Pseudoaneurisma para-anastomótico gigante tras revascularización por baipás aorto-bifemoral: Informe de un caso / Giant para-anastomotic pseudoaneurysm after revascularization though aorto-bifemoral bypass grafting: Case report

RESUMEN El pseudoaneurisma es aquel hematoma pulsátil y encapsulado producido tras la rotura de todas las túnicas del vaso y contenido por tejidos vecinos circundantes. Es considerado una complicación tardía en la cirugía protésica aorto-ilíaca. Se presenta un paciente de 72 años al que se le realizó un baipás aorto-bifemoral 13 años atrás, y que posteriormente se le diagnosticó un pseudoaneurisma para-anastomótico que se dejó evolucionar por presentar varias comorbilidades asociadas. Transcurridos 2 años fue necesario realizarle una intervención quirúrgica por presentar crecimiento excesivo de la tumefacción y complicación isquémica con necrosis cutánea. La aparición de un pseudoaneurisma está relacionada con el sexo, el material protésico y con el tiempo que transcurre desde la cirugía. El seguimiento ultrasonográfico durante el postoperatorio es primordial para identificar tempranamente esta complicación.

ABSTRACT Pseudoaneurysm is that pulsatile and encapsulated hematoma produced after the rupture of all vessel layers and contained by surrounding neighboring tissues. It is considered a late complication in aorto-iliac prosthetic surgery. We present a 72-year-old patient who underwent an aorto-bifemoral bypass grafting 13 years ago, and who was subsequently diagnosed with a para-anastomotic pseudoaneurysm that was allowed to evolve due to presenting several associated comorbidities. After two years, it was necessary to perform a surgical intervention due to the excessive growth of the swelling, and ischemic complication with skin necrosis. The appearance of a pseudoaneurysm is related to sex, prosthetic material as well as the time that elapses since the surgery. Ultrasound follow-up during the postoperative period is essential for an early identification of this complication.

Seudoartrosis del escafoides: experiencia con injerto óseo vascularizado del primer metacarpiano. Serie de casos / Scaphoid pseudoarthrosis: experience with vascularized bone graft of the first metacarpal. Case series

Introducción describir los resultados clínicos, funcionales y radiológicos de pacientes con seudoartrosis de fractura del escafoides, sometidos a cirugía con la técnica de Bertelli. en un centro de cuarto nivel de complejidad. Materiales & Métodos Serie de casos en un centro de cuarto nivel de complejidad entre el 2005 y 2016 de pacientes con fractura de escafoides en seudoartrosis sometidos a cirugía de revisión con injerto vascularizado de la primera arteria dorsal metacarpiana según la técnica de Bertelli. Se tomaron datos de historias clínicas, que se analizaron con medidas descriptivas de resumen. Resultados se analizaron 11 pacientes con una edad promedio de 30,1 años. El 72,7% fue llevado a osteosíntesis como manejo inicial. El procedimiento de revisión se realizó en una mediana de 380 días. Se reportaron complicaciones pos-quirúrgicas: necrosis del injerto en un paciente, necesidad de re-intervención en cuatro y no hubo infecciones. En el 72,7% se observó consolidación de la fractura y ocurrió en promedio a los 7,6 meses. La mitad de los pacientes tuvieron un puntaje DASH de 9 o menos y reportaron percepción de dolor leve - moderado el 90,9%. La mediana de seguimiento fue 14 meses. Discusión la ventaja de esta técnica es su reproducibilidad y versatilidad, pues su pedículo vascular constante y de buena longitud, permite utilizarse por un abordaje dorsal o palmar y para no consolidaciones del polo proximal, cintura o polo distal del escafoides. Este estudio mostró buenos resultados clínicos y funcionales, asociados a una baja tasa de complicaciones. Nivel de evidencia IV

Background The aim of study is to describe the clinical, functional, and radiological results in patients with pseudoarthrosis of scaphoid fractures who that underwent surgery using Bertelli's et al. technique. Methods Case series of patients with nonunion of scaphoid fractures in a high complexity care center between 2005 and 2016, who underwent revision surgery with vascularized bone graft of the first metacarpal dorsal artery according to Bertelli's et al. technique. Data were collected from clinical records, and it waswere analyzed using descriptive summary measures. Results The analysis included 11 patients with a mean age of 30,1 years (S.D: 9). 72,7% of the patients underwent conventional osteosynthesis as the initial approach. The revision surgery was performed with a median of 380 days (interquartile range: 194-470); there were no intraoperative complications. Post- surgery complications, such as graft necrosis, were reported in a one patient (9,1%), the need of for re-intervention in four patients and there were no infection related complications. Fracture union was seen in 72,7% patients in a mean of 7,6 months (S.D: 2,9) after the intervention. Half of the patient had a DASH score of 9 points or less. 54,5 reported pain as mild, 36,4% as moderate and without pain 9,1%. The median follow up period was 14 months and only one patient developed carpal arthritis. Discussion The advantage of this surgical technique is its reproducibility and versatility, thanks due to the constant and long vascular pedicle; this allows using dorsal or palmar approaches, as well as for the management of scaphoid nonunions of the proximal pole, waist, or distal pole. This study shows good clinical and functional results outcomes with a low rate of complications. Evidence Level IV

Injerto Heterólogo (PTFE) vs Injerto Autólogo (Vena Safena) en trauma vascular de miembros inferiores en Hospital Nacional Rosales, de enero 2015 a septiembre de 2019 / Heterologous graft (PTFE) vs Autologous Graft (Saphenous Vein) in vascular trauma of the lower limbs at Rosales National Hospital, from January 2015 to September 2019

