The TORVAD(tm) is a unique ventricular assist system that delivers low-shear, synchronous, pulsatile flow. Blood shear due to pumping is minimized by the relatively low speed of pistons supported by hydrodynamic bearings designed to maintain a fixed gap between the piston and torus walls. The TORVAD synchronizes with the heart to preserve aortic valve flow and maintains autoregulation of cardiac output by the Frank-Starling mechanism. The design of the TORVAD also allows for inherent determination of differential pump pressure, without additional sensors, which can be used to manage patient medications and pump flow rates. These advantages have been confirmed in preliminary studies. In vitro tests have demonstrated that the low-shear design preserves high-molecular-weight von Willebrand factor and results in significantly reduced hemolysis as compared to clinically available continuous flow devices. The TORVAD's hematological results are unmatched by any other ventricular assist device. In addition, synchronous hemodynamics have been demonstrated using acute and chronic animal models. These preliminary findings demonstrate that the TORVAD has the potential to reduce bleeding, thrombus formation, and strokes that are associated with the use of other ventricular assist devices. The goal of this project is to bridge the TORVAD from R&D to first-in-human clinical trials by conducting the verification and validation steps necessary to determine the safety of the TORVAD system and to apply for an Investigational Device Exemption (IDE) for an Early Feasibility Study. This will be accomplished as follows: 1) Use previous experience with prototypes to finalize the design, implement design controls, and perform risk analysis on the system; 2) Fabricate and assemble 35 systems for testing; 3) Perform subsystem verification testing; 4) Complete in vitro design evaluation and system performance testing to confirm device performance and reliability; 5) Conduct in vivo acute and chronic animal experiments to demonstrate device safety; and 6) Apply for an IDE for an early feasibility study.
Due to the lack of donor hearts, an ever-growing number of patients receive a ventricular assist device each year. The TORVAD(tm) has the potential to address common complications associated with existing ventricular assist devices due to reduced blood trauma made possible by a unique low-shear piston pumping technology. This provides the valveless pulsatile flow TORVAD with the potential to improve patient management and reduce incidence of bleeding, neurological dysfunction, and strokes. (End of Abstract)
| Gohean, Jeffrey R; Larson, Erik R; Hsi, Brian H et al. (2017) Scaling the Low-Shear Pulsatile TORVAD for Pediatric Heart Failure. ASAIO J 63:198-206 |
