The CorWave LVAD - Synchronized Pulsatility with Improved Hemodynamics

Abstract

<h3>Purpose</h3> The CorWave LVAD employs a novel wave membrane technology to generate low shear blood propulsion that can produce a physiologic pulse. Herein, we report the results of in vitro and in vivo testing of pumps for hemodynamics, hemocompatibility, and durability. <h3>Methods</h3> Computational simulations were used to optimize shear stress in the blood flow path < 9 dyn/cm², the maximum that occurs in normal physiology, while improving hydraulic performance. Prototype pumps confirmed the hydraulic and hemocompatibility results with the optimized flow paths. Pulsatility control algorithms were tested for sensorless synchronization with the native left ventricle (LV), arrhythmia detection, and pulse pressure (PP) amplitude generation in 3 settings: 1) In vitro mock circulation loops (MCLs), 2) acute implants in sheep with induced heart failure (HF), and 3) chronic implants in healthy sheep. An adaptive pump control program was developed to adjust the pump operating settings in response to changes in pre-load or after-load. Pump durability was assessed by continuous operation in MCLs. <h3>Results</h3> During implants in sheep with HF (EF 20-40%), the cardiac output increased from a baseline of 2-3 LPM to 5-6 LPM with the CorWave LVAD operating in continuous and pulsatile modes. The pulsatility algorithm successfully synchronized to > 95% of LV contractions during acute and chronic implants without the use of sensors. The algorithm identified arrhythmia conditions for safe transitions to non-synchronized operating modes. CorWave pumps generated PPs > 30 mmHg in vitro, and > 25 mmHg in vivo, where PP was constrained due to limitations of the animal model. In vivo, the adaptive pump control program successfully adjusted the pump operating points in response to hemodynamic challenges. The pump hemocompatibility was confirmed by low hemolysis and preservation of von Willebrand Factor function during chronic implants. Three pumps have completed 1 year durability tests, with 7 additional devices running beyond 6 months. We are building lifecycle test stands to commence multiple year durability tests to support clinical trial submissions. <h3>Conclusion</h3> The CorWave LVAD has achieved milestones for pulsatile hemodynamic performance, hemocompatibility, and durability, demonstrating substantial progress towards clinical readiness, providing a credible alternative to rotary blood pumps.