El trauma vascular de extremidades inferiores puede resultar en muerte, discapacidad severa o pérdida del miembro. Las lesiones tipo C3 requieren de colocación de un injerto para su reparación, los cuales pueden ser autólogos o heterólogos. Ambos injertos han sido comparados en cirugía electiva, pero no han sido estudiados en contexto de trauma vascular, por lo que se plantea el presente estudio con el objetivo de Identificar cuál tipo de injerto de reconstrucción vascular, autólogo o heterólogo, tiene más beneficios y seguridad en lesiones vasculares de miembros inferiores, en pacientes del Hospital Nacional Rosales de enero de 2015 a septiembre de 2019. Se utilizó un diseño analítico de cohortes retrospectivas, según injerto utilizado: injertos heterólogos contra autólogos, y comparando los eventos: trombosis del injerto, isquemia del miembro, reintervenciones, amputaciones, tiempo de cirugía y mortalidad. Se incluyó un total de 43 pacientes: 21 en el grupo de injerto autólogo y 22 en el heterólogo. No se encontró diferencias en relación a trombosis entre ambos grupos [18% vs 10%, p=0.664 OR=2.111 (0.344-12.973)], isquemia [18% vs 10%, p=0.664 OR=2.111 (0.344-12.973)], infección de sitio operatorio [10% vs 5%, p=1.000 OR=2.000 (0.168-23.863)], reintervención [24% injerto autólogo, 27% injerto heterólogo, p=1.000 OR=0.833 (0.211-3.294)] y amputación 10% vs 14% [p=1.000 OR=0.667 (0.100-4.452)]. Hubo 3 fallecidos en el grupo de injerto heterólogo (p=0.233). No se encontró diferencias en los resultados en el uso de ambos injertos, pero los datos no son concluyentes ya que los pocos casos pudieron generar dichos resultados

Decellularization of human umbilical arteries / Descelularización de las arterias umbilicales humanas

SUMMARY: Arterial obstruction in small diameter (<6 mm) vessels are many times treated with grafts, however autologous aren't always available and synthetic have a high rate of complications. Decellularization of umbilical arteries may provide a solution, but the ideal method is debatable. We compare effectiveness between SDS and Triton X-100. Umbilical cords obtained from full term pregnancies with normal development and no evident complications in the newborn, were micro-dissected within 12 h and stored in phosphate buffered saline without freezing. Arteries were then processed for decellularization using 0.1 % and 1 % SDS, and 1 % Triton X100 protocols. Evaluation of cellular and nuclear material, collagen fibers, elastic fibers, and glycosoaminoglycans of the extracellular matrix (ECM) were evaluated as well as morphometric analysis under histological and immunohistochemical techniques. Triton X-100 was ineffective, preserving nuclear remains identified by immunofluorescence, had the most notable damage to elastic fibers, and decrease in collagen. SDS effectively eliminated the nuclei and had a less decrease in elastic fibers and collagen. Laminin was preserved in all groups. No significant differences were identified in luminal diameters; however the middle layer decreased due to decellularization of muscle cells. In conclusion, 0.1 % SDS decellularization was the most effective in eliminating cells and preserving the main components of the ECM.

RESUMEN: La obstrucción arterial en vasos de pequeño diámetro (<6 mm) se trata muchas veces con injertos, sin embargo, los autólogos no siempre están disponibles y los sintéticos tienen una alta tasa de complicaciones. La descelularización de las arterias umbilicales puede proporcionar una solución, pero el método ideal es discutible. Comparamos la efectividad entre los métodos SDS y Triton X-100. Cordones umbilicales obtenidos a partir de embarazos a término con evolución normal y sin complicaciones evidentes del recién nacido, se microdiseccionaron en 12 horas y se almacenaron en solución salina con fosfato sin congelación. Las arterias se procesaron luego para la descelularización usando los protocolos de SDS al 0,1 % y 1 %, y Triton X-100 al 1 %. Se realizó la evaluación de material celular y nuclear, fibras de colágeno, fibras elásticas y glucosoaminoglicanos de la matriz extracelular (MEC), así como el análisis morfométrico bajo técnicas histológicas e inmunohistoquímicas. Triton X-100 fue ineficaz, conservando los restos nucleares identificados por inmunofluorescencia, tuvo el daño más notable a las fibras elásticas y la disminución del colágeno. SDS efectivamente eliminó los núcleos y tuvo una disminución menor en las fibras elásticas y el colágeno. Laminina fue preservado en todos los grupos. No se identificaron diferencias significativas en los diámetros luminales; sin embargo, la capa media disminuyó debido a la descelularización de las células musculares. la descelularización con SDS al 0,1 % fue la más efectiva para eliminar células y preservar los principales componentes de la MEC.

Doença cística adventicial da artéria poplítea: relato de caso / Adventitial cystic disease of the popliteal artery: case report

A doença cística adventicial da artéria poplítea é uma doença pouco frequente, que deve ser considerada no diagnóstico diferencial de pacientes jovens com claudicação intermitente e sem fatores de risco para doença arterial periférica aterosclerótica. Apresentamos um caso de claudicação intermitente de membros inferiores em paciente masculino de 51 anos no qual essa doença foi diagnosticada. Foi submetido a ressecção do segmento de artéria comprometido e interposição de safena autóloga ipsilateral. Discutimos alternativas diagnósticas e terapêuticas

Adventitial cystic disease of the popliteal artery is an uncommon pathology that should be considered in differential diagnostic of younger patients with intermittent claudication and without risk factors for peripheral atherosclerotic arterial disease. We report the case of a 51 year-old male patient presenting with lower-limb intermittent claudication in whom this pathology was diagnosed and who was treated with segmental arterial resection and autologous saphenous vein interposition. We also discuss diagnostic and therapeutic alternatives

Estudo experimental de reconstrução da veia femoral com enxerto tubular do bipolímero de cana-de-açúcar / Experimental study of femoral vein reconstruction with sugarcane biopolymer tubular graft

