The IMAGINATION trial is an investigator-initiated, prospective, single-center study of symptomatic patients with a native chronic total occlusion (CTO) undergoing intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) with a drug-coated balloon (DCB). Post-PCI IVUS and fractional flow reserve (FFR) at baseline and at 6-months follow-up will be performed. In addition, patients included in the coronary computed tomography angiography (CCTA) substudy will undergo CCTA at 12-months follow-up. The aim of this study is to evaluate the efficacy and safety of DCB-only approach in native coronary CTO.

Whereas CTO PCI techniques and success rates have significantly improved during the last decade, CTOs still pose a significant technical challenge for accurate stent sizing (primarily due to negative remodelling and subsequent distal vessel dilatation post-PCI) resulting in a potentially increased risk of stent failure. Hence, the concept of DCB as a definitive treatment for native CTO is appealing and warrants further investigation. The IMAGINATION trial has been designed as a prospective research to: 1) investigate both the immediate and intermediate-term angiographic, IVUS and physiologic efficacy outcomes as well as safety profile of DCB for native vessel coronary CTO, and 2) to provide a basis for future randomized clinical trial comparing DCB to drug-eluting stents.

All patients with CTO will be screened for potential inclusion in the study. After obtaining written informed consent, patients with successful intraplaque guidewire crossing through CTO lesion (excluding the use of dissection and re-entry techniques) will undergo IVUS-guided PCI with a scoring balloon (balloon-to-artery ratio of 1:1) followed by the use of a paclitaxel-coated balloon. Following satisfactory angiographic result, IVUS and physiological measurements (FFR and non-hyperemic pressure ratios) in the target vessel will be performed. At 6-months follow-up, invasive angiography with IVUS and FFR/non-hyperemic pressure ratios in the target vessel will be repeated. In addition, patients with pre-procedural CCTA will undergo follow-up CCTA after 12 months (CCTA substudy).

Inclusion Criteria:

• clinical indication for CTO PCI as determined by the local heart team (presence of angina or equivalent symptoms and/or documented ischemia or viability)
• native CTO lesion as defined by invasive coronary angiography
• informed consent for participation in the study

Exclusion Criteria:

• <18 years of age
• myocardial infarction
• cardiogenic shock
• severe valvular disease
• estimated life expectancy <1 year
• contraindication to PCI
• positive pregnancy test or breast-feeding
• in-stent CTO
• CTO recanalization using antegrade or retrograde dissection and re-entry techniques