A Soft Total Artificial Heart—First Concept Evaluation on a Hybrid Mock Circulation

Abstract

The technology of 3D-printing has allowed the production of entirely soft pumps with complex chamber geometries. We used this technique to develop a completely soft pneumatically driven total artificial heart from silicone elastomers and evaluated its performance on a hybrid mock circulation. The goal of this study is to present an innovative concept of a soft total artificial heart (sTAH). Using the form of a human heart, we designed a sTAH, which consists of only two ventricles and produced it using a 3D-printing, lost-wax casting technique. The diastolic properties of the sTAH were defined and the performance of the sTAH was evaluated on a hybrid mock circulation under various physiological conditions. The sTAH achieved a blood flow of 2.2 L/min against a systemic vascular resistance of 1.11 mm Hg s/mL (afterload), when operated at 80 bpm. At the same time, the mean pulmonary venous pressure (preload) was fixed at 10 mm Hg. Furthermore, an aortic pulse pressure of 35 mm Hg was measured, with a mean aortic pressure of 48 mm Hg. The sTAH generated physiologically shaped signals of blood flow and pressures by mimicking the movement of a real heart. The preliminary results of this study show a promising potential of the soft pumps in heart replacements. Further work, focused on increasing blood flow and in turn aortic pressure is required.

Ultrasonic sensor concept to fit a ventricular assist device cannula evaluated using geometrically accurate heart phantoms

“…Anatomically detailed heart phantoms were manufactured using a 3D printing, lost-wax casting technique (26) to mimic the trabeculae carneae, the papillary muscles, and the heterogeneous wall thicknesses (see Figure 2). The silicone casting technique yielded highly elastic, durable heart phantoms consisting of a material that has previously been used to test ultrasonic systems (23,27).…”

“…While porcine models generally perform well for testing hemodynamics; unfortunately, this is not the case for the LV morphology. The trabeculae carneae as well as the papillary muscles need to be replicated more accurately than current existing heart phantoms allow (20)(21)(22)(23)(24), which shows the need for the use of an advanced additive manufacturing technique (25)(26)(27). In the human LV, the ultrasonic beam encounters complex reflection and refraction patterns at the intra-ventricular surface.…”

Modification of silicone elastomers with Bioglass 45S5® increases in ovo tissue biointegration

“…Silicone elastomers are a frequently used material family for the production of medical devices and used in implants, such as pacemakers, breast implants, and artificial blood pumps . The long‐term stability of these implants inside the human body is a crucial factor for their success.…”

Heart Replacement Therapy: Biological, Mechanical or Regenerative?

“…); and class V, artificial organs with natural tissues and cells (hybrid artificial organs). Thus, it would be useful to invest dedicated funds through multidisciplinary research into classes I and V, just to have an "hybrid" concrete long-lasting cardiac replacement solution (14,16,(24)(25)(26).…”

“…In summary, the new medical technology in the current century is that which would be achieved through the cooperation of specialists in traditional mechanical artificial organs and regenerative organ medicine (4,5,13,14,16,(22)(23)(24)(25)(26). If they do not work together, more time, effort, and money are needed to achieve successful "reliable and proper" artificial organs.…”