RESUMO Objetivo: avaliar, através de dopplerfluxometria, de venografia, de histologia e de evolução clínica, o uso de enxertos tubulares de biopolímero de cana-de-açúcar (BP) na reconstrução de veias femorais em cães. Métodos: oito cães adultos foram submetidos à reconstrução de veia femoral, à esquerda com enxerto tubular de BP e à direita com veia autóloga. No período pós-operatório, os animais foram submetidos à avaliação clínica e dopplerfluxometria das veias femorais. Após 360 dias, os cães foram reoperados e submetidos à flebografia das veias femorais com contraste iodado. Os segmentos das veias femorais contendo os enxertos foram retirados e enviados para avaliação histopatológica. Resultados: os cães não apresentaram hemorragia, hematoma, infecção da ferida operatória ou edema dos membros operados. Um animal apresentou dilatação venosa superficial na região inguinal esquerda. A flebografia realizada 360 dias após a primeira cirurgia demonstrou que três (37,5%) enxertos de BP e sete (87,5%) do grupo controle (C) estavam pérvios. Na avaliação histopatológica foi encontrada uma reação inflamatória com neutrófilos e linfócitos na superfície externa de ambos os grupos. Na camada íntima de revestimento dos enxertos e na camada externa nos dois grupos, foi encontrada fibrose. Conclusão: com base nos resultados obtidos com o modelo experimental utilizado, conclui-se que a BP apresenta potencial para ser utilizado como enxerto tubular para revascularização venosa, porém novas pesquisas precisam ser realizadas para confirmar a sua eficácia na revascularização de veias de médio e grande calibre, o que poderia permitir o seu uso na prática clínica.

ABSTRACT Objective: to evaluate, through Doppler flowmetry, venography, histology and clinical evolution, the use of sugarcane biopolymer (BP) tubular grafts in the reconstruction of femoral veins in dogs. Methods: we submitted eight adult dogs to femoral vein reconstruction, on the left with BP tubular graft and on the right with autologous vein. In the postoperative period, the animals underwent clinical evaluation and femoral vein Doppler flowmetry. After 360 days, we reoperated the dogs and submitted them to femoral vein phlebography with iodinated contrast. We removed the segments of the femoral veins containing the grafts and sent them for histopathological evaluation. Results: the dogs did not present hemorrhage, hematoma, surgical wound infection or operated limb edema. One animal had superficial venous dilatation in the left inguinal region. Phlebography performed 360 days after the first surgery showed that three (37.5%) BP grafts and seven (87.5%) grafts from the control group (C) were patent. In the histopathological evaluation, we found an inflammatory reaction, with neutrophils and lymphocytes on the external surface of both groups. In the intimal layer of the grafts and in the outer layer in the two groups, we observed fibrosis. Conclusion: based on the results obtained with the experimental model used, BP presents potential to be used as a tubular graft for venous revascularization. However, new research must be performed to confirm its efficacy in the revascularization of medium and large diameter veins, which could allow its use in clinical practice.

Experimental study of histological changes in vascular loops according to the duration of the postoperative period: Application in reconstructive microsurgery

OBJECTIVES: To analyze the histological changes observed in venous grafts subjected to arterial blood flow as a function of the duration of the postoperative period to optimize their use in free flap reconstructions. METHOD: Twenty-five rats (7 females and 18 males) underwent surgery. Surgeries were performed on one animal per week. Five weeks after the first surgery, the same five animals were subjected to an additional surgery to assess the presence or absence of blood flow through the vascular loop, and samples were collected for histological analysis. This cycle was performed five times. RESULTS: Of the rats euthanized four to five weeks after the first surgery, no blood flow was observed through the graft in 80% of the cases. In the group euthanized three weeks after the first surgery, no blood flow was observed in 20% of the cases. In the groups euthanized one to two weeks after the first surgery, blood flow through the vascular loop was observed in all animals. Moreover, intimal proliferation tended to increase with the duration of the postoperative period. Two weeks after surgery, intimal proliferation increased slightly, whereas strong intimal proliferation was observed in all rats evaluated five weeks after surgery. CONCLUSION: Intimal proliferation was the most significant change noted in venous grafts as a function of the duration of the postoperative period and was directly correlated with graft occlusion. In cases in which vascular loops are required during free flap reconstruction, both procedures should preferably be performed during the same surgery.

Histomorphometric and immunohistochemical study of early adaptative response of the vascular wall in a termino-terminal microsurgical model of femoral vessels in Wistar rat / Estudio histomorfométrico e inmunoistoquímico de la respuesta adaptativa temprana de la pared vascular en un modelo microquirúrgico termino-terminal de los vasos femorales en rata Wistar

When a vein segment is grafted into arterial circulation, biomechanical forces stimulate modification of its structure. This morphological adaptive response is progressive during a medium or long term and occludes the vessel lumen, leading to a graft failure. The objective of this study was to characterize the early morphological response of the vascular wall in a terminal-terminal vascular vein graft model in Wistar rats. A segment of the femoral vein was placed in the femoral circulation. An end to end microsurgical graft anastomosis technique was implemented and standardized in twenty rats. The samples were processed with histological technique to analyze the overall structure with hematoxylin and eosin, the composition of the vessel wall with Masson trichrome technique, the proliferating and smooth muscle cells were detected with immunohistochemistry (anti-PCNA, anti-actin and anti CD68) and the induction of apoptosis with TUNEL technique. The times periods studied were 1, 3 and 5 days postoperative. There is progressive increase of cell proliferation and intensity of the density detected by PCNA with its peak at postoperative day 3. Apoptosis was not evident in any of the postoperative days. Smooth muscle had no significant change in any of the time periods studied. Macrophage and leukocyte migration was evident since the first postoperative day with infiltration into the media by the 5th day. This study characterizes the morphological aspects in the early arterialization of the vascular wall in a vein graft process. These results contribute to a better understanding of the morphopathological mechanism involved in vein graft failure.

