[Circulatory assist device in counterpulsation]. / Dispositivo de assistencia circulatoria em contrapulsacao.
Arq Bras Cardiol
; 55(2): 99-103, 1990 Aug.
Article
em Pt
| MEDLINE
| ID: mdl-2073183
PURPOSE: To test a circulatory assist device (CAD) developed in the University of São Paulo. Heart Institute, Bioengineering Division. It is a valveless chamber working through the counterpulsation principle, aiming at assistance to temporary the left ventricle. PATIENTS AND METHODS: The CAD consists of a rigid polycarbonate shell, which houses in its interior a polyurethane bag with a maximum volume of 110 cm3, driven alternately by pressure and vacuum from an external electropneumatic device synchronized with the ECG. The device worked for 300 hours in a test bench simulating the cardiovascular system in order to verify its resistance to wear and fatigue. The CAD was implanted near the aortic root of five dogs, in whom cardiac failure was induced through the use of propranolol and plasma expanders. The CAD was driven for five periods of 2 minutes separated by pauses of equal duration. The hemodynamic parameters were measured during the mentioned periods. RESULTS: "In vitro" testing resulted in no wear or fatigue. No leakage was observed. In the "in vivo" testing the averages obtained during the on and off periods of the device showed for the on periods; a) lowering of the systolic pressures of both the aorta (17.5%) and the left ventricle (LV) 15.1%), lowering of the final diastolic pressure of the LV (15.4%) and lowering of the diastolic pressure of the aorta (27.4%); b) increase in cardiac output (45.5%); c) increase of the endocardial viability ratio by 37.5%. CONCLUSION: The tested device represents a therapeutic option in cases of acute left ventricle failure, since with it an improved cardiac performance was measured and an increased coronary perfusion can be presumed.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Contrapulsação
/
Coração Auxiliar
Limite:
Animals
Idioma:
Pt
Revista:
Arq Bras Cardiol
Ano de publicação:
1990
Tipo de documento:
Article
País de publicação:
Brasil