Author/Authors :
Sen، نويسنده , , Sayan and Asrress، نويسنده , , Kaleab N. and Nijjer، نويسنده , , Sukhjinder and Petraco، نويسنده , , Ricardo and Malik، نويسنده , , Iqbal S. and Foale، نويسنده , , Rodney A. and Mikhail، نويسنده , , Ghada W. and Foin، نويسنده , , Nicolas and Broyd، نويسنده , , Christopher and Hadjiloizou، نويسنده , , Nearchos and Sethi، نويسنده , , Amarjit and Al-Bustami، نويسنده , , Mahmud and Hackett، نويسنده , , David A. Khan، نويسنده , , Masood A. and Khawaja، نويسنده , , Muhammed Z. and Baker، نويسنده , , Christopher S. and Bellamy، نويسنده , , Michael and Parker، نويسنده , , Kim H. and Hughes، نويسنده , , Alun D. and Francis، نويسنده , , Darrel P. and Mayet، نويسنده , , Jamil and Di Mario، نويسنده , , Carlo and Escaned، نويسنده , , Javier and Redwood، نويسنده , , Simon and Davies، نويسنده , , Justin E.، نويسنده ,
Abstract :
Objectives
tudy sought to determine if adenosine administration is required for the pressure-only assessment of coronary stenoses.
ound
stantaneous wave-free ratio (iFR) is a vasodilator-free pressure-only measure of the hemodynamic severity of a coronary stenosis comparable to fractional flow reserve (FFR) in diagnostic categorization. In this study, we used hyperemic stenosis resistance (HSR), a combined pressure-and-flow index, as an arbiter to determine when iFR and FFR disagree which index is most representative of the hemodynamic significance of the stenosis. We then test whether administering adenosine significantly improves diagnostic performance of iFR.
s
vessels, intracoronary pressure and flow velocity was measured distal to the stenosis at rest and during adenosine-mediated hyperemia. The iFR (at rest and during adenosine administration [iFRa]), FFR, HSR, baseline, and hyperemic microvascular resistance were calculated using automated algorithms.
s
FR and FFR disagreed (4 cases, or 7.7% of the study population), HSR agreed with iFR in 50% of cases and with FFR in 50% of cases. Differences in magnitude of microvascular resistance did not influence diagnostic categorization; iFR, iFRa, and FFR had equally good diagnostic agreement with HSR (receiver-operating characteristic area under the curve 0.93 iFR vs. 0.94 iFRa and 0.96 FFR, p = 0.48).
sions
d FFR had equivalent agreement with classification of coronary stenosis severity by HSR. Further reduction in resistance by the administration of adenosine did not improve diagnostic categorization, indicating that iFR can be used as an adenosine-free alternative to FFR. (Classification Accuracy of Pressure-Only Ratios Against Indices Using Flow Study [CLARIFY]; NCT01118481)
