This is a prospective, observational, single-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 in Multi-Vessel Disease.

Inclusion Criteria:

• >18 years of age.
• Patients with stable angina or unstable angina or NSTEMI, with at least 1 stenoses ≥ 50% in two main vessels (LAD, LCX and/or RCA) each and in whom invasive FFR is being assessed at these stenoses.
• Patients undergoing invasive FFR with Adenosine, ATP or Papaverine used as hyperemic stimulus.
• Written, informed consent.

Exclusion Criteria:

• Contraindication for FFR examination or administration of vasodilators.
• Clinical presentation of an acute infarct (STEMI) or presented with STEMI in past year.
• CTO in a target vessel.
• Prior CABG, valvular surgery, TAVI/TAVR, or heart transplantation.
• 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 lesions involve Left Main (stenosis ≥50%.)
• In-stent restenosis in a target vessel.
• Heavily diffused atherosclerosis diseases defined as the presence of diffuse, serial gross luminal irregularities present in the majority of the coronary tree.
• Target coronary vessels are supplied by major collaterals.
• Lesion is in ectatic segment which includes dilatation in diameter at least 1.5 times that of the adjacent normal coronary artery.
• Coronary angiograms not acquired per instructions as defined in the Study Protocol.

Subjects with stable angina, unstable angina or NSTEMI who are referred to coronary angiography, have multi-vessel coronary artery disease and have an invasive FFR measurement at two lesions at minimum. Each subject will undergo both the standard invasive FFRs and the investigational FFRangio.