Coronary Physiology Assessment with FFR and iFR
How pressure-wire measurements help determine whether a coronary narrowing limits blood flow and may benefit from treatment.
FFR and iFR are pressure-wire measurements used during coronary angiography to assess whether an intermediate coronary narrowing significantly restricts blood flow. They complement the angiographic image and can prevent treatment decisions based only on the visual percentage of stenosis.
How It Is Used
A thin pressure wire is passed across the lesion. FFR is measured during maximal hyperaemia, commonly produced with adenosine; iFR is measured during a specific resting phase and usually does not require hyperaemia. Common decision thresholds are interpreted together with symptoms, lesion location, vessel territory and the overall clinical setting.
Benefits and Limitations
Physiology-guided assessment can identify lesions that may safely remain on medical treatment and those more likely to benefit from revascularisation. Results may be less straightforward in acute infarction, severe microvascular dysfunction, serial lesions or diffuse disease. Pressure-wire data do not replace clinical judgement or intravascular imaging when anatomy needs clarification.
The small procedural risks are discussed as part of coronary angiography consent.
Patient Selection and Procedural Planning
The procedure is considered only when the expected diagnostic or therapeutic benefit is meaningful for the individual patient. Anatomy, prior imaging, symptoms, rhythm or haemodynamic findings, kidney function, bleeding and vascular risk, medicines and reasonable alternatives are reviewed before consent.
Technical Goals and Limitations
Procedural success requires a defined endpoint, but an immediate technical result does not guarantee permanent symptom relief or eliminate the underlying cardiovascular disease. Complex anatomy, previous procedures and associated disease can change technique, success probability and complication risk.
Risks and Safety
Potential risks vary by procedure and may include bleeding or vascular injury, cardiac perforation, rhythm or conduction disturbance, contrast or kidney effects, stroke, infection and the need for urgent additional treatment. The treating team explains the risks that are specifically relevant to the planned approach.
Recovery and Follow-up
Written instructions should cover access-site or wound care, medicines, driving, work, physical activity and warning signs. Follow-up confirms the procedural endpoint, symptom response and any required imaging or rhythm monitoring. Never stop antithrombotic or rhythm medicine without a procedure-specific plan.
Questions to Ask Before the Procedure
- What precise problem is the procedure intended to solve?
- What alternatives are reasonable in my situation?
- What is the expected success rate and the most relevant personal risk?
- What follow-up and medicines will be needed afterwards?
Medical Information Note
This information supports, but does not replace, the individual consent discussion with the treating cardiovascular team.