ABSTRACT This study investigates the relation between the types of collateral offered in rural loans in Brazil and the access to credit, loan conditions and default rates. We use a novel proprietary database of rural loans granted by one of the largest private banks in Brazil containing more than 110 thousand loan observations. Our results show that the use of fiduciary lien, improves the access to loans for more opaque borrowers (i.e., those with shorter relationship with the bank). This type of collateral gives the bank the ability to seize collateral quicker, reducing loss given default, even if these borrowers are riskier, given that they present higher default rates on average. Our results also show that loan conditions are less restrictive as relationship length increases, and that this effect is more intense among loans collateralized by fiduciary lien.

RESUMEN Este estudio investiga la relación entre los tipos de garantía ofrecidos en los préstamos a los productores rurales en Brasil, el acceso al crédito, las condiciones del préstamo y el incumplimiento. Utilizamos una base de datos propietaria e inédita de crédito rural de un gran banco privado hrasileno con más de 110 mil observaciones de préstamos. Los resultados muestran que el uso de la alienación fiduciaria permite a los prestatarios más opacos (es decir, con menor tiempo de relación con el banco) acceder al crédito. Ese tipo de garantía le da al banco la capacidad de recuperar el activo más rápidamente reduciendo la pérdida en caso de impago, incluso si esos prestatarios son más riesgosos, ya que presentan mayores tasas de incumplimiento. Nuestros resultados también muestran que las condiciones de los préstamos son menos restrictivas a medida que aumenta la duración de la relación bancaria, y que este efecto es más intenso en los préstamos con alienación fiduciaria.

RESUMO Este estudo investiga a relação entre os tipos de garantia oferecidos em empréstimos ao produtor rural no Brasil e o acesso, as condições de crédito e a inadimplência. Usamos uma base de dados proprietária e inédita de crédito rural de um grande banco privado brasileiro com mais de 110 mil observações de empréstimos. Os resultados apontam que o uso da alienação fiduciária permite que tomadores mais opacos (i.e., com menor tempo de relacionamento com o banco) consigam acesso a crédito. Esse tipo jurídico de garantia dá ao banco a capacidade de retomar o ativo mais rapidamente, reduzindo a perda em caso de inadimplência, mesmo que os tomadores sejam mais arriscados, uma vez que apresentam maiores taxas de inadimplência (default). Nossos resultados mostram que as condições dos empréstimos são menos restritivas com o aumento do tempo de relacionamento bancário, e que esse efeito é mais intenso nos empréstimos com alienação fiduciária.

Abstract Objectives: This study sought to evaluate the impact of prosthesis-patient mismatch (PPM) on the risk of early-term mortality after transcatheter aortic valve implantation (TAVI). Methods: Databases (Medical Literature Analysis and Retrieval System Online [MEDLINE], Excerpta Medica dataBASE [EMBASE], Cochrane Controlled Trials Register [CENTRAL/CCTR], ClinicalTrials.gov, Scientific Electronic Library Online [SciELO], Latin American and Caribbean Literature on Health Sciences [LILACS], and Google Scholar) were searched for studies published until February 2019. PPM after TAVI was defined as moderate if the indexed effective orifice area (iEOA) was between 0.85 cm2/m2 and 0.65 cm2/m2 and as severe if iEOA ≤ 0.65 cm2/m2. Results: The search yielded 1,092 studies for inclusion. Of these, 18 articles were analyzed, and their data extracted. The total number of patients included who underwent TAVI was 71,106. The incidence of PPM after TAVI was 36.3% (25,846 with PPM and 45,260 without PPM). One-year mortality was not increased in patients with any PPM (odds ratio [OR] 1.021, 95% confidence interval [CI] 0.979-1.065, P=0.338) neither in those with moderate PPM (OR 0.980, 95% CI 0.933-1.029, P=0.423). Severe PPM was separately associated with high risk (OR 1.109, 95% CI 1.041-1.181, P=0.001). Conclusion: The presence of severe PPM after TAVI increased early-term mortality. Although moderate PPM seemed harmless, the findings of this study cannot not rule out the possibility of it being detrimental, since there are other registries that did not address this issue yet.

