The purpose of this study was to compare the hemodynamic effectiveness
of a 30-ml stroke volume paraaortic counterpulsation device (PACD),
presenting the advantages of ease of implantation and driving by a
standard intraaortic balloon pump (IABP) console (Datascope 96,
Datascope Corp., Montvale, NJ, USA) to that of a 40-ml IABP, in the
setting of experimental heart failure. In an acute heart failure model,
the IABP was placed in the descending aorta and the PACD in the
ascending aorta of eight pigs. Both devices were driven by the same
system, and hemodynamic measurements were obtained with and without
mechanical assistance. The two pumps significantly reduced the systolic
and end-diastolic aortic pressures, but the PACD reduced the latter more
effectively (42.6 +/- 18.1% vs 11.0 +/- 9.9%,p = 0.0001). Both pumps
provided significant aortic diastolic augmentation, but the
counterpulsation wave of the PACD was significantly greater
(augmentation of 44.8 +/- 22.2% vs 37.6 +/- 15.6%, p = 0.031). Both
lowered the end-diastolic left ventricular pressure with a trend toward
PACD superiority (24.2 +/- 13.7% vs 19.7 +/- 13.5%,p = 0.064). It is
concluded that the PACD, even with smaller stroke volume, is more
effective than the IABP. The simplicity of its implantation, together
with the ability of the standard IABP consoles to control its function,
make it a promising device for mechanical assistance of the failing
heart
