Due to COVID-19 pandemic site refused to include patients in the study

The use of intra coronary physiological assessment with fractional flow reserve (FFR) is nowadays the standard approach to define ischemia-inducing stenosis and guide myocardial revascularization strategy in patients with coronary artery disease. Further, FFR has been shown to be a strong and independent predictor of major adverse cardiac events after stent implantation. A lower value of FFR after stent implantation is associated with a worse clinical prognosis, without a clearly defined threshold above which clinical follow up are similar for all FFR values. Among 750 patients in the Fractional Flow Reserve Post-Stent Registry, the event rate was 29.5% in patients with FFR<0.80 compared to 9 4.9% in patients with FFR>0.95 (p<0.001). However, FFR remains poorly adopted in many cathlabs, partly because of procedural time, discomfort or sides effect during hyperemia, non-uniform adenosine response and economical constraints. This leads to the validation of resting indices (instantaneous wave-free ratio (iFR), diastolic pressure ratio (dPR), and resting full-cycle ratio (RFR) among others). Those indices evaluate coronary physiology without the use of maximal hyperemia and have 15 slightly different threshold compared to FFR (≤0.89 vs 0.80, for iFR and RFR, and FFR 16 respectively).In the VALIDATE RFR study, a head-to-head comparison of RFR and iFR from a retrospective analysis, diagnostic accuracy of RFR was 97.4% with an area under the curve 1 (AUC) of 99.6%. In the more recent RE-VALIDATE RFR study, 431 patients with 501 lesions 2 were prospectively evaluated for the diagnostic performance of RFR in all-comers patients. Compared to iFR, RFR achieved high diagnostic accuracy, sensitivity and specificity. These are the reasons why we designed a prospective, non-randomized, clinical trial, to better 18 explore the value of RFR before and after PCI in real live and after optimization by post dilation 19 in all-comers patients with coronary artery disease in the Middle East region..

Inclusion Criteria:

• Patient is ≥ 21 years
• The patient is deemed eligible for PCI of at least one coronary stenosis (RFRpre ≤0.89 or FFR≤0.80)
• The patient is able and is willing to comply with all study procedures and process.

Exclusion Criteria:

• The patient is in cardiogenic shock
• The patient has a bifurcation lesion that requires a planned two stents technique
• The patient refuses to participate.
• The patient suffers acute coronary syndrome and should be treated by PCI in the culprit lesion (non-culprit lesions in non-culprit vessel could be included)
• The patient has an ostial stenosis to be treated by PCI

Male and female subjects could be enrolled in the present study if they are 21 years old or older at the time of inclusion. The trial will enroll 100 patients who need to meet ALL eligibility criteria and provide written informed consent prior to inclusion.