What are the limitations of the ffr fractional flow reserve ?

While the ffr fractional flow reserve is highly validated, it should not replace clinical judgment. OpiCalc provides the latest evidence-based limitations for the ffr fractional flow reserve to ensure safe bedside use and optimal diagnostic accuracy.

How does the ffr fractional flow reserve compare to other Cardiovascular scores?

The ffr fractional flow reserve is a gold-standard diagnostic tool. OpiCalc provides side-by-side clinical guidance to help clinicians choose the most specific evidence-based tool for their patient's presentation.

Is the ffr fractional flow reserve free to use?

Yes. OpiCalc provides the ffr fractional flow reserve completely ad-free and optimized for mobile bedside use, ensuring you can calculate medical risk swiftly and without distraction.

FFR (Fractional Flow Reserve)

FFR (Fractional Flow Reserve): Pressure-wire derived index to assess functional significance of coronary lesions.

Pressure Measurements (at maximal hyperaemia)

Distal Coronary Pressure — Pd (mmHg)

Aortic Pressure — Pa (mmHg)

Formula

FFR = Pd / Pa

Guidelines & Evidence

Clinical Details

Section 1

When to Use

Functional assessment of coronary lesion severity during angiography

Decision-making: proceed with PCI vs. defer in intermediate stenosis

Multivessel disease triage (defer non-culprit lesions if FFR >0.80)

Guidance for staged revascularization strategy

≥50% but <90% angiographic stenosis requiring physiologic assessment

Key Points

FFR 0.75–0.80: borderline lesions benefit from serial assessment or iFR

FFR-guided PCI reduces MACE vs. angiography-only guided strategy

ESC/AHA recommend FFR for intermediate coronary lesions

Requires adenosine hyperaemia or equivalent stress; adenosine-free alternatives (iFR, RFR) emerging

Section 2

Formula & Logic

Formula

FFR = Pd/Pa at maximal hyperaemia Pd = distal coronary pressure (beyond lesion) Pa = aortic pressure (proximal) Normal FFR = 1.0 (no pressure drop) FFR <0.80 = functionally significant lesion (ischaemic)

Interpretation

FFR Value	Clinical Significance	Recommendation
≥0.80	Not ischaemic	Defer PCI; medical therapy
0.75–0.80	Borderline	Consider serial or iFR
<0.75	Ischaemic	PCI recommended
<0.50	Severe ischaemia	PCI strongly indicated

Section 3

Pearls/Pitfalls

Technical Pearls

Adenosine dose: 140–180 µg/kg/min IV (preferred); or 12–18 µg IC per vessel

Ensure true hyperaemia by observing ≥50% HR increase or equalization of distal/aortic pressures

Avoid nitroglycerin interference; check baseline Pd/Pa ratio pre-hyperaemia

Serial stenosis: pullback pressure tracing identifies contribution of each lesion

Clinical Gotchas

Microvascular dysfunction (diabetes, HFpEF) → falsely low FFR despite epicardial disease

Tandem lesions: FFR measures combined effect; difficult to attribute ischaemia to single lesion

Left main stenosis: FFR may underestimate true ischaemic burden

Chronic total occlusions: FFR not reliable for viability assessment

Section 4

Next Steps

FFR ≥0.80 (Not Ischaemic)

Defer PCI; medical therapy optimisation

Serial angiography at 6–12 months if high-risk features

Repeat FFR if anatomy changes or symptoms worsen

Culprit lesion PCI still appropriate if acute presentation

FFR 0.75–0.80 (Borderline)

Consider iFR (rest pressure ratio index) for confirmation

Conservative management if stable chronic CAD

Stress testing to correlate with objective ischaemia

Close follow-up; repeat FFR if lesion progression suspected

FFR <0.75 (Ischaemic)

PCI with modern stent (DES) recommended

Dual antiplatelet therapy ≥12 months (standard)

Serial follow-up catheterism if DAPT not tolerated

Consider multivessel FFR-guided revascularisation strategy

Complementary Calculators

iFR Calculator

SYNTAX Score

Duke Treadmill Score

DAPT Score

Cardiac Output Index

Section 5

Evidence Appraisal

Landmark Trials

Section 6

Literature

Development

Developed by Prof. Nico Pijls (Maastricht, Netherlands) and Dr. Bernard De Bruyne (Brugge, Belgium) in the late 1990s. FFR-guided PCI has become standard practice, endorsed by all major cardiology guidelines for functional lesion assessment.

Last Comprehensive Review: 2026

Related Cardiovascular Tools

Cardiac Output Index

CHA2DS2-VASc

CHADS2

Cornell Voltage Criteria

CRUSADE Bleeding Score

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FFR (Fractional Flow Reserve)

FFR (Fractional Flow Reserve): Pressure-wire derived index to assess functional significance of coronary lesions.

Pressure Measurements (at maximal hyperaemia)

Distal Coronary Pressure — Pd (mmHg)

Aortic Pressure — Pa (mmHg)

Formula

FFR = Pd / Pa

Guidelines & Evidence

Clinical Details

Section 1

When to Use

Functional assessment of coronary lesion severity during angiography

Decision-making: proceed with PCI vs. defer in intermediate stenosis

Multivessel disease triage (defer non-culprit lesions if FFR >0.80)

Guidance for staged revascularization strategy

≥50% but <90% angiographic stenosis requiring physiologic assessment

Key Points

FFR 0.75–0.80: borderline lesions benefit from serial assessment or iFR

FFR-guided PCI reduces MACE vs. angiography-only guided strategy

ESC/AHA recommend FFR for intermediate coronary lesions

Requires adenosine hyperaemia or equivalent stress; adenosine-free alternatives (iFR, RFR) emerging

Section 2

Formula & Logic

Formula

Interpretation

FFR Value	Clinical Significance	Recommendation
≥0.80	Not ischaemic	Defer PCI; medical therapy
0.75–0.80	Borderline	Consider serial or iFR
<0.75	Ischaemic	PCI recommended
<0.50	Severe ischaemia	PCI strongly indicated