Pool sanguíneo intramural aórtico. Presentación de un caso y revisión de la literatura / Aortic Blood Pool. Case Report and Review of the Literature

El hematoma intramural aórtico (HIM) forma parte del espectro del síndrome aórtico agudo. En el HIM se pueden presentar colecciones de medio de contraste conocidas en la literatura como "pool sanguíneo intramural" (PSIM) y "proyección similar a una úlcera" (PSU). El PSIM puede estar comunicado con ramas de la aorta o con la luz de la misma por un orificio intimal pequeño (1-2 mm). La PSU presenta una solución de continuidad intimal mayor de 3 mm de diámetro y, a diferencia de la úlcera aterosclerótica penetrante, no se acompaña de una placa ateroesclerótica. En general, la presencia de PSIM en pacientes con HIM aórtico no se asocia a mal pronóstico. Se presenta el caso de una paciente con dolor torácico y sospecha de disección aórtica, estudiada en nuestra institución con angiografía por tomografía computada, que demostró HIM y una colección de medio de contraste en el espesor del hematoma, interpretada como pool sanguíneo intramural. Se revisan las imágenes iniciales y el control con endoprótesis aórtica.

Aortic intramural hematoma (IMH) is part of the spectrum of acute aortic syndromes. Collections of contrast medium known in the literature as "intramural blood pool" (IMBP) and "ulcer-like projections" (ULP), may be present in the IMH. An IMBP could be connected with branches of the aorta or with the aortic lumen through a small tear in the intima (1-2 mm). The ULP represents a disruption of the intima greater than 3mm of diameter and unlike the penetrating atherosclerotic ulcer, this is not associated with an atherosclerotic plaque. In general, the presence of IMBP in patients with aortic IMH is not associated with poor prognosis. We present a case of a patient with chest pain and suspected aortic dissection, studied at our institution with CT angiography, which showed an IMH and a collection of contrast medium within the thickness of the hematoma, interpreted as an intramural blood pool. The initial images and control with aortic endograft are reviewed.

Engrosamiento nodular difuso de la pleura / Diffuse nodular thickening of the pleura

Paciente masculino de 52 años con dolor torácico de características pleuríticas y disnea de cuatro meses de evolución. La radiografía (imagen IA) y la tomografía computarizada (TC) de tórax (Figura IB), mostraron engrosamiento nodular difuso de la pleura y efusión pleural. El engrosamiento pleural se define por un espesor de la pleura > de 3 mm que puede ser focal o difuso. En la radiografía frontal se considera un engrosamiento pleural difuso a la alteración mayor de 25% de la superficie pleural (bilateral) o mayor de 50% (unilateral). En TC se puede considerar difuso al engrosamiento pleural con una longitud > 8 cm y un diámetro mayor de 5 cm . El engrosamiento del paciente: difuso, concéntrico y nodular sugiere enfermedad neoplásica (primaria o secundaria), principalmente: enfermedad metastásica, mesotelioma, linfoma y timoma invasivo. Ocasionalmente entidades infecciosas pueden presentar este hallazgo. La patología pleural del paciente confirmó mesotelioma maligno epitelioide. Este mesotelioma es más frecuente en personas entre la sexta y séptima década de la vida, predomina en hombres y se asocian a la exposición a asbestos.

Frecuencia de grupos sanguíneos ABO y Rh en donantes del banco de sangre del Hospital Pablo Tobón Uribe, entre 2000 y 2009, 50 años después del primer trabajo realizado en Medellín / Frequency of ABO and Rh blood group in blood bank donors of Hospital Pablo Tobon Uribe between 2000 and 2009, 50 years after the first report in Medellin

En 1964 se publicó en la revista Antioquia Médica el primer trabajo original sobre la frecuencia de grupos sanguíneos en Medellín, dirigido por el Dr. Alberto Restrepo Mesa, uno de los pioneros de la Hematología en Colombia; posteriormente se realizaron dos importantes trabajos en los años 1999 y 2006, sin embargo, no se cuenta con reportes actuales. Objetivo: Establecer la frecuencia de los grupos sanguíneos en Medellín y el Valle de Aburrá, después de 50 años de publicada la primera investigación. Metodología: Se realizó un estudio observacional descriptivo con una muestra de 87.000 personas adultas, de ambos sexos, sin discriminación racial, que donaron hemoderivados en el banco de sangre del Hospital Pablo Tobón Uribe de la ciudad de Medellín (Colombia), entre 2000 y 2009, y se calculó la frecuencia de los grupos sanguíneos ABO y Rh...

