Breathing-Maneuver-Induced Myocardial Oxygenation Reserve Validated by FFR (B-MORE)

Who May Qualify: Healthy Participants - Age: \> 40y - No known current or pre-existing significant medical problems that would affect the cardiovascular or respiratory system. CAD Patients - Age \> 18 y - Indication for invasive coronary angiography based on symptoms and a test positive for inducible coronary ischemia, or previous coronary angiography. Who Should NOT Join This Trial: ALL participants: - General MRI contraindications: Pacemakers, defibrillating wires, implanted defibrillators, intracranial aneurysm clips, metallic foreign bodies in the eyes, knowledge or suspicion of pregnancy. - Consumption of caffeine (coffee, tea, cocoa, chocolate, "energy drink") during the 12 hours prior to the exam. - Regular nicotine consumption during the last 6 months. Patients only - Vasoactive medication (e.g. nitro) during the 12 hours prior to the exam Contraindications to adenosine (2nd or 3rd A-V block, sinus node disease, asthma, bronchoconstrictive diseases). - Acute Coronary Syndrome (ACS), or previous Coronary Artery Bypass Surgery - Previous myocardial infarction within 1 month - Clinically unstable condition - Significant or uncontrolled arrhythmia Always talk to your doctor about whether this trial is right for you.