Cuando un segmento venoso es injertado dentro de la circulación arterial, se generan fuerzas biomecánicas que estimulan modificaciones en su estructura. Esta respuesta morfológica adaptativa es progresiva a mediano y largo plazo y termina por ocluir la luz del vaso, conduciendo a la falla del injerto. El objetivo de este estudio fue caracterizar la respuesta morfológica adaptativa temprana de la pared vascular en un modelo de injerto vascular venoso termino-terminal en ratas Wistar. Un segmento de la vena femoral se coloco en la circulación arterial femoral. Una anastomosis del injerto microquirúrgica termino-terminal fue implementada y estandarizada en veinte ratas. Las muestras se procesaron con la técnica histológica para analizar su estructura general con la tinción de hematoxilina y eosina, la composición de la pared vascular con la técnica de tricromico de Masson , la proliferación y las células de musculo liso fueron detectadas mediante técnicas inmunohistoquimicas (anti PCNA, anti-actina y anti CD68) y la inducción de la apoptosis mediante la técnica de TUNEL. Los tiempos de estudio fueron al día 1, 3 y 5 postoperatorios. Hay un incremento progresivo en la proliferación celular y la intensidad de la densidad detectado mediante PCNA con un pico en el día 3 postoperatorio. La apoptosis no fue evidente en ninguno de los días postoperatorios. Las células de musculo liso no tuvieron un cambio significativo en ninguno de tiempos de estudio. La migración de macrófagos y leucocitos fue evidente desde el primer día postoperatorio con infiltración a la túnica media al 5to día. Conclusiones. Este estudio caracteriza los aspectos morfológicos en el proceso de arterialización temprana de la pared vascular en un injerto venoso. Estos resultados contribuyen al mejor entendimiento de los mecanismos morfopatológicos envueltos en la falla del injerto venoso.

The effects of ozone on bacterial growth and thiol-disulphide homeostasis in vascular graft infection caused by MRSA in rats

Abstract: Purpose: To investigate the microbiological, inflammatory and oxidant effects of adjuvant ozone administration in experimental rat vascular graft infection model which has not been previously investigated. Methods: Forty adult Wistar rats were divided into Sham, Control, Vancomycin, Ozone, Vancomycin+Ozone groups. Grafts were inoculated with Methicillin-resistant Staphylococcus aureus (MRSA) strain and implanted subcutaneously. Rats were treated intraperitoneally with ozone and /or intramuscularly with vancomycin for 10 days. Grafts were evaluated by quantitative bacterial cultures. Blood samples were harvested for determination of thiol-disulphide and cytokine profiles. Results: There was no significant difference in bacterial counts between Control and Ozone Groups. In the Ozone Group median colony count was significantly higher than the Vancomycin and Vancomycin+Ozone Groups. Total thiol and disulphide levels increased and disulphide/native thiol and disulphide/total thiol ratios decreased in Ozone Group significantly. Albumin levels decreased significantly in Vancomycin and Vancomycin+Ozone Groups compared to the Sham Group. IL-1 and TNF-alpha levels significantly increased in infected rats. Decreased levels of VEGF due to infection reversed by ozone therapy in control and vancomycin groups. Conclusions: We didn't observe any benefit of the agent on MRSA elimination in our model. Likewise, effects of ozone on thiol-disulphide homeostasis and inflammatory cytokines were contradictory.

A necktie fashion vascular loop seton tie may simplify the treatment of perianal fistula / O seton para alça vascular com laçada em forma de nó de gravata pode simplificar o tratamento da fístula perianal

ABSTRACT Seton for treatment of perianal fistula can be of the cutting or a loose type. We adopted a simple technique for tighten the seton by applying a necktie shape tie on the vascular loop, hence it can be used for drainage on the beginning, and for cutting purpose later on. In this retrospective study we report our experience on this seton tie method. Material and methods: Patients operated for perianal fistula between 2012 and 2014 were reviewed. Results: Of 63 patients operated, 23 (35%) had a necktie-tie seton. There were 15 (65%) men. Age 34.1 ± 10.6. Six (26%) had a recurrent fistula, 2 (9%) with loose seton in place. The external opening: anterior four (17%), lateral fifteen (65%), posterior three (13%), one patient (4%) had two opening. The internal opening was identified: posterior seventeen (74%), anterior four (17%) and right posterior two (8%). Nineteen (82%) had a trans-sphenteric tract, four (17%) females had an anterior location. Operative time was 32 min (range 22-55). The seton was tightened 4 times (range 2-5) with 2 weeks interval. Healing was achieved in 7 weeks (range 5-11). In 24 months (range 12-35) follow-up, no reported anal incontinence. Recurrence was observed in one patient (4%). Conclusion: The necktie tightening of the vascular loop seton is a simple, safe, easily performed and may simplify the seton management of perianal fistulae.

RESUMO Setons para o tratamento de fístula perianal podem ser do tipo de corte ou do tipo frouxo. Adotamos uma técnica simples para apertar o seton, pela aplicação, na alça vascular, de uma laçada em forma de nó de gravata. Desse modo, inicialmente a laçada pode ser utilizada para drenagem e, subsequentemente, para as finalidades de corte. Neste estudo retrospectivo, relatamos nossa experiência com este método de aplicação da laçada do Seton em nó de gravata. Material e métodos: Foram revisados pacientes operados para fístula perianal entre 2012-2014. Resultados: Dos 63 pacientes operados, 23 (35%) receberam um Seton em nó de gravata. Desse total, 15 (65%) eram homens, com média de idade de 34,1 ± 10,6 anos. Seis (26%) tiveram fístula recorrente, e dois (9%) tiveram afrouxamento do seton in loco. Foram identificadas aberturas externas: anteriores, quatro (17%); laterais, 15 (65%); posteriores, três (13%); e duas aberturas em um paciente (4%). Também foram identificadas aberturas internas: posteriores, 17 (74%); anteriores, quatro (17%); e posteriores direitas, duas (8%). Em 19 (82%) havia um trato trans-esfinctérico, e quatro pacientes mulheres (17%) tiveram localização anterior. O tempo de cirurgia foi de 32 minutos (variação, 22-55). O seton foi apertado 4 vezes (variação, 2-5) a intervalos de 2 semanas. A cicatrização ocorreu em sete semanas (variação, 5-11). Ao longo dos 24 meses (variação, 12-35) de seguimento dos pacientes, não houve relato de incontinência anal. Houve recorrência em um paciente (4%). Conclusão: O aperto do Seton em alça vascular pela técnica do nó de gravata é método simples, seguro, de fácil realização e que pode simplificar o tratamento de fístulas perianais com Seton.

