José Carlos Silva de Andrade

Coronary artery bypass grafting without cardiopulmonary bypass

BACKGROUND Coronary artery bypass grafting without cardiopulmonary bypass is now an accepted technique of myocardial revascularization. We herein report our total experience with this procedure. METHODS In a consecutive series of 8,751 patients operated on in our institution for coronary artery disease from 1981 to 1994, 1,274 patients received coronary artery bypass grafting without cardiopulmonary bypass. RESULTS Results indicate that the operation can be performed with an acceptable mortality (2.5%), and that all types of arterial conduits can be used. Most commonly the left anterior descending and right coronary arteries were bypassed. The incidence of arrhythmias and of pulmonary and neurologic complications were significantly lower in this group of patients compared with patients receiving coronary artery bypass grafting with cardiopulmonary bypass. Most importantly, there was decreased cost when the procedure was used because no extracorporeal circulation, cardioplegia sets, or other cannulas were used. CONCLUSIONS We conclude that the continuing use of coronary artery bypass grafting without cardiopulmonary bypass is justified and that, with proper selection of patients, the procedure is safe and cost-effective.

Surgical Treatment of Acute Type B Aortic Dissection Using an Endoprosthesis (Elephant Trunk)

BACKGROUND The surgical treatment of acute complicated type B aortic dissection continues to be a challenge and is still associated with high morbidity and mortality rates. METHODS Seventy consecutive patients with an acute type B aortic dissection underwent an elephant trunk procedure through a median sternotomy during deep hypothermic circulatory arrest. An endoprosthesis that was 22 to 24 mm in diameter was inserted through an incision in the arch and held in place with only proximal sutures. RESULTS The mean arrest time was 31.4 +/- 8.7 minutes, and it was possible to adequately position the endoluminal graft in every patient. The procedure was done in association with other procedures in 13 patients. There were six in-hospital deaths not related to the endoprosthesis, and four late deaths. Late reoperation was necessary in 6 patients to manage leakage at the proximal suture line. CONCLUSIONS The insertion of an endoprosthesis through the arch for the management of a complicated acute type B dissection has several advantages over the conventional thoracotomy approach. The hospital mortality rate in this series of 70 patients was 20%, and the actuarial 5-year survival rate was 62.5%. We consider the elephant trunk procedure the treatment of choice in patients with type B acute dissections, regardless of whether the dissection is complicated or not.

Transplante cardíaco ortotópico: experiência na Universidade Federal de São Paulo

Foram realizados no periodo de novembro de 1986 a abril de 1997, 92 transplantes ortotopicos, com receptores na faixa etaria de 3 a 63 anos (media de 44,9 anos). Os diagnosticos pre-operatorios foram de miocardiopatia dilatada em 42 (44,6%) pacientes, isquemica em 23 (25,0%), chagasica em 21 (22,8%), valvar em 3 (3,2%) e outras miocardiopatias em 3 (3,2%) pacientes. A tecnica operatoria empregada (Lower e Shumway, em 1960) foi satisfatoria e sem complicacoes. O tempo de isquemia - mais longo nos transplantes com captacao a distância - foi sempre inferior a quatro horas. As complicacoes relacionadas ao uso cronico de imunossupressores foram, principalmente, hipertensao arterial (84,6%), hiperuricemia (75,4%) e dislipidemia (63,0%). Quanto as infeccoes, houve predominio das virais, com 42 (45,6%) casos, seguidas das bacterianas, com 35 (38,0%) casos, e das por protozoarios, com 15 (16,3%) casos. Dentre as infeccoes bacterianas, sete foram do sitio cirurgico, com boa evolucao. Das infeccoes por protozoarios, sete (46,6%) forma por reativacao do Trypanosoma cruzi. A mortalidade geral nos primeiros 30 dias do pos-operatorio foi de 17,3% e teve, como principais causas: infeccao, complicacoes neurologicas e rejeicao. Apos esses 30 dias e ate o primeiro ano, houve 10 (10,3%) obitos, com predominio de rejeicao e infeccao como causas. Apos o primeiro ano de pos-operatorio, houve 13 (14,0%) falecimentos, por causas diversas, como: morte subita, infeccao, rejeicao, alem de outras. A curva actuarial mostrou no 1o, 2o, 3o, 4o, 5o e 6o anos uma sobrevivencia de receptores de 71,6%, 66,6%, 60,5%, 54,4%, 54,4%, 54,4%, respectivamente. Nao houve perda de seguimento de paciente, e os sobreviventes ate a conclusao do trabalho encontravam-se bem, todos em classe funcional I da NYHA. Os autores concluem que e possivel a realizacao de transplante cardiaco em nossa comunidade com sobrevivencia e taxa de complicacoes pos-operatorias aceitaveis, porem diferentes das estatisticas internacionais.

