ABSTRACT

From May/1990 to March/1992, 81 "Stentless" porcine bioprosthesis were implanted in the aortic position in three Centers: Biocor Institute (34 patients), University of Torino (31 patients) and Karolinska Hospital (16 patients). The age ranged from 14 to 85 years, with a mean age of 51. There were 48 male patients and 33 femele; the post operative follow-up ranged from 1 to 22 months (mean = 7 months). The main indication was aortic stenosis. There were 5 patients with acute endocarditis of the native aortic valve, with significant hemodynamic impairment, and presence of annular abscesses in 3 of them. All patients were operated on under moderate hypothermia and myocardial protection, with cristalloid cardioplegia. The "Stentless" bioprosthesis was inserted using two layers of a 4-0 Prolene running suture. All patients survived the operation; there were 4 early deaths (4.93%) and one late death secundary to pulmonary embolism (16 th months post. op.). The major hospital complication was complete AV block in 7 patients. All patients are in regular clinical follow-up, including hemodynamic assessment by echodopplercardiography. The preliminary data show an excellent hemodynamic performance of the "Stentless" bioprosthesis.

RESUMO

No período de maio de 1990 a março de 1992, 81 pacientes foram submetidos a implante de urna bioprótese aórtica sem suporte Stentlessem três centros: Biocór Hospital (34 pacientes), Universidade de Turim (31 pacientes) e Hospital Karolinska (16 pacientes). A idade variou de 14 a 85 anos, com média de 51 anos. Quarenta e oito pacientes eram do sexo masculino e 33 do sexo feminino. O período de acompanhamento pré-operatório variou de 1 a 22 meses. A principal indicação para a cirurgia foi a estenose aórtica, destacando-se 5 pacientes que apresentavam endocardíte aguda da valva aórtica com presença de severo comprometimento do anel em 3 deles. Todos os pacientes foram operados sob hipotermia moderada e proteção miocárdica com cardioplegia cristalóide. A técnica básica do implante da bioprótese foi com duas camadas de chuleio contínuo de Prolene 4 zeros. Todos os pacientes sobreviveram à cirurgia. Houve 4 (4,93%) óbitos no pós-operatório imediato e 1 (1,23%) óbito tardio no 16º mês de pós-operatório secundário a trombo-embolismo pulmonar. A principal complicação pós-operatória foi o bloqueio AV total, em 7 pacientes. O estudo ecocardiográfico realizado em todos os pacientes mostrou gradientes que variaram de 6 a 12 mmHg. Todos os pacientes encontra-se em controle clínico, incluindo avaliação hemodinâmica pela ecodopplercardiografia. Os resultados preliminares desta nova bioprótese são promissores com relação à sua performance a longo prazo, sendo a observação tardia fundamental na confirmação dos excelentes resultados iniciais.

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