Manejo exitoso de infección de injerto vascular: rol del 18 fluorodeoxyglucose positron emission tomography/computed tomography / Successful management of vascular graft infection: The role of 18fluorodeoxyglucose positron emission tomography/computed tomography

La opción de un injerto vascular es una medida correctiva para pacientes con enfermedad arterial periférica o aneurismas y para acceso arteriovenoso en pacientes con hemodiálisis crónica. A partir de la colocación de una prótesis de injerto vascular se puede desarrollar infección asociada en el 1-6% de los pacientes, con una alta incidencia de mortalidad del 13 al 58%. El diagnóstico de una infección asociada a injerto vascular se realiza a partir de hallazgos clínicos, microbiológicos e imagenológicos, para así definir, además de su presencia, su compromiso y extensión. El manejo ideal requiere de tratamiento quirúrgico y antibioticoterapia; sin embargo, el tratamiento quirúrgico no siempre es posible. Reportamos este caso de manejo médico exitoso de una infección de injerto vascular de aorta en la cual el 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) presentó utilidad como método diagnóstico y de seguimiento.

The option of a vascular graft is a corrective intervention for patients with peripheral artery disease, aneurisms, and to achieve arterio-venous access in patients on chronic hemodialysis. Infections from a prosthetic vascular graft occurs in 1 to 6% of patients, and this development is related to the incidence of mortality of 13 to 58%. The diagnosis of a vascular graft infection is made via the combination of clinical, microbiologic and imaging findings that allow a definition of not only the presence of infection but also its severity and spread. The ideal approach requires both surgical and antimicrobial therapy; however, the former is not always possible. We report a case of successful medical management of an aortic vascular graft infection and the usefulness of a 18F-fluorodeoxyglucose positron emission tomography/computedtomography (18F-FDG-PET/CT) scan as a tool for diagnosis and follow-up.

Intraoperative analysis of flow dynamics in arteriovenous composite y grafts

Abstract Objective: Composite graft of left internal thoracic artery and great saphenous vein in revascularization of the left coronary system is a technique well described in literature. The aim of this study is to analyze blood flow dynamics in this configuration of composite graft especially in what concerns left internal thoracic artery's adaptability and influence of great saphenous vein segment on left internal thoracic artery's flow. Methods: Revascularization of left coronary system with composite graft, with left internal thoracic artery revascularizing the anterior interventricular artery and a great saphenous vein segment, anastomosed to the left internal thoracic artery, revascularizing another branch of the left coronary system, was performed in 23 patients. Blood flow was evaluated by transit time flowmetry in all segments of the composite graft (left internal thoracic artery proximal segment, left internal thoracic artery distal segment and great saphenous vein segment). Measures were performed in baseline condition and after dobutamine-induced stress, without and with non-traumatic temporary clamping of the distal segments of the composite graft. Results: Pharmacological stress resulted in increase of blood flow values in the analyzed segments (P<0.05). Non-traumatic temporary clamping of great saphenous vein segment did not result in statistically significant changes in the flow of left internal thoracic artery distal segment, both in baseline condition and under pharmacological stress. Similarly, non-traumatic temporary clamping of left internal thoracic artery distal segment did not result in statistically significant changes in great saphenous vein segment flow. Conclusion: Composite grafts with left internal thoracic artery and great saphenous vein for revascularization of left coronary system, resulted in blood flow dynamics with physiological adaptability, both at rest and after pharmacological stress, according to demand. Presence of great saphenous vein segment did not alter physiological blood flow dynamics in distal segment of left internal thoracic artery.

Incidencia de insuficiencia renal aguda posoperatoria en pacientes con aneurisma de aorta abdominal infrarrenal no roto: comparación entre abordaje abierto y endovascular / Incidence of postoperative acute renal insufficiency in patients with nonruptured abdominal aortic aneurysm: comparing open versus endovascular approaches

Introducción. La insuficiencia renal aguda es una complicación común después del reparo de un aneurisma infrarrenal de aorta abdominal; sin embargo, su incidencia es variable según el estudio y todavía existe controversia respecto a si es más frecuente en pacientes sometidos a reparación endovascular o a cirugía abierta. Objetivo. Determinar la incidencia de insuficiencia renal aguda posoperatoria en pacientes sometidos a corrección electiva por técnica abierta frente a la endovascular, de aneurisma de aorta abdominal infrarrenal no roto, en la Fundación Cardioinfantil-Instituto de Cardiología entre 2002 y 2014. Materiales y métodos. Se hizo un estudio de cohorte retrospectiva, que incluyó 326 pacientes con aneurisma de aorta infrarrenal no roto a los que se les practicó cirugía abierta (n=273) o reparación endovascular (n=53). Resultados. No existieron diferencias estadísticamente significativas entre la incidencia de insuficiencia renal aguda en el grupo con tratamiento abierto y aquella en el grupo con terapia endovascular (11 % Vs. 3,8 %) (p=0,1). El antecedente de infarto agudo de miocardio (odds ratio (OR)=4,21; IC95% 1,65-10,74; p=0,003) y de transfusión de glóbulos rojos (OR=2,65; IC95% 1,16-6,09; p=0,021), fueron los factores más importantes para desarrollar insuficiencia renal aguda. Conclusiones. No se evidencian diferencias estadísticas en el resultado de insuficiencia renal aguda posoperatoria según el tipo de abordaje. Sin embargo, el antecedente de infarto agudo de miocardio y la necesidad de transfusión en el posoperatorio están relacionados con la insuficiencia renal aguda.Palabras clave: aneurisma de la aorta abdominal; procedimientos quirúrgicos vasculares; procedimientos endovasculares; prótesis vascular; injerto vascular; insuficiencia renal.

