Temporary mechanical circulatory support for severe cardiac failure: experimental study.
We describe a technique for mechanical cardiac assistance in an acute model of severe cardiac failure. Cardiac dysfunction was induced by a high dose of halothane in 13 dogs. Seven served as controls. Following median sternotomy, a pneumatically driven device was implanted in the other six dogs in a para-aortic position, using a simple surgical technique without cardiopulmonary bypass. The aorta was cross-clamped during cardiac assistance. During hemodynamic studies, the seven control animals with induced cardiac failure showed high end-diastolic left ventricular and right atrial pressures with low cardiac index and systolic left ventricular and aortic pressures. All dogs in this group died within 30 minutes. Use of a monovalvular cardiac assist device in the experimental group of six dogs to pump blood from the aortic root to the descending aorta in a counterpulsation manner, confirmed good preservation of systemic hemodynamic parameters after induction of heart failure. All animals in this treated group survived more than 45 minutes. Hemodynamically, the device acts as a new ventricle and the impaired left ventricle functionally becomes a left atrium. This condition is clinically appropriate for recovery of left ventricular function in severe acute myocardial failure.
Department of Cardiac Research, Favaloro Foundation, Buenos Aires, Argentina.
E I
EI
Cabrera Fischer
J C
JC
Chachques
A
A
Garcia
R H
RH
Pichel
M C
MC
Morales
A
A
Carpentier
D000818:Animals; D015908:Counterpulsation / Q000295:instrumentation*; D004285:Dogs; D004867:Equipment Design; D006221:Halothane; D006333:Heart Failure / Q000139:chemically induced / Q000628:therapy*; D006353:Heart-Assist Devices; D006439:Hemodynamics / Q000502:physiology*
D006221:Halothane