At 1964, Antioquia Medica journal published the first original work of blood type frequencies in Medellin led by Dr. Alberto Restrepo Mesa, one of Hematology pioneers in Colombia; later there have been two important investigations in 1999 and 2006, however, there are not current reports. Objective: Establish the blood type frequencies in Medellin and the Valle de Aburrá after 50 years of the first published investigation. Methods: An observational descriptive study was made, with a sample of 87.000 adult people of both sexes, without racial discrimination, who donated blood at the Hospital Pablo Tobón Uribe blood bank of Medellin (Colombia) between 2000 and 2009; and frequency of ABO and Rh blood groups was calculated...

Characterization of nCD64 expression in neutrophils and levels of s-TREM-1 and HMGB-1 in patients with suspected infection admitted in an emergency department / Caracterización de la expresión de nCD64 en neutrófilos y de los niveles de s-TREM-1 y HMGB-1 en pacientes con sospecha de infección admitidos en el departamento de emergencias

Introduction: The nCD64 receptor, the soluble triggering receptor expressed in myeloid cells (s-TREM-1), and the high mobility group-box 1 protein (HMGB-1) have been proposed as significant mediators in sepsis. Objective: To evaluate the prognostic value of these markers in patients with suspected infection recently admitted in an emergency department (ED). Materials and methods: All patients who presented to the ED with suspected infection were eligible for enrollment in this study. Baseline clinical data, Sequential Organ Failure Assessment score (SOFA) score, APACHE II score, HMGB-1 levels, s-TREM-1 levels, and nCD64 levels were analyzed. The HMGB-1 and sTREM-1 serum concentrations were determined using commercially available ELISA kits, and CD64 on the surface of neutrophils was measured by flow cytometry. Results:. A total of 579 patients with suspected infection as their admission diagnosis were enrolled in this study. The median patient age was 50 years (IQR = 35-68). Morbidity during the 28-day followup period was 11.1% (n=64). The most frequent diagnosis at the time of admission was communityacquired pneumonia (CAP) in 23% (n=133) patients, followed by soft tissue infection in 16.6% (n=96), and urinary tract infection in 15% (n=87). After multivariable analysis, no significant association was identified between any biomarker and 28-day mortality. Conclusion: In the context of a tertiary care hospital emergency department in a Latin-American city, the nCD64 receptor, s-TREM-1, and HMGB-1 biomarkers do not demonstrate prognostic utility in the management of patients with infection. The search continues for more reliable prognostic markers in the early stages of infection.

Introducción. El receptor CD64, receptor soluble ´desencadenador´ expresado en células mieloides (sTREM-1) y la proteína del grupo Box-1 de alta movilidad (HMGB-1), se han propuesto como mediadores en la sepsis. Objetivo. Evaluar el valor pronóstico de estos marcadores en pacientes con sospecha de infección, recientemente admitidos en un departamento de emergencias. Materiales y métodos. Se incluyeron en el estudio pacientes que consultaron al hospital con sospecha de infección. Se analizó la base de datos clínica, el puntaje SOFA, el puntaje APACHE II, los niveles de HMGB-1, los niveles de sTREM-1 y los niveles de nCD64. Se determinaron las concentraciones en suero de HMGB-1 y sTREM-1, usando kits de ELISA disponibles comercialmente, y la de CD64 se midió por citometría de flujo. Resultados. Se analizaron 579 pacientes con sospecha de infección al ingreso. La edad media fue de 50 años (rango intercuartílico=35-68), y 11,1 % (n=64) murieron durante el seguimiento de 28 días. El diagnóstico más frecuente en el momento del ingreso fue neumonía adquirida en la comunidad, en 23 % (n=133) de los pacientes, seguida de infección de tejidos blandos, en 16,6 % (n=96), e infección urinaria, en 15 % (n=87). Después de un análisis multivariado, no hubo asociación significativa entre ningún biomarcador y la mortalidad a los 28 días. Conclusión. Los resultados sugieren que en el contexto de un departamento de emergencias de tercer nivel de una ciudad latinoamericana típica, los tres marcadores evaluados no ofrecieron ninguna ventaja en el pronóstico de infección. La búsqueda de marcadores pronósticos más confiables en estadios tempranos de la infección aún continúa abierta.

