For enrollment into the prospective cohort for Outcome 3.  Inclusion Criteria:  Willing to adhere to the study protocol Able to provide written consent English or Spanish speaking Adult, defined as 18 years or older Primary reason for presentation to the ED is dyspnea ED physician is considering a diagnosis of HF, defined by ordering a NP test and/or a chest x-ray  Exclusion Criteria:  History of end-stage renal disease for which hemodialysis is needed Dyspnea due to primary presentation of an acute coronary syndrome or trauma