Introduction: Acute renal failure is a common complication after elective repair of an infrarrenal aortic aneurysm; however, the incidence varies according to different studies. There is still controversy on whether it is more frequent in patients undergoing endovascular repair as opposed to open surgery.Objective: To determine the incidence of postoperative acute renal failure in patients with infrarenal abdominal aortic aneurysm undergoing elective repair by open technique versus endovascular repair at Fundación Cardioinfantil - Instituto de Cardiología (Bogotá, Colombia) in the period between 2002 and 2014.Method: We conducted a retrospective cohort study that included 326 patients with nomruptured infrarenal aortic aneurysm who underwent open surgery (n = 273) and endovascular repair (n = 53). Results: No statistically significant difference was found between the incidence of acute renal failure in the open treatment group and in the endovascular therapy group (11 % Vs 3.8%) (p 0.1), The history of acute myocardial infarction odds ratio (OR): 4.21; 95% CI 1.65- 10.74, p 0.003) and receiving red cells transfusion (OR: 2.65; 95% CI 1.16- 6.09, p 0.021) appeared as the most important risk factor for the development of acute renal failure. Conclusions: In this study we found that there is no difference in the outcome of postoperative acute renal failure comparing both techniques. However, previous myocardial infarction and the requirement of postoperative transfusion are associated with acute renal failure.

Effects of intraoperative diltiazem infusion on flow changes in arterial and venous grafts in coronary artery bypass graft surgery / Efeitos da infusão intraoperatória de diltiazem sobre as mudanças do fluxo em enxertos arteriais e venosos em cirurgia de revascularização do miocárdio

AbstractObjective:This study aimed to show the effects of intra-operative diltiazem infusion on flow in arterial and venous grafts in coronary artery bypass graft surgery.Methods:Hundred fourty patients with a total of 361 grafts [205 (57%) arterial and 156 (43%) venous] underwent isolated coronary surgery. All the grafts were measured by intraoperative transit time flow meter intra-operatively. Group A (n=70) consisted of patients who received diltiazem infusion (dose of 2.5 microgram/kg/min), and Group B (n=70) didn't receive diltiazem infusion.Results:Mean graft flow values of left internal mammary artery were 53 ml/min in Group A and 40 ml/min in Group B (P<0.001). Pulsatility index (PI) values of left internal mammary artery for Group A and Group B were 2.6 and 3.0 respectively (P<0.001). No statistically significant difference was found between venous graft parameters.Conclusion:We recommend an effect of diltiazem infusion in increasing graft flows in coronary artery bypass graft operations.

ResumoObjetivo:Este estudo teve como objetivo mostrar os efeitos da infusão de diltiazem intraoperatória no fluxo arterial e enxertos venosos em cirurgia de revascularização do miocárdio.Métodos:Cento e quarenta pacientes com um total de 361 enxertos [205 (57%) arteriais e 156 (43%) venosos] passaram por uma cirurgia coronária isolada. Todos os enxertos foram medidos pelo medidor de fluxo de tempo de trânsito intraoperatório. Grupo A (n=70), formado por pacientes que receberam infusão de diltiazem (dose de 2,5 micrograma/kg/min), e Grupo B (n=70), por aqueles que não receberam infusão de diltiazem.Resultados:Os valores médios de fluxo de enxerto de artéria mamária interna esquerda foram 53 ml/min no grupo A e 40 ml/min no Grupo B (P<0,001). Valores do índice de pulsatilidade da artéria mamária interna esquerda para o Grupo A e do Grupo B foram de 2,6 e 3,0, respectivamente (P<0,001). Não houve diferença estatisticamente significativa entre os parâmetros do enxerto venoso.Conclusão:Sugerimos um efeito da infusão de diltiazem em aumentar os fluxos de enxerto em operações de bypass de artéria coronária.

Early postoperative changes in hematological, erythrocyte aggregation and blood coagulation parameters after unilateral implantation of polytetrafluoroethylene vascular graft in the femoral artery of beagle dogs

PURPOSE: The failure of small-caliber vascular grafts still means a serious problem. Concerning the early postoperative complications we aimed to investigate the hemostaseological and hemorheological aspects of this issue in a canine model. METHODS: In the Control group only anesthesia was induced. In the Grafted group under general anesthesia a 3.5-cm segment was resected unilaterally from the femoral artery and replaced with a PTFE graft (diameter: 3 mm). On the 1st-3rd-5th-7th and 14th postoperative days the skin temperature of both hind limbs was measured, and blood sampling occurred for hematological, hemostaseological and hemorheological tests. RESULTS: The skin temperature of the operated versus intact limbs did not differ. In the Grafted group leukocyte count was elevated by the 1st postoperative day, while platelet count increased over the entire follow-up period. Fibrinogen concentration rose on the 1st-5th days, activated partial thromboplastin time increased on the 3rd-7th days. Erythrocyte aggregation was enhanced significantly on the 1st-5th days. In specimens taken on the 14th day, histologically we found matured thrombus narrowing the graft lumen. CONCLUSIONS: Small-caliber PTFE graft implantation into the femoral artery caused significant changes in several hemostaseological and hemorheological parameters. However, better clarifying the factors leading to early thrombosis of these grafts needs further studies. .

Transposition of cephalic vein to rescue hemodialysis access arteriovenous fistula and treat symptomatic central venous obstruction / Transposição de veia cefálica para salvamento de fístula arteriovenosa de hemodiálise e tratamento de obstrução venosa central sintomática

It is known that stenosis or central venous obstruction affects 20 to 50% of patients who undergo placement of catheters in central veins. For patients who are given hemodialysis via upper limbs, this problem causes debilitating symptoms and increases the risk of loss of hemodialysis access. We report an atypical case of treatment of a dialysis patient with multiple comorbidities, severe swelling and pain in the right upper limb (RUL), few alternative sites for hemodialysis vascular access, a functioning brachiobasilic fistula in the RUL and severe venous hypertension in the same limb, secondary to central vein occlusion of the internal jugular vein and right brachiocephalic trunk. The alternative surgical treatment chosen was to transpose the RUL cephalic vein, forming a venous necklace at the anterior cervical region, bypassing the site of venous occlusion. In order to achieve this, we dissected the cephalic vein in the right arm to its junction with the axillary vein, devalved the cephalic vein and anastomosed it to the contralateral external jugular vein, providing venous drainage to the RUL, alleviating symptoms of venous hypertension and preserving function of the brachiobasilic fistula.