Tratamento dos aneurismas da aorta descendente por endoprótese (tromba de elefante)

Os aneurismas da aorta descendente ainda causam grande mortalidade e morbidade, apesar dos avancos da cirurgia cardiovascular moderna. Neste trabalho utilizamos, originalmente em nosso meio, uma tecnica recente que consiste na insercao de uma protese de Dacron intraluminar, suturada apenas em sua porcao proximal, logo apos a subclavia esquerda e que transpoe a zona do aneurisma, ficando solta no interior da aorta em sua porcao distai (tromba de elefante). A operacao e realizada com circulacao extracorporea, hipotermia profunda de 19oC, com parada circulatoria no tempo suficiente para a insercao da protese e sutura da sua borda proximal. Desde maio de 1988, oito pacientes fizeram parte deste estudo, sendo que seis eram disseccoes da aorta tipo B e dois casos, aneurismas verdadeiros. A simplicidade e rapidez do procedimento, assim como os resultados pos-operatorios obtidos nos animam a prosseguir e recomendar este tipo de alternativa tatica, especialmente nas disseccoes de aorta tipo B.

Revascularização do miocárdio sem circulação extracorpória: análise dos resultados em 15 anos de experiência

Myocardial revascularization without cardiopulmonary bypass is now a subject of increasing interest. The purpose of this paper is to present the results obtained during 15 years of experience. From September 1981 till March 1996,1549 patients we operated on without the use of cardiopulmonary bypass with an applicability of this alternative around 18% of the total revascularized patients in this period. The ages varied from 28 to 86 years (medium 57) with 1126 males and 423 females. The number of grafts varied from 1 to 5 (medium 1.7 grafts/patient). The technique did not constitute special limitation to use arterial grafts. The thoracic internal arteries were used 1140 times. In 1515 patients the revascularization was achieved through medsternotomy and in 34 through a minor left anterior thoracotomy. The mortality rate was 2.4% (38/1549) the main primary cause of death, low cardiac output in patients operated under acute ischemia after failed angioplasty or evolving mycardial infarction. In 8 patients the revascularization was performed under intraaortic balloon pump. The results of this 15 years experience permit the conclusion that myocardial revascularization without extracorporeal circulation is an excelent alternative of surgical treatment of coronary artery disease for a subset of patients with lower mortality and morbidity being specially indicated in high risk patients.

Avaliação dos resultados tardios da operação de derivação cavo-pulmonar bidirecional, no tratamento paliativo de cardiopatias congênitas com câmara ventricular única

From March 1990 to January 1994, 17 patients 1 to 13 years old (mean 7 years), who had congenital heart disease with functional isolated ventricular chamber, were submitted to bidirectional cavopulmonary shunts. Nine cases had Tricuspid Atresia (TA) (7 type Ib, 1 type Ic and 1 type IIb). Five cases had Double Inlet Right ventricle (Dl RV); two cases had multiple Ventricular Septal Defects (VSD) plus RV hypoplasia. One case had pulmonary atresia with Intact Ventricular septum (PA/IVS). Nine (52,9%) patients had been submitted, to previous paliative operations. The operations in 12 (70,5%) cases were with extracorporeal circulation (ECC) and in 5 (29,4%) cases with superior vena cava (SVC) to right atrio (RA) temporary shunt. In all cases the SVC was anastomosed to right pulmonary artery (RPA) closing the pulmonary valve (PV) or linking the Blalock-Taussig shunt to interrupt the pulmonary flow. There are three (17,6%) deaths in the immediate postoperative period and 2 (14,2%) late deaths. Twelve (70,5%) patients were followed-up for 2 to 46 months. One patient was submitted to the 2 nd operation, tunnelating the inferior vena cava (IVC) to RPA, with success. The assessment of bidirectional cavopulmonary flow was made with Doppler echocardiography and magnetic resonance and the pulmonary perfusion was made with radioisotopic cintilography. The indication tor the 2 nd, operation depended on the clinical evolution and assessment of arterial saturation during the cicloergometric test. The bidirectional cavo pulmonary shunt allows the progressive adaptation of the venous flow to lung and reduced ventricular volume load, preparing the patient to total venous shunt.

