Heart failure (HF) is a major health problem in the US and worldwide. Over 100,000 people in the US are diagnosed with end stage HF annually. Heart transplantation is performed in only 2% of these cases due to lack of available donor hearts. Mechanical left ventricular assist devices (LVADs, a type of artificial heart) can allow patients with severe HF to live a productive and relatively comfortable life if cardiac transplantation is not possible for them. Our goal is to improve the treatment of severe heart failure by developing and commercializing the TORVAD" system, which is a valveless, pulsatile LVAD. The currently available LVADs use rotary, turbine-like pumps that support the circulatory system with a steady, pulse-free stream of blood, which typically means the patient no longer has a pulse. It is then difficult or impossible to measure their blood pressure and also difficult o optimize medications for their heart failure. Additionally this pulseless blood flow induces abnormal blood vessel formation in the gut and brain that can lead to serious bleeding complications. The focus of this project is to experimentally test the clinical readiness of our pulsatile LVAD and develop unique control features that will significantly improve the care of patients with heart failure. The specific design will feature a dual piston, pulsatile pump that activates simultaneously with the native heart activity, senses blood pressure, and permits remote patient monitoring, to produce an improved patient sense of well-being and safety with significantly reduced complications. Previously, in collaboration with the University of Texas Health Science Center - Houston, a series of bench top and animal studies successfully demonstrated the feasibility and superiority of synchronized pulsatile flow as compared to continuous flow support. In Phase I we will (1) Characterize hydraulic pump performance and assess potential for blood damage by the pump in bench top tests;(2) Optimize the pump control module and means for remote patient monitoring;(3) Develop blood pressure sensing capability by the pump and (4) Conduct three short-term animal experiments to demonstrate basic hydraulic performance, biocompatibility, and synchronization with the heart cycle including automatic adjustments to pump function during irregular heart rhythms and major changes in heart rate. In Phase II we will demonstrate system safety and endurance, and will (1) Conduct accelerated durability tests on critical pump subsystems;(2) Perform 180-day durability tests on two pumping systems operating in bench top simulated circulatory loops;(3) Perform five short-term animal experiments to demonstrate optimal surgical implantation and de-airing procedures, optimal hemodynamic performance, ECG sensing and synchronicity, suction detection, pump auto-regulation, pressure sensing and control;and (4) Conduct three 30-day chronic animal tests to assess physiological performance, biocompatibility, device safety, durability, blood cell damage, and risk of stroke. We believe that our technology has the potential to improve patient quality of life while minimizing complications compared to currently available LVADs.

Public Health Relevance

We are developing an innovative blood pumping technology with the potential to advance the clinical treatment of severe heart failure, a condition that is experienced by over 100,000 US patients. We aim to conclusively demonstrate that our TORVAD system restores optimal blood flow, reduces complications, and possesses the needed endurance to effectively treat heart failure and potentially increase cardiac recovery rates, promoting the use of implantable blood pumps to treat earlier stages of the disease.

National Institute of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
Small Business Technology Transfer (STTR) Grants - Phase II (R42)
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Special Emphasis Panel (ZRG1-SBIB-V (12))
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Baldwin, Tim
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Windmill Cardiovascular Systems, Inc.
United States
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