This study hopes to provide significant technical improvement in a Myocardial Blood Flow (MBF) cardiac magnetic resonance (CMR) quantification technique to address challenges and technical limitations for MBF CMR. By developing and validating novel techniques to improve first-pass perfusion (FPP) cardiac MR, we propose to increase diagnostic accuracy by minimizing false positives and false negatives, allow for better evaluation and accurate quantification of total ischemic burden and reduce image and motion-induced artifacts.

The broad, long-term objective of the proposed project is to improve the prognosis of patients with myocardial ischemia caused by coronary artery disease (CAD) or coronary microvascular dysfunction (CMD).

All subjects will receive cardiac MRI scans to diagnose CAD or CMD. MR perfusion scans will be performed twice per subject: once at rest, and once after administration of a pharmacologic stress agent. There will be a >15 minute delay between the two scans. A gadolinium-based contrast agent will be administered during each scan to allow measurement of myocardial blood flow. Once myocardial blood flow is quantified, the measurements will be compared to previous reference measurements (when available) from PET myocardial perfusion imaging in the CAD patient cohort and coronary reactivity testing (CRT) in the CMD patient cohort.

Inclusion Criteria:

• 60 healthy male or female (18 or older) participants
• 110 male or female adults (18 or older) who have undergone clinical myocardial perfusion imaging at CSMC and been diagnosed with Coronary Disease (CAD).
• 50 female adults (21 or older) who have undergone coronary reactivity testing at CSMC and been diagnosed with coronary microvascular disease (CMD).

Exclusion Criteria:

• MR imaging is contraindicated in persons with mechanically, magnetically, or electrically activated implants, such as cardiac pacemakers, neurostimulators, and infusion pumps.
• Persons with ferromagnetic implants and ferromagnetic foreign bodies, such as intracranial, aneurysm clips, shrapnel and intraocular metal chips as these could become dislodged.
• Patients who are pregnant, nursing, implanted with non MR-compatible intrauterine devices (IUD's)
• Persons unable to tolerate MRI imaging secondary to an inability to lie supine or severe claustrophobia.
• Persons who are non-compliant with visit instructions, including inability to lie still, hold breath or follow procedure instructions
• Persons whose renal function test does not meet CSMC standard of care MRI contrast protocol requirements (GFR <45ml/min).
• Persons with stated allergy to animal dander
• acute coronary syndrome or acute myocardial infarction or ongoing myocardial ischemia or ECG evidence of ongoing ischemia;
• patients with concurrent cardiogenic shock or requiring inotropic or intra-aortic balloon support or prior/planned PCI or CABG;
• non-ischemic cardiomyopathy or more than moderate valvular disease;
• contraindication to stress agent (adenosine) including asthma or prior adverse reaction to adenosine
• contraindications for gadolinium contrast;

CMD cohort will enroll female participants only.

• 60 healthy male or female (18 or older) participants
• 110 male or female adults (18 or older) who have undergone clinical myocardial perfusion imaging at CSMC and been diagnosed with Coronary Disease (CAD).
• 50 female adults (21 or older) who have undergone coronary reactivity testing at CSMC and been diagnosed with coronary microvascular disease (CMD).