Abstract Prosthesis-patient mismatch (PPM) after surgical aortic valve replacement (SAVR) is an issue that has been overlooked (not to say neglected). Cardiac surgeons must bear in mind that this is a real problem that we must tackle. The purpose of this paper is to be a wake-up call to the surgical community by giving a brief overview of what PPM is, its incidence and impact on the outcomes. We also discuss the increasing role played by imaging for predicting and assessing PPM after SAVR (with which surgeons must become more acquainted) and, finally, we present some options to avoid PPM after the surgical procedure.

Abstract Objective: This study sought to evaluate the impact of prosthesis-patient mismatch on the risk of perioperative and long-term mortality after mitral valve replacement. Methods: Databases were researched for studies published until December 2018. Main outcomes of interest were perioperative and 10-year mortality and echocardiographic parameters. Results: The research yielded 2,985 studies for inclusion. Of these, 16 articles were analyzed, and their data extracted. The total number of patients included was 10,239, who underwent mitral valve replacement. The incidence of prosthesis-patient mismatch after mitral valve replacement was 53.7% (5,499 with prosthesis-patient mismatch and 4,740 without prosthesis-patient mismatch). Perioperative (OR 1.519; 95%CI 1.194-1.931, P<0.001) and 10-year (OR 1.515; 95%CI 1.280-1.795, P<0.001) mortality was increased in patients with prosthesis-patient mismatch. Patients with prosthesis-patient mismatch after mitral valve replacement had higher systolic pulmonary artery pressure and transprosthethic gradient and lower indexed effective orifice area and left ventricle ejection fraction. Conclusion: Prosthesis-patient mismatch increases perioperative and long-term mortality. Prosthesis-patient mismatch is also associated with pulmonary hypertension and depressed left ventricle systolic function. The findings of this study support the implementation of surgical strategies to prevent prosthesis-patient mismatch in order to decrease mortality rates.

Abstract The best treatment for patients with ischemic heart failure (HF) is still on debate. There is growing evidence that coronary artery bypass graft (CABG) benefits these patients. The current recommendations for revascularization in this context are that CABG is reasonable when it comes to decreasing morbidity and mortality rates for patients with severe left ventricular dysfunction (ejection fraction <35%), and significant coronary artery disease (CAD) and should be considered in patients with operable coronary anatomy, regardless whether or not there is a viable myocardium (class IIb). Percutaneous coronary intervention (PCI) does not have enough data to allow the panels to reach a conclusion. The Korean Acute Heart Failure registry (KorAHF) had its data released recently, showing that patients with acute HF who underwent CABG had lower death rates, more complete revascularization and less adverse outcomes compared with patients treated with PCI. Recent ESC/EACTS guidelines on myocardial revascularization clearly recommended CABG as the first choice of revascularization strategy in patients with multivessel disease and acceptable surgical risk to improve prognosis in this scenario of left ventricular dysfunction. However, a high peri-procedural risk must be compared with the benefit of late mortality, and pros and cons of each strategy (either PCI or CABG) must be weighed in the decision-making process. Spurred on by the publication of the above-mentioned article and the release of new guidelines, we went on to write an overview of the current practice of state-of-the-art coronary revascularization options in patients with HF.

