Go Beyond the Angiogram

Comprehensive Physiology Indices

Go Beyond the Angiogram

Why Using Physiological Indices Is Essential

Physiological measurements, including hyperemic (FFR) and non-hyperemic pressure ratios (NHPR), Index of Microcirculatory Resistance (IMR), and Coronary Flow Reserve (CFR) are used to assess for epicardial disease and microvascular dysfunction. Physiologic data from PressureWire™ X Guidewire leads to informed decision-making that is proven to improve patient outcomes and prevent unnecessary, repeat hospitalizations.1

Physiological Indices Defined

Objective Diagnosis of Epicardial Disease and Microvascular Dysfunction

View how PressureWire™ X Guidewire measures Fractional Flow Reserve (FFR), Resting Full-cycle Ratio (RFR), Index of Microcirculatory Resistance (IMR) and Coronary Flow Reserve (CFR).

PressureWire X Guidewire
Assessing the Microcirculation

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 Physiology Indices

Physiology-Guided Decision Making Leads to Better Outcomes

Determining the Need for Revascularization
Determining the Need for Revascularization
Assessment for a Coronary Microvascular Dysfunction Diagnosis
Assessment for a Coronary Microvascular Dysfunction Diagnosis

Society Guidelines for Physiologic Indices

 Diagnosing Epicardial StenosisDiagnosing Coronary Microvascular Dysfunction
GuidelinesACC/SCAI (view here)
ESC Guideline 2019 (view here)
AHA/ACC Guidelines (view here)
Cutoff Value≤ 0.82≤ 0.893≥ 251,*< 2.51,*
FormulaPd/Pa at hyperemiaLowest Pd/Pa ratio of whole-cyclePd x Hyperemic FlowHyperemic Flow/Baseline Flow

*IMR and CFR cutoffs in population of ischemia with no obstructive coronary artery disease (INOCA) patients, CorMicA trial.1

RFR is recognized by the Appropriate Use Criteria with an approved coding recommendation by ACC/SCAI.

Assessing whether Epicardial Stenosis needs intervention because there's more to CAD than an angiogram shows

Assessing Coronary Microvascular Dysfunction (CMD) because CMD may contribute to recurrent angina


  1. Ford TJ, et al. 1-year outcomes of angina management guided by invasive coronary function testing (CorMicA). J Am Coll Card Intu. 2020;13:33-45.
  2. Jeremias A, et al. A test in context: fractional flow reserve: accuracy, prognostic implications, and limitations. J Am Coll Cardiol. 2017;69(22):2748-2758.
  3. Kobayashi Y, et al. Agreement of the resting distal to aortic coronary pressure with the instantaneous wave-free ratio. J Am Coll Cardiol. 2017;70(17):2105-2113.

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