Phase 4 Study to Demonstrate Prognostic Usefulness of AdreView™ Scintigraphy for Identifying Subjects With Heart Failure Who Will Experience Death During 60 Months Follow-up.

Inclusion Criteria: * The subject was a HF subject who had signed informed consent for MBG311 or MBG312. * The subject was administered AdreView™ in MBG311 or MBG312. * The subject completed the late planar imaging assessments (at a minimum) required by the protocols for MBG311 and MBG312, and those images were read and judged diagnostic by at least 2 blinded readers. * In addition, all subjects must meet 1 of the following 3 inclusion criteria. * If the subject can be located, he/she provides informed consent to allow the investigator access to medical records and/or gives permission for the investigator to speak to treating physicians. * If the subject can be located and he/she declines to provide informed consent, the IRB/EC provides a waiver of consent to allow the investigator to record that the subject is alive. * If the subject cannot be located, the IRB/EC provides a waiver of consent to allow the investigator to access available medical records for care provided subsequent to last date of subject participation in MBG311, MBG312, and/or MBG313 and/or to allow collection of data from publicly available sources. Exclusion Criteria: * The subject withdrew or was withdrawn from MBG311 or MBG312 because of a protocol violation. * The subject underwent heart transplantation during MBG311, MBG312, or MBG313. * The subject was recorded to have died during MBG311, MBG312, or MBG313. * The subject voluntarily withdrew from MBG311, MBG312, or MBG313, and the IRB/EC has not provided a waiver to allow recording of subject survival status in such an instance. * The subject cannot be located, cannot be contacted, and no information can be found to establish survival status beyond the date of last contact in MBG311, MBG312, or MBG313, including information available as a result of an IRB/EC-approved waiver.