Abstract Objective: We aimed to analyze whether patent foramen ovale (PFO) closure reduces the risk of stroke, assessing also some safety outcomes after the publication of a new trial. Introduction: The clinical benefit of closing a PFO has been an open question, so it is necessary to review the current state of published medical data in regards to this subject. Methods: MEDLINE, EMBASE, CENTRAL/CCTR, SciELO, LILACS, Google Scholar and reference lists of relevant articles were used to search for randomized controlled trials (RCTs) that reported any of the following outcomes: stroke, death, major bleeding or atrial fibrillation. Six studies fulfilled our eligibility criteria and included 3560 patients (1889 for PFO closure and 1671 for medical therapy. Results: The risk ration (RR) for stroke in the “closure” group compared with the “medical therapy” showed a statistically significant difference between the groups, favouring the “closure” group (RR 0.366; 95%CI 0.171–0.782, P=0.010). There was no statistically significant difference between the groups regarding the safety outcomes, death and major bleeding, but we observed an increase in the risk of atrial fibrillation in the “closure” group (RR 4.131; 95%CI 2.293–7.443, P<0.001). We also observed that the larger the proportion of effective closure, the lower the risk of stroke. Conclusion: This meta-analysis found that stroke rates are lower with percutaneously implanted device closure than with medical therapy alone, being these rates modulated by the rates of hypertension, atrial septal aneurysm and effective closure. The publication of a new trial did not change the scenario in the medical literature.

Abstract Objective: We aimed to determine whether patent foramen ovale closure reduces the risk of stroke, also assessing some safety outcomes. Introduction: The clinical benefit of closing a patent foramen ovale after a cryptogenic stroke has been an open question for several decades, so that it is necessary to review the current state of published medical data in this regard. Methods: MEDLINE, EMBASE, CENTRAL/CCTR, SciELO, LI-LACS, Google Scholar and reference lists of relevant articles were searched for randomized controlled trials that reported any of the following outcomes: stroke, death, major bleeding or atrial fibrillation. Five studies fulfilled our eligibility criteria and included 3440 patients (1829 for patent foramen ovale closure and 1611 for medical therapy). Results: The risk ratio (RR) for stroke in the "device closure" group compared with the "medical therapy" showed a statistically significant difference between the groups, favouring the "device closure" group (RR 0.400; 95% CI 0.183-0.873, P=0.021). There was no statistically significant difference between the groups regarding the safety outcomes death and major bleeding, but we observed an increase in the risk of atrial fibrillation in the "device closure group (RR 4.000; 95% CI 2.262-7.092, P<0.001). We also observed that the larger the proportion of effective closure, the lower the risk of stroke. Conclusion: This meta-analysis found that stroke rates are lower with percutaneously implanted device closure than with medical therapy alone, being these rates modulated by the rates of effective closure.

Abstract Objective: To compare the safety and efficacy of coronary artery bypass grafting (CABG) with percutaneous coronary intervention (PCI) using drug-eluting stents (DES) in patients with unprotected left main coronary artery (ULMCA) disease. Methods: MEDLINE, EMBASE, CENTRAL/CCTR, SciELO, LILACS, Google Scholar and reference lists of relevant articles were searched for clinical studies that reported outcomes at 1-year follow-up after PCI with DES and CABG for the treatment of ULMCA stenosis. Five studies fulfilled our eligibility criteria and they included a total of 4.595 patients (2.298 for CABG and 2.297 for PCI with DES). Results: At 1-year follow-up, there was no significant difference between CABG and DES groups concerning the risk for death (risk ratio [RR] 0.973, P=0.830), myocardial infarction (RR 0.694, P=0.148), stroke (RR 1.224, P=0.598), and major adverse cerebrovascular and cardiovascular events (RR 0.948, P=0.680). The risk for target vessel revascularization (TVR) was significantly lower in the CABG group compared to the DES group (RR 0.583, P<0.001). It was observed no publication bias regarding the outcomes, but only the outcome TVR was free from substantial statistical heterogeneity of the effects. In the meta-regression, there was evidence that the factor "female gender" modulated the effect regarding myocardial infarction rates, favoring the CABG strategy. Conclusion: CABG surgery remains the best option of treatment for patients with ULMCA disease, with lower TVR rates.

Em 2009, o Programa Nacional de Controle da Tuberculose recomendou a mudança do regime para o tratamento da tuberculose sensível. As mudanças consistiram na inclusão do etambutol, a redução das dosagens de isoniazida e pirazinamida e a modificação da formulação de cápsula para comprimido em dose fixa combinada. O processo de mudança foi viabilizado por apoio técnico, político e financeiro, que garantiu o abastecimento interno e o treinamento dos profissionais de saúde. A presente análise do caso brasileiro permitiu elencar lições aprendidas com o processo e formular recomendações para a sustentabilidade desta e de futuras inovações tecnológicas no diagnóstico, prevenção e tratamento da tuberculose.

