The purpose of this study is to evaluate coronary artery and peripheral vein vascular endothelial profiles in patients with ischemia with non-obstructive coronary arteries (INOCA) who undergo coronary function testing (CFT). The aims are: (1) Evaluate coronary artery endothelial profiles and associations with coronary microvascular dysfunction (CMD) in INOCA. (2) Assess brachial vein endothelial cell profiles in patients with INOCA and associations with CMD, and (3) Characterize relationships between endothelial signatures and anginal symptoms, functional status, and physical activity at baseline and 1-year follow-up.

Inclusion Criteria:

1. Adult age ≥18 years referred for clinically indicated coronary angiography
2. Chronic coronary disease or potentially ischemic symptoms as the indication for coronary angiography
3. Possible or suspected ischemia with non-obstructive epicardial coronary arteries (INOCA)

Exclusion Criteria:

Clinical (Pre-Cath) Exclusion criteria:

1. Anemia (hemoglobin <9 mg/dl)
2. Severe valvular heart disease
3. Acute myocardial infarction within 30 days
4. Severe valvular heart disease
5. New York Heart Association (NYHA) Functional Class III or IV heart failure
6. Hypertrophic obstructive cardiomyopathy or severe left ventricular hypertrophy
7. Pregnancy (because of potential exercise/activity limitations and symptom changes)

Adult men and women age ≥18 with suspected INOCA who are planned to undergo clinically indicated coronary function testing.

The de-identified participant data from the final research dataset will be shared upon reasonable request beginning 9 to 36 months after publication or as required by a condition of awards or supporting agreements, provided the requesting investigator executes a data use agreement with NYU Langone Health. This instance of data sharing will also require separate IRB review as well as review from NYU Langone's Data Sharing Strategy Board (DSSB). Requests should be directed to nathaniel.smilowitz@nyulangone.org. To gain access, data requestors will need to sign a data access agreement.

Beginning 9 months and ending 36 months following article publication or as required by a condition of awards and agreements supporting the research.

The investigator who proposed to use the data will be granted access upon reasonable request. Requests should be directed to nathaniel.smilowitz@nyulangone.org. To gain access, data requestors will need to sign a data access agreement. This instance of data sharing will also require separate IRB review as well as review from NYU Langone's DSSB. Study data will also be submitted to publicly available databases. NHLBI BioData Catalyst (BDC) will provide long-term access to de-identified dataset(s). RNA sequencing data will be deposited into the NCBI Gene Expression Omnibus (GEO) database, a public functional genomics data repository. Data will be made available at the time of associated publication, as per NIH policy.