Abstract 13767: Development of a Long-Term Superficial Device for Partial Circulatory Support
Background: We have developed a circulatory support device (Symphony) that is placed with a minor operation and provides synchronous, partial circulatory support. Potential advantages include: 1) a less invasive operation, 2) may allow implants in less ill patients and thereby promote heart recovery, 3) improved hemodynamics may allow for better tolerance of HF meds, 4) does not preclude use of more invasive operations (sternotomy), 5) simplified device design for complete hemocompatability and, 6) cost benefits. Previous studies showed efficacy. We present our recent pre-clinical GLP implants prior to FIM clinical trials.
Methods: The Symphony is a counter-pulsation device with a 30 ml pumping chamber that is sewn via a short graft to the subclavian artery. Blood is removed from the artery during ventricular systole to provide workload reduction and returned during diastole to augment perfusion. The device is positioned above the pectoralis muscle similar to a pacemaker. To achieve hemcompatibility the device has tangential inflow that creates continuous washing with a shifting vortex to prevent stasis, no objects (valves, impellers) in blood path, and a single moving membrane. In a large animal model under GLP guidelines, the device was sewn to the carotid artery with superficial placement in the neck for 30 days of continuous , partial support (n=6).
Results: All animals were successfully supported without device malfunction, hemolysis, impaired end-organ function,device-related infection, or blood transfusion. At explant, all devices demonstrated excellent hemocompatibility with absence of deposits on all blood contacting surfaces (pumps and grafts). There was no evidence of thromboembolism at necropsy or histology exam.
Conclusions: We have demonstrated excellent hemocompatibilty and device function. This is the first long-term circulatory support device that can be placed without the need for a major operation. The limited operation and use of synchronized partial support may increase the incidence of myocardial recovery, enable optimal titration HF meds and may expand the role of mechanical circulatory support to less ill patients. Device and implantation cost are likely to be significantly less than with currently approved devices.
- © 2011 by American Heart Association, Inc.