This study is to be performed at two clinical sites where patients received CardioGen-82 during the time period January to June, 2011 and where patients were scanned chronologically near to the index patients (2 days before or after). Of these, it is planned that at least 30 patients will be entered in this trial. Index patient is the term applied to individuals who had radiation spectra indicative of Sr-82 and Sr-85 detected by hand-held survey meters.

This clinical study protocol will use a three tier approach consisting of the following examinations:

• Patient examination with Survey Meter: The patient will first be tested at the clinical sites using a survey meter. In those patients whose radiation count is ≥ 2 times above background count using a standard survey meter, the presence of Sr-82 and/or Sr-85 will be assessed through a quantitative reading from a calibrated portable isotope identifier.
• Patient examination with Portable Isotope Identifier: This examination will be done by use of a portable isotope identifier, which will be supplied by the Sponsor to the study sites. An assessor, independent to the study site and will perform the examination. In those patients whose radiation count is ≥ 2 times above background count using a standard survey meter, the presence of Sr-82 and/or Sr-85 will be assessed through a quantitative reading from a calibrated portable isotope identifier. The reading will be forwarded along with the date of the reading, the date of the patient's CardioGen-82® scan, and the total dose of CardioGen-82® administered to the patient, to an independent medical expert, independent to the study site, who will back-calculate an estimated dose of Sr-82 and/or Sr-85 from these data.
• Patient examination at Oak Ridge National Laboratory: Any patient whose estimated dose of Sr-82 exceeds the specified limit of 0.02 microcuries per mCi Rb-82 administered, and/or whose estimated dose of Sr-85 exceeds the specified limit of 0.2 microcuries per mCi Rb-82 administered, will be asked to travel to Oak Ridge National Laboratory in Tennessee, for accurate whole body scanning. Scan data from Oak Ridge National Laboratories will be analyzed by one or more independent medical experts to accurately back-calculate exposure to Sr-82 and/or Sr-85, and to estimate health hazard for the patient.

Inclusion Criteria:

• Male or female;
• Gave informed consent to participate in the study;
• Received CardioGen-82 that has been eluted from the generator in close proximity (2 days before or after) the index patients.

Exclusion Criteria:

-Any patient previously enrolled in and completed this study.

The study population would come from the two sites who administered CardioGen-82® to the index patients. Each site that agrees to participate will enroll patients administered CardioGen-82 2 days before and 2 days after the use of that generator.