Using iFR measurements to improve bypass surgery outcomes

Long-term Graft Patency Outcomes of LIMA-LAD Post-CABG Surgery Based on iFR Measurements.

Imperial College Healthcare NHS Trust · NCT04014140

This study is testing if measuring blood flow in the heart using a special technique can help improve the success of bypass surgery for people with multiple blocked arteries.

Quick facts

Study typeObservational
Enrollment100 (estimated)
Ages25 Years to 80 Years
SexAll
SponsorImperial College Healthcare NHS Trust (other)
Locations1 site (London, Greater London)
Trial IDNCT04014140 on ClinicalTrials.gov

What this trial studies

This observational study aims to evaluate the correlation between intra-coronary physiology, specifically instantaneous wave-free ratio (iFR) measurements, and the patency of bypass grafts in patients undergoing coronary artery bypass grafting (CABG) surgery. Patients with multi-vessel coronary artery disease will have iFR measurements taken during pre-operative angiography, followed by CABG surgery. The study will assess early graft failure through clinical symptoms and echocardiography at 3 months, with graft patency evaluated via CT coronary angiography at 12 months. The goal is to determine if iFR can provide better outcomes compared to traditional angiographic assessments.

Who should consider this trial

Good fit: Ideal candidates are patients aged 25 to 80 years with multi-vessel coronary artery disease scheduled for isolated first-time elective CABG surgery.

Not a fit: Patients requiring emergency CABG surgery, those with an ejection fraction of 40% or less, or severe valvular heart disease may not benefit from this study.

Why it matters

Potential benefit: If successful, this approach could lead to improved graft patency and better long-term outcomes for patients undergoing CABG surgery.

How similar studies have performed: While the use of iFR has shown success in percutaneous interventions, its application in CABG has not been extensively validated, making this a novel approach.

Eligibility criteria

Show full inclusion / exclusion criteria
INCLUSION CRITERIA

1. Age of 25 to 80 years of age
2. Willing to participate and able to understand, read and sign the informed consent form (ICF) before standard of care elective CABG surgery
3. Undergoing isolated first-time elective CABG surgery
4. Available pre-operative angiography data with iFR measurements done during the pre-operative angiography

EXCLUSION CRITERIA

1. Emergency CABG surgery
2. Ejection Fraction≤ 40%
3. Severe valvular heart disease

Where this trial is running

London, Greater London

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Ischaemic Heart Disease, Coronary Artery Disease, Coronary Stenosis, Instantaneous wave-free ratio, Coronary Artery Bypass Grafting

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.