Tratamiento de la enfermedad arterial periférica de las extremidades inferiores con células mononucleares de médula ósea autólogas: reporte de seguimiento a un año / Experience of autologous bone marrow mononuclear cells implantation as a treatment in patients with peripheral arterial disease: one year follow-up

Introducción: las células mononucleares de la médula ósea son efectivas para el tratamiento de pacientes con enfermedad arterial periférica (EAP). Los factores de crecimiento que ellas sintetizan se usan para inducir angiogénesis. Objetivo: establecer en Colombia la seguridad, factibilidad y resultado del tratamiento de la EAP utilizando células autólogas, para evitar su progreso a estadios más avanzados. Métodos: previo consentimiento, se hizo aspirado de médula ósea bajo anestesia local. Las células obtenidas se concentraron y se inyectaron intramuscularmente en los gastrocnemios de las extremidades isquémicas. El grupo control retrospectivo no recibió células. La evaluación clínica incluyó varios parámetros. Las células se analizaron por citometría de flujo. Resultados: edad media de los pacientes: 69 ± 11 años; viabilidad celular: 99,15% ± 0,76%; número de células inyectadas: 9,2 x 108 ± 6,2 x 108. Los análisis angiográficos postratamiento mostraron formación de vasos colaterales nuevos en las extremidades afectadas, con mínimo engrosamiento. Se observaron aumento en la distancia caminada libre de dolor y mejoría del dolor en reposo. La obtención y aplicación de las células no se asoció con ninguna complicación. Conclusiones: este estudio preliminar demostró que la terapia celular autóloga es segura, factible y cambia positivamente la historia natural de la EAP. Se sugiere el estudio de un número mayor de pacientes antes de establecer este tratamiento en Colombia.

Introduction: Autologous bone marrow mononuclear cells have been shown to be safe and effective for treatment of patients with peripheral arterial disease (PAD). Angiogenesis can also be induced by growth factors synthesized by them. Objective: To determine in Colombia the feasibility, safety and outcome of the afore-mentioned treatment. Methods: After informed consent, bone marrow was obtained by aspiration under local anesthesia; mononuclear cells were concentrated and their number and viability were established. They were suspended in saline solution and implanted by intramuscular injection into the gastrocnemius muscles of ischemic legs. Control patients were left untreated. Clinical evaluation included several parameters. Flow cytometry was used for cell analysis. Results: Mean age of patients: 69 ± 11 years; cell viability: 99.15 ± 0.76%; total number of injected cells: 9.2 x 108 ± 6.2 x 108. After treatment, angiographic studies showed the formation of new collateral vessels in all patients, with minimal thickness increase. There were no complications from bone marrow aspiration and intramuscular administration of cells. All treated patients experienced increase in the walking distance and improvement of rest pain. Conclusions: These preliminary results demonstrate that autologous cell therapy is safe, feasible and positively changes the natural history of patients with advanced peripheral arterial disease. In order to establish this treatment as a current practice in Colombia, we suggest the study of a larger number of patients.

Infección labial por citomegalovirus en un paciente infectado con VIH-1 / Labial cytomegalovirus infection in a patient infected with HIV-1

En pacientes infectados con el virus de la inmunodeficiencia humana tipo 1 (VIH-1), la infección por citomegalovirus (CMV) ocurre principalmente en estadios avanzados de la enfermedad, especialmente cuando el recuento de células T CD4+ en sangre periférica se encuentra por debajo de 100 células/mm3, lo cual favorece la progresión al sida y aumenta la probabilidad de muerte. El compromiso de la retina es la manifestación más común de esta coinfección, pero existen otras manifestaciones, como la radiculopatía periférica, la encefalopatía y el compromiso gastrointestinal; en raras ocasiones se observa neumonitis. Esta coinfección también puede presentarse como un cuadro fatal, asociado con una viremia alta y persistente, y con un compromiso grave de varios órganos. La infección cutánea por CMV es una manifestación muy rara en los pacientes positivos para VIH-1, la cual se observa cuando el recuento de células T CD4+ es menor de 50/mm3 y cursa con úlceras crónicas en la piel o las mucosas.Se presentan las características clínicas e inmunológicas de un caso de infección cutánea por CMV en un paciente positivo para VIH-1, y se revisa la literatura.