In 2009, the Brazilian National Tuberculosis Program recommended changing the regimen for the treatment of sensitive tuberculosis by replacing RHZE with RHZ, involving reduced doses of isoniazid and pyrazinamide in a fixed-dose combination formulation. The process of change was made possible by the financial, political and technical support that ensured national drug provision and the training of healthcare professionals. In this analysis of the Brazilian case, we present the lessons learned with the implementation process and we formulate recommendations for the sustainability of this and other future technological innovations in the diagnosis, prevention and treatment of tuberculosis.

En 2009, el Programa Nacional de Control de la Tuberculosis recomendó el cambio de régimen para el tratamiento de la tuberculosis sensible. Los cambios consistieron en la inclusión del etambutol, la reducción de las dosis de isoniazida y pirazinamida y la modificación de la formulación de cápsula para comprimido a dosis fija combinada. El proceso de cambio fue viable por el gracias al apoyo técnico, político y financiero, que garantizó el abastecimiento interno y la capacitación de los profesionales de salud. El presente análisis del caso brasileño permitió registrar las lecciones aprendidas con el proceso y formular recomendaciones para la sustentabilidad de esta y de futuras innovaciones tecnológicas en el diagnóstico, prevención y tratamiento de la tuberculosis.

Em 2009, o Programa Nacional de Controle da Tuberculose recomendou a mudança do regime para o tratamento da tuberculose sensível. As mudanças consistiram na inclusão do etambutol, a redução das dosagens de isoniazida e pirazinamida e a modificação da formulação de cápsula para comprimido em dose fixa combinada. O processo de mudança foi viabilizado por apoio técnico, político e financeiro, que garantiu o abastecimento interno e o treinamento dos profissionais de saúde. A presente análise do caso brasileiro permitiu elencar lições aprendidas com o processo e formular recomendações para a sustentabilidade desta e de futuras inovações tecnológicas no diagnóstico, prevenção e tratamento da tuberculose.

In 2009, the Brazilian National Tuberculosis Program recommended changing the regimen for the treatment of sensitive tuberculosis by replacing RHZE with RHZ, involving reduced doses of isoniazid and pyrazinamide in a fixed-dose combination formulation. The process of change was made possible by the financial, political and technical support that ensured national drug provision and the training of healthcare professionals. In this analysis of the Brazilian case, we present the lessons learned with the implementation process and we formulate recommendations for the sustainability of this and other future technological innovations in the diagnosis, prevention and treatment of tuberculosis.

En 2009, el Programa Nacional de Control de la Tuberculosis recomendó el cambio de régimen para el tratamiento de la tuberculosis sensible. Los cambios consistieron en la inclusión del etambutol, la reducción de las dosis de isoniazida y pirazinamida y la modificación de la formulación de cápsula para comprimido a dosis fija combinada. El proceso de cambio fue viable por el gracias al apoyo técnico, político y financiero, que garantizó el abastecimiento interno y la capacitación de los profesionales de salud. El presente análisis del caso brasileño permitió registrar las lecciones aprendidas con el proceso y formular recomendaciones para la sustentabilidad de esta y de futuras innovaciones tecnológicas en el diagnóstico, prevención y tratamiento de la tuberculosis.