Reconstituição da valva pulmonar e via de saída do ventrículo direito, com prótese bivalvular e prótese tubular valvada de tronco pulmonar de porco: estudo experimental e aplicação clínica

Obstruction of the right ventricle outlet tract (RVOT) has been the object of arguments regarding its surgical correction, while there are different criteria for reconstruction. Thus two kinds of prostheses were developed from the pig pulmonary trunk (PT). 1) One with two valves of the pulmonary valve (PV), named bivalvular graft, and could be used for correction of Fallot with pulmonary ring hypoplasia. 2) The other, with a tubular form, containing the pig PV itself and named valved conduit, could be used in RVOT reconstruction for patients with pulmonary atresia (PA). These prostheses were tested in an experimental model: implant of the bivalvular graft was performed in 16 sheep with the aid of extracorporeal circulation (ECC). The surgical technique consisted of resection of the two valves of the PV and of the anterior wall of the infundibulum; this condition was similar to Fallot correction. Implant of the valvular conduit was carried out in 12 sheep, without ECC, by direct clamping of the RV infundibulum. The PT was then ligated, deviating blood flow through the conduit. Intraoperative hemodynamics and echodoppler evaluation of the bivalvular graft showed good PV competence and only 1 case of gradient higher than 10 mmHg. Because of frequent pulmonary hemorrhage followed by death due to ECC, this group was not evaluated in the postoperative period. Intraoperative hemodynamic measurements of the valvular conduit were carried out showing good valvular competence and gradient higher than 10 mmHg in 3 cases. There was no operative mortality. Seven sheeps were followed-up during the late postoperative period with a control echodoppler on days 99 and 135 of follow-up. Gradients ranged from 9.85 to 49 mmHg (mean = 19.7). Four sheep underwent hemodynamic studies at six months of follow-up. There was a slight increase in the gradient between RV and PT (mean = 22.3 mmHg), no gradient being observed inside the conduit. Anatomopathological evaluation was performed. Clinical applications of the bivalvular prostheses was performed in 3 patients with tetralogy of Fallot and hypoplasia of the pulmonary ring (2 cases) and PV absent (1 case); they were 16,2 and 7 years old. The postoperative echodopplercardiogram showed gradients between 10 to 20 mmHg and mild pulmonary valve insufficiency. Clinical application of the valvular conduit was performed in 2 patients: 1 with pulmonary atresia and ventricular septal defect (VSD), the other with corrected transposition of the great arteries, VSD and subpulmonary stenosis (10 and 6 years old, respectively). The postoperative echodopplercardiogram showed gradients between 15 to 18 mmHg. Although the results of the experiment may be considered acceptable, reconstruction of the RVOT with the newly developed prostheses, obviously requires to be tested over time to better evaluate their resistance to calcification, infection, obstruction and rupture.

Revascularização direta do miocárdio sem circulação extracorpórea: estudo crítico dos resultados em 391 pacientes

