Research Project
7908461
DESCRIPTION (provided by applicant): Counterpulsation with an intra-aortic balloon pump has been widely and successfully used as a short term treatment for both acute and chronic cardiac dysfunction. SCR (Louisville, KY) is developing a novel chronic, implantable counterpulsation device (CPD) to treat late stage HF patients. The CPD is a 32-ml stroke volume polyurethane-lined blood chamber designed to fit comfortably in a subcutaneous pocket on the right anterior chest. The blood pumping chamber is connected to the systemic circulation by a short graft anastomosed to the subclavian artery. The CPD is connected to a small, wearable pneumatic driver via a percutaneous drive line. The CPD fills with blood during native heart systole lowering ventricular workload, and ejects during diastole augmenting myocardial and end-organ perfusion. Previous NIH funding has been received for development of both the blood pumping chamber and the portable driver. The timing of ejection from the pumping chamber was synchronized with EKG signals from epicardial leads, which complicated the surgical procedure. To simplify the implant operation, SCR has developed prototype CPD with integrated subcutaneous leads that are ready for in vivo testing. The objective of this proposal is to determine if the CPD with integrated EKG leads placed in the subcutaneous position will result in a robust, durable signal and allow for ideal timing of device filling and ejection. In Specific Aim 1, standard laparoscopic instruments will be used to place subcutaneous EKG leads. The main goals of this aim are twofold: 1) to demonstrate that we are able to deliver subcutaneous EKG leads and show that they do not migrate, 2) to determine which EKG lead configuration results in the best R wave detection. In Specific Aim 2, we will perform full system implants to evaluate the subcutaneous leads in a chronic bovine model. Lead position will be determined in Specific Aim 1. The data from the subcutaneous EKG leads will be used to time device ejection and compared to simultaneous data obtained from epicardial leads. Treadmill exercise testing will be performed to ensure that motion and muscular activity do not interfere with EKG signaling. Strict criteria for determining if the subcutaneous lead configurations are acceptable are outlined. If successful, in Phase 2 we will perform long-term GLP animal implants with the integrated system in preparation for a clinical investigational device exemption (IDE) study. PUBLIC HEALTH RELEVANCE: SCR, Inc. (Louisville, KY) is developing a long-term counterpulsation device (CPD) to treat early stage heart failure patients. The CPD has been developed for superficial implantation without the need to enter the chest and a portable pneumatic driver that the patient can carry restores mobility.