Problem The World Health Organization has endorsed the Xpert MTB/RIF (Xpert), an automated polymerase-chain-reaction-based assay, for the rapid diagnosis of tuberculosis. However, large-scale use of a new technology calls for preparation and adaptation. Approach A pilot implementation study was conducted in two Brazilian cities to explore the replacement of sputum smear microscopy with Xpert. The laboratories included covered 70% of the tuberculosis cases diagnosed, had no overlap in population catchment areas, handled different workloads and were randomly shifted to Xpert. Sputum samples were collected through the same routine procedures. Before the study the medical information system was prepared for the recording of Xpert results. Laboratory technicians were trained to operate Xpert machines and health workers were taught how to interpret the results. Local setting The average annual tuberculosis incidence in Brazil is around 90 cases per 100 000 population. However, co-infection with the human immunodeficiency virus and multidrug resistance are relatively infrequent (10% and < 2%, respectively). Relevant changes Of the tested sputum samples, 7.3% were too scanty for Xpert and had to be examined microscopically. Ten per cent of Xpert equipment needed replacement, but spare parts were not readily available in the country. Absence of patient identification numbers led to the introduction of errors in the medical information system. Lessons learnt For nationwide scale-up, a local service provider is needed to maintain the Xpert system. Ensuring cartridge availability is also essential. The capacity to perform smear microscopy should be retained. The medical information system needs updating to allow efficient use of Xpert.

Resumen Situación La Organización Mundial de la Salud ha aprobado Xpert MTB/RIF (Xpert), un ensayo automatizado basado en la reacción en cadena de la polimerasa para el diagnóstico rápido de la tuberculosis (TB). Sin embargo, el uso a gran escala de una tecnología nueva requiere una preparación y adaptación. Enfoque Con objeto de examinar la sustitución de la microscopia de frotis de esputo con Xpert, se llevó a cabo un estudio piloto de implementación en dos ciudades brasileñas. Los laboratorios participantes incluyeron el 70 % de los casos de tuberculosis diagnosticados, no se produjo ningún solapamiento en las zonas de captación de población, manejaron cargas de trabajo distintas y se asignaron a Xpert de forma aleatoria. Las muestras de esputo se recogieron a través de los mismos procedimientos rutinarios. Antes del estudio, se preparó el sistema de información médica con objeto de registrar los resultados de Xpert. Se capacitó a los técnicos de laboratorio para operar máquinas Xpert y se enseñó a los trabajadores sanitarios cómo interpretar los resultados. Marco regional La tasa de incidencia anual media de la tuberculosis en Brasil es de unos 90 casos por cada 100 000 habitantes. Sin embargo, la coinfección con el virus de la inmunodeficiencia humana y la multirresistencia son relativamente poco frecuentes (10 % y < 2 %, respectivamente). Cambios importantes De las muestras de esputo sometidas a prueba, el 7,3 % fueron demasiado escasas para Xpert y tuvieron que ser examinadas con microscopio. El diez por ciento de los equipos Xpert necesitó piezas de repuesto, pero estas no estaban disponibles en el país. La ausencia de números de identificación de pacientes dio lugar a la introducción de errores en el sistema de información médica. Lecciones aprendidas La expansión nacional del sistema Xpert necesita un proveedor de servicios local que se haga cargo del mantenimiento del sistema. También es fundamental garantizar la disponibilidad de los cartuchos, y debería conservarse la capacidad de realizar microscopias de frotis. El sistema de información médica debe mantenerse actualizado para permitir un uso eficiente de Xpert.