In patients infected with the type 1-human immunodeficiency virus (HIV-1), the cytomegalovirus (CMV) infection occurs mainly in advanced stages of the disease, especially when the CD4+ T-cell count in under 100 cells/millilitre, which accelerates the progression to AIDS and increases the risk of death. The retina compromise is the most frequent manifestation of the CMV infection associated to HIV-1. Other manifestations include peripheralpolyradiculopathy, encephalopathy, andgastrointestinal compromise. Pneumonitis is rarely observed. In addition, this coinfection can be presented as a fatal disease associated with high and persistent viremia and severe compromise of several organs. The cutaneous CMV infection is a very rare manifestation in HIV-1-infected patients, which is observed when the CD4+ T-cell count is under 50 cells/millilitre, and course with chronicskin and mucosal ulcers. We present the clinic and immunological characteristicsof an HIV-1-infected individual with aCMV cutaneous infection, making a comprehensive review of literature published.

Primera experiencia con las pruebas de ácidos nucleicos (NAAT) en donantes de sangre en Colombia / First experience with nucleic acid testing (NAAT) in blood donors in Colombia

Con el advenimiento de las pruebas moleculares de ácidos nucleicos (NAAT) a partir de 1998 para el virus de la hepatitis C (HCV), y posteriormente para el virus de la hepatitis B (HBV) y el virus de la inmunodeficiencia humana (HIV), se ha incrementado la seguridad relativa de la sangre comparada con las pruebas serológicas, y por tanto se ha reducido el período de ventana inmunológica...

Tratamiento de mordida abierta con dispositivos temporales de anclaje (DTA) / Open bite treatment with the use of TADS (Temporary anchorage device)

En este reporte de caso, un sistema de mini-implantes ortodóncicos vestibulares y palatinos, se utiliza para la intrusión de molares contribuyendo a la corrección de una mordida abierta dento-esquelética. Los aspectos tratados son: diagnóstico, tratamiento planteado, protocolo quirúrgico, consideraciones anatómicas, posibles complicaciones, curso del tratamiento, y presentación final del caso.

In this case report, a mini implant system that uses vestibular and palatal screws is presented as an excellent alternative for the treatment of and open bite case, it’s thru molar intrusion without any undesired transversal effect that the final results were achieved. The main topics treated are: diagnostic, treatment plan, surgical protocol, anatomic considerations, possible complications, curse of treatment, and final presentation of the case.

Cáncer de mama: HER2/neu, métodos diagnósticos y consideraciones clínicas / HER2/neu and Breast Cancer: Diagnosis and Clinical Issues

El cáncer de mama es una de las primeras causas de muerte de mujeres en el mundo. En Colombia, es la segunda causa de muerte de mujeres por cáncer, después del cáncer de cuello uterino. Aunque no se ha establecido una causa específica para el desarrollo del cáncer, se sabe que el cáncer de mama es el resultado de la acumulación de daños en el ácido desoxirribonucleico (DNA) de las células del tejido mamario. Se han identificado numerosos genes cuyas alteraciones afectan el crecimiento normal de la célula, llevándola al desarrollo y progresión del cáncer de mama. Uno de estos genes es el HER2/neu. La proteína codificada por el gen HER2/neu se encuentra sobreexpresada en un 25porciento-30porciento de los cánceres de mama; así, el HER2/neu es el oncogén de más alta incidencia en esta enfermedad. Actualmente, existen diferentes métodos moleculares paraidentificar la amplificación de este gen o la expresión de su producto. Aunque sólo dos de estos métodos diagnósticos (la inmunohistoquímica y la hibridación fluorescente in situ) se encuentran aprobados por la Administración de Drogas y Alimentos de los Estados Unidos (FDA), la reacción en cadena de la polimerasa en tiempo real y la hibridación cromogénica in situ prometen ser los métodos diagnósticos del futuro. La importancia clínica de medir la amplificación del gen HER2/neu radica en que la sobreexpresión de la proteína HER2/neu indica peor pronóstico y, por lo tanto, cambio de tratamiento, como el empleo del anticuerpo monoclonal humanizado trastuzumab.

