José Luiz Verde dos Santos

Dynamic cardiomyoplasty in chronic chagas' heart disease: Clinicopathological data

We report a 44-year-old man with chronic chagasic cardiomyopathy who underwent latissimus dorsi dynamic cardiomyoplasty and died 4 months later. The clinicopathological findings are discussed, and the literature is reviewed.

Cardioplegia sangüínea contínua normotérmica

Os autores discutem o emprego da cardioplegia, bem como sua composicao. A parada imediata dos batimentos pode ser conseguida com solucoes cardioplegicas cristaloides ou sanguineas, oxigenadas ou nao. O agente que leva o coracao a parada pode ser potassio, magnesio, procaina ou, mesmo, quelantes e bloqueadores de calcio associados entre si ou nao, contando com a edicao da hipotermia ou nao. Deve-se ficar atento para a falsa sensacao de protecao a que a baixa temperatura possa nos induzir, uma vez que o frio, por si so, nao e suficiente para manter o miocardio viavel por longos periodos. Substratos, como glicose e oxigenio, devem ser fornecidos durante o periodo de clampeamento aortico, para garantir algum metabolismo aerobio, nesse periodo. A adicao de outros substratos, como glutamato, aspartato e lactato, assim como ATP ou creatina fosfato, precursores de intermediarios do ciclo de Krebs, podem melhorar muito a protecao miocardica. A infusao de cardioplegia sanguinea normotermica de forma continua mantem as necessidades metabolicas basicas para a sobrevivencia das celulas. A membrana celular, com todas as suas funcoes estruturais e secretoras, e o ponto mais sensivel a injuria isquemica. Os removedores de radicais livres (scavengers) sao protetores indiretos da membrana celular. A cardioplegia retrograda permite melhorar a distribuicao das solucoes na arvore coronariana, sendo muito util nas reoperacoes. Ela deve fazer parte da tatica cirurgica, sem esquecermos suas limitacoes. O momento da reperfusao e o mais importante da protecao miocardica; e nesse periodo que ocorre a liberacao de radicais livres. O uso de removedores (scavengers) pode melhorar as condicoes e o resultado da reperfusao. A cardioplegia sanguinea oxigenada e normotermica enriquecida com substratos, antes usada em casos extremamente graves, por disfuncao muscular em isquemia miocardica severa, ou por ausencia de protecao adequada, durante a fase de isquemia e/ou reperfusao, foi expandida para todos os casos. E recomendado que o coracao tenha, sempre, suas câmaras drenadas, evitando-se qualquer aumento na tensao da parede, o que levaria a maior consumo de oxigenio. Os autores descrevem a tecnica e as solucoes cardioplegicas aplicadas no Servico de Cirurgia Cardiaca do IMC e os resultados obtidos com o uso das mesmas. Concluem ser satisfatorio o uso de cardioplegia normotermica modificada e reperfusao assistolica, enriquecidas por aminoacidos, na preservacao da funcao miocardica e na reversao dos danos isquemicos.

Autotransplante cardíaco: um novo método no tratamento de problemas cardíacos complexos

No periodo de janeiro de 1990 a maio de 1995 foram operados com a tecnica do autotransplante cardiaco 92 pacientes com cardiopatias complexas e arritmias supraventriculares, principalmente fibrilacao atrial (n=89), reentrada (n=2), QT longo (n=1). O sexo feminino predominou (n=63). A idade variou de 18 a 76 anos (m=43). Os defeitos concomitantes foram: atrio esquerdo gigante (medido pelo ecocardiograma > 6 cm) (n=65); atrio direito gigante (n=9); atrio esquerdo aumentado ( 4 cm) (n=23); estenose mitral (n=46); insuficiencia mitral (n=28); dupla lesao mitral (n=16); estenose aortica (n=12); insuficiencia aortica (n=5); insuficiencia tricuspide (n=78); trombose atrial (n=23); calcificacao atrial (n=12); hipertensao pulmonar (n=86); fibroelastose biventricular (n=3); rotura atrioventricular (pos-troca de valva mitral) (n=1); aneurisma da raiz aortica (n=1); ventriculectomia parcial (n=8); 88 pacientes sairam do centro cirurgico em ritmo sinusal e assim permaneceram; 6 precisaram de drogas inotropicas e 3 de drogas antiarritmicas. Todos os pacientes que apresentavam atrio esquerdo ou direito gigante com fibrilacao atrial tiveram seus atrios reduzidos ao tamanho normal. Nao houve mortalidade operatoria e 6 evoluiram a obito hospitalar. Na reavaliacao aos seis meses de pos-operatorio, os sobreviventes estavam bem, em ritmo sinusal. A tecnica do autotransplante cardiaco facilita o reparo intracardiaco, proporciona a reducao atrial e consequente retorno do paciente ao ritmo sinusal e abre novas perspectivas.