Résumé Problème L'Organisation mondiale de la Santé a approuvé Xpert MTB/RIF (Xpert), un test automatisé basé sur l'amplification en chaîne par polymérase, pour le diagnostic rapide de la tuberculose (TB). Cependant, l'utilisation à grande échelle d'une nouvelle technologie exige une préparation et une adaptation préalables. Approche Une étude de mise en œuvre pilote a été menée dans deux villes du Brésil pour étudier le remplacement de l'examen au microscope des frottis d'expectoration par Xpert. Les laboratoires inclus couvraient 70% des cas de TB diagnostiqués, ne présentaient pas de chevauchement dans les bassins de vie des populations, traitaient différentes charges de travail et basculaient aléatoirement vers l’utilisation de Xpert. Les échantillons d'expectoration étaient recueillis avec les mêmes procédures de routine. Avant l'étude, le système d'informations médicales a été préparé pour l'enregistrement des résultats Xpert. Les techniciens de laboratoire ont été formés à l'utilisation des machines Xpert, et le personnel de santé a appris à interpréter les résultats. Environnement local Le taux moyen annuel d'incidence de la TB au Brésil est d'environ 90 cas pour 100 000 habitants. Cependant, la co-infection avec le virus de l'immunodéficience humaine et la multirésistance aux médicaments sont relativement peu fréquentes (10% et > 2%, respectivement). Changements significatifs Parmi les échantillons d'expectoration testés, 7,3% étaient insuffisants pour Xpert et ont dû être examinés par microscope. Dix pour cent de l'équipement Xpert a dû être remplacé, mais les pièces de rechange n'étaient pas facilement disponibles dans le pays. L'absence de numéros d'identification des patients a conduit à l'apparition d'erreurs dans le système d'informations médicales. Leçons tirées Pour un déploiement à l'échelle du pays, un prestataire de service local est nécessaire pour la maintenance du système Xpert. Assurer la disponibilité des cartouches est également indispensable. La capacité à effectuer les examens des frottis par microscope doit être maintenue. Le système d'informations médicales doit être mis à jour pour permettre l'utilisation efficace de Xpert.

Novas tecnologias para o diagnóstico da tuberculose foram recentemente recomendadas pela Organização Mundial da Saúde (OMS). Algumas recomendações da OMS incluem a elaboração de um plano estratégico para a adequação da rede, investimentos em supervisão e controle de qualidade, implementação de um sistema de gerenciamento de ambiente laboratorial, sem o que nenhuma nova tecnologia poderá ser eficazmente incorporada. Realizamos um levantamento da rede laboratorial de tuberculose no Brasil para identificar possíveis gargalos para a incorporação dessas tecnologias. Identificamos escassez de recursos para supervisão e controle de qualidade, baixa solicitação de culturas, ausência de sistemas eficazes de informação laboratorial e o desconhecimento da rede periférica municipal quanto às necessidades futuras na infraestrutura.

The World Health Organization (WHO) has recently recommended new technologies for the diagnosis of tuberculosis. The WHO recommendations include the development of a strategic plan for bringing the network up to grade; investment in supervision and quality control; and implementation of a system of laboratory environmental management. Without those measures having been taken, no new technology can be effectively incorporated. We surveyed the tuberculosis laboratory network in Brazil in order to identify possible bottlenecks for the incorporation of new technologies. We identified a lack of resources allocated to supervision and quality control; a low number of requests for cultures; a lack of effective laboratory information systems; and a lack of awareness regarding the future infrastructure needs of the laboratory network at the municipal level.

OBJETIVO: Este estudo visa avaliar a eficácia do tratamento cirúrgico da fibrilação atrial com ablação por ultrassom, concomitante à cirurgia valvar mitral, em pacientes do Pronto Socorro Cardiológico de Pernambuco (PROCAPE) portadores de fibrilação atrial permanente. MÉTODOS: De março 2008 até janeiro 2009, foi realizado no PROCAPE um estudo prospectivo com 44 pacientes consecutivos, portadores de fibrilação atrial permanente e indicação de cirurgia valvar mitral. Vinte e dois pacientes foram submetidos à ablação com ultrassom no epicárdio do átrio direito (AD) e no endocárdio do átrio esquerdo (AE) concomitantemente ao reparo valvar. Os outros 22 pacientes foram submetidos ao procedimento valvar sem ablação por ultrassom. Pacientes com doença coronária diagnosticada e outras enfermidades graves foram excluídos da pesquisa. RESULTADOS: Foi observada 90% de reversão da FA a ritmo sinusal no pós-operatório imediato dos pacientes que receberam ablação por ultrassom concomitante ao reparo mitral. A evolução no pós-operatório tardio mostrou queda na permanência da reversão a sinusal, porém o grupo que recebeu intervenção ainda apresentou percentual superior a 27% em relação ao grupo controle. Dos 22 pacientes submetidos à ablação com ultrassom, 86,40% apresentaram melhora da classe funcional e não foi constatado neste grupo maior ocorrência de complicações do que no grupo que foi submetido à correção valvar sem ablação. CONCLUSÃO: Os resultados apresentados pelo estudo demonstraram que os pacientes submetidos a tratamento cirúrgico da FA, com aplicação de ultrassom concomitante à correção valvar, apresentaram vantagens em relação ao grupo controle.

