Incidence and impact on midterm outcome of intimal versus subintimal tracking with both antegrade and retrograde approaches in patients with successful recanalisation of chronic total occlusions: J-PROCTOR 2 study.

AIMS: The aim of this study was to assess the incidence and impact on midterm outcomes of intimal versus subintimal tracking with both antegrade and retrograde approaches in patients undergoing successful percutaneous coronary intervention for chronic total occlusion (CTO).

METHODS AND RESULTS: In 2012, a total of 1,573 CTO cases from 30 hospitals were enrolled in the Japanese CTO registry. Successful guidewire crossing was performed in 1,411 cases (89.7%). Among them, the guidewire penetration position was clearly identified using intravascular ultrasound (IVUS) imaging in 352 cases, and clinical follow-up at 12 months was performed in 323 cases. These 323 cases were enrolled in this retrospective study: 242 cases were treated with the antegrade approach (antegrade group) and 81 cases were treated with the retrograde approach (retrograde group). The endpoint of this study was target vessel revascularisation (TVR) and major adverse cardiac events (MACE) at 12-month follow-up. Subintimal tracking occurred more frequently in the retrograde group (11.6% vs. 30.9%, p<0.01). TVR was more frequent in the subintimal tracking group in the retrograde group (7.1% vs. 16.0%, p=0.03) but not in the antegrade group (2.8% vs. 3.6%, p=0.99). Although the occlusion length was similar, the subintimal tracking group required a longer stent length compared to the intimal tracking group in the retrograde approach (59.7±24.4 mm vs. 74.0±24.4 mm, p<0.01).

CONCLUSIONS: Subintimal tracking was more frequent in the retrograde approach. Intimal tracking should be recommended in the retrograde approach to reduce stent length and to improve follow-up outcomes.