The overall objective of this multi-center registry is to identify specific phenotypes of INOCA with both an anatomic evaluation (coronary angiography and intravascular imaging) and physiologic assessment with the Abbott Coroventis Coroflow Cardiovascular System, and to determine long-term outcomes.

This is a prospective, multicenter, registry of stable patients with ischemia and no obstructive coronary artery disease (INOCA) evaluated by coronary angiography, intravascular imaging, and physiologic measurements obtained on the Coroventis Coroflow Cardiovascular System.

The Coroventis Coroflow Cardiovascular System and PressureWire™ X Guidewire (Abbott, Abbott Park, IL) are a device combination consisting of a physiology wire with wireless transmitter (Wi-Box), CoroHub Receiver, and CoroFlow Software. The PressureWire™ X guidewire is a hydrophilic-coated wire with pressure and temperature sensors that is capable of measuring physiologic indices including fractional flow reserve (FFR), resting full cycle ratio (RFR), coronary flow reserve (CFR), and the index of microcirculatory resistance (IMR). The guidewire wirelessly transmits pressure and temperature data via the Wi-Box to the CoroHub Receiver and CoroFlow Software, which is a software interface designed to display pressure measurements, thermodilution curves, and physiologic indices. This registry will enroll 500 subjects at up to 10 sites in the United States that use the Abbott Coroventis Coroflow Cardiovascular System.

The overall objective of this multi-center registry is to identify specific phenotypes of INOCA with both an anatomic evaluation (coronary angiography and intravascular imaging) and physiologic assessment with the Abbott Coroventis Coroflow Cardiovascular System, and to determine long-term outcomes. Specific goals include:

• Describe the prevalence of the following INOCA phenotypes: coronary microvascular dysfunction (CMD), vasospastic angina, mixed CMD/vasospastic angina, other disorders of coronary physiology, and non-cardiac chest pain;
• Characterize the burden of epicardial coronary artery atherosclerosis and myocardial bridging (MB) by angiography and intracoronary imaging (intravascular ultrasound or optical coherence tomography) in patients with INOCA;
• Characterize the natural history and outcomes of patients with INOCA and determine variables associated with major adverse cardiovascular events

Inclusion Criteria:

• Suspected ischemic heart disease and is referred to undergo clinically indicated invasive coronary angiography
• No obstructive coronary artery disease (CAD) as defined by operator visual assessment with (1) angiographically normal coronary arteries OR (2) non-obstructive CAD with angiographic stenosis < 50%, or greater than or equal to 50 but < 70% with FFR greater than or equal to 0.81 or RFR greater than or equal to 0.90
• Willing to comply with specified follow-up evaluations. The participant or legally authorized representative has been informed of the nature of the study, agrees to its provisions, and has been provided written informed consent approved by the appropriate Institutional Review Board (IRB) or Ethics Committee (EC)

Exclusion Criteria:

• Pregnant or nursing
• Any myocardial infarction at index presentation or within 90 days prior to enrollment, defined as any electrocardiogram diagnostic for myocardial infarction OR elevation in serum troponin greater than the upper limit of the site-defined reference range
• Known left ventricular ejection fraction < 50% or cardiogenic shock requiring pressors or mechanical circulatory assistance (e.g., intra-aortic balloon pump, left ventricular assist device, other temporary cardiac support blood pump)
• Renal insufficiency, defined as estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m2 (by the Modification of Diet in Renal Disease equation) or dialysis at the time of screening
• Prior percutaneous coronary intervention
• Planned percutaneous coronary intervention (PCI)
• Prior coronary artery bypass graft surgery
• Prior ST-elevation myocardial infarction
• History of hypertrophic cardiomyopathy
• History of infiltrative heart disease (e.g., cardiac amyloidosis)
• New York Heart Association Class IV congestive heart failure
• Severe mitral regurgitation
• Severe aortic stenosis
• Severe pulmonary hypertension (Mean pulmonary artery pressure greater than or equal to 35mmHg or echocardiographic right ventricular systolic pressure greater than or equal to 60mmHg)
• Known history of unrepaired or repaired congenital heart disease
• Past or pending heart transplant, or on the waiting list for organ transplant
• Known other medical illness or known history of substance abuse that may cause non-compliance with the protocol, or is associated with a life expectancy of less than 1 year
• Current or planned participation in a study of an investigational therapy
• Angiographic stenosis in any major epicardial vessel ≥ 70% by visual estimate
• Angiographic stenosis in any major epicardial vessel greater than or equal to 50% and < 70% by visual estimate with FFR less than or equal to 0.80 or RFR less than or equal to 0.89

Adults referred to the catheterization laboratory for evaluation of suspected ischemic heart disease, and who are deemed to have non-obstructive coronary artery disease based on coronary angiography or non-ischemic fractional flow reserve (FFR) or resting free cycle ratio (RFR).