Myocardial Perfusion Imaging Galmydar Rest/Stress

Inclusion Criteria: * Male and female, 18-99 years of age and any race; * Have had a prior clinical SPECT or PET MPI positive for ischemia in two myocardial segments and referred for invasive coronary angiography (ICA) or have had a prior clinical SPECT or PET MPI negative for ischemia or healthy adult normal volunteers who are asymptomatic, without history of cardiovascular disease or significant cardiovascular risk factors; Exclusion Criteria: * Inability to receive and sign informed consent; * Percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) within 6-months prior to clinical SPECT or PET or in the intervening days between clinical SPECT or PET and research PET examination; * Participants who have received chemotherapeutic agents within 6 months of enrollment; * Heart failure (left ventricular ejection fraction ≤ 20%); * Known non-ischemic cardiomyopathy; * Inability to undergo pharmacologic stress testing with regadenoson (Lexiscan). Contraindications include: * Symptomatic bradycardia or second to third degree atrioventricular (AV) block; * Pre-existing obstructive lung disease with active wheezing, i.e., COPD, asthma with active wheezing that precludes the safe administration of the pharmacological stress agent according to the approved label; * Uncontrolled and severe hypertension (e.g. systolic blood pressure \>200 mmHg, diastolic blood pressure \>110 mmHg); * Baseline hypotension (e.g. systolic blood pressure \< 90 mmHg, d…