RESUMO
The development of a ventricular assist device is depicted. The seven subprograms that make up the project are described briefly. Results obtained during the clinical assay showed that the new design of the input cannula working as a false auricle provides better efficiency, as well as a certain level of autoregulation for the device.
Assuntos
Coração Auxiliar , Idoso , Animais , Materiais Biocompatíveis , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Cateterismo/instrumentação , Fontes de Energia Elétrica , Desenho de Equipamento , Feminino , Átrios do Coração , Hemorreologia , Humanos , Masculino , Pessoa de Meia-Idade , Poliuretanos , Reprodutibilidade dos Testes , Ovinos , Propriedades de SuperfícieRESUMO
We propose a new design of the auricular cannula in ventricular assist devices (VADs), consisting of a collapsible large cannula with a capacity approximately equal to the ejection volume of the VAD. The device works as a false auricle and filters the negative pressure that occurs during diastole. We show that the use of this type of cannula improves the hydrodynamic efficiency and the stability of the working conditions. Moreover, during chronic implantation in sheep, hemolysis stays well below pathological levels. These improvements result in much better controllability of the whole VAD.
Assuntos
Coração Auxiliar , Hemodinâmica , Animais , Cateterismo Cardíaco/instrumentação , Desenho de Equipamento , Modelos Cardiovasculares , Modelos Estruturais , OvinosRESUMO
We report on the first human implantation of the BCM 3.5 ventricular assist device in a 46-year-old man suffering from terminal stage cardiomyopathy. The circulatory support was used as a bridge to heart transplantation. The patient was in cardiogenic shock and was on assisted circulation for 18 days after which he underwent cardiac transplantation. While receiving support from the ventricular assist device, the patient's condition improved remarkably and 50 days after transplantation he was discharged from hospital. We give a detailed description of the surgical technique, with special emphasis on the procedures for air extraction. We describe the evolution of the hemodynamic status before and after implantation. Final inspection of the device and cannulae after removal showed no thrombi and only small fibrin deposits in the membrane-wall junction.
Assuntos
Cardiomiopatia Dilatada/cirurgia , Eletrocardiografia/instrumentação , Insuficiência Cardíaca/cirurgia , Transplante de Coração/instrumentação , Coração Auxiliar , Desenho de Equipamento , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
1. Analysis of biochemical parameters were carried out on material pooled from 30 female sheep (Ovis aries ligeriensis). 2. The values determined were for the common metabolites and enzymes utilized for specific studies in general metabolism (urea, glucose, cholesterol, lipids, bilirubin, uric acid, creatinine, alkaline phosphatase, GOT, GPT, LDH, LAP, CGT, CK and amylase). 3. Results of these studies were compared with values from normal human adults. 4. The differences obtained in human and sheep ranges can be explained by the different physiology of the two species. 5. This study gives values for the sheep as an experimental animal in biomedical research.
