Copyright ©The Author(s) 2015.
World J Cardiol. Sep 26, 2015; 7(9): 525-538
Published online Sep 26, 2015. doi: 10.4330/wjc.v7.i9.525
Table 2 Main parameters available to assess coronary macrovascular and microvascular circulation
TechniqueCutoff valueImplicationsCommentary
CFR< 2Unspecific macrovascular and microvascular inability to increase flowPatients with CFR > 2 have favorable outcomes
FFR ≤ 0.8Functionally significant epicardial stenosisExtensive clinical validation
Requires vasodilation
iFR ≤ 0.9Functionally significant epicardial stenosisFunctionally significant epicardial stenosis
HSR0.8 mmHg × s/cmFunctionally significant epicardial stenosisRequires doppler-pressure wire
Convenient in the presence FFR/CFR discordances
HMR> 2 mmHg × s/cmMicrovascular dysfunctionRequires doppler-pressure wire
IMR> 25 mmHg × sMicrovascular dysfunctionThermodilution method