Impella Reverse Remodeling in End-Stage Heart Failure

Inclusion Criteria: * Age 18 years or older * Dilated cardiomyopathy (LVEDD \> 5.5 cm and LVEF \<25%) * Indication for temporary mechanical circulatory support therapy with Impella 5.5 LVAD as a bridge to transplant or bridge to transplant decision based on treating physician's discretion Exclusion Criteria: * Intra-aortic balloon pump (IABP) use for more than 7 days at the time of Impella 5.5 implantation * Percutaneous mechanical circulatory support device, extracorporeal membrane oxygenation (ECMO) or paracorporeal ventricular assist device (VAD) support prior to Impella 5.5 implantation * Congenital heart disease * Restrictive or hypertrophic Cardiomyopathy including hypertrophic obstructive cardiomyopathy (HOCM) Amyloidosis, and Sarcoidosis * Evidence of acute myocarditis by endomyocardial biopsy * Prior heart transplantation * Mechanical aortic / mitral valve * Patient with known aortic diseases such as Marfan-Syndrome, Morbus Erdheim-Gsell or others * Left Ventricular thrombus * Left Ventricular rupture * Cardiac tamponade * Presence of an Atrial or Ventricular Septal Defect * Severe right ventricular (RV) Failure requiring mechanical RV support * Severe peripheral vascular disease precluding placement of the Impella System * Recent stroke resulting in significant neurological deficit * Hypercoagulable disease precluding device implantation * Severe thrombocytopenia (\<50,000) * Contraindication to anticoagulation * Suspected or known pregnancy or lactating women * Subject belongs to a vulnerable population