascular diseases such as systemic arterial hypertension, ischemic heart disease, stroke, heart failure, atrial fibrillation, and cardiac sudden death. The pathogenesis of cardiovascular disease in OSA is thought to be induced primarily by chronic intermittent hypoxia (CIH), a specific pattern of change in oxygenation during sleep. However, the underlying mechanisms of CIH-induced vasculature injury and gender differences are not well documented. The iTRAQ Quantitative Proteomic method enables analysis of a number of different proteins among several groups. Thus, we explored gender differences in protein expression in the vascular walls of mice exposed to CIH. C57BL/6J mice of each gender were exposed to CIH with a fractional inspired O2 (FiO2) nadir of 5% or control, with a treatment time of 8 h/day for 28 days. Differential proteins related to CIH-induced vascular injury between genders were identified using iTRAQ proteomic technology. A total of 163 proteins were identified, of which 34 showed significant differences between genders, which may correlate with vascular injury by CIH. Twenty up-regulated proteins and 14 downregulated proteins were observed in female mice compared with male mice. We identified different vascular proteins expressed under CIH between genders, suggesting that these proteins may be biomarkers of vascular injury by CIH.
Assuntos
Aorta Abdominal/metabolismo , Hipóxia/metabolismo , Proteoma , Proteômica , Animais , Aorta Abdominal/lesões , Aorta Abdominal/patologia , Biologia Computacional , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Proteômica/métodos , Fatores Sexuais , Apneia Obstrutiva do Sono/metabolismoRESUMO
Embolization due to a firearm projectile entering the bloodstream is a rare event that is unlikely to be suspected during initial treatment of trauma patients. We describe and discuss a case of bullet embolism of the abdominal aortic bifurcation, complicated by a pseudoaneurysm of the thoracoabdominal aorta and occlusion of the right common iliac artery, but successfully treated using a combination of endovascular methods and conventional surgery.
A embolização por projétil de arma de fogo na circulação sanguínea é rara e de difícil suspeição no atendimento inicial ao trauma. Relatamos e discutimos um caso de embolia em bifurcação aórtica abdominal complicada com pesudoaneurisma de aorta tóraco-abdominal e oclusão de artéria ilíaca comum direita, tratada de forma efetiva pelos métodos endovascular e cirúrgico convencional.
Assuntos
Humanos , Masculino , Adolescente , Aorta Abdominal/lesões , Artéria Ilíaca/lesões , Embolia/complicações , Ferimentos por Arma de Fogo/cirurgia , Procedimentos Endovasculares/reabilitação , Falso Aneurisma , Raios X/efeitos adversosRESUMO
Abdominal aortic pseudoaneurysm (AAP) is a rare lesion, although traumatic aortic injury is described as one of the main causes; both the rupture as the surgical treatment of the defect has high morbidity and mortality. Therefore, endovascular treatment either by chemical embolization or exclusion of defect with devices has emerged as an alternative treatment. However, there are risks such as occlusion of visceral vessels near the neck of the defect, embolization material or aortic rupture. Therefore, the choice of material and method of approach should be planned carefully in each case. We report a patient who ten years after abdominal wound firearm was diagnosed with AAP 17 x 13 cm, with short neck originated close to the ostium of the celiac trunk at an acute angle with the aortic axis. We perform the exclusion of the defect with a device designed for closing atrial septal defect from the left brachial access due to the angulation of the neck defect. There were no complications. At 72 hours was granted discharge. A month later, CT scan control showed the false aneurysm of equal size and no residual flow. The monitoring to date is five months and the patient remained asymptomatic.
Assuntos
Falso Aneurisma/cirurgia , Aorta Abdominal/lesões , Doenças da Aorta/cirurgia , Adulto , Artéria Braquial , Feminino , Humanos , Procedimentos Cirúrgicos Vasculares/métodosRESUMO
The aim of the present work is to describe the integration of a mathematical model for the baroreceptor reflex mechanism to provide regulatory action into a dimensionally heterogeneous (3D-1D-0D) closed-loop model of the cardiovascular system. Such heterogeneous model comprises a 1D description of the arterial tree, a 0D network for the venous, cardiac and pulmonary circulations and 3D patient-specific geometries for vascular districts of interest. Thus, the detailed topological description of the arterial network allows us to perform vasomotor control actions in a differentiated way, while gaining insight about the effects of the baroreflex regulation over hemodynamic quantities of interest throughout the entire network. Two examples of application are presented. Firstly, we simulate the hemorrhage in the abdominal aorta artery and analyze the action of the baroreflex over the system. Secondly, the self-regulated closed-loop model is applied to study the influence of the control action in the hemodynamic environment that determines the blood flow pattern in a cerebral aneurism in the presence of a regurgitating aortic valve.
