The MiniACcor: Constructive Redesign of an Implantable Total Artificial Heart, Initial Laboratory Testing and Further Steps

Abstract

The Aachen Total Artificial Heart (ACcor) has been under development at the Helmholtz Institute in Aachen over the last decade. It may serve as a bridge to transplant or as a long-term replacement of the natural heart. Based upon previous in vivo experiments with the ACcor total artificial heart, it was decided to optimize and redesign the pump unit. Smaller dimensions, passive filling and separability into three components were the three main design goals. The new design is called the MiniACcor, which is about 20% smaller than its predecessor, and weighs only 470 grams. Also its external driver/control unit was miniaturized and a new microcontroller was selected. To validate the design, it was extensively tested in laboratory mock loops. The MiniACcor was able to pump between 4.5 and 7 l/min at different pump rates against normal physiological pressures. Several requirements for the future compliance chamber and transcutaneous energy transmission (TET) system were also measured in the same mock loop. Further optimization and validation are being performed in cooperation with the Heart and Diabetes Centre North Rhine-Westphalia.

Numerical Washout Study of a Pulsatile Total Artificial Heart

“…The housing and the end of the membrane were constrained from all movement. In order to ensure a passive filling of the pump chamber and avoid atrial wall suction during diastole, the membrane is not bonded to the pusher plate (21). This results in a sinusoidal buckling of the membrane and a separation from the plate.…”

Controlling the flow balance: In vitro characterization of a pulsatile total artificial heart in preload and afterload sensitivity

“…1,2 For several decades, the research on an artificial heart replacement has been carried out at the Helmholtz Institute in Aachen. [3][4][5] The development of a patented linear actuator formed the basis for the TAH ReinHeart. [6][7][8] The TAH replaces the function of the natural heart and is implanted as an orthotopic heart replacement with complete excision of both ventricles.…”

“…A total artificial heart (TAH) as bridge or alternative therapy to transplantation is an emerging option for the treatment of irreversible biventricular heart failure, partly inevitable due to the mismatch between organ donations and demand 1,2 . For several decades, the research on an artificial heart replacement has been carried out at the Helmholtz Institute in Aachen 3‐5 . The development of a patented linear actuator formed the basis for the TAH ReinHeart 6‐8 .…”

Validation of the electromagnetic design of a total artificial heart under physical load conditions

“…An overview of the position of the components within the human body is shown in Figure 1. Previous work indicates that for destination therapy a minimum durability of five years is required (Kwant et al , 2007) but difficult to be achieved in gear based drives as maintenance is not possible (Kwant, 2007). Thus, we propose a linear direct drive to actuate the TAH as it comprises a minimum of wear prone components.…”