LAUSR

The technical outcome of poor distal vessel quality (PDV) on chronic total occlusion (CTO) percutaneous coronary intervention (PCI) is yet to be clearly elucidated. PDV has not been evaluated in scoring systems. We examined 193 consecutive CTO–PCIs performed in January 2013–December 2017. The endpoint, including the technical outcomes in these patients between with and without PDV, was analyzed. Moreover, we re-evaluated the predictors for CTO–PCI difficulty according to Japan-CTO score. Out of 193 CTO–PCIs, 181 (93.8%) achieved technical success [including 101 (55.8%) with and 80 (44.2%) without PDV]. In patients with and without PDV, the success rates of guidewire crossing using only the antegrade technique were 46.5% vs. 83.8%, respectively ( p  < 0.0001) and using the retrograde approach were 53.5% vs. 16.3%, respectively ( p  < 0.0001). Moreover, there were 56 non-interventional collateral channels in 181 patients. The successful rate of primary antegrade approach was significantly lower and the rate of a rescue retrograde approach was significantly higher with PDV (37.2% vs. 62.8%, 76.9% vs. 23.1%, respectively; p  < 0.0119). Significant predictors associated with successful guidewire crossings of ≤ 30 min included blunt stump, calcification, bending, occlusion length ≥ 20 mm, retry lesion following Japan-CTO score, and PDV ( p  < 0.05, all). Multivariate analyses demonstrated that blunt stump, calcification, bending, retry lesion, and PDV were independent predictors of unsuccessful guidewire crossing of ≤ 30 min (odds ratio [OR] 0.31, 95% confidence interval [CI] 0.13–0.71, p  = 0.0039; OR 0.34, 95% CI 0.16–0.71, p  = 0.0035; OR 0.17, 95% CI 0.05–0.60, p  = 0.0034; OR 0.18, 95% CI 0.06–0.54, p  = 0.0008; and OR 0.19, 95% CI 0.09–0.41, p  < 0.0001, respectively). PDV could affect the technical outcome of CTO–PCI.