Operator experience and clinical outcomes of percutaneous coronary intervention for chronic total occlusion: insights from a pooled analysis of the Japanese CTO PCI Expert Registry and the Retrograde Summit General Registry.

There have not been enough studies to examine the association between difference in operator experience and technical success rate in contemporary percutaneous coronary intervention for chronic total occlusion (CTO-PCI). The present study sought to provide insights into the impact of operator experience on clinical outcomes of CTO-PCI through a comparison of two largest Japanese CTO-PCI registries consisting of operators with different CTO-PCI experience. After combining clinical data from the Japanese CTO-PCI Expert Registry (ER) 2014-2016 (N = 4316) including CTO-PCI performed by highly experienced operators and the Retrograde Summit General Registry (RSGR) 2014-2016 (N = 2230) including CTO-PCI performed by less experienced operators, a pooled analysis was performed to compare clinical outcomes of CTO-PCI in 2 registries. The overall technical success rate and the incidence of in-hospital major adverse events were comparable between ER and RSGR (90.1% vs 88.9%, p = 0.133, 1.7% vs 1.5%, p = 0.606, respectively). Technical success rate in ER was significantly higher among the patients treated with primary antegrade approach (91.8% vs 89.5%, p = 0.009), whereas there was no significant difference among the patients treated with the primary retrograde approach (85.7% vs 85.3%, p = 0.857). Multivariate analysis suggested ER operator could not be an independent predictor for technical success. CTO-PCI performed by less experienced but appropriately trained operators could achieve similarly high technical success rate with comparable safety compared with those performed by highly experienced specialists in contemporary Japanese context.