ULTRA-CTO is a prospective multicentre non-randomised investigator-initiated trial designed to enrol 200 subjects with an indication for PCI CTO and who have at least one intermediate (angiographically 30-90%) stenosis in a non-CTO vessel or major side branch of the CTO vessel with a diameter of at least 2mm.~The main objective of the study is to evaluate both the value of post-PCI RFR and post-PCI FFR for detecting suboptimal stent result (SSR) in the acute phase and the stability of these measurements over time.~After angiographically successful CTO PCI, intra-coronary physiologic assessment (RFR, FFR, coronary flow reserve (CFR) and index of microcirculatory resistance (IMR)) of the CTO vessel will be performed directly. A staged procedure including several measurements is planned at 4 ± 2 weeks after the index procedure. These measurements include same intra-coronary physiologic measurements as performed at index procedure and optical coherence tomography (OCT) imaging of the stented segment in the CTO target vessel.~Prior to the staged procedure occurrence of cardiovascular events and clinical classification will be assessed.
ULTRA-CTO is a prospective multicentre non-randomised investigator-initiated trial designed to enrol 200 subjects with an indication for percutaneous coronary intervention (PCI) of chronic total occluded (CTO) coronary artery and who have at least one intermediate (angiographically 30-90%) stenosis in a non-CTO vessel or major side branch of the CTO vessel with a diameter of at least 2 mm.~The main objective of the study is to assess the predictive value of post-PCI resting full-cycle ratio (RFR) and fractional flow reserve (FFR) with regard to Fractional flow reserve (SSR) in CTO patients.