EXPERIMENTAL-STUDY OF EXTRAAORTIC BALLOON COUNTERPULSATION AS A BRIDGE TO OTHER MECHANICAL ASSISTS

A special extraaortic balloon was developed that can be placed around the ascending aorta. This balloon can easily support the heart tempora rily in a median sternotomy field, especially in cases in which it is difficult to use intraaortic balloon pumping because of peripheral art erial disease. The goal of this study was to judge the applicability o f this extraaortic balloon counterpulsation. An extraaortic balloon wa s placed around the ascending aorta of eight adult canines. Two heart failure models were used in this study: group A - moderate heart failu re; group B - severe heart failure. In group A, the aortic systolic pr essure was significantly reduced (9.3%, p < 0.01), but in group B, the re was no significant change. In group A, there was a significant incr ease in cardiac output (12.0%, p < 0.01), but in group B, there was no significant change. The endocardial viability ratio in both groups si gnificantly increased (group A: 11.3%, p < 0.01; group B: 11.9%, p < 0 .05). An extraaortic balloon around the ascending aorta is easily appl icable through a median sternotomy, and can be used as a bridge to mor e powerful mechanical assists when intraaortic balloon pumping cannot be used.