This is a prospective, observational, multi-center, single-arm, clinical trial designed to assess the efficacy of FFRangio in measuring FFR obtained from angiography compared to Invasive FFR for diagnosing hemodynamically significant coronary stenosis.

Inclusion Criteria:

• Male or female subjects, >18 years of age.
• Patients with stable angina or unstable angina or NSTEMI, and in whom invasive FFR is being assessed in a non-culprit stenosis in at least one coronary artery.
• Subject is undergoing invasive FFR with Adenosine, ATP or Papaverine used as hyperemic stimulus.
• Provides written, informed consent (where required)

Exclusion Criteria:

• Contraindication for FFR examination or administration of vasodilators.
• Subject is presenting with acute infarct (STEMI) OR has documented prior STEMI on same side (right/left).
• CTO in target vessel.
• Prior CABG, heart transplant or valve surgery, or prior TAVI/TAVR.
• Known LVEF ≤45%.
• Arteries supplying akinetic or severe hypokinetic territories if already known based on prior imaging.
• TIMI Grade 2 or lower at baseline.
• Target lesion involves Left Main (stenosis >50%).
• PCI with stent in target vessel in past 12 months, or target vessel involves in-stent restenosis.
• Severe, diffuse disease defined as the presence of diffuse, serial gross luminal irregularities present in the majority of the coronary tree.
• Target coronary vessel is supplied by major collaterals.

Subjects with stable angina, unstable angina or NSTEMI who are referred to coronary angiography and have an invasive FFR measurement with vasodilation in at least one coronary artery. Each subject will undergo both the standard invasive FFR and the investigational FFRangio.