Assuntos
Barorreflexo/fisiologia , Hemostasia/fisiologia , Modelos Cardiovasculares , Aorta Abdominal/lesões , Pressão Sanguínea/fisiologia , Volume Sanguíneo/fisiologia , Hemorragia/fisiopatologia , Humanos , Sistema Vasomotor/fisiologia , Função Ventricular Esquerda/fisiologiaRESUMO
Sudan-positive atherosclerotic lesions preferentially occur at downstream and lateral margins of arterial branch ostia in human neonates and weanling rabbits but tend to develop at lateral and upstream margins in old subjects. We investigated (i) the pattern of sudanophilic lesions at aortic ostia of cholesterol-fed adult rabbits and (ii) determined any differences in lesion distribution between descending thoracic and abdominal aorta. Ten adult males, New Zealand white rabbits were fed 2 percent high cholesterol diet. After six weeks, aortas were excised, opened longitudinally and stained with Sudan-IV for gross examination of atherosclerotic lesions. A total of 156 descending thoracic and 90 abdominal ostia were examined. Mean lesion frequencies upstream, downstream and at lateral margins of the affected ostia were calculated and compared. Sudanophilic lesions were detected around 32 percent ostia of descending thoracic aorta and 25 percent those of abdominal aorta. At ostia of descending thoracic aorta, lesion frequencies were significantly higher (P<0.001) downstream (95 percent) and at lateral margins (92 percent) than upstream (2 percent). In abdominal aorta, lateral (100 percent) and upstream (43 percent) margins were significantly (P<0.05) more affected while minimal lesion frequencies were seen at downstream branch points (9 percent). Comparison between descending thoracic and abdominal aorta showed an insignificant difference of lesion frequencies at lateral margins (P>0.05) but a highly significant difference at upstream versus downstream of ostia (P<0.001). We concluded that in cholesterol-fed adult rabbits, juvenile pattern of downstream lipid deposition persists at ostia of descending thoracic aorta while a switch towards the upstream pattern of old subjects occurs at ostia of abdominal aorta.
Las lesiones ateroscleróticas Sudán-positivas se producen preferentemente en los márgenes posteriores y laterales del ostio de las ramas arteriales en neonatos humanos y en conejos destetados, pero tienden a desarrollarse en los márgenes laterales y superiores en sujetos de edad avanzada. Investigamos el patrón de lesiones sudanofílicas en el ostio aórtico de conejos adultos alimentados con colesterol y determinamos las diferencias en la distribución de lesiones entre la aorta torácica descendente y abdominal. Diez conejos machos blancos adultos New Zealand fueron alimentados con una dieta alta en colesterol al 2 por ciento. Después de seis semanas, fueron extraídas las aortas, se disecaron longitudinalmente y se tiñeron con Sudan-IV para el examen macroscópico y se observaron las lesiones ateroscleróticas. Fueron examinados 156 ostios de aortas torácicas descendentes y 90 de aortas abdominales. Fueron calculadas y comparadas las frecuencias medias de lesiones superiores, inferiores y de los márgenes laterales de los ostios afectados. Las lesiones sudanofílicas se detectaron en alrededor del 32 por ciento de ostios de la aorta torácica descendente y en el 25 por ciento de las aortas abdominales. En el ostio de la aorta torácica descendente, las frecuencias de lesiones fueron significativamente mayores (p <0,001) por superior (95 por ciento) y en los márgenes laterales (92 por ciento) que por inferior (2 por ciento). En la aorta abdominal, los márgenes laterales (100 por ciento) y superiores (43 por ciento) fueron significativamente más afectados (p <0,05), mientras que las frecuencias mínimas de lesiones se observaron en los puntos de la rama descendente (9 por ciento). La comparación entre la aorta torácica descendente y abdominal mostró una diferencia no significativa de las frecuencias de lesiones en los márgenes laterales (p> 0,05), pero muy significativa al comparar el margen superior con el inferior (p <0,001). Llegamos a la conclusión que en los conej...
Assuntos
Masculino , Adulto , Animais , Feminino , Coelhos , Aorta Abdominal/lesões , Traumatismos Torácicos , Colesterol/administração & dosagem , Colesterol/uso terapêutico , Coelhos/lesõesRESUMO
Síndrome da aorta média (SAM) é uma condição clínica caracterizada por estenose segmentar ou difusa da aorta, hipertensão arterial e claudicação de membros inferiores. A principal causa da SAM é a arterite de Takayasu. A estenose segmentar pode estar localizada na aorta suprarrenal, renal ou infrarrenal e com alta propensão de lesões estenóticas concomitantes das artérias renais e viscerais. A gravidade da hipertensão arterial é a principal indicação para o tratamento. A técnica endovascular para o tratamento da síndrome da aorta média tem bons resultados e é a menos invasiva. No presente artigo, é descrito o tratamento com sucesso de uma estenose da aorta toracoabdominal com recanalização da artéria mesentérica superior através de angioplastia em uma mulher de 34 anos portadora de arterite de Takayasu e hipertensão arterial grave.
Middle aortic syndrome (MAS) is a clinical condition characterized by segmental or diffuse narrowing of the aorta, hypertension, and lower limb claudication. The main cause of MAS is Takayasu's arteritis. Segmental aortic stenosis may be located at the suprarenal, renal or infrarenal aorta with high tendency to concomitant stenosis in both the renal and visceral arteries. Severity of hypertension is the primary indication for intervention. Endovascular therapy is a minimally invasive treatment for MAS and may provide good results. In the present report, we describe a successful endovascular treatment of stenosis of the thoracoabdominal aorta with recanalization of the superior mesenteric artery using angioplasty in a 34-year-old woman with Takaysu's arteritis and severe hypertension.
Assuntos
Humanos , Feminino , Adulto , Angioplastia com Balão/métodos , Angioplastia com Balão , Aorta Abdominal/lesões , Arterite de Takayasu/complicações , Arterite de Takayasu/diagnóstico , Stents , Obstrução da Artéria Renal/complicações , Obstrução da Artéria Renal/diagnósticoRESUMO
Traumatic injury of the abdominal aorta with total interruption of blood flow is uncommon. When there is total obstruction of the artery, the clinical picture is dramatic. The most frequent mechanism is compression due to the safety belt during a car accident. The patients have absent femoral and distal pulses, associated to neuropathy in the lower limbs. We present a case of abdominal aorta injury secondary to closed trauma and review the causes, presentation forms and management of the injury.