Sabemos que estenose ou obstrução venosa central ocorre em 20 a 50% dos pacientes que são submetidos à colocação de cateter em veias centrais. Nos pacientes que realizam hemodiálise pelos membros superiores, este problema causa sintomas debilitantes e um grande risco de perda do acesso para hemodiálise. Relatamos um caso atípico de tratamento em um paciente dialítico com múltiplas comorbidades, queixa de dor e edema severo do membro superior direito (MSD), escassas alternativas de acessos vasculares para hemodiálise e fístula braquiobasílica funcionante do MSD associada à severa hipertensão venosa deste membro, secundária à oclusão venosa central da veia jugular interna e do tronco braquiocefálico direito. O tratamento cirúrgico alternativo foi a transposição da veia cefálica do MSD, formando colar venoso na região cervical anterior, resultando em um bypass sobre o sítio venoso ocluído. Para isso, realizamos a dissecção da veia cefálica no braço direito até a sua junção com a veia axilar, devalvulamos e anastomosamos a veia cefálica na veia jugular externa contralateral, permitindo a drenagem venosa do MSD, aliviando os sintomas da hipertensão venosa e mantendo a fístula braquiobasílica funcionante.

Estudo experimental comparativo de remendos arteriais de polidimetilsiloxano com reforço de tecido de poliéster (PDMSr) versus politetrafluoretileno expandido (PTFEe) em aorta de coelhos / Patch of polydimethylsiloxane reinforced with polyester fabric for aortic angioplasty in rabbits

Introdução: Apesar de bons resultados descritos na literatura, o substituto ideal para a utilização como remendo no fechamento arterial ainda não existe. Por este motivo, ainda há espaço para a busca por remendo que seja biocompatível, e que apresente facilidade de manuseio e resultados satisfatórios. Avaliamos remendos arteriais de silicone (polidimetilsiloxano com reforço em poliéster - PDMSr) em comparação com remendos arteriais de PTFEe. Objetivo: O objetivo deste trabalho é comparar, em modelo experimental, em coelhos, os resultados de remendos arteriais feitos em PDMSr com remendos de PTFEe. Materiais e Método: A amostra foi definida em 10 animais que completassem todas as etapas da pesquisa em cada grupo. Os animais foram submetidos à laparotomia mediana e abertura longitudinal da aorta de aproximadamente 8mm, realizando-se o seu fechamento com remendo do grupo selecionado, seguido do fechamento por planos. Os animais foram mantidos em biotério até o 60º PO, quando, então, realizou-se arteriografia de controle, e análise macro e microscópica de peça. Resultados: Para se atingir a amostra desejada, foram necessários 12 procedimentos no grupo PDMSr e 16 no grupo PTFEe. Ocorreram 2 óbitos no grupo PDMSr e 6 no grupo PTFEe. Apesar do número maior de óbitos no grupo PTFEe não houve diferença estatística na sobrevida entre os grupos. Um animal do grupo PDMSr apresentou monoparesia em pata posterior direita e um animal do grupo PTFEe apresentou hérnia incisional. Não houve diferença estatística nas complicações entre os grupos. O tempo operatório foi estatisticamente maior no grupo PTFEe quando comparamos todos os animais, fato que não se repetiu quando excluímos os animais que faleceram...

Introduction: Although good results are reported for various materials for use as patches for arterial closure, as yet none of these is ideal. Therefore, research is continuing into development of a patch that is biocompatible and provides ease of handling, while having satisfactory outcomes. A new silicone arterial patch (polydimethylsiloxane reinforced with polyester fabric, PDMSr) was compared with patches made of expanded polytetrafluoroethylene (ePTFE). Objective: To compare the outcomes between arterial patches made of PDMSr with those made of ePTFE, in an experimental rabbit model. Materials and Method: Rabbits were placed in two groups, and received either PDMSr or ePTFE arterial patches (PDMSr group and ePTFE group, respectively). The animals underwent laparotomy and longitudinal opening of the aorta, which was then closed with the selected patch, followed by suture of all layers. The animals were kept in their cages until the 60th postoperative day, when arteriography, removal of the aorta, and macroscopic and optic and scanning electron microscopic analyzes of the aorta were performed. Ten rabbits from each group that had completed all stages of the research were included in analyses. Results: Twelve procedures were performed in the PDMSr group and 16 in the ePTFE group. There were 2 deaths in the PDMSr group and 6 in the ePTFE group. Despite the higher number of deaths in the ePTFE group, there was no statistical difference in survival rate between the groups. One animal in the PDMSr group developed monoparesis in its right hind paw and 1 animal in the ePTFE group had an incisional hernia. There was no statistical difference in complications between the groups. The operative time was significantly longer in the ePTFE group when all animals were included in analysis, but not when animals that died were excluded...