Os autores analisam os resultados obtidos em 391 pacientes consecutivos e nao selecionados e submetidos a revascularizacao direta do miocardio sem o circuito cardiopulmonar, operados de setembro de 1981 a fevereiro de 1985. Neste mesmo periodo, foram realizadas um total de 1568 cirurgias de revascularizacao, sendo esta alternativa tatica aplicavel em 24,9% dos casos. Da casuistica apresentada, 318 (81,3%) eram do sexo masculino e 73 (18,7%), do feminino e as idades de 35 a 76 anos, oscilando em torno da mediana 56. As condicoes pre-operatorias indicativas da cirurgia foram as seguintes: insuficiencia coronaria cronica 286 (73,1%) casos; pos trombolise coronaria 42 (10,7%); infarto agudo em evolucao 18 (4,6%); pos angioplastia mal sucedida 18 (4,6%); reoperacoes 14 (3,6%); sindrome intermediaria 12 (3,1%) e revascularizacao em disseccao aortica cronica 1 caso. Pontes unicas foram realizadas em 175 (44,7%) pacientes, duplas em 192 (49,1%) e triplas em 24 (6,1%), com a media de 1,6 pontes/paciente. A arteria mamaria foi usada para 109 casos, arteria mamaria heterologa bovina em 2, sendo, nos demais, utilizada a veia safena. A mortalidade hospitalar foi de 2,5% (10/391), o que difere, significativamente, da mortalidade de 5% verificada para um grupo de 1177 pacientes operados no mesmo periodo, com a circulacao extracorporea. Comparamos, prospectivamente, as complicacoes pos-operatorias observadas em um grupo de 378 pacientes operados sem a circulacao extracorporea, contra um grupo controle de 689 pacientes tratados da maneira convencional, no que diz respeito a incidencia de arritmias, infarto per-operatorio, complicacoes pulmonares, neurologicas, infecciosas e hemorragicas. Verificamos uma incidencia menor, estatisticamente significante, para as complicacoes pulmonares, neurologicas e de arritmias no grupo operado sem a circulacao extracorporea, nao diferindo das demais complicacoes entre os dois grupos. Concluem os autores que a revascularizacao do miocardio sem utilizacao da extracorporea se consolidou, ao longo destes 4 anos de experiencia, como tatica de eleicao em lesoes da coronaria direita, descendente anterior, ou ambas, face as vantagens que apresenta.

Clinical and Histomorphometric Evaluation of Fresh Frozen Bone Allograft in Sinus Lift Surgery

PURPOSE The aim of this prospective clinical study was to evaluate the clinical and histomorphometric data of newly formed bone tissue from fresh frozen human allograft in sinus lift surgery. PATIENTS AND METHODS Thirty-three sinus lift procedures were performed in 20 patients, divided into two groups. The control group (n = 8) received autogenous bone from the mandibular ramus, and the experimental group (n = 12) received fresh frozen bone (FFB) allograft in chips. After 6 months, 52 implants were placed and 50 biopsies were collected for histomorphometric analysis. Cone beam computed tomography scans were performed at preoperative, immediate postoperative, and delayed postoperative time intervals to assess the degree of graft volume loss. RESULTS There was no statistically significant difference between groups as regards degree of graft volume loss (p = .983), total bone area (p = .191), remaining particles (p = .348), and proportion of active osteoblasts (p = .867). There was a statistically significant difference in the vitality rate between the groups (p = .043). In both groups, all implants were clinically osseointegrated after 4 months. CONCLUSION FFB allograft was shown to be a feasible substitute for autogenous bone graft in sinus lift surgery.

Revascularização direta do miocárdio com artéria gastro-omental esquerda: estudo anatômico e histológico e relato de caso.

The most used grafts for myocardial revascularization are saphenous vein and the internal mammary artery (IMA); long term patency studies have shown good results with IMA. The use of the gastroepiploic artery (GEA) as a graft for direct myocardial revascularization was tested in 25 cadavers, with ages varying from 23 to 84 years obtained from the Anatomy Department at the Escola Paulista de Medicina. The surgical technique consisted in cutting down the left GEA, sectioning its collaterals and cutting it off from the right GEA at the piloric zone. The diameter and length of the artery were studied. The placement of the artery in the pericardial sac was done through rotation of the pedicle in front of the diaphragm. It was possible to anastomose it to the right coronary artery or circunflex marginal. Histological studies performed on the GEA demonstrated a medial layer of the type elastic-muscular with low incidence of atherosclerosis. The clinical application of this technique was performed in a 58 years old female who had both saphenous veins completely fibrosed. The patient received three grafts: left IMA, right IMA and GEA for the left anterior descending, right coronary artery and circunflex artery, respectively. The immediate postoperative period was uneventful and she was discharged 12 days after surgery. Digital angiography was selectively performed in each of the three grafts demonstrating good patency in all of them. This is a new possibility of direct myocardial revascularization to be utilized when the usual venous grafts cannot bem employed.