Heart failure has become one of the major epidemics of the modern era. Despite optimal standard drug therapy, the prognosis of patients with heart failure remains poor. Patient with Heart Failure are prone to have "dyssynchrony" which means that there are electrical disturbances that cause the heart to pump blood in an inefficient way. Ventricular dyssynchrony has been associated with increased mortality in patients with heart failure. Based on these observations, techniques have been developed to correct dyssynchrony. The investigators propose to investigate the change of dyssynchrony in relation to intravascular volume status and exercise in heart failure patients. The investigators also propose to examine dyssynchrony in the setting of acutely decompensated heart failure. The change in dyssynchrony will be followed to examine if it translates into clinical significance.