OBJECTIVE: This study aims to evaluate the surgical treatment of atrial fibrillation with ultrasound ablation concomitant to mitral surgery in PROCAPE's patients with permanent atrial fibrillation. METHODS: From March 2008 through January 2009 a prospective study was performed at the Pernambuco Cardiology Emergency Facility on 44 consecutive patients with a permanent atrial fibrillation and concomitant cardiac valvular surgery indication, from March 2008 through January 2009 at Pernambuco Cardiology Emergency Facility Twenty two patients underwent epicardial ultrasonic ablation on the right atrium and had ultrasonic ablation performed in the left atrium endocardial concomitant with the valve procedure. The other 22 patients, the concurrent controls were submitted to valve procedure without ultrasonic ablation. Patients with serious diseases such as coronary and others were excluded of the research. RESULTS: It was observed 90% restoration to sinus rhythm immediately after surgery in patients submitted to treatment of atrial fibrillation with ultrasound ablation simultaneous a mitral surgery. The evolution in late post operation showed that the maintenance of sinus rhythm drops although it was still 27% higher in the group which received ablation compared with the control group. 86.40% of the patients who received ablation had improved in functional class; they also have fewer complications than patients in the control group. CONCLUSION: The results showed that the patients who received treatment for atrial fibrillation simultaneously with valvar surgery had advantages related to the control group.

FUNDAMENTO: Otimização da veia safena na revascularização miocárdica. OBJETIVO: Apresentar a técnica no-touch de preparo da veia safena. Essa técnica consiste na retirada da veia safena do seu leito, com um pedículo de tecido adiposo, protegendo-a contra espasmos, sendo desnecessário distendê-la. MÉTODOS: Estudo prospectivo e randomizado, incluindo 156 pacientes submetidos a cirurgia de revascularização miocárdica. Comparação da técnica no-touch com duas outras técnicas: convencional e intermediária. Procedeu-se à avaliação da morfologia endotelial, utilizando a microscopia. A perviabilidade das pontes foi determinada com exame angiográfico num período médio de 18 meses após a operação. A enzima óxido nítrico sintetase endotelial (eNOS) foi identificada por meio do estudo imunohistoquímico. RESULTADOS: A avaliação morfológica mostrou integridade endotelial de 97% nas veias do grupo no-touch; enquanto quase metade da superfície endotelial das veias tratadas pelas outras técnicas exibiu ausência de células endoteliais. A angiografia revelou perviabilidade de 95,4% para as pontes do grupo no-touch, 88,9 e 86,2% para as pontes do grupo convencional e intermediária, respectivamente. O estudo imunohistoquímico revelou a presença da eNOS nas três camadas que compõem a parede da veia no grupo no-touch e redução dessa enzima no grupo convencional. CONCLUSÃO: A integridade endotelial e a atividade da eNOS foram melhor preservadas com o uso da técnica no-touch. A proteção mecânica fornecida pelo tecido gorduroso circundante à veia e a atividade vasodilatadora e bloqueadora da agregação plaquetária causada pelo óxido nítrico podem ser responsáveis pela proteção da veia contra o espasmo, como também por sua alta perviabilidade imediata.