Doppler echocardiographic criteria in patency assessment of composite grafts from left internal thoracic artery / Parâmetros Dopplerfluxométricos de perviedade do enxerto composto de artéria torácica interna esquerda

OBJECTIVES: The purpose of our study was to establish, with an entirely noninvasive method, transthoracic Doppler echocardiography, criteria for patency of composite left internal thoracic artery grafts when placed on the left anterior descending artery and other branches of the left coronary system. METHODS: The control group comprised 20 patients with single graft and 20 patients with composite graft; all forty having their patency confirmed by coronary angiogram (CA). In this control group, two Doppler echocardiographic variables, diastolic mean velocity-time and integral diastolic peak velocity to systolic peak velocity ratio were recorded. For each variable, established cut-off points were established, using the ROC (Receiver Operator Characteristic) curves, to identify criteria which could differentiate the composite grafts. Only patients with composite grafts were included in the 159-patients study group. The criteria established by the cut-off points in the control group were then applied to detect patency using a diastolic fraction of > 0.5 as the gold standard. The sensitivity, specificity, and positive and negative predictive values of these two criteria were determined. RESULTS: In the control group, cut-off points of 0.71 and 0.09m were established for the diastolic peak velocity/systolic peak velocity ratio and for diastolic mean velocity-time integral, respectively. In the study group phase, the sensitivity and negative predictive value of the diastolic peak velocity/systolic peak velocity > 0.71 criterion were 36% and 11%, respectively. Diastolic mean velocity-time integral > 0.09m criterion, were 40% and 10.48%. The specificities and positive predictive values of each criterion were 100%. CONCLUSION: Values reaching the criteria established for each variable indicate high probability of composite graft patency. Lower values have a large proportion of false negatives and are not conclusive as patency criteria.

OBJETIVO: O objetivo deste estudo é estabelecer parâmetros preditores de perviedade, avaliados por Dopplerfluxometria, do enxerto composto de artéria torácica interna esquerda, quando revasculariza a artéria interventricular anterior e outro ramo do sistema esquerdo. MÉTODOS: O grupo controle foi formado por 20 pacientes com enxerto simples e 20 pacientes com enxerto, composto cuja perviedade foi confirmada por cineangiocoronariografia. No grupo controle, as variáveis de fluxo relação velocidade pico diastólico/velocidade pico sistólico e integral da velocidade média/tempo na diástole foram registradas. Para cada variável, estabeleceram-se pontos de corte para identificar enxertos compostos, usando-se curvas ROC (receiver operator characteristic). No grupo estudo, foram avaliados 159 pacientes com enxerto composto, determinando-se os dois parâmetros de fluxo. Pontos de cortes estabelecidos no grupo controle foram usados para determinar sensibilidade, especificidade, valores preditivos positivo e negativo de cada variável relacionada à perviedade dos enxertos, tomando-se como referência a fração diastólica > 0,5. RESULTADOS: No grupo controle, os pontos de corte estabelecidos para as variáveis velocidade pico diastólico/velocidade pico sistólico e integral velocidade média/tempo na diástole foram, respectivamente, 0,71 e 0,09m. No grupo estudo, a sensibilidade para a velocidade pico diastólico/velocidade pico sistólico e integral da velocidade média/tempo na diástole, considerando seus pontos de corte, foi de 36,4% e 40%, respectivamente. Os respectivos valores preditivos negativos foram 11% e 10.48%, enquanto especificidade e valor preditivo positivo foram de 100% para os dois parâmetros. CONCLUSÃO: Valores maiores ou iguais aos estabelecidos para cada variável indicam alta probabilidade de perviedade do enxerto composto. Valores inferiores apresentam grande proporção de falsos negativos, não sendo conclusivos quanto à perviedade.

Relato de caso de tratamento endovascular de fístula aorto-entérica secundária / A case report of an endovascular treatment of secondary aortenteric fistula

O tratamento tradicional da fístula aorto-entérica secundária baseia-se na retirada cirúrgica da prótese, desbridamento aórtico, enxerto extra-anatômico, ou in situ, nos casos em que o campo cirúrgico apresenta-se sem sinais de infecção. Recentemente, alguns autores vêm preconizando o tratamento endovascular em pacientes instáveis e com alto risco cirúrgico. Apresentamos um relato de caso de paciente portador de fístula aorto-entérica secundária tratado inicialmente por via endovascular.

Traditional treatment of secondary aortoenteric fistula is based on open surgery followed by device removal, aortic debridement and extra-anatomic or in situ by-pass when no signs of local infection are found. Recently, some authors have been advocating endovascular treatment in unstable and high-risk patients. We present a case report of a patient who underwent initial endovascular treatment of a secondary aortoenteric fistula.

Achados de imagem da revascularização do miocárdio pela tomografia computadorizada por múltiplos detectores: onde estão os enxertos? Ensaio iconográfico / Imaging findings of myocardial revascularization at multidetector computed tomography: where are the bypass grafts? An iconographic essay

A angiotomografia por multidetectores de coronárias constitui um método preciso para avaliação dos enxertos venosos e arteriais pós-revascularização coronariana e vem substituindo em parte o cateterismo, o qual é um método invasivo e de maior custo. Este ensaio iconográfico tem como objetivo a demonstração anatômica dos enxertos mais comumente utilizados, como diferenciar enxertos venosos e arteriais e como localizá-los. Os exames foram realizados em aparelhos de tomografia computadorizada multislice de 64 fileiras de detectores, com apneia, frequência cardíaca controlada e protocolos adequados com posterior reconstruções MPR, MIP e 3D, de acordo com o eletrocardiograma. A localização dos enxertos e anastomoses em tomografias computadorizadas direcionadas para as artérias coronárias e para o tórax pode dificultar a análise do exame pelo radiologista não familiarizado, sendo que o conhecimento das técnicas cirúrgicas utilizadas e dos possíveis trajetos das pontes de safena e enxertos arteriais ajuda na análise de ambos os exames, evitando também erros diagnósticos.

Multidetector coronary computed tomography angiography is a precise method for evaluating post-coronary revascularization arterial and venous bypass grafts, and is somehow superseding coronary catheterization that is an invasive and more expensive technique. The present iconographic essay is aimed at anatomically demonstrating the bypass grafts most frequently utilized, how to differentiate between arterial and venous grafts and how to find them. The studies were performed in 64-row multidetector computed tomography equipment, with breath hold, controlled heart rate and appropriate protocols with later MPR, MIP and 3D reconstructions according to electrocardiogram. The localization of the bypass grafts and anastomoses at computed tomography studies focused on chest and coronary arteries may represent a difficulty in the images analysis by the radiologist who is not familiar with the matter, so the knowledge of the surgical techniques adopted and possible courses of the saphenous bypass grafts and arterial grafts can aid in the analysis of both studies, avoiding diagnostic errors.