Abstract
The optimal balloon timing, when VA-bypass and IABP are applied simultaneously, has not been well known. Using Mock circulation model, we evaluated which deflation timing of IABP balloon is optimal for left ventricular (LV) afterload reduction during VA-bypass. LV afterload due to VA-bypass was not unloaded when balloon was deflated in early presystole (160-120msec prior to R wave of ECG). However, afterload was linealy reduced along with the delayed deflation of balloon until 40 msec after R wave. During VA-bypass, the afterload reduction effect of IABP would be optimal, when balloon is deflated as late presystole as possible.
