Mechanisms Behind Microvascular Dysfunction in INOCA

Inclusion Criteria: Only for angina patients: Have CMD, defined as myocardial bloodflow re-serve (MBFR) \< 2.5 or hyperemic myocardial blood flow (hMBF) \< 2.3ml/g/min Exclusion Criteria: * Females of childbearing potential (defined as a premeno-pausal female capable of becoming pregnant). The female patient must either be postmenopausal, defined as amen-orrhea for at least 1 year, or surgically sterile * Heart failure, defined as left ventricular ejection fraction of less than 40% * Uncontrolled hypertension defined as blood pressure above target 140/90 for all * Co-morbidity resulting in \<1 year expected survival * Considered by the investigator, for any reason, to be an unsuitable candidate for the study. * Unable or unwilling to exercise, e.g. due to arthritis or injury\* * Already are regularly physically active and/or have a maximal oxygen uptake \>45 ml/kg/min * The subject has a known allergy to either: norepinephrine, adenosine, ketorolac, and or ascorbic acid (vitamin C).