BACKGROUND: Optimization of the saphenous vein for myocardial revascularization. OBJECTIVE: To present the no-touch technique of the saphenous vein preparation. This technique consists of harvesting the vein with a pedicle of surrounding tissue, which protects the vein from spasms, obviating the need for distension. METHODS: A prospective, randomized study with 156 patients who underwent artery bypass grafting was performed comparing three saphenous vein harvesting techniques: conventional, intermediate, and no-touch. A morphological study of the endothelium was carried out using scanning microscopy. An angiographic assessment of the vein graft patency was performed at a mean follow-up time of 18 months. Also, an immunohistochemical assessment was carried out to identify the endothelial enzyme nitric oxide synthase (eNOS) in the vein wall RESULTS: The preservation of the endothelial cell integrity was greater in the no-touch technique than in the other procedures. At angiographic follow-up, the patency for the no-touch group was 95.4%, 88.9% for the grafts of the conventional technique group, and 86.2% for the grafts performed in the intermediate technique group. The immunohistochemical assessment revealed eNOS in all three layers of the vein wall in the no-touch group and reduction of this enzyme in the conventional group. CONCLUSION: The endothelial integrity and eNOS activity were better preserved when using the no-touch technique for vein graft harvesting. The mechanical protection provided by the cushion of surrounding tissue in the no-touch group, the vasorelaxation and thromboresistant activities of nitric oxide may be responsible for the reduction of vasospasms and improved patency rate.

OBJETIVO: Descrever a técnica e avaliar os resultados imediatos da utilização do bisturi ultra-sônico nas esqueletizações da artéria torácica interna, na cirurgia de revascularização do miocárdio. MÉTODO: Foram operados com essa técnica 188 pacientes submetidos à cirurgia de revascularização do miocárdio, no período de janeiro de 2000 a outubro de 2006. Setenta e um (37,8%) pacientes eram do sexo feminino. A idade variou de 28 a 81 anos. A técnica utilizada na dissecação consistiu em expor toda artéria torácica interna, abrindo-se a fáscia endotorácica com tesoura o mais próximo possível da adventícia da artéria. Com o bisturi ultra-sônico é feita a secção dos ramos colaterais e sua respectiva hemostasia, dispensando-se o uso de "clips" metálicos na artéria torácica interna. RESULTADOS: As artérias torácicas internas esqueletizadas com bisturi ultra-sônico apresentaram fluxos excelentes, não sendo necessárias manipulações intraluminais para vasodilatação. No pós-operatório imediato, dois pacientes apresentaram paralisia temporária da hemicúpula diafragmática esquerda. Não houve infecção do esterno nesta série. O tempo de dissecação foi de aproximadamente 33 minutos, mas com o aumento da experiência esse tempo pôde ser reduzido. CONCLUSÃO: Essa técnica facilita e abrevia o procedimento da esqueletização da artéria torácica interna, não promove espasmos e a cauterização dos ramos colaterais com o bisturi ultra-sônico é eficiente, dispensando o uso de "clips" metálicos. É um procedimento de fácil reprodução, podendo ser recomendado para sua realização de maneira preferencial.

OBJECTIVE: To describe the technique and evaluate the immediate results of using an ultrasonic scalpel in the skeletonization of the internal thoracic artery for coronary artery bypass grafting surgery. METHODS: From January 2000 to October 2006, 188 patients were submitted to coronary artery bypass grafting with the internal thoracic artery skeletonized using an ultrasonic scalpel. Seventy-one patients (37.8%) were women. The patients' ages varied from 28 to 81 years old. The entire internal thoracic artery was exposed opening the endothoracic fascia using scissors as close as possible to the arterial adventitia. An ultrasonic scalpel was used to transect and coagulate all the intercostal branches, thereby minimizing the use of metallic clips. RESULTS: The skeletonized internal thoracic arteries presented with excellent flow, obviating the need for intraluminal manipulation for vasodilatation. In the immediate postoperative period, two patients were found to have temporary left-sided diaphragmatic paralysis. There were no sternal wound infections in this series. The dissection can be performed in approximately 33 minutes however with more experience this time may be reduced. CONCLUSION: This technique facilitates and shortens the internal thoracic artery skeletonization procedure and does not cause arterial spasms. Cauterization of the collateral branches with an ultrasonic scalpel is efficient and the use of metallic clips is almost unnecessary. It is a procedure that is easy to reproduce and may be recommended as the first-choice technique for the dissection of the internal thoracic artery.