Substituição completa da aorta ascendente e da valva aórtica com tubo valvulado de pericárdio bovino

Os autores fazem uma revisao da tecnica cirurgica empregada para o tratamento de aneurismas da aorta ascendente associados a lesoes da valva aortica. Apresentam resultados obtidos com 11 (onze) paciente operados pela tecnica de BENTALL e DE BONO, com enxerto tubular valvulado aberto de pericardio bovino IMC, sem mortalidade devida a tecnica ou ao enxerto utilizado. Desses pacientes, 8 eram do sexo masculino, com idade variando entre 31 e 65 anos, media de 50 anos; 3 eram do sexo feminino, com idade entre 20 e 53 anos, media de 38 anos. Duas cirurgias foram realizadas, em regime de urgencia, e 9 de emergencia. O tubo de pericardio bovino utilizado foi de no 23 em 1 caso, no 25 em 2, no 29 em 6 e no 31 em 2 casos. Dois pacientes tiveram lesao mitral associada com troca valvar (protese biologica IMC). Um paciente necessitou de ponte de veia safena para coronaria direita, por disseccao do ostio coronario. O diagnostico histopatologico mostrou: degeneracao mixomatosa em 4 casos, fibrose em 4 casos, doenca reumatica cicatrizada em 2 casos e pancardite em apenas 1 caso. Apos discorrerem sobre dificuldades e complicacoes do metodo, concluem que a tecnica utilizada e a de escolha no tratamento da referida patologia e que o tubo valvulado de pericardio bovino facilita o ato cirurgico, por sua alta flexibilidade e por ser altamente hemostatico, nao necessitando de medidas pre-coagulativas.

Seguimento de 9 anos da bioprótese valvular cardíaca de pericárdio bovino IMC-Biomédica: estudo multicêntrico

A mitral pericardial bioprosthetic valve IMC-Biomedica was implanted in a consecutive series of 798 patients with mean age of 52 years, from December 1977 to November 1978. The 722 patients who survived operation were observed during a period of 9 years (mean 27036 months or 2253 years). Actuarial studies indicated an expected survived rate at 9 years of 66% for adult patients and 68% for younger patients. The probability of complications were the following: rupture 0.4; perivalvar leak 0.4%; thromboembolysm 2.7%; endocarditis 3.2%; calcification 4.4%. The actuarial freedom from calcification between 1977 to 1982 (Group I) was 94.0% to adults and 12.0% to younger patients. On the other hand, between 1982 to 1986 (Group II) the actuarial analysis of calcification showed that 99.0% adults and 92.0% younger patients were free from this complication. Hence we believe that our option for the pericardial bioprosthetic valve was appropriate because 96.0% patients were free of complications deaths with the valve; this means that in 9 years the bioprosthetic lethal potential was only 4.0%.

Ligadura do canal arterial: técnica extrapleural

The authors describe the surgery for patent ductus arteriosus (PDA) with triple ligature through the extrapleural path. After general anesthesia, the child has his position in the right lateral and a little ventral decubitus. A small incision is made in the inferior limit of the scapula. The pleura is dissected and the PDA exposed, double ligated with Polyester 2/0 and transfixed and tightened with Polypropilene 4/0. With this technique it is not necessary to have a chest tube. Fourty seven patients with PDA were submitted to surgery between September 1988 and August 1990; in 40 patients it was possible to do this type of surgery. Ages ranged from 4 months to 11 years, with mean age of 3.1 ± 3.0 years. Twenty children were less than one year old. There were 24 females and 16 males. No cases of intra or post-operative complications were registered. The follow-up ranged from 7 to 30 months (mean 15.3 months). Ali children were submitted to clinical evaluation, thoracic Rx and ecocopplercardiography. No patients presented recanalization or other complications. This experience showed that this tecnique is reliable, efective and it does not present immediate and late morbility or mortality. This technique can be safely used in younger as well as older children.

Avaliação de tubo valvulado de pericárdio bovino em um modelo experimental animal

Congenital diseases as pulmonary atresia, tetralogy of Fallot, among others, have been corrected using the extracardiac conduits. There is a variety of conduits valved or not that make possible the access of sanguineous flux from right ventricle to pulmonary circulation. However, the synthetic conduits with biologic or metalic valves shows prosthesis degeneration and obstruction problems and peeling of the conduit, moreover, they are very expensive. The experience with treated bovine pericardium showing it is impermeable and easy to suture, led to the production of valved conduits that in this study were evaluated for obstruction, calcification and stretching. The utilization of an animal experimental model allowed the detailed periodic evaluation by echodopplercardiography and cateterism during one, three and six months. The recuperated conduits were studied by optical microscopy and X ray, with several parts of the bioprosthesis analysed. The microscopic examination showed the conduits pericardium preserved with signs of pseudo-endotelization, and the majority of valves with moderate calcification, but with good function yet. The surgery technique without extracorporeal circulation and the results with the follow-up of five animals during six months are presented and discussed. The authors conclude that the bovine pericardium valved conduit showed good results in the right ventricule outlet, allowing to expect a satisfatory result when applied in human beings by the known relation of acelerated degeneration of the biological prostheses on the studied experimental model, several times greater than in man.

Aneurisma do seio de Valsalva: análise de sete casos

The authors present their experience on seven cases of Valsalva-sinus aneurysm (VSA) at the Instituto de Molestias Cardiovasculares (IMC), from January 1984 to July 1990, treated surgically using bovine pericardium patch (PB-IMC) or valve replacement when indicated. Five cases were congenital and two were related to rheumatic disease. In two of the congenital cases the aneurysms were leaking into the right atrium, two were leaking into the right ventricle. And the remaining one was not leaking but was projected into the left ventricle. One of the congenital cases was leaking into the right ventricle and the other presented protrusion of the aneurysmatic sac into the left ventricle and eversion of the corresponding aortic leaflets. A bovine pericardium patch was used to give support for he sutures inxthe congenital ASV cases; for the cases related to rheumatic disease a valve replacement was performed using an IMC-PB biologic valve. From the congenital VSA patients, one had deiscence of suture at seven months and at six years, and was submitted to reoperation in both occasions. In the related to rheumatic disease group one died due to stroke on the 15 th postoperative day. The use of PB patch proved satisfactory in this treatment, providing good support for the suture.