Impella: a miniaturized cardiac support system in an era of minimal invasive cardiac surgery.

In modern coronary bypass surgery, new objectives have been set based upon a minimal invasive approach: beating heart surgery is the new trend to follow, although this might not be feasible in more complex cases. In these cases, the beating heart could be supported by a mechanical device, preferably a device with minimal invasive features to fit in this new approach. For this purpose, two intravascular blood pumps were developed: the Intracardiac Pump LV for left ventricular support and the Intracardiac pump RV for right ventricular support. (Impella Cardiotechnik, Aachen, Germany) The Impella pumps are rotary blood pumps of the axial flow type and produce 4.2 L/min at physiological pressure differences and a rotational speed of 32,500 rotations/min. These micropumps can widen the indications of beating heart surgery by sustaining hemodynamic stability and protecting the heart from warm ischemia. The current concept is aimed at bridging a procedure. Therefore, the proof of safe duration of usage has not been extended beyond 6 hours. As the pump-flow is based on standard pressure-flow curves for each so-called "performance level" (resulting from in-vitro experiments), an investigation was conducted to compare this relationship in the in-vitro trials with the findings in pump-supported patients undergoing coronary bypass surgery. It could be concluded that the intracardiac pump is efficacious in assisting coronary bypass surgery.