The acute procedural results and subsequent clinical outcomes after CTO-PCI: main-analysis of the japanese CTO-PCI expert registry

Abstract Background The prospective and nonrandomized registry by Japanese Board of chronic total occlusion (CTO) experts has been finished. The large-scale clinical data related with acute procedural results and subsequent clinical outcomes after CTO-percutaneous coronary intervention (PCI) has received limited study. Objectives The aim of this study was to make clear the procedural results comparing the different primary CTO-PCI approaches and the clinical outcomes after successful CTO-PCI. Methods Between January 2014 and December 2022, a total of 11,674 CTO-PCI patients were consecutively enrolled in this registry. We compared the acute procedural results between 2 groups; primary antegrade approach (PAA) versus primary retrograde approach (PRA), following the intention-to-treat principle. The key outcome of interest was a technical success that was defined as successful stent implantation, residual diameter stenosis <30% within the treated segment, and restoration of TIMI grade 3 flow. The clinical outcomes after achieving technical success of CTO-PCI were assessed in terms of major adverse clinical events (MACE) that were composed of all-cause death, myocardial infarction (MI), and target lesion revascularization (TLR). Moreover, the technical failed factors were also investigated with multivariate analyses. Results Of overall, the technical success rate was 91.9%, but there were significant differences between PAA and PRA groups in terms of the success rate (93.2% vs 88.3%; p < 0.001). The success rates of switching strategy to final antegrade approach after retrograde failure were very low among both groups (PAA; 55.8%, PRA; 68.1%). Of retrograde success group, the successful channel tracking tended to using septal and graft route (70.8% vs 56.0%; p < 0.001). Severe calcification and tortuosity of CTO lesion were stronger predictors of failed CTO-PCI than the other factors of J-CTO score. Also, The median follow-up duration was 446.7±613.4 days. At 1 year, the clinical incidence of MACE was 9.4%. The individual components of MACE were also shown lower rates (All-cause death; 2.6%, MI; 0.8%, TLR; 6.3%). Conclusions In this large cohort of Japanese CTO-PCI registry, CTO-PCI by highly experienced specialists achieved a high technical success rate and clinical impacts. Retrograde approach has been a key to technical success of CTO-PCI in this study.