Breast cancer is one of the first causes of death in women on the world. In Colombia it is the second cause of death in women with cancer after the carcinoma of cervix uteri. Although the specific cause is not known, it is know that breast cancer is the result of the accumulation of damages in the DNA of the cells of the mammary tissue. Numerous genes have been identified whose alterations affect the normal growth of the cell, taking it to the development and progression of the breast cancer. One of these genes it is the HER2/neu. The protein codified by HER2/neu gene, is overexpressed in 25% to 30% of the breast cancer, the HER2/neu is the oncogen of higher incidence in the disease. At the present time different molecular methods exist to identify the amplification of this gene or the expression of their product. Although only two of these diagnostic methods (the Immunohistochemistry and the fluorescence in situ hybridization) they are approved by the Administration of Drugs and Foods of the United States of America (FDA), the polymerase chain reaction in real time and the cromogenic in situ hybridization, not yet approved by the FDA, promise to be the methods to be used to in the future diagnoses, due to his high sensitivity, specificity, easy handling and low costs. The clinical importance to measure the amplification of the HER2/neu gene is in which overexpression of the HER2/neu protein indicates worse prognosis, and therefore the change of treatment, like the use of the monoclonal antibody humanized trastuzumab.

Utilidad del citoquímico y la coloración de Gram en muestras de orina en el diagnóstico de las infecciones del tracto urinario en pacientes hospitalizados / Usefulness of urinalysis and urine Gram stain in the diagnosis of urinary tract infection in hospitalized patients

OBJETIVO: evaluar la utilidad del citoquímico de orina y la coloración de Gram en el diagnóstico de la infección del tracto urinario en pacientes hospitalizados. DISEÑO Y MUESTRA: estudio de corte transversal; 10.917 urocultivos. MÉTODOS: se hicieron el citoquímico de orina y la coloración de Gram de la orina sin centrifugar según la solicitud de los médicos tratantes. Cuando no se solicitó este último examen, la coloración de Gram se hizo del sedimento urinario. Se compararon los resultados obtenidos con el resultado del urocultivo. Resultados: se obtuvo el resultado del citoquímico de orina en 6.762 de las muestras. Se solicitaron 2.762 coloraciones de Gram de orina sin centrifugar, y en 8.008 orinas se hizo la coloración de Gram del sedimento urinario. En comparación con el urocultivo, el citoquímico de orina presentó sensibilidad del 99%, especificidad del 51%, valor predictivo positivo del 60%, y valor predictivo negativo del 98%. La coloración de Gram de la orina sin centrifugar tuvo sensibilidad, especificidad y valores predictivos positivo y negativo de 98%, 73%, 82% y 97%, respectivamente. Para la coloración de Gram del sedimento urinario los valores correspondientes a la sensibilidad, especificidad y valores predictivos positivo y negativo fueron 95%, 78%, 67%, y 97%. CONCLUSIONES: el citoquímico de orina, bajo los criterios propuestos, y la coloración de Gram tienen un alto valor predictivo negativo, que permitiría utilizarlos como pruebas de tamización para determinar la necesidad de solicitar el urocultivo.

OBJECTIVE: To evaluate the usefulness of urinalysis and of urine Gram stain in the diagnosis of urinary tract infection in hospitalized patients. DESIGN AND SAMPLE: Urinalysis and Gram stain of non centrifuged urine were carried out according to the requests of physicians, in specimens submitted to the laboratory for urine culture. When this modality of Gram stain had not been requested, it was done with urine sediment. Results were compared with those of the culture. RESULTS: Ten thousand nine hundred and seventeen urine cultures were carried out, as well as 6.762 urinalyses, 2.762 Gram stains of non centrifuged urine, and 8.008 Gram stains of urine sediments. In comparison with the urine culture, urinalyses had 99% sensitivity, 51% specificity, 60% positive predictive value, and 98% negative predictive value. Gram stain of non centrifuged urine had 98% sensitivity, 73% specificity, 82% positive predictive value, and 97% negative predictive value. Gram stain of urine sediment had 95% sensitivity, 78% specificity, 67% positive predictive value, and 97% negative predictive value. CONCLUSIONS: Urinalysis, following well defined criteria, and Gram stain have high negative predictive values, that may allow to use them as screening tests to determine the need to request urine culture.

