Inorganic Nitrate as a Treatment for ANOCA: NO-ANOCA

Inclusion Criteria:

* Age ≥18 years.
* Female sex.
* Willing and able to provide written informed consent.
* Signs and symptoms of suspected ischemia prompted referral for further evaluation by cardiac catheterization or CCTA within two years of consent.
* No evidence of obstructive epicardial CAD (stenosis \>50%) of a major epicardial vessel or an FFR ≤0.80 by invasive catheterization or CCTA. Patients who have not undergone cardiac catheterization of CT angiogram within the last 2 years for chest pain can be scheduled for a screening CT angiogram of the coronary arteries to confirm eligibility.
* Impaired coronary flow reserve (cut-off values depending on methodology use between ≤2.0 and ≤2.5 by stress testing PET/CMR or Invasive assessment) or Abnormal index of coronary microcirculatory resistance (e.g., IMR \> 25)
* SGLT2i Naïve

Exclusion Criteria:

* History of non-ischemic cardiomyopathy LVEF \<40% or hypertrophic cardiomyopathy.
* History of congestive heart failure, severe pulmonary disease, liver disease
* History of acute coronary syndrome (ACS) within previous 30 days
* Stroke within the last 180 days or intracranial hemorrhage at any time.
* Severe valvular disease
* Life expectancy \<3 years, due to non-cardiovascular comorbidity.
* Pregnancy or women who are breast-feeding
* Type 1 diabetes mellitus
* Symptomatic hypotension or systolic BP\<95 mmHg on 2 consecutive measurements
* Active malignancy requiring treatment at the time of visit
* Severe (eGFR \<30 mL/min/1.73 m2 by CKD-EPI), unstable, or rapidly progressing renal disease at the time of randomization
* History of recurrent UTI/bladder/kidney infections
* Asthma with ongoing wheezing
* Known or suspected bronchoconstrictive or bronchospastic lung disease (ARDS, emphysema)
* Greater than first degree heart block
* Implanted cardiac device
* Profound sinus bradycardia (heart rates\<40 beats per minute)
* Atrial fibrillation or supraventricular arrhythmias at time of imaging
* Known intolerance of nitrates (other than hypotension)
* History of reaction to iodinated contrast agents
* Any orthopedic, neurological, or other condition that prevents participant from exercising
* Individuals currently taking nitroglycerine (or inorganic nitrates), PDE-5 inhibitors (ex: Cialis, Viagra), and xanthine oxidase inhibitors (ex: Allopurinol)
* Smokers within the last 5 years
* Prisoners
* Cognitively impaired individuals
* Non-English Speaking