Dancing with the “star”: The role of subintimal dissection/re‐entry strategies in coronary chronic total occlusion interventions

Abstract

There is currently a fierce debate among coronary chronic total occlusion (CTO) percutaneous coronary intervention (PCI) experts who advocate that dissection/re-entry CTO crossing should be avoided at any cost, and those who believe that dissection/re-entry is acceptable or even preferred, both as a primary approach to CTOs (to maximize efficiency) and when other techniques fail [1]. Given that both sides provide rational arguments, the debate is likely to continue, until outcome data becomes available.In this issue of the Journal Godino et al., a group whose tremendous contributions have pioneered the field of subintimal CTO interventions, present muchneeded mid-term outcome data of the contrast-guided subintimal tracking and re-entry (STAR) technique [2]. In their CTO practice, the contrast-guided STAR technique was used in approximately 20% of cases of successful CTO PCI after conventional attempts failed. Although conclusions are limited since only successful procedures were included in the present analysis, the contrast-guided STAR technique appeared to be safe, with low risk for periprocedural myocardial infarction. This is quite important given that side branches are likely to occlude after subintimal crossing followed by stenting. During 2 years of follow-up, the risk of stent thrombosis was low and similar to conventional CTO crossing techniques. However, the contrast-guided STAR technique was associated with significantly higher angiographic restenosis rates (54% vs. 30%) and need for target vessel revascularization (48% vs. 21%). Moreover, approximately 40% of restenosis in both groups was occlusive.Godino et al. convincingly demonstrate that the risk of restenosis after CTO PCI using the contrast-guided STAR technique is much higher than the conventional antegrade CTO crossing techniques. This is similar to the outcomes of the original STAR technique [3] and suggests that the contrast-guided STAR technique should not be used as a primary, but only as bailout strategy. Moreover, given the high-restenosis rates, routine angiographic follow-up at 3-6 months may be of value in such patients to identify early restenosis and prevent it from becoming occlusive.Several questions remain: First, is it preferable to use subintimal dissection/reentry to successfully recanalize a CTO or to abort the procedure if subintimal entry occurs? Although most CTO operators would choose the former over the latter accepting the higher restenosis rate (especially for patients who are not candidates for surgical revascularization), the question remains open.Second, are dissection/re-entry techniques safe? Although no major complications, such as stent thrombosis or aneurysm formation were not observed with guided STAR in this study, additional studies are needed to confirm that adverse long-term sequelae are indeed rare [4].Third, can the high-restenosis rates observed with contrast-guided STAR be extrapolated to other dissection re-entry techniques? There are many reasons why the answer may be no. Contrast-guided STAR creates...

Contemporary issues of percutaneous coronary intervention in heavily calcified chronic total occlusions: an expert review from the European CTO Club

“…Unfavourable histopathological features of CTOs, such as the presence of severe calcification, increase the complexity of treatment. In particular, heavy calcification (HC) may preclude wire advancement within the intraplaque space of the occlusion, forcing the operator to use extraplaque techniques that are associated with higher periprocedural risk and a potentially poorer outcome 1,2 . In addition, even after a successful wire crossing, advancing balloons and deploying stents can become challenging.…”