Interferência na reação de polimerização das siliconas de adição pelo contato direto ou indireto com luvas de látex / The interference in polimerization reaction of adittion silicones through direct or indirect contact with latex gloves

O objetivo deste estudo foi determinar quais marcas comerciais de luvas de látex apresentavam algum tipo de reação química impeditiva da polimerização completa das siliconas de adição (pasta densa e leve) pelo contato direto e indireto. Foi avalida a reação, de viscosidade leve e pesada, em contato direto com dez marcas comerciais de luvas de látex nacionais. A maior parte das luvas de látex testadas inibiu a polimerização da silicona de adição. Isso comprova que as siliconas de adição não devem entrar em contato com luvas de látex durante os procedimentos clínicos para evitar que sofram alterações das suas propriedades físico-químicas

Férulas de estabilização/placas de mordida / Oclusal bite-splint

Esta técnica aqui apresentada, demonstra a simplificação de um método para fabricação de uma placa oclusal estabilizadora, utilizando uma base de resina fotopolimerizável (Preci Tray Yeti), produzida pela Yeti Dentalprodulate, Industriosfrasse (Alemanha) e um aparelho fotopolimerizador para laboratório marca EDG. A maior vantagem desta técnica é a previsibilidade de sua pré-polimerização, pois permite resultados definitivos com relação ao trabalho final, já que é possível acrescentar fragmentos de resina ainda não ativados na matriz ou corpo principal da placa parcialmente fotopolimerizável.

Canulación de arteria axilar para circulación extracorpórea / Cannulation of axillary artery for extracorporeal circulation

Background: When the ascending aorta and the femoral artery cannot be used for extracorporeal circulation, an emerging alternative is the use of axillary artery. Aim: To report the experience using the axillary artery for extracorporeal circulation. Patients and methods: Between November 1998 and May 2002, 22 patients (14 male) were operated with extracorporeal circulation, cannulating the axillary artery. Briefly, an incision is made below the middle third of the clavicle and a cut is made on major pectoris muscle. Minor pectoris muscle is retracted and axillary artery is exposed. It is cannulated directly or with the aid of a prosthesis. Results: Right axillary artery was used in 21 patients and in 20 it was cannulated with the aid of a prosthesis. Mean flow was 4.5 + 0.6 l/min. The most common indications were aortic dissection or aneurysms. The most common procedures done, were ascending aorta replacement in 8 cases and replacement of ascending aorta and aortic arch in 5. Thirty five percent of operations were emergencies and 32 percent were reoperations. In 15 patients (68 percent), a circulatory arrest was done. Of these, retrograde brain perfusion was used in 9, antegrade brain perfusion through the same axillary artery was used in 2 and mixed perfusion was used in 2. One patient had a complication related to the axillary cannulation. None had cerebrovascular accidents or thromboembolic complications. Two patients died in the postoperative period. Patients were followed up to 42 months after the procedure and no secondary complications of the cannulation were detected. Conclusions: When the ascending aorta and the femoral artery cannot be used, axillary artery is a good alternative for extracorporeal circulation

Operación de Fontan: resultados inmediatos y a mediano plazo con anastomosis cavopulmonar total / Fontan procedure: early and mid-term results wiht total cavopulmonary anastomosis

Background: During the last five years, 65 patients with univentricular heart have been treated surgically in our institution, according to a protocol of staged operations that have been previously reported. Aim: To evaluate the early and mid-term outcome of those patients that have completed their staging protocol by means of a Fontan procedure. Patients and Methods: Between April 1996 and June 2001, 23 patients (age 16 to 223 months) underwent a Fontan procedure, 15 with an intracardiac lateral tunnel technique and 8 with an extracardiac conduit. A retrospective review of their clinical, surgical, echocardiographic, angiographic and hemodynamic data was performed, trying to identify risk factors for both mortality and functional capacity (FC). Follow up was complete in all survivors. Results: Three patients died early after surgery (13.04 percent). Excessive pulmonary blood flow was a risk factor for early death (p= 0.03). One patient died at 14 months. Follow up was 29.9 months (1-63). For those who survived the operation, five years survival was 93.3 percent. The majority of patients are in FC I or II, with no related risk factors. Conclusions: Our current results are comparable with those of larger series. Patients reach good FC and mid-term survival, irrespective of type of single ventricle or the surgical strategy

Consideraçöes morfológicas sobre a preparaçäo de dentes pilares em prótese fixa / Morphology approach to tooth preparation in fixes prosthodontics

O diagnóstico perceptivo realizado pelo odontológo e a qualidade da preparaçäo dentária predeterminam a longevidade da maioria das próteses fixas. Procedimentos em próteses fixas biologicamente toleráveis iniciam-se pela preparaçäo dentária. Os princípios biomecânicos da preparaçäo dentária e sua relaçäo com a morfologia dos dentes são aqui discutidos

Tratamiento quirúrgico de la coartación aótica en recién nacidos y lactantes menores de tres meses / Surgical treatment of the aortic coarctaction in newborn and infants under 3 months old

Antecendentes: La cirugía es el tratamiento de elección de la coartación aórtica. Sus resultados deben evaluarse no sólo en base de morbimortalidad operatoria si no también en relación a la incidencia de coartación residual y recoartación, hecho que es más frecuente en recién nacidos. Actualmente, dado el interés progresivo en la angioplastia primaria como tratamiento de esta patología se hace necesario conocer los resultados actuales del tratamiento quirúrgico. Objetivo: Analizar y reportar nuestra experiencia en el subgrupo de pacientes de mayor riesgo. Método: Se analizaron retrospectivamente todos los pacientes de hasta 3 meses de edad (menores de 120 días) sometidos a cirugía de coartación aórtica en nuestra institución, entre enero de 1989 y agosto de 1999. Se efectuó un análisis descriptivo de las características generales y de la técnica quirúrgica, así como de los resultados inmediatos y alejados. Resultados: Cincuenta y nueve pacientes fueron sometidos a reparación quirúrgica de la coartación aótica. La edad fue de 35ñ33 días, correspondiendo un 57 por ciento a recién nacidos. Treinta y seis pacientes (61 por ciento) eran del sexo masculino. El peso fue de 3.650ñ1.057 g. La coartación aótica se presentó en forma aislada en 28 pacientes (47,5 por ciento), asociada a CIV en 7 (11,9 por ciento) y a otra patología intracardíaca en 24 (40,7 por ciento). Treinta y seis pacientes (61 por ciento) presentaron unarco aórtico normal, 17 hipoplasia del istmo (28,8 por ciento) y 6 hipoplasia del arco transverso (10 por ciento). La principal indicación de cirugía fue insuficiencia cardíaca. Al momento de la cirugía 17 pacientes (31,5 por ciento) se encontraban en ventilación mecánica y 20 (37 por ciento) habían recibido de protaglandinas. La técnica quirúrgica fue: anastomosis término-terminal en 31 (52,5 por ciento); anastomosis término-terminal extendida en 24 (40,7 por ciento) y colgajo subclavio en 4 (6,7 por ciento). El tiempo de clampeo aórtico fue de tomosis fue de 18,4ñ6,2 minutos. En siete pacientes (11.9 por ciento) se efectuó cirugía cardíaca adicional. Cuatro pacientes (6,7 por ciento) presentaron coartación aórtica residual la cual motivó cirugía en un caso (1,7 por ciento) y angioplastia en otro. Ningún paciente presentó paraplejia. La mortalidad quirúrgica a 30 días fue de 3,4 por ciento (2 casos). Siete pacientes (11,8 por ciento) fallecieron durante el seguimiento, obteniéndose una sobrevida actuarial a 5 años de 83,9 por ciento

Experiencia de 36 años con marcapasos implantables: un análisis histórico / A 36 year experience with implantable pacemakers

Background: The implantation of pacemakers improves cardiac function and quality of life, in particular with dual chamber DDD and DDDR modes. Aim: To evaluate our clinical experience and results on pacemaker implantation, from 1963 to 1998. Material and methods: Computerized data collected from 2,445 consecutive paced patients was reviewed. A total of 3,554 operative procedures were performed, including 412 procedures for complications and 697 pacemaker replacement. Patient survival was determined from clinical records, inquiry to pacemaker manufacturers and death certificates from Servicio de Registro Civil e Identificaci-n de Chile (Chilean Civil and Identification Registry). Results: Use of dual chamber (DDD and DDDR) pacemakers increased progressively up to 74 percent from 1988 to 1998. Complication rate was 42 percent in the 1963-1976 study period, it decreased to 10.6 percent in the 1977-1987 study period, and to 5.6 percent by 1988-1998. Only two patients died during surgery in the study period (0.08 percent). In the 1977-1987 period, pacemakers lasted 10.6 years. Survival rates were 52 percent at ten years, 33 percent at 15 years, and 21 percent at 20 years, with a median survival of 11.7 years, and 7.24 years in patients over 80 years old. Conclusions: Transvenous permanent pacing can be accomplished today with a low complication rate, mainly due to better technology and surgical procedures

Cirugía de la insuficiencia mitral isquémica / Surgery for ischemic mitral regurgitation

Background. Ischemic mitral regurgitation (IMR) is a severe condition which may be best treated by surgery, nowithstanding a relatively high mortality rate. Objectives. To evaluate the results of mitral valve replacement or repair in patients with IMR. Patients and methods. Retrospective review of the clinical records in 29 patients with IMR who were surgically treated from 1990 to 1999. They represent 8 percent of surgical procedures on the mitral valve. Results. Mean age was 67 ñ 9 years. Surgery was performed urgently in 19 patients (66,5 percent). NYHA functional class was 3.4 ñ 0.8. The mechanism of IMR was annular dilatation and spreading of papillary muscles in 18 patients, papillary muscle rupture in 9 and fibrosis in 2. Mitral valve replacement was performed in 14 patients and mitral valve repair in 15. Twenty four patients (83 percent) had concomitant myocardial revascularization. Overall surgical mortality was 24 percent; 26 percent for mitral replacement and 13 percent for mitral valve repair (p=0.215). On follow up of 26ñ33 months, one year survival was 76ñ0.8 percent and 5 years survival was 59ñ12 percent. Excluding in hospital mortality, survival was 100 percent at one year and 78ñ14 percent at 5 years. Functional class improved in all survivors, to 1.4ñ0.5. Late echocardiographic evaluation of patients with mitral valve repair showed absence of mitral regurgitation in 58 percent, 1+ MR in 17 percent and 2+ MR in 25 percent. Conclusion. In spite of a high perioperative mortality, surgery for IMR is a valuable procedure for patients with an otherwise highly lethal disease

Reoperaciones coronarias: análisis retrospectivo de 16 años de experiencia / Coronary artery bypass grafting reoperation: a 16 years retrospective analysis

Background: Coronary artery bypass grafting (CABG) reoperation is being performed with increasing frequency. Aim: To assess the early and long term results of coronary reoperations in our institution and to identify prognostic factors. Patients and methods: 214 patients subjected to coronary reoperations between 1983 and 1999 were retrospectively studied. Results: Mean age was 64.2 years (range 42-79 years), 202 (94.4 per cent) were male and 12 (5.6 per cent) female. The mean interval between the operations was 125.7 months (range 6-252 months). 10 (4,6 per cent) were emergency surgeries. Overall operative mortality was 5.6 per cent (11 deaths) and in 5 patients (3.4 per cent) a perioperative myocardial infarction was noted. Univariate analysis identified moderate or severe left ventricular failure (p=0.048) as predictor of increased operative mortality, meanwhile age over 75 years (p=0.02) and moderate or severe left ventricular failure (p=0.01) were identified as predictors of increased in hospital mortality in the multivariate analysis. Follow up of in hospital survivors (mean interval 65 months, range 4 to 190 months) documented a 5 years survival rate of 82.9 per cent, a 10 years survival rate of 73.1 per cent and a 15 years survival rate of 53.4 per cent. Moderate or severe left ventricular failure (p <0.0001) and emergency surgeries (p=0.007) were identified as factors influencing the late survival in the stepwise logistical regression analysis. Multivariate analysis identified left ventricular failure (p=0.01) and peripheral vascular disease (p=0.01) as predictors of decreased late survival. Conclusions: Coronary reoperation has a low mortality in patients with a normal ventricular function and also has an excellent overall and disease free survival in the first 10 years of follow up. Left ventricular function is an independent risk factor increasing in hospital and late mortality

Tratamiento de la insuficiencia cardíaca avanzada mediante trasplante de corazón / Heart transplantation as a treatment for advanced heart failure

Background: Heart transplantation currently provides the most effective treatment for advanced heart failure. However, medical therapy for this condition has also improved, heart donors are scarce and the cost of the procedure is high. Therefore the indications and management of these patients need reevaluation. Aim: To analyze the results of 24 patients submitted to heart transplantation for end-stage heart failure needing repeated hospitalizations and i.v. inotropes for compensation. Patients and methods: The group was comprised by 21 men and 3 women with a mean age of 36.8 years, mean left ventricular ejection fraction 19ñ4.5 percent, mean systolic pulmonary artery pressure 48ñ13 mmHg (24-70) and mean pulmonary vascular resistance 2.6 Wood Units (1-5). Fourteen patients (58 percent) had a previous median sternotomy. Immunosupression did not include induction therapy and steroids were discontinued early...