Functional ComprEhensive AssessmenT by IVUS Reconstruction in Patients With Suspected IschEmic Heart Disease (FEATURE)

Functional ComprEhensive AssessmenT by Intravascular UltrasoUnd Reconstruction in Patients With Suspected IschEmic Coronary Artery Disease (FEATURE)

Investigating the diagnostic accuracy of online Ultrasonic Flow Ratio (UFR) assessment to identify hemodynamically significant coronary stenosis in patients with suspected ischemic heart disease using angiography-derived fractional flow reserve (FFR) as a reference standard.

1. Study overview This is a prospective, single-center, observational registry study of patients with suspected ischemic coronary artery disease. The purpose of this registry is to investigate the accuracy of online UFR assessment to identify hemodynamically significant coronary stenosis in patients with suspected ischemic heart disease using angiography-derived FFR as a reference standard.
2. Study population and sample size calculation are based on the diagnostic performance of previous studies, where an accuracy of 92% was found for UFR. Investigators conservatively estimate the diagnostic accuracy of online UFR assessment as 90% for consecutively enrolled patient population, and with a test target value set as 78% at a two-side significance level of 0.05, statistical power as 90%. Considering incomplete FFR/UFR data of 10% at most, a total of 112 patients need to be enrolled.
3. Participant enrollment was completed in November 2024; the study is currently in the follow-up phase with ongoing data collection and analysis.

Inclusion Criteria:

• Subject must be ≥ 18 years
• Patients suspected with ischemic heart disease
• ≥ 1 diseased vessel with angiographic percent diameter stenosis between 40% and 80% in a vessel ≥ 2.5mm by visual estimation
• Target vessels are limited to major epicardial coronary arteries (left anterior descending artery [LAD], left circumflex artery [LCX], right coronary artery [RCA])

Exclusion Criteria:

• Patients with previous coronary artery bypass grafting (CABG)
• Myocardial infarction within 72h of coronary angiography
• Allergy to the contrast agent or adenosine
• Left main coronary artery stenosis ≥ 50%
• Target vessel with in-stent restenosis
• Target vessel with severe tortuosity or angulation
• 100% occlusion of target vessel
• Target vessel spasm or injury
• Target vessel with severe myocardial bridge
• Target vessel with severe thrombosis
• Intravascular ultrasound (IVUS) pullback fails to cover the complete target lesion
• Presence of false lumen at target vessel based on IVUS
• A serum creatinine level >150 umol/l, or a glomerular filtration rate < 45 ml/kg/1.73 m^2
• Heart failure
• Ineligible for diagnostic intervention (IVUS or FFR examination)