These patients with advanced heart failure are also at the greatest risk for heart failure–related hospitalization

and mortality, with a 1-year mortality rate of at least 10% to 15% 2, 3 and 4. While therapies such as cardiac transplantation or left ventricular assist devices (LVADs) may benefit the subset of this population with end-stage disease defined by the American College of Cardiology/American Heart Association as Stage D heart failure, these measures are generally not indicated for the vast majority of patients with Stage C heart failure (5). Moreover, the small number of available donor organs limits the application of cardiac transplantation, and LVADs are limited by the blood-contacting nature of their design and need for chronic anticoagulation, resulting in significant device-related adverse events of stroke, major bleeding, infection, learn more and device failure (6). Thus, there is an unmet need Protease Inhibitor Library for additional therapies for American College of Cardiology/American Heart Association Stage C and NYHA functional class III and ambulatory functional class IV heart failure patients. One emerging approach to these patients is through the use of chronic ambulatory aortic counterpulsation 7, 8 and 9. Aortic counterpulsation is a well-established

mode of circulatory support that works by reducing left ventricular after-load during systole and augmenting blood pressure and systemic and coronary perfusion during diastole 10, 11 and 12. While the application of aortic counterpulsation in acutely ill patients involves the use of an intra-aortic system (the intra-aortic balloon pump), implantable intra- and extra-aortic counterpulsation systems

have been developed for chronic ambulatory use 13, 14, 15 and 16. One such system, the C-Pulse System (Sunshine Heart, Inc., Eden Prairie, Minnesota), includes a novel implantable, nonobligatory, non–blood contacting Y-27632 2HCl counterpulsation heart assist pump developed for minimally invasive implantation without the need for cardiopulmonary bypass 15 and 16. The C-Pulse System was designed to provide an effective low-risk and low-cost mechanical heart assist device for use in patients with chronic American College of Cardiology/American Heart Association Stage C and NYHA functional class III and ambulatory functional class IV heart failure. The device is designed to be turned off safely or weaned if there is sustained cardiac recovery and similarly, in failure modes, is considered to have a low risk of death or disability, other than the recurrence of heart failure symptoms. No anticoagulants are required, reducing the risk of bleeding complications, and the extravascular nature of the implant mitigates the risk of intravascular thrombus formation, thromboembolism, and blood-borne infection. Preliminary studies suggest that this method of counterpulsation is feasible and safe 15 and 16.