Comparison of Percutaneous Coronary Intervention Optimization With Fractional Flow Reserve Versus Intravascular Ultrasound in the Treatment of Long Coronary Artery Lesions

PCI to long lesion will be optimized according to the IVUS.

PCI to long lesion will be optimized according to the FFR.

Fractional flow reserve protocol will be applied for both FFR-guided and IVUS-guided PCI groups. FFR will be measured according to the standard practice using intravenous adenosine. FFR will be recorded before PCI at the distal third of the coronary artery and after PCI at the same location. In FFR optimization group more than one post PCI FFR measurements could be acquired if the operators performed additional optimization. In IVUS optimization group only one post PCI FFR measurement will be recorded after which the procedure will be considered to be finished, and no further interventions will be undertaken. The same FFR measurements